WorldWideScience

Sample records for sampling survey methodology

  1. Sample size methodology

    CERN Document Server

    Desu, M M

    2012-01-01

    One of the most important problems in designing an experiment or a survey is sample size determination and this book presents the currently available methodology. It includes both random sampling from standard probability distributions and from finite populations. Also discussed is sample size determination for estimating parameters in a Bayesian setting by considering the posterior distribution of the parameter and specifying the necessary requirements. The determination of the sample size is considered for ranking and selection problems as well as for the design of clinical trials. Appropria

  2. Customer satisfaction surveys: Methodological recommendations for financial service providers

    Directory of Open Access Journals (Sweden)

    Đorđić Marko

    2010-01-01

    Full Text Available This methodological article investigates practical challenges that emerge when conducting customer satisfaction surveys (CSS for financial service providers such as banks, insurance or leasing companies, and so forth. It displays methodological recommendations in reference with: (a survey design, (b sampling, (c survey method, (d questionnaire design, and (e data acquisition. Article provides appropriate explanations that usage of: two-stage survey design, SRS method, large samples, and rigorous fieldwork preparation can enhance the overall quality of CSS in financial services. Proposed methodological recommendations can primarily be applied to the primary quantitative marketing research in retail financial services. However, majority of them can be successfully applied when conducting primary quantitative marketing research in corporate financial services as well. .

  3. Environmental sample banking-research and methodology

    International Nuclear Information System (INIS)

    Becker, D.A.

    1976-01-01

    The National Bureau of Standards (NBS), in cooperation with the Environment Protection Agency and the National Science Foundation, is engaged in a research program establishing methodology for environmental sample banking. This program is aimed toward evaluating the feasibility of a National Environment Specimen Bank (NESB). The capability for retrospective chemical analyses to evaluate changes in our environment would provide useful information. Much of this information could not be obtained using data from previously analyzed samples. However, to assure validity for these stored samples, they must be sampled, processed and stored under rigorously evaluated, controlled and documented conditions. The program currently under way in the NBS Analytical Chemistry Division has 3 main components. The first is an extension survey of available literature concerning problems of contamination, losses and storage. The components of interest include trace elements, pesticides, other trace organics (PCBs, plasticizers, etc.), radionuclides and microbiological species. The second component is an experimental evaluation of contamination and losses during sampling and sample handling. Of particular interest here is research into container cleaning methodology for trace elements, with respect to adsorption, desorption, leaching and partial dissolution by various sample matrices. The third component of this program is an evaluation of existing methodology for long-term sample storage

  4. Web survey methodology

    CERN Document Server

    Callegaro, Mario; Vehovar, Asja

    2015-01-01

    Web Survey Methodology guides the reader through the past fifteen years of research in web survey methodology. It both provides practical guidance on the latest techniques for collecting valid and reliable data and offers a comprehensive overview of research issues. Core topics from preparation to questionnaire design, recruitment testing to analysis and survey software are all covered in a systematic and insightful way. The reader will be exposed to key concepts and key findings in the literature, covering measurement, non-response, adjustments, paradata, and cost issues. The book also discusses the hottest research topics in survey research today, such as internet panels, virtual interviewing, mobile surveys and the integration with passive measurements, e-social sciences, mixed modes and business intelligence. The book is intended for students, practitioners, and researchers in fields such as survey and market research, psychological research, official statistics and customer satisfaction research.

  5. [The methodology and sample description of the National Survey on Addiction Problems in Hungary 2015 (NSAPH 2015)].

    Science.gov (United States)

    Paksi, Borbala; Demetrovics, Zsolt; Magi, Anna; Felvinczi, Katalin

    2017-06-01

    This paper introduces the methods and methodological findings of the National Survey on Addiction Problems in Hungary (NSAPH 2015). Use patterns of smoking, alcohol use and other psychoactive substances were measured as well as that of certain behavioural addictions (problematic gambling - PGSI, DSM-V, eating disorders - SCOFF, problematic internet use - PIUQ, problematic on-line gaming - POGO, problematic social media use - FAS, exercise addictions - EAI-HU, work addiction - BWAS, compulsive buying - CBS). The paper describes the applied measurement techniques, sample selection, recruitment of respondents and the data collection strategy as well. Methodological results of the survey including reliability and validity of the measures are reported. The NSAPH 2015 research was carried out on a nationally representative sample of the Hungarian adult population aged 16-64 yrs (gross sample 2477, net sample 2274 persons) with the age group of 18-34 being overrepresented. Statistical analysis of the weight-distribution suggests that weighting did not create any artificial distortion in the database leaving the representativeness of the sample unaffected. The size of the weighted sample of the 18-64 years old adult population is 1490 persons. The extent of the theoretical margin of error in the weighted sample is ±2,5%, at a reliability level of 95% which is in line with the original data collection plans. Based on the analysis of reliability and the extent of errors beyond sampling within the context of the database we conclude that inconsistencies create relatively minor distortions in cumulative prevalence rates; consequently the database makes possible the reliable estimation of risk factors related to different substance use behaviours. The reliability indexes of measurements used for prevalence estimates of behavioural addictions proved to be appropriate, though the psychometric features in some cases suggest the presence of redundant items. The comparison of

  6. Methodology for performing surveys for fixed contamination

    International Nuclear Information System (INIS)

    Durham, J.S.; Gardner, D.L.

    1994-10-01

    This report describes a methodology for performing instrument surveys for fixed contamination that can be used to support the release of material from radiological areas, including release to controlled areas and release from radiological control. The methodology, which is based on a fast scan survey and a series of statistical, fixed measurements, meets the requirements of the U.S. Department of Energy Radiological Control Manual (RadCon Manual) (DOE 1994) and DOE Order 5400.5 (DOE 1990) for surveys for fixed contamination and requires less time than a conventional scan survey. The confidence interval associated with the new methodology conforms to the draft national standard for surveys. The methodology that is presented applies only to surveys for fixed contamination. Surveys for removable contamination are not discussed, and the new methodology does not affect surveys for removable contamination

  7. Methodological design of the National Health and Nutrition Survey 2016

    OpenAIRE

    Martín Romero-Martínez; Teresa Shamah-Levy; Lucia Cuevas-Nasu; Ignacio Méndez Gómez-Humarán; Elsa Berenice Gaona-Pineda; Luz María Gómez-Acosta; Juan Ángel Rivera-Dommarco; Mauricio Hernández-Ávila

    2017-01-01

    Objective. Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC) 2016. Materials and methods. The Ensanut-MC is a national probabilistic survey whose objective population are the in­habitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organizat...

  8. Methodology of the National School-based Health Survey in Malaysia, 2012.

    Science.gov (United States)

    Yusoff, Fadhli; Saari, Riyanti; Naidu, Balkish M; Ahmad, Noor Ani; Omar, Azahadi; Aris, Tahir

    2014-09-01

    The National School-Based Health Survey 2012 was a nationwide school health survey of students in Standard 4 to Form 5 (10-17 years of age), who were schooling in government schools in Malaysia during the period of data collection. The survey comprised 3 subsurveys: the Global School Health Survey (GSHS), the Mental Health Survey, and the National School-Based Nutrition Survey. The aim of the survey was to provide data on the health status of adolescents in Malaysia toward strengthening the adolescent health program in the country. The design of the survey was created to fulfill the requirements of the 3 subsurveys. A 2-stage stratified sampling method was adopted in the sampling. The methods for data collection were via questionnaire and physical examination. The National School-Based Health Survey 2012 adopted an appropriate methodology for a school-based survey to ensure valid and reliable findings. © 2014 APJPH.

  9. Survey research with a random digit dial national mobile phone sample in Ghana: Methods and sample quality

    Science.gov (United States)

    Sefa, Eunice; Adimazoya, Edward Akolgo; Yartey, Emmanuel; Lenzi, Rachel; Tarpo, Cindy; Heward-Mills, Nii Lante; Lew, Katherine; Ampeh, Yvonne

    2018-01-01

    Introduction Generating a nationally representative sample in low and middle income countries typically requires resource-intensive household level sampling with door-to-door data collection. High mobile phone penetration rates in developing countries provide new opportunities for alternative sampling and data collection methods, but there is limited information about response rates and sample biases in coverage and nonresponse using these methods. We utilized data from an interactive voice response, random-digit dial, national mobile phone survey in Ghana to calculate standardized response rates and assess representativeness of the obtained sample. Materials and methods The survey methodology was piloted in two rounds of data collection. The final survey included 18 demographic, media exposure, and health behavior questions. Call outcomes and response rates were calculated according to the American Association of Public Opinion Research guidelines. Sample characteristics, productivity, and costs per interview were calculated. Representativeness was assessed by comparing data to the Ghana Demographic and Health Survey and the National Population and Housing Census. Results The survey was fielded during a 27-day period in February-March 2017. There were 9,469 completed interviews and 3,547 partial interviews. Response, cooperation, refusal, and contact rates were 31%, 81%, 7%, and 39% respectively. Twenty-three calls were dialed to produce an eligible contact: nonresponse was substantial due to the automated calling system and dialing of many unassigned or non-working numbers. Younger, urban, better educated, and male respondents were overrepresented in the sample. Conclusions The innovative mobile phone data collection methodology yielded a large sample in a relatively short period. Response rates were comparable to other surveys, although substantial coverage bias resulted from fewer women, rural, and older residents completing the mobile phone survey in

  10. Survey research with a random digit dial national mobile phone sample in Ghana: Methods and sample quality.

    Science.gov (United States)

    L'Engle, Kelly; Sefa, Eunice; Adimazoya, Edward Akolgo; Yartey, Emmanuel; Lenzi, Rachel; Tarpo, Cindy; Heward-Mills, Nii Lante; Lew, Katherine; Ampeh, Yvonne

    2018-01-01

    Generating a nationally representative sample in low and middle income countries typically requires resource-intensive household level sampling with door-to-door data collection. High mobile phone penetration rates in developing countries provide new opportunities for alternative sampling and data collection methods, but there is limited information about response rates and sample biases in coverage and nonresponse using these methods. We utilized data from an interactive voice response, random-digit dial, national mobile phone survey in Ghana to calculate standardized response rates and assess representativeness of the obtained sample. The survey methodology was piloted in two rounds of data collection. The final survey included 18 demographic, media exposure, and health behavior questions. Call outcomes and response rates were calculated according to the American Association of Public Opinion Research guidelines. Sample characteristics, productivity, and costs per interview were calculated. Representativeness was assessed by comparing data to the Ghana Demographic and Health Survey and the National Population and Housing Census. The survey was fielded during a 27-day period in February-March 2017. There were 9,469 completed interviews and 3,547 partial interviews. Response, cooperation, refusal, and contact rates were 31%, 81%, 7%, and 39% respectively. Twenty-three calls were dialed to produce an eligible contact: nonresponse was substantial due to the automated calling system and dialing of many unassigned or non-working numbers. Younger, urban, better educated, and male respondents were overrepresented in the sample. The innovative mobile phone data collection methodology yielded a large sample in a relatively short period. Response rates were comparable to other surveys, although substantial coverage bias resulted from fewer women, rural, and older residents completing the mobile phone survey in comparison to household surveys. Random digit dialing of mobile

  11. Survey research with a random digit dial national mobile phone sample in Ghana: Methods and sample quality.

    Directory of Open Access Journals (Sweden)

    Kelly L'Engle

    Full Text Available Generating a nationally representative sample in low and middle income countries typically requires resource-intensive household level sampling with door-to-door data collection. High mobile phone penetration rates in developing countries provide new opportunities for alternative sampling and data collection methods, but there is limited information about response rates and sample biases in coverage and nonresponse using these methods. We utilized data from an interactive voice response, random-digit dial, national mobile phone survey in Ghana to calculate standardized response rates and assess representativeness of the obtained sample.The survey methodology was piloted in two rounds of data collection. The final survey included 18 demographic, media exposure, and health behavior questions. Call outcomes and response rates were calculated according to the American Association of Public Opinion Research guidelines. Sample characteristics, productivity, and costs per interview were calculated. Representativeness was assessed by comparing data to the Ghana Demographic and Health Survey and the National Population and Housing Census.The survey was fielded during a 27-day period in February-March 2017. There were 9,469 completed interviews and 3,547 partial interviews. Response, cooperation, refusal, and contact rates were 31%, 81%, 7%, and 39% respectively. Twenty-three calls were dialed to produce an eligible contact: nonresponse was substantial due to the automated calling system and dialing of many unassigned or non-working numbers. Younger, urban, better educated, and male respondents were overrepresented in the sample.The innovative mobile phone data collection methodology yielded a large sample in a relatively short period. Response rates were comparable to other surveys, although substantial coverage bias resulted from fewer women, rural, and older residents completing the mobile phone survey in comparison to household surveys. Random digit

  12. National Sample Survey of Registered Nurses II. Status of Nurses: November 1980.

    Science.gov (United States)

    Bentley, Barbara S.; And Others

    This report provides data describing the nursing population as determined by the second national sample survey of registered nurses. A brief introduction is followed by a chapter that presents an overview of the survey methodology, including details on the sampling design, the response rate, and the statistical reliability. Chapter 3 provides a…

  13. [Methodological design of the National Health and Nutrition Survey 2016].

    Science.gov (United States)

    Romero-Martínez, Martín; Shamah-Levy, Teresa; Cuevas-Nasu, Lucía; Gómez-Humarán, Ignacio Méndez; Gaona-Pineda, Elsa Berenice; Gómez-Acosta, Luz María; Rivera-Dommarco, Juan Ángel; Hernández-Ávila, Mauricio

    2017-01-01

    Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC) 2016. The Ensanut-MC is a national probabilistic survey whose objective population are the inhabitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organization. A final sample of 9 479 completed household interviews, and a sample of 16 591 individual interviews. The response rate for households was 77.9%, and the response rate for individuals was 91.9%. The Ensanut-MC probabilistic design allows valid statistical inferences about interest parameters for Mexico´s public health and nutrition, specifically on overweight, obesity and diabetes mellitus. Updated information also supports the monitoring, updating and formulation of new policies and priority programs.

  14. Surveying immigrants without sampling frames - evaluating the success of alternative field methods.

    Science.gov (United States)

    Reichel, David; Morales, Laura

    2017-01-01

    This paper evaluates the sampling methods of an international survey, the Immigrant Citizens Survey, which aimed at surveying immigrants from outside the European Union (EU) in 15 cities in seven EU countries. In five countries, no sample frame was available for the target population. Consequently, alternative ways to obtain a representative sample had to be found. In three countries 'location sampling' was employed, while in two countries traditional methods were used with adaptations to reach the target population. The paper assesses the main methodological challenges of carrying out a survey among a group of immigrants for whom no sampling frame exists. The samples of the survey in these five countries are compared to results of official statistics in order to assess the accuracy of the samples obtained through the different sampling methods. It can be shown that alternative sampling methods can provide meaningful results in terms of core demographic characteristics although some estimates differ to some extent from the census results.

  15. Musculoskeletal impairment survey in Rwanda: Design of survey tool, survey methodology, and results of the pilot study (a cross sectional survey

    Directory of Open Access Journals (Sweden)

    Simms Victoria

    2007-03-01

    Full Text Available Abstract Background Musculoskeletal impairment (MSI is an important cause of morbidity and mortality worldwide, especially in developing countries. Prevalence studies for MSI in the developing world have used varying methodologies and are seldom directly comparable. This study aimed to develop a new tool to screen for and diagnose MSI and to pilot test the methodology for a national survey in Rwanda. Methods A 7 question screening tool to identify cases of MSI was developed through literature review and discussions with healthcare professionals. To validate the tool, trained rehabilitation technicians screened 93 previously identified gold standard 'cases' and 86 'non cases'. Sensitivity, specificity and positive predictive value were calculated. A standardised examination protocol was developed to determine the aetiology and diagnosis of MSI for those who fail the screening test. For the national survey in Rwanda, multistage cluster random sampling, with probability proportional to size procedures will be used for selection of a cross-sectional, nationally representative sample of the population. Households to be surveyed will be chosen through compact segment sampling and all individuals within chosen households will be screened. A pilot survey of 680 individuals was conducted using the protocol. Results: The screening tool demonstrated 99% sensitivity and 97% specificity for MSI, and a positive predictive value of 98%. During the pilot study 468 out of 680 eligible subjects (69% were screened. 45 diagnoses were identified in 38 persons who were cases of MSI. The subjects were grouped into categories based on diagnostic subgroups of congenital (1, traumatic (17, infective (2 neurological (6 and other acquired(19. They were also separated into mild (42.1%, moderate (42.1% and severe (15.8% cases, using an operational definition derived from the World Health Organisation's International Classification of Functioning, Disability and Health

  16. Methodological design of the National Health and Nutrition Survey 2016

    Directory of Open Access Journals (Sweden)

    Martín Romero-Martínez

    2017-05-01

    Full Text Available Objective. Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC 2016. Materials and methods. The Ensanut-MC is a national probabilistic survey whose objective population are the in­habitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organization. Results. A final sample of 9 479 completed household interviews, and a sample of 16 591 individual interviews. The response rate for households was 77.9%, and the response rate for individuals was 91.9%. Conclusions. The Ensanut-MC probabilistic design allows valid statistical inferences about interest parameters for Mexico´s public health and nutrition, specifically on over­weight, obesity and diabetes mellitus. Updated information also supports the monitoring, updating and formulation of new policies and priority programs.

  17. Northern Marshall Islands radiological survey: sampling and analysis summary

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Eagle, R.J.; Stuart, M.L.

    1981-07-23

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for /sup 241/Am, 6569 for /sup 137/Cs, 4535 for /sup 239 +240/Pu, 4431 for /sup 90/Sr, 1146 for /sup 238/Pu, 269 for /sup 241/Pu, and 114 each for /sup 239/Pu and /sup 240/Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included.

  18. Northern Marshall Islands radiological survey: sampling and analysis summary

    International Nuclear Information System (INIS)

    Robison, W.L.; Conrado, C.L.; Eagle, R.J.; Stuart, M.L.

    1981-01-01

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for 241 Am, 6569 for 137 Cs, 4535 for 239+240 Pu, 4431 for 90 Sr, 1146 for 238 Pu, 269 for 241 Pu, and 114 each for 239 Pu and 240 Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included

  19. SNE's methodological basis - web-based software in entrepreneurial surveys

    DEFF Research Database (Denmark)

    Madsen, Henning

    This overhead based paper gives an introduction to the research methodology applied in the surveys carried out in the SNE-project.......This overhead based paper gives an introduction to the research methodology applied in the surveys carried out in the SNE-project....

  20. Methodological Issues in Survey Research: A Historical Review

    NARCIS (Netherlands)

    de Heer, W.; de Leeuw, E.D.; van der Zouwen, J.

    1999-01-01

    In this paper, we present a historical overview of social surveys and describe the historical development of scientific survey methodology and survey statistics. The origins of survey research can be traced back to the early 19th century and the first scientiflc survey was conducted in England in

  1. From Study to Work: Methodological Challenges of a Graduate Destination Survey in the Western Cape, South Africa

    Science.gov (United States)

    du Toit, Jacques; Kraak, Andre; Favish, Judy; Fletcher, Lizelle

    2014-01-01

    Current literature proposes several strategies for improving response rates to student evaluation surveys. Graduate destination surveys pose the difficulty of tracing graduates years later when their contact details may have changed. This article discusses the methodology of one such a survey to maximise response rates. Compiling a sample frame…

  2. TESTS AND METHODOLOGIES FOR THE SURVEY OF NARROW SPACES

    Directory of Open Access Journals (Sweden)

    L. Perfetti

    2017-02-01

    Full Text Available The research illustrated in this article aimed at identifying a good standard methodology to survey very narrow spaces during 3D investigation of Cultural Heritage. It is an important topic in today’s era of BIM modelling applied to Cultural Heritage. Spaces like staircases, corridors and passages are very common in the architectural or archaeological fields, and obtaining a 3D-oriented survey of those areas can be a very complex task when completeness of the model and high precision are requested. Photogrammetry appears to be the most promising solution in terms of versatility and manoeuvrability also considering the quality of the required data. Fisheye lenses were studied and tested in depth because of their significant advantage in the field of view if compared with rectilinear lenses. This advantage alone can be crucial to reduce the total amount of photos and, as a consequence, to obtain manageable data, to simplify the survey phase and to significantly reduce the elaboration time. In order to overcome the main issue that arise when using fisheye lenses, which is the lack of rules that can be employed to design the survey, a general mathematical formulation to precisely estimate the GSD (Ground Sampling Distance for every optical projection is presented here. A complete survey of a real complex case study was performed in order to test and stress the proposed methodology, and to handle a fisheye-based survey from beginning to end: the photogrammetric survey of the Minguzzi Staircase. It is a complex service spiral-staircase located in the Duomo di Milano with a total height of 25 meters and characterized by a narrow walkable space about 70 centimetres wide.

  3. Sample survey methods as a quality assurance tool in a general practice immunisation audit.

    Science.gov (United States)

    Cullen, R

    1994-04-27

    In a multidoctor family practice there are often just too many sets of patients records to make it practical to repeat an audit by census of even an age band of the practice on a regular basis. This paper attempts to demonstrate how sample survey methodology can be incorporated into the quality assurance cycle. A simple random sample (with replacement) of 120 from 580 children with permanent records who were aged between 6 weeks and 2 years old from an Auckland general practice was performed, with sample size selected to give a predetermined precision. The survey was then repeated after 4 weeks. Both surveys were able to be completed within the course of a normal working day. An unexpectedly low level of under 2 years olds that were recorded as not overdue for any immunisations was found (22.5%) with only a modest improvement after a standard telephone/letter catch up campaign. Seventy-two percent of the sample held a group one community services card. The advantages of properly conducted sample surveys in producing useful estimates of known precision without disrupting office routines excessively were demonstrated. Through some attention to methodology, the trauma of a practice census can be avoided.

  4. Abundance, distribution and diversity of gelatinous predators along the northern Mid-Atlantic Ridge: A comparison of different sampling methodologies.

    Directory of Open Access Journals (Sweden)

    Aino Hosia

    Full Text Available The diversity and distribution of gelatinous zooplankton were investigated along the northern Mid-Atlantic Ridge (MAR from June to August 2004.Here, we present results from macrozooplankton trawl sampling, as well as comparisons made between five different methodologies that were employed during the MAR-ECO survey. In total, 16 species of hydromedusae, 31 species of siphonophores and four species of scyphozoans were identified to species level from macrozooplankton trawl samples. Additional taxa were identified to higher taxonomic levels and a single ctenophore genus was observed. Samples were collected at 17 stations along the MAR between the Azores and Iceland. A divergence in the species assemblages was observed at the southern limit of the Subpolar Frontal Zone. The catch composition of gelatinous zooplankton is compared between different sampling methodologies including: a macrozooplankton trawl; a Multinet; a ringnet attached to bottom trawl; and optical platforms (Underwater Video Profiler (UVP & Remotely Operated Vehicle (ROV. Different sampling methodologies are shown to exhibit selectivity towards different groups of gelatinous zooplankton. Only ~21% of taxa caught during the survey were caught by both the macrozooplankton trawl and the Multinet when deployed at the same station. The estimates of gelatinous zooplankton abundance calculated using these two gear types also varied widely (1.4 ± 0.9 individuals 1000 m-3 estimated by the macrozooplankton trawl vs. 468.3 ± 315.4 individuals 1000 m-3 estimated by the Multinet (mean ± s.d. when used at the same stations (n = 6. While it appears that traditional net sampling can generate useful data on pelagic cnidarians, comparisons with results from the optical platforms suggest that ctenophore diversity and abundance are consistently underestimated, particularly when net sampling is conducted in combination with formalin fixation. The results emphasise the importance of considering

  5. Abundance, distribution and diversity of gelatinous predators along the northern Mid-Atlantic Ridge: A comparison of different sampling methodologies

    Science.gov (United States)

    Falkenhaug, Tone; Baxter, Emily J.

    2017-01-01

    The diversity and distribution of gelatinous zooplankton were investigated along the northern Mid-Atlantic Ridge (MAR) from June to August 2004.Here, we present results from macrozooplankton trawl sampling, as well as comparisons made between five different methodologies that were employed during the MAR-ECO survey. In total, 16 species of hydromedusae, 31 species of siphonophores and four species of scyphozoans were identified to species level from macrozooplankton trawl samples. Additional taxa were identified to higher taxonomic levels and a single ctenophore genus was observed. Samples were collected at 17 stations along the MAR between the Azores and Iceland. A divergence in the species assemblages was observed at the southern limit of the Subpolar Frontal Zone. The catch composition of gelatinous zooplankton is compared between different sampling methodologies including: a macrozooplankton trawl; a Multinet; a ringnet attached to bottom trawl; and optical platforms (Underwater Video Profiler (UVP) & Remotely Operated Vehicle (ROV)). Different sampling methodologies are shown to exhibit selectivity towards different groups of gelatinous zooplankton. Only ~21% of taxa caught during the survey were caught by both the macrozooplankton trawl and the Multinet when deployed at the same station. The estimates of gelatinous zooplankton abundance calculated using these two gear types also varied widely (1.4 ± 0.9 individuals 1000 m-3 estimated by the macrozooplankton trawl vs. 468.3 ± 315.4 individuals 1000 m-3 estimated by the Multinet (mean ± s.d.) when used at the same stations (n = 6). While it appears that traditional net sampling can generate useful data on pelagic cnidarians, comparisons with results from the optical platforms suggest that ctenophore diversity and abundance are consistently underestimated, particularly when net sampling is conducted in combination with formalin fixation. The results emphasise the importance of considering sampling methodology

  6. Abundance, distribution and diversity of gelatinous predators along the northern Mid-Atlantic Ridge: A comparison of different sampling methodologies.

    Science.gov (United States)

    Hosia, Aino; Falkenhaug, Tone; Baxter, Emily J; Pagès, Francesc

    2017-01-01

    The diversity and distribution of gelatinous zooplankton were investigated along the northern Mid-Atlantic Ridge (MAR) from June to August 2004.Here, we present results from macrozooplankton trawl sampling, as well as comparisons made between five different methodologies that were employed during the MAR-ECO survey. In total, 16 species of hydromedusae, 31 species of siphonophores and four species of scyphozoans were identified to species level from macrozooplankton trawl samples. Additional taxa were identified to higher taxonomic levels and a single ctenophore genus was observed. Samples were collected at 17 stations along the MAR between the Azores and Iceland. A divergence in the species assemblages was observed at the southern limit of the Subpolar Frontal Zone. The catch composition of gelatinous zooplankton is compared between different sampling methodologies including: a macrozooplankton trawl; a Multinet; a ringnet attached to bottom trawl; and optical platforms (Underwater Video Profiler (UVP) & Remotely Operated Vehicle (ROV)). Different sampling methodologies are shown to exhibit selectivity towards different groups of gelatinous zooplankton. Only ~21% of taxa caught during the survey were caught by both the macrozooplankton trawl and the Multinet when deployed at the same station. The estimates of gelatinous zooplankton abundance calculated using these two gear types also varied widely (1.4 ± 0.9 individuals 1000 m-3 estimated by the macrozooplankton trawl vs. 468.3 ± 315.4 individuals 1000 m-3 estimated by the Multinet (mean ± s.d.) when used at the same stations (n = 6). While it appears that traditional net sampling can generate useful data on pelagic cnidarians, comparisons with results from the optical platforms suggest that ctenophore diversity and abundance are consistently underestimated, particularly when net sampling is conducted in combination with formalin fixation. The results emphasise the importance of considering sampling methodology

  7. Systematic investigation of gastrointestinal diseases in China (SILC): validation of survey methodology.

    Science.gov (United States)

    Yan, Xiaoyan; Wang, Rui; Zhao, Yanfang; Ma, Xiuqiang; Fang, Jiqian; Yan, Hong; Kang, Xiaoping; Yin, Ping; Hao, Yuantao; Li, Qiang; Dent, John; Sung, Joseph; Zou, Duowu; Johansson, Saga; Halling, Katarina; Liu, Wenbin; He, Jia

    2009-11-19

    Symptom-based surveys suggest that the prevalence of gastrointestinal diseases is lower in China than in Western countries. The aim of this study was to validate a methodology for the epidemiological investigation of gastrointestinal symptoms and endoscopic findings in China. A randomized, stratified, multi-stage sampling methodology was used to select 18,000 adults aged 18-80 years from Shanghai, Beijing, Xi'an, Wuhan and Guangzhou. Participants from Shanghai were invited to provide blood samples and undergo upper gastrointestinal endoscopy. All participants completed Chinese versions of the Reflux Disease Questionnaire (RDQ) and the modified Rome II questionnaire; 20% were also invited to complete the 36-item Short Form Health Survey (SF-36) and Epworth Sleepiness Scale (ESS). The psychometric properties of the questionnaires were evaluated statistically. The study was completed by 16,091 individuals (response rate: 89.4%), with 3219 (89.4% of those invited) completing the SF-36 and ESS. All 3153 participants in Shanghai provided blood samples and 1030 (32.7%) underwent endoscopy. Cronbach's alpha coefficients were 0.89, 0.89, 0.80 and 0.91, respectively, for the RDQ, modified Rome II questionnaire, ESS and SF-36, supporting internal consistency. Factor analysis supported construct validity of all questionnaire dimensions except SF-36 psychosocial dimensions. This population-based study has great potential to characterize the relationship between gastrointestinal symptoms and endoscopic findings in China.

  8. Fisheye Photogrammetry: Tests and Methodologies for the Survey of Narrow Spaces

    Science.gov (United States)

    Perfetti, L.; Polari, C.; Fassi, F.

    2017-02-01

    The research illustrated in this article aimed at identifying a good standard methodology to survey very narrow spaces during 3D investigation of Cultural Heritage. It is an important topic in today's era of BIM modelling applied to Cultural Heritage. Spaces like staircases, corridors and passages are very common in the architectural or archaeological fields, and obtaining a 3D-oriented survey of those areas can be a very complex task when completeness of the model and high precision are requested. Photogrammetry appears to be the most promising solution in terms of versatility and manoeuvrability also considering the quality of the required data. Fisheye lenses were studied and tested in depth because of their significant advantage in the field of view if compared with rectilinear lenses. This advantage alone can be crucial to reduce the total amount of photos and, as a consequence, to obtain manageable data, to simplify the survey phase and to significantly reduce the elaboration time. In order to overcome the main issue that arise when using fisheye lenses, which is the lack of rules that can be employed to design the survey, a general mathematical formulation to precisely estimate the GSD (Ground Sampling Distance) for every optical projection is presented here. A complete survey of a real complex case study was performed in order to test and stress the proposed methodology, and to handle a fisheye-based survey from beginning to end: the photogrammetric survey of the Minguzzi Staircase. It is a complex service spiral-staircase located in the Duomo di Milano with a total height of 25 meters and characterized by a narrow walkable space about 70 centimetres wide.

  9. A Systematic Review of Published Respondent-Driven Sampling Surveys Collecting Behavioral and Biologic Data.

    Science.gov (United States)

    Johnston, Lisa G; Hakim, Avi J; Dittrich, Samantha; Burnett, Janet; Kim, Evelyn; White, Richard G

    2016-08-01

    Reporting key details of respondent-driven sampling (RDS) survey implementation and analysis is essential for assessing the quality of RDS surveys. RDS is both a recruitment and analytic method and, as such, it is important to adequately describe both aspects in publications. We extracted data from peer-reviewed literature published through September, 2013 that reported collected biological specimens using RDS. We identified 151 eligible peer-reviewed articles describing 222 surveys conducted in seven regions throughout the world. Most published surveys reported basic implementation information such as survey city, country, year, population sampled, interview method, and final sample size. However, many surveys did not report essential methodological and analytical information for assessing RDS survey quality, including number of recruitment sites, seeds at start and end, maximum number of waves, and whether data were adjusted for network size. Understanding the quality of data collection and analysis in RDS is useful for effectively planning public health service delivery and funding priorities.

  10. Optimal sampling designs for large-scale fishery sample surveys in Greece

    Directory of Open Access Journals (Sweden)

    G. BAZIGOS

    2007-12-01

    The paper deals with the optimization of the following three large scale sample surveys: biological sample survey of commercial landings (BSCL, experimental fishing sample survey (EFSS, and commercial landings and effort sample survey (CLES.

  11. Methodology of Global Adult Tobacco Survey (GATS), Malaysia, 2011.

    Science.gov (United States)

    Omar, Azahadi; Yusoff, Muhammad Fadhli Mohd; Hiong, Tee Guat; Aris, Tahir; Morton, Jeremy; Pujari, Sameer

    Malaysia participated in the second phase of the Global Adult Tobacco Survey (GATS) in 2011. GATS, a new component of the Global Tobacco Surveillance System, is a nationally representative household survey of adults 15 years old or above. The objectives of GATS Malaysia were to (i) systematically monitor tobacco use among adults and track key indicators of tobacco control and (ii) track the implementation of some of the Framework Convention of Tobacco Control (FCTC)-recommended demand related policies. GATS Malaysia 2011 was a nationwide cross-sectional survey using multistage stratified sampling to select 5112 nationally representative households. One individual aged 15 years or older was randomly chosen from each selected household and interviewed using handheld device. GATS Core Questionnaire with optional questions was pre-tested and uploaded into handheld devices after repeated quality control processes. Data collectors were trained through a centralized training. Manuals and picture book were prepared to aid in the training of data collectors and during data collection. Field-level data were aggregated on a daily basis and analysed twice a week. Quality controls were instituted to ensure collection of high quality data. Sample weighting and analysis were conducted with the assistance of researchers from the Centers for Disease Control and Prevention, Atlanta, USA. GATS Malaysia received a total response rate of 85.3% from 5112 adults surveyed. Majority of the respondents were 25-44 years old and Malays. The robust methodology used in the GATS Malaysia provides national estimates for tobacco used classified by socio-demographic characteristics and reliable data on various dimensions of tobacco control.

  12. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys.

    Directory of Open Access Journals (Sweden)

    Lauren Hund

    Full Text Available Lot quality assurance sampling (LQAS surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we compare these latter cluster LQAS methodologies and provide recommendations for choosing a cluster LQAS design. We compare technical differences in the three methods and determine situations in which the choice of method results in a substantively different design. We consider two different aspects of the methods: the distributional assumptions and the clustering parameterization. Further, we provide software tools for implementing each method and clarify misconceptions about these designs in the literature. We illustrate the differences in these methods using vaccination and nutrition cluster LQAS surveys as example designs. The cluster methods are not sensitive to the distributional assumptions but can result in substantially different designs (sample sizes depending on the clustering parameterization. However, none of the clustering parameterizations used in the existing methods appears to be consistent with the observed data, and, consequently, choice between the cluster LQAS methods is not straightforward. Further research should attempt to characterize clustering patterns in specific applications and provide suggestions for best-practice cluster LQAS designs on a setting-specific basis.

  13. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys.

    Science.gov (United States)

    Hund, Lauren; Bedrick, Edward J; Pagano, Marcello

    2015-01-01

    Lot quality assurance sampling (LQAS) surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we compare these latter cluster LQAS methodologies and provide recommendations for choosing a cluster LQAS design. We compare technical differences in the three methods and determine situations in which the choice of method results in a substantively different design. We consider two different aspects of the methods: the distributional assumptions and the clustering parameterization. Further, we provide software tools for implementing each method and clarify misconceptions about these designs in the literature. We illustrate the differences in these methods using vaccination and nutrition cluster LQAS surveys as example designs. The cluster methods are not sensitive to the distributional assumptions but can result in substantially different designs (sample sizes) depending on the clustering parameterization. However, none of the clustering parameterizations used in the existing methods appears to be consistent with the observed data, and, consequently, choice between the cluster LQAS methods is not straightforward. Further research should attempt to characterize clustering patterns in specific applications and provide suggestions for best-practice cluster LQAS designs on a setting-specific basis.

  14. A review of methodology and analysis of nutrition and mortality surveys conducted in humanitarian emergencies from October 1993 to April 2004

    Directory of Open Access Journals (Sweden)

    Spiegel Paul B

    2007-06-01

    Full Text Available Abstract Background Malnutrition prevalence and mortality rates are increasingly used as essential indicators to assess the severity of a crisis, to follow trends, and to guide decision-making, including allocation of funds. Although consensus has slowly developed on the methodology to accurately measure these indicators, errors in the application of the survey methodology and analysis have persisted. The aim of this study was to identify common methodological weaknesses in nutrition and mortality surveys and to provide practical recommendations for improvement. Methods Nutrition (N = 368 and crude mortality rate (CMR; N = 158 surveys conducted by 33 non-governmental organisations and United Nations agencies in 17 countries from October 1993 to April 2004 were analysed for sampling validity, precision, quality of measurement and calculation according to several criteria. Results One hundred and thirty (35.3% nutrition surveys and 5 (3.2% CMR surveys met the criteria for quality. Quality of surveys varied significantly depending on the agency. The proportion of nutrition surveys that met criteria for quality rose significantly from 1993 to 2004; there was no improvement for mortality surveys during this period. Conclusion Significant errors and imprecision in the methodology and reporting of nutrition and mortality surveys were identified. While there was an improvement in the quality of nutrition surveys over the years, the quality of mortality surveys remained poor. Recent initiatives aimed at standardising nutrition and mortality survey quality should be strengthened. There are still a number of methodological issues in nutrition and mortality surveys in humanitarian emergencies that need further study.

  15. Contributions to sampling statistics

    CERN Document Server

    Conti, Pier; Ranalli, Maria

    2014-01-01

    This book contains a selection of the papers presented at the ITACOSM 2013 Conference, held in Milan in June 2013. ITACOSM is the bi-annual meeting of the Survey Sampling Group S2G of the Italian Statistical Society, intended as an international  forum of scientific discussion on the developments of theory and application of survey sampling methodologies and applications in human and natural sciences. The book gathers research papers carefully selected from both invited and contributed sessions of the conference. The whole book appears to be a relevant contribution to various key aspects of sampling methodology and techniques; it deals with some hot topics in sampling theory, such as calibration, quantile-regression and multiple frame surveys, and with innovative methodologies in important topics of both sampling theory and applications. Contributions cut across current sampling methodologies such as interval estimation for complex samples, randomized responses, bootstrap, weighting, modeling, imputati...

  16. The Hubble Space Telescope Medium Deep Survey Cluster Sample: Methodology and Data

    Science.gov (United States)

    Ostrander, E. J.; Nichol, R. C.; Ratnatunga, K. U.; Griffiths, R. E.

    1998-12-01

    We present a new, objectively selected, sample of galaxy overdensities detected in the Hubble Space Telescope Medium Deep Survey (MDS). These clusters/groups were found using an automated procedure that involved searching for statistically significant galaxy overdensities. The contrast of the clusters against the field galaxy population is increased when morphological data are used to search around bulge-dominated galaxies. In total, we present 92 overdensities above a probability threshold of 99.5%. We show, via extensive Monte Carlo simulations, that at least 60% of these overdensities are likely to be real clusters and groups and not random line-of-sight superpositions of galaxies. For each overdensity in the MDS cluster sample, we provide a richness and the average of the bulge-to-total ratio of galaxies within each system. This MDS cluster sample potentially contains some of the most distant clusters/groups ever detected, with about 25% of the overdensities having estimated redshifts z > ~0.9. We have made this sample publicly available to facilitate spectroscopic confirmation of these clusters and help more detailed studies of cluster and galaxy evolution. We also report the serendipitous discovery of a new cluster close on the sky to the rich optical cluster Cl l0016+16 at z = 0.546. This new overdensity, HST 001831+16208, may be coincident with both an X-ray source and a radio source. HST 001831+16208 is the third cluster/group discovered near to Cl 0016+16 and appears to strengthen the claims of Connolly et al. of superclustering at high redshift.

  17. A Bayesian Justification for Random Sampling in Sample Survey

    Directory of Open Access Journals (Sweden)

    Glen Meeden

    2012-07-01

    Full Text Available In the usual Bayesian approach to survey sampling the sampling design, plays a minimal role, at best. Although a close relationship between exchangeable prior distributions and simple random sampling has been noted; how to formally integrate simple random sampling into the Bayesian paradigm is not clear. Recently it has been argued that the sampling design can be thought of as part of a Bayesian's prior distribution. We will show here that under this scenario simple random sample can be given a Bayesian justification in survey sampling.

  18. Lot quality assurance sampling techniques in health surveys in developing countries: advantages and current constraints.

    Science.gov (United States)

    Lanata, C F; Black, R E

    1991-01-01

    Traditional survey methods, which are generally costly and time-consuming, usually provide information at the regional or national level only. The utilization of lot quality assurance sampling (LQAS) methodology, developed in industry for quality control, makes it possible to use small sample sizes when conducting surveys in small geographical or population-based areas (lots). This article describes the practical use of LQAS for conducting health surveys to monitor health programmes in developing countries. Following a brief description of the method, the article explains how to build a sample frame and conduct the sampling to apply LQAS under field conditions. A detailed description of the procedure for selecting a sampling unit to monitor the health programme and a sample size is given. The sampling schemes utilizing LQAS applicable to health surveys, such as simple- and double-sampling schemes, are discussed. The interpretation of the survey results and the planning of subsequent rounds of LQAS surveys are also discussed. When describing the applicability of LQAS in health surveys in developing countries, the article considers current limitations for its use by health planners in charge of health programmes, and suggests ways to overcome these limitations through future research. It is hoped that with increasing attention being given to industrial sampling plans in general, and LQAS in particular, their utilization to monitor health programmes will provide health planners in developing countries with powerful techniques to help them achieve their health programme targets.

  19. Galaxy redshift surveys with sparse sampling

    International Nuclear Information System (INIS)

    Chiang, Chi-Ting; Wullstein, Philipp; Komatsu, Eiichiro; Jee, Inh; Jeong, Donghui; Blanc, Guillermo A.; Ciardullo, Robin; Gronwall, Caryl; Hagen, Alex; Schneider, Donald P.; Drory, Niv; Fabricius, Maximilian; Landriau, Martin; Finkelstein, Steven; Jogee, Shardha; Cooper, Erin Mentuch; Tuttle, Sarah; Gebhardt, Karl; Hill, Gary J.

    2013-01-01

    Survey observations of the three-dimensional locations of galaxies are a powerful approach to measure the distribution of matter in the universe, which can be used to learn about the nature of dark energy, physics of inflation, neutrino masses, etc. A competitive survey, however, requires a large volume (e.g., V survey ∼ 10Gpc 3 ) to be covered, and thus tends to be expensive. A ''sparse sampling'' method offers a more affordable solution to this problem: within a survey footprint covering a given survey volume, V survey , we observe only a fraction of the volume. The distribution of observed regions should be chosen such that their separation is smaller than the length scale corresponding to the wavenumber of interest. Then one can recover the power spectrum of galaxies with precision expected for a survey covering a volume of V survey (rather than the volume of the sum of observed regions) with the number density of galaxies given by the total number of observed galaxies divided by V survey (rather than the number density of galaxies within an observed region). We find that regularly-spaced sampling yields an unbiased power spectrum with no window function effect, and deviations from regularly-spaced sampling, which are unavoidable in realistic surveys, introduce calculable window function effects and increase the uncertainties of the recovered power spectrum. On the other hand, we show that the two-point correlation function (pair counting) is not affected by sparse sampling. While we discuss the sparse sampling method within the context of the forthcoming Hobby-Eberly Telescope Dark Energy Experiment, the method is general and can be applied to other galaxy surveys

  20. Challenges in dental statistics: survey methodology topics

    OpenAIRE

    Pizzo, Giuseppe; Milani, Silvano; Spada, Elena; Ottolenghi, Livia

    2013-01-01

    This paper gathers some contributions concerning survey methodology in dental research, as discussed during the first Workshop of the SISMEC STATDENT working group on statistical methods and applications in dentistry, held in Ancona on the 28th September 2011.The first contribution deals with the European Global Oral Health Indicators Development (EGOHID) Project which proposed a comprehensive and standardized system of epidemiological tools (questionnaires and clinical forms) for national da...

  1. Novel methodology to isolate microplastics from vegetal-rich samples.

    Science.gov (United States)

    Herrera, Alicia; Garrido-Amador, Paloma; Martínez, Ico; Samper, María Dolores; López-Martínez, Juan; Gómez, May; Packard, Theodore T

    2018-04-01

    Microplastics are small plastic particles, globally distributed throughout the oceans. To properly study them, all the methodologies for their sampling, extraction, and measurement should be standardized. For heterogeneous samples containing sediments, animal tissues and zooplankton, several procedures have been described. However, definitive methodologies for samples, rich in algae and plant material, have not yet been developed. The aim of this study was to find the best extraction protocol for vegetal-rich samples by comparing the efficacies of five previously described digestion methods, and a novel density separation method. A protocol using 96% ethanol for density separation was better than the five digestion methods tested, even better than using H 2 O 2 digestion. As it was the most efficient, simple, safe and inexpensive method for isolating microplastics from vegetal rich samples, we recommend it as a standard separation method. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. National and Regional Surveys of Radon Concentration in Dwellings. Review of Methodology and Measurement Techniques

    International Nuclear Information System (INIS)

    2013-01-01

    Reliable, comparable and 'fit for purpose' results are essential requirements for any decision based on analytical measurements. For the analyst, the availability of tested and validated sampling and analytical procedures is an extremely important tool for carrying out such measurements. For maximum utility, such procedures should be comprehensive, clearly formulated and readily available to both the analyst and the customer for reference. In the specific case of radon surveys, it is very important to design a survey in such a way as to obtain results that can reasonably be considered representative of a population. Since 2004, the Environment Programme of the IAEA has included activities aimed at the development of a set of procedures for the measurement of radionuclides in terrestrial environmental samples. The development of radon measurement procedures for national and regional surveys started with the collection and review of more than 160 relevant scientific papers. On the basis of this review, this publication summarizes the methodology and the measurement techniques suitable for a population representative national or regional survey on radon concentration in the indoor air of dwellings. The main elements of the survey design are described and discussed, such as the sampling scheme, the protocols, the questionnaire and the data analysis, with particular attention to the potential biases that can affect the representativeness of the results. Moreover, the main measurement techniques suitable for national surveys on indoor radon are reviewed, with particular attention to the elements that can affect the precision and accuracy of the results

  3. National and Regional Surveys of Radon Concentration in Dwellings. Review of Methodology and Measurement Techniques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-12-15

    Reliable, comparable and 'fit for purpose' results are essential requirements for any decision based on analytical measurements. For the analyst, the availability of tested and validated sampling and analytical procedures is an extremely important tool for carrying out such measurements. For maximum utility, such procedures should be comprehensive, clearly formulated and readily available to both the analyst and the customer for reference. In the specific case of radon surveys, it is very important to design a survey in such a way as to obtain results that can reasonably be considered representative of a population. Since 2004, the Environment Programme of the IAEA has included activities aimed at the development of a set of procedures for the measurement of radionuclides in terrestrial environmental samples. The development of radon measurement procedures for national and regional surveys started with the collection and review of more than 160 relevant scientific papers. On the basis of this review, this publication summarizes the methodology and the measurement techniques suitable for a population representative national or regional survey on radon concentration in the indoor air of dwellings. The main elements of the survey design are described and discussed, such as the sampling scheme, the protocols, the questionnaire and the data analysis, with particular attention to the potential biases that can affect the representativeness of the results. Moreover, the main measurement techniques suitable for national surveys on indoor radon are reviewed, with particular attention to the elements that can affect the precision and accuracy of the results.

  4. National Sample Survey of Registered Nurses

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Sample Survey of Registered Nurses (NSSRN) Download makes data from the survey readily available to users in a one-stop download. The Survey has been...

  5. Mahalanobis' Contributions to Sample Surveys

    Indian Academy of Sciences (India)

    Sample Survey started its operations in October 1950 under the ... and adopted random cuts for estimating the acreage under jute ... demographic factors relating to indebtedness, unemployment, ... traffic surveys, demand for currency coins and average life of .... Mahalanobis derived the optimum allocation in stratified.

  6. Comparison Of Irms Delhi Methodology With Who Methodology On Immunization Coverage

    Directory of Open Access Journals (Sweden)

    Singh Padam

    1996-01-01

    Full Text Available Research question: What are the merits of IRMS Model over WHO Model for Coverage Evaluation Survey? Which method is superior and appropriate for coverage evolution survey of immunization in our setting? Objective: To compare IRMS Delhi methodology with WHO methodology on Immunization Coverage. Study Design: Cross-Sectional Setting: Urban and Rural both. Participants: Mothers& Children Sample Size: 300 children between 1-2 years and 300 mothers in rural areas and 75 children and 75 mothers in urban areas. Study Variables: Rural, Urban, Cast-Group, Size of the stratum, Literacy, Sex and Cost effectiveness. Outcome Variables: Coverage level of immunization. Analysis: Routine Statistical Analysis. Results: IRMS developed methodology scores better rating over WHO methodology, especially when coverage evolution is attempted in medium size villages with existence of socio-economic seggregation-which remains the main characteristic of the Indian villages.

  7. Using Linked Survey Paradata to Improve Sampling Strategies in the Medical Expenditure Panel Survey

    Directory of Open Access Journals (Sweden)

    Mirel Lisa B.

    2017-06-01

    Full Text Available Using paradata from a prior survey that is linked to a new survey can help a survey organization develop more effective sampling strategies. One example of this type of linkage or subsampling is between the National Health Interview Survey (NHIS and the Medical Expenditure Panel Survey (MEPS. MEPS is a nationally representative sample of the U.S. civilian, noninstitutionalized population based on a complex multi-stage sample design. Each year a new sample is drawn as a subsample of households from the prior year’s NHIS. The main objective of this article is to examine how paradata from a prior survey can be used in developing a sampling scheme in a subsequent survey. A framework for optimal allocation of the sample in substrata formed for this purpose is presented and evaluated for the relative effectiveness of alternative substratification schemes. The framework is applied, using real MEPS data, to illustrate how utilizing paradata from the linked survey offers the possibility of making improvements to the sampling scheme for the subsequent survey. The improvements aim to reduce the data collection costs while maintaining or increasing effective responding sample sizes and response rates for a harder to reach population.

  8. Satellite-aided survey sampling and implementation in low- and middle-income contexts: a low-cost/low-tech alternative.

    Science.gov (United States)

    Haenssgen, Marco J

    2015-01-01

    The increasing availability of online maps, satellite imagery, and digital technology can ease common constraints of survey sampling in low- and middle-income countries. However, existing approaches require specialised software and user skills, professional GPS equipment, and/or commercial data sources; they tend to neglect spatial sampling considerations when using satellite maps; and they continue to face implementation challenges analogous to conventional survey implementation methods. This paper presents an alternative way of utilising satellite maps and digital aides that aims to address these challenges. The case studies of two rural household surveys in Rajasthan (India) and Gansu (China) compare conventional survey sampling and implementation techniques with the use of online map services such as Google, Bing, and HERE maps. Modern yet basic digital technology can be integrated into the processes of preparing, implementing, and monitoring a rural household survey. Satellite-aided systematic random sampling enhanced the spatial representativeness of the village samples and entailed savings of approximately £4000 compared to conventional household listing, while reducing the duration of the main survey by at least 25 %. This low-cost/low-tech satellite-aided survey sampling approach can be useful for student researchers and resource-constrained research projects operating in low- and middle-income contexts with high survey implementation costs. While achieving transparent and efficient survey implementation at low costs, researchers aiming to adopt a similar process should be aware of the locational, technical, and logistical requirements as well as the methodological challenges of this strategy.

  9. The rise of survey sampling

    NARCIS (Netherlands)

    Bethlehem, J.

    2009-01-01

    This paper is about the history of survey sampling. It describes how sampling became an accepted scientific method. From the first ideas in 1895 it took some 50 years before the principles of probability sampling were widely accepted. This papers has a focus on developments in official statistics in

  10. Survey research.

    Science.gov (United States)

    Alderman, Amy K; Salem, Barbara

    2010-10-01

    Survey research is a unique methodology that can provide insight into individuals' perspectives and experiences and can be collected on a large population-based sample. Specifically, in plastic surgery, survey research can provide patients and providers with accurate and reproducible information to assist with medical decision-making. When using survey methods in research, researchers should develop a conceptual model that explains the relationships of the independent and dependent variables. The items of the survey are of primary importance. Collected data are only useful if they accurately measure the concepts of interest. In addition, administration of the survey must follow basic principles to ensure an adequate response rate and representation of the intended target sample. In this article, the authors review some general concepts important for successful survey research and discuss the many advantages this methodology has for obtaining limitless amounts of valuable information.

  11. Alcohol- and Drug-Involved Driving in the United States: Methodology for the 2007 National Roadside Survey

    Science.gov (United States)

    Lacey, John H.; Kelley-Baker, Tara; Voas, Robert B.; Romano, Eduardo; Furr-Holden, C. Debra; Torres, Pedro; Berning, Amy

    2013-01-01

    This article describes the methodology used in the 2007 U.S. National Roadside Survey to estimate the prevalence of alcohol- and drug-impaired driving and alcohol- and drug-involved driving. This study involved randomly stopping drivers at 300 locations across the 48 continental U.S. states at sites selected through a stratified random sampling procedure. Data were collected during a 2-hour Friday daytime session at 60 locations and during 2-hour nighttime weekend periods at 240 locations. Both self-report and biological measures were taken. Biological measures included breath alcohol measurements from 9,413 respondents, oral fluid samples from 7,719 respondents, and blood samples from 3,276 respondents. PMID:21997324

  12. Culturally appropriate methodology in obtaining a representative sample of South Australian Aboriginal adults for a cross-sectional population health study: challenges and resolutions.

    Science.gov (United States)

    Marin, Tania; Taylor, Anne Winifred; Grande, Eleonora Dal; Avery, Jodie; Tucker, Graeme; Morey, Kim

    2015-05-19

    The considerably lower average life expectancy of Aboriginal and Torres Strait Islander Australians, compared with non-Aboriginal and non-Torres Strait Islander Australians, has been widely reported. Prevalence data for chronic disease and health risk factors are needed to provide evidence based estimates for Australian Aboriginal and Torres Strait Islanders population health planning. Representative surveys for these populations are difficult due to complex methodology. The focus of this paper is to describe in detail the methodological challenges and resolutions of a representative South Australian Aboriginal population-based health survey. Using a stratified multi-stage sampling methodology based on the Australian Bureau of Statistics 2006 Census with culturally appropriate and epidemiological rigorous methods, 11,428 randomly selected dwellings were approached from a total of 209 census collection districts. All persons eligible for the survey identified as Aboriginal and/or Torres Strait Islander and were selected from dwellings identified as having one or more Aboriginal person(s) living there at the time of the survey. Overall, the 399 interviews from an eligible sample of 691 SA Aboriginal adults yielded a response rate of 57.7%. These face-to-face interviews were conducted by ten interviewers retained from a total of 27 trained Aboriginal interviewers. Challenges were found in three main areas: identification and recruitment of participants; interviewer recruitment and retainment; and using appropriate engagement with communities. These challenges were resolved, or at least mainly overcome, by following local protocols with communities and their representatives, and reaching agreement on the process of research for Aboriginal people. Obtaining a representative sample of Aboriginal participants in a culturally appropriate way was methodologically challenging and required high levels of commitment and resources. Adhering to these principles has resulted in a

  13. Measuring the health of the Indian elderly: evidence from National Sample Survey data

    Directory of Open Access Journals (Sweden)

    Mahal Ajay

    2010-11-01

    Full Text Available Abstract Background Comparable health measures across different sets of populations are essential for describing the distribution of health outcomes and assessing the impact of interventions on these outcomes. Self-reported health (SRH is a commonly used indicator of health in household surveys and has been shown to be predictive of future mortality. However, the susceptibility of SRH to influence by individuals' expectations complicates its interpretation and undermines its usefulness. Methods This paper applies the empirical methodology of Lindeboom and van Doorslaer (2004 to investigate elderly health in India using data from the 52nd round of the National Sample Survey conducted in 1995-96 that includes both an SRH variable as well as a range of objective indicators of disability and ill health. The empirical testing was conducted on stratified homogeneous groups, based on four factors: gender, education, rural-urban residence, and region. Results We find that region generally has a significant impact on how women perceive their health. Reporting heterogeneity can arise not only from cut-point shifts, but also from differences in health effects by objective health measures. In contrast, we find little evidence of reporting heterogeneity due to differences in gender or educational status within regions. Rural-urban residence does matter in some cases. The findings are robust with different specifications of objective health indicators. Conclusions Our exercise supports the thesis that the region of residence is associated with different cut-points and reporting behavior on health surveys. We believe this is the first paper that applies the Lindeboom-van Doorslaer methodology to data on the elderly in a developing country, showing the feasibility of applying this methodology to data from many existing cross-sectional health surveys.

  14. Large sample NAA facility and methodology development

    International Nuclear Information System (INIS)

    Roth, C.; Gugiu, D.; Barbos, D.; Datcu, A.; Aioanei, L.; Dobrea, D.; Taroiu, I. E.; Bucsa, A.; Ghinescu, A.

    2013-01-01

    A Large Sample Neutron Activation Analysis (LSNAA) facility has been developed at the TRIGA- Annular Core Pulsed Reactor (ACPR) operated by the Institute for Nuclear Research in Pitesti, Romania. The central irradiation cavity of the ACPR core can accommodate a large irradiation device. The ACPR neutron flux characteristics are well known and spectrum adjustment techniques have been successfully applied to enhance the thermal component of the neutron flux in the central irradiation cavity. An analysis methodology was developed by using the MCNP code in order to estimate counting efficiency and correction factors for the major perturbing phenomena. Test experiments, comparison with classical instrumental neutron activation analysis (INAA) methods and international inter-comparison exercise have been performed to validate the new methodology. (authors)

  15. Cochrane Rehabilitation Methodology Committee: an international survey of priorities for future work.

    Science.gov (United States)

    Levack, William M; Meyer, Thorsten; Negrini, Stefano; Malmivaara, Antti

    2017-10-01

    Cochrane Rehabilitation aims to improve the application of evidence-based practice in rehabilitation. It also aims to support Cochrane in the production of reliable, clinically meaningful syntheses of evidence related to the practice of rehabilitation, while accommodating the many methodological challenges facing the field. To this end, Cochrane Rehabilitation established a Methodology Committee to examine, explore and find solutions for the methodological challenges related to evidence synthesis and knowledge translation in rehabilitation. We conducted an international online survey via Cochrane Rehabilitation networks to canvass opinions regarding the future work priorities for this committee and to seek information on people's current capabilities to assist with this work. The survey findings indicated strongest interest in work on how reviewers have interpreted and applied Cochrane methods in reviews on rehabilitation topics in the past, and on gathering a collection of existing publications on review methods for undertaking systematic reviews relevant to rehabilitation. Many people are already interested in contributing to the work of the Methodology Committee and there is a large amount of expertise for this work in the extended Cochrane Rehabilitation network already.

  16. Can smartphones measure momentary quality of life and participation? A proof of concept using experience sampling surveys with university students.

    Science.gov (United States)

    Liddle, Jacki; Wishink, Anna; Springfield, Liz; Gustafsson, Louise; Ireland, David; Silburn, Peter

    2017-08-01

    Understanding quality of life and participation is a key aspect of occupational therapy research. The use of smartphones to deliver experience-sampling surveys may provide an accessible way to monitor these outcomes. This study used smartphone-based experience sampling methods (ESM) to investigate factors influencing momentary quality of life (mQOL) of university students. A convenience sample of students at an Australian university participated. Using a custom smartphone application, ESM surveys were sent six to eight times, every second day, over a week. Participants indicated their mQOL, occupational participation, occupational enjoyment, social context and location via surveys and provided demographic and health information in a single self-report questionnaire. The relationship between mQOL and variables was analysed at the survey level using logistic regression. Forty students completed 391 surveys. Higher mQOL was significantly related to participation in productive occupations (z = 3.48; P = 0.001), moderate (z = 4.00; P sample, analysing at the individual level, and using ESM in conjunction with other methodologies is recommended. © 2017 Occupational Therapy Australia.

  17. Methodology of Young Minds Matter: The second Australian Child and Adolescent Survey of Mental Health and Wellbeing.

    Science.gov (United States)

    Hafekost, Jennifer; Lawrence, David; Boterhoven de Haan, Katrina; Johnson, Sarah E; Saw, Suzy; Buckingham, William J; Sawyer, Michael G; Ainley, John; Zubrick, Stephen R

    2016-09-01

    To describe the study design of Young Minds Matter: The second Australian Child and Adolescent Survey of Mental Health and Wellbeing. The aims of the study, sample design, development of survey content, field procedures and final questionnaires are detailed. During 2013-2014, a national household survey of the mental health and wellbeing of young people was conducted involving a sample of 6310 families selected at random from across Australia. The survey included a face-to-face diagnostic interview with parents/carers of 4- to 17-year-olds and a self-report questionnaire completed by young people aged 11-17 years. The overall response rate to the survey was 55% with 6310 parents/carers of eligible households participating in the survey. In addition, 2967 or 89% of young people aged 11-17 years in these participating households completed a questionnaire. The survey sample was found to be broadly representative of the Australian population on major demographic characteristics when compared with data from the Census of Population and Housing. However, adjustments were made for an over-representation of younger children aged 4 to 7 years and also families with more than one eligible child in the household. Young Minds Matter provides updated national prevalence estimates of common child and adolescent mental disorders, describes patterns of service use and will help to guide future decisions in the development of policy and provision of mental health services for children and adolescents. Advancements in interviewing methodology, addition of a data linkage component and informed content development contributed to improved breadth and quality of the data collected. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  18. Statistical literacy and sample survey results

    Science.gov (United States)

    McAlevey, Lynn; Sullivan, Charles

    2010-10-01

    Sample surveys are widely used in the social sciences and business. The news media almost daily quote from them, yet they are widely misused. Using students with prior managerial experience embarking on an MBA course, we show that common sample survey results are misunderstood even by those managers who have previously done a statistics course. In general, they fare no better than managers who have never studied statistics. There are implications for teaching, especially in business schools, as well as for consulting.

  19. A survey of dynamic methodologies for probabilistic safety assessment of nuclear power plants

    International Nuclear Information System (INIS)

    Aldemir, Tunc

    2013-01-01

    Highlights: ► Dynamic methodologies for probabilistic safety assessment (PSA) are surveyed. ► These methodologies overcome the limitations of the traditional approach to PSA. ► They are suitable for PSA using a best estimate plus uncertainty approach. ► They are highly computation intensive and produce very large number of scenarios. ► Use of scenario clustering can assist the analysis of the results. -- Abstract: Dynamic methodologies for probabilistic safety assessment (PSA) are defined as those which use a time-dependent phenomenological model of system evolution along with its stochastic behavior to account for possible dependencies between failure events. Over the past 30 years, numerous concerns have been raised in the literature regarding the capability of the traditional static modeling approaches such as the event-tree/fault-tree methodology to adequately account for the impact of process/hardware/software/firmware/human interactions on the stochastic system behavior. A survey of the types of dynamic PSA methodologies proposed to date is presented, as well as a brief summary of an example application for the PSA modeling of a digital feedwater control system of an operating pressurized water reactor. The use of dynamic methodologies for PSA modeling of passive components and phenomenological uncertainties are also discussed.

  20. Sampling and Analysis Plan for Supplemental Environmental Project: Aquatic Life Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Berryhill, Jesse Tobias [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gaukler, Shannon Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-26

    As part of a settlement agreement for nuclear waste incidents in 2014, several supplemental environment projects (SEPs) were initiated at Los Alamos National Laboratory (LANL or the Laboratory) between the U.S. Department of Energy and the state of New Mexico. One SEP from this agreement consists of performing aquatic life surveys and will be used to assess the applicability of using generic ambient water-quality criteria (AWQC) for aquatic life. AWQC are generic criteria developed by the U.S. Environmental Protection Agency (EPA) to cover a broad range of aquatic species and are not unique to a specific region or state. AWQC are established by a composition of toxicity data, called species sensitivity distributions (SSDs), and are determined by LC50 (lethal concentration of 50% of the organisms studied) acute toxicity experiments for chemicals of interest. It is of interest to determine whether aquatic species inhabiting waters on the Pajarito Plateau are adequately protected using the current generic AWQC. The focus of this study will determine which aquatic species are present in ephemeral, intermittent, and perennial waters within LANL boundaries and from reference waters adjacent to LANL. If the species identified from these waters do not generally represent species used in the SSDs, then SSDs may need to be modified and AWQC may need to be updated. This sampling and analysis plan details the sampling methodology, surveillance locations, temporal scheduling, and analytical approaches that will be used to complete aquatic life surveys. A significant portion of this sampling and analysis plan was formalized by referring to Appendix E: SEP Aquatic Life Surveys DQO (Data Quality Objectives).

  1. Sample design for the residential energy consumption survey

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    The purpose of this report is to provide detailed information about the multistage area-probability sample design used for the Residential Energy Consumption Survey (RECS). It is intended as a technical report, for use by statisticians, to better understand the theory and procedures followed in the creation of the RECS sample frame. For a more cursory overview of the RECS sample design, refer to the appendix entitled ``How the Survey was Conducted,`` which is included in the statistical reports produced for each RECS survey year.

  2. Understanding Sample Surveys: Selective Learning about Social Science Research Methods

    Science.gov (United States)

    Currin-Percival, Mary; Johnson, Martin

    2010-01-01

    We investigate differences in what students learn about survey methodology in a class on public opinion presented in two critically different ways: with the inclusion or exclusion of an original research project using a random-digit-dial telephone survey. Using a quasi-experimental design and data obtained from pretests and posttests in two public…

  3. International conference on research methodology for roadside surveys of drinking-driving : alcohol countermeasures workshop

    Science.gov (United States)

    1974-09-01

    The basic purpose [of the conference] was to encourage more roadside surveys by furthering the research methodology and recommendations for conducting roadside surveys developed by a special group of the Organization for Economic Cooperation and Deve...

  4. Disordered Gambling Prevalence: Methodological Innovations in a General Danish Population Survey.

    Science.gov (United States)

    Harrison, Glenn W; Jessen, Lasse J; Lau, Morten I; Ross, Don

    2018-03-01

    We study Danish adult gambling behavior with an emphasis on discovering patterns relevant to public health forecasting and economic welfare assessment of policy. Methodological innovations include measurement of formative in addition to reflective constructs, estimation of prospective risk for developing gambling disorder rather than risk of being falsely negatively diagnosed, analysis with attention to sample weights and correction for sample selection bias, estimation of the impact of trigger questions on prevalence estimates and sample characteristics, and distinguishing between total and marginal effects of risk-indicating factors. The most significant novelty in our design is that nobody was excluded on the basis of their response to a 'trigger' or 'gateway' question about previous gambling history. Our sample consists of 8405 adult Danes. We administered the Focal Adult Gambling Screen to all subjects and estimate prospective risk for disordered gambling. We find that 87.6% of the population is indicated for no detectable risk, 5.4% is indicated for early risk, 1.7% is indicated for intermediate risk, 2.6% is indicated for advanced risk, and 2.6% is indicated for disordered gambling. Correcting for sample weights and controlling for sample selection has a significant effect on prevalence rates. Although these estimates of the 'at risk' fraction of the population are significantly higher than conventionally reported, we infer a significant decrease in overall prevalence rates of detectable risk with these corrections, since gambling behavior is positively correlated with the decision to participate in gambling surveys. We also find that imposing a threshold gambling history leads to underestimation of the prevalence of gambling problems.

  5. The quality of sample surveys in a developing nation

    Directory of Open Access Journals (Sweden)

    Paul A Bourne

    2010-08-01

    Full Text Available Paul A Bourne1, Christopher AD Charles2,3, Neva South-Bourne4, Chloe Morris1, Denise Eldemire-Shearer1, Maureen D Kerr-Campbell51Department of Community Health and Psychiatry, Faculty of Medical Sciences, University of the West Indies, Mona, Kingston, Jamaica; 2King Graduate School, Monroe College, Bronx, New York, USA; 3Center for Victim Support, Harlem Hospital Center, New York, USA; 4Research assistant for Paul A Bourne; 5Systems Development Unit, Main Library, Faculty of Humanities and Education, University of the West Indies, Mona, Kingston, JamaicaBackground: In Jamaica, population census began in 1844, and many intercensal ratios obtained from the census data showed that there is a general high degree of accuracy of the data. However, statistics from the Jamaican Ministry of Health showed that there are inaccuracies in health data collected from males using sample surveys.Objectives: The objectives of the present research are to 1 investigate the accuracy of a national sample survey, 2 explore the feasibility and quality of using a subnational sample survey to represent a national survey, 3 aid other scholars in understanding the probability of using national sample surveys and subnational sample surveys, 4 assess older men’s ­evaluation of their health status, and 5 determine whether dichotomization changes self-evaluated health status.Methods: For the current study, the data used in the analysis were originally collected from 2 different sources: 1 the Jamaica Survey of Living Conditions (JSLC and 2 Survey of Older Men (SOM. Cross validation of self-evaluated data of men in Jamaica was done with comparable samples of the complete JSLC data and the SOM data, where men older than 55 years were selected from each sample.Results: In study 1, 50.2% of respondents indicated at least good self-evaluated health status compared with 74.0% in study 2. Statistical associations were found between health status and survey sample (Χ2 [df = 5

  6. Sample design considerations of indoor air exposure surveys

    International Nuclear Information System (INIS)

    Cox, B.G.; Mage, D.T.; Immerman, F.W.

    1988-01-01

    Concern about the potential for indoor air pollution has prompted recent surveys of radon and NO 2 concentrations in homes and personal exposure studies of volatile organics, carbon monoxide and pesticides, to name a few. The statistical problems in designing sample surveys that measure the physical environment are diverse and more complicated than those encountered in traditional surveys of human attitudes and attributes. This paper addresses issues encountered when designing indoor air quality (IAQ) studies. General statistical concepts related to target population definition, frame creation, and sample selection for area household surveys and telephone surveys are presented. The implications of different measurement approaches are discussed, and response rate considerations are described

  7. 3-D SURVEY APPLIED TO INDUSTRIAL ARCHAEOLOGY BY TLS METHODOLOGY

    Directory of Open Access Journals (Sweden)

    M. Monego

    2017-05-01

    Full Text Available This work describes the three-dimensional survey of “Ex Stazione Frigorifera Specializzata”: initially used for agricultural storage, during the years it was allocated to different uses until the complete neglect. The historical relevance and the architectural heritage that this building represents has brought the start of a recent renovation project and functional restoration. In this regard it was necessary a global 3-D survey that was based on the application and integration of different geomatic methodologies (mainly terrestrial laser scanner, classical topography, and GNSS. The acquisitions of point clouds was performed using different laser scanners: with time of flight (TOF and phase shift technologies for the distance measurements. The topographic reference network, needed for scans alignment in the same system, was measured with a total station. For the complete survey of the building, 122 scans were acquired and 346 targets were measured from 79 vertices of the reference network. Moreover, 3 vertices were measured with GNSS methodology in order to georeference the network. For the detail survey of machine room were executed 14 scans with 23 targets. The 3-D global model of the building have less than one centimeter of error in the alignment (for the machine room the error in alignment is not greater than 6 mm and was used to extract products such as longitudinal and transversal sections, plans, architectural perspectives, virtual scans. A complete spatial knowledge of the building is obtained from the processed data, providing basic information for restoration project, structural analysis, industrial and architectural heritage valorization.

  8. The 2014 Survey on Living with Chronic Diseases in Canada on Mood and Anxiety Disorders: a methodological overview

    Directory of Open Access Journals (Sweden)

    S. O’Donnell

    2016-12-01

    Full Text Available Introduction: There is a paucity of information about the impact of mood and anxiety disorders on Canadians and the approaches used to manage them. To address this gap, the 2014 Survey on Living with Chronic Diseases in Canada–Mood and Anxiety Disorders Component (SLCDC-MA was developed. The purpose of this paper is to describe the methodology of the 2014 SLCDC-MA and examine the sociodemographic characteristics of the final sample. Methods: The 2014 SLCDC-MA is a cross-sectional follow-up survey that includes Canadians from the 10 provinces aged 18 years and older with mood and/or anxiety disorders diagnosed by a health professional that are expected to last, or have already lasted, six months or more. The survey was developed by the Public Health Agency of Canada (PHAC through an iterative, consultative process with Statistics Canada and external experts. Statistics Canada performed content testing, designed the sampling frame and strategies and collected and processed the data. PHAC used descriptive analyses to describe the respondents’ sociodemographic characteristics, produced nationally representative estimates using survey weights provided by Statistics Canada, and generated variance estimates using bootstrap methodology. Results: The final 2014 SLCDC-MA sample consists of a total of 3361 respondents (68.9% response rate. Among Canadian adults with mood and/or anxiety disorders, close to two-thirds (64% were female, over half (56% were married/in a common-law relationship and 60% obtained a post-secondary education. Most were young or middle-aged (85%, Canadian born (88%, of non-Aboriginal status (95%, and resided in an urban setting (82%. Household income was fairly evenly distributed between the adequacy quintiles; however, individuals were more likely to report a household income adequacy within the lowest (23% versus highest (17% quintile. Forty-five percent reported having a mood disorder only, 24% an anxiety disorder only and 31

  9. Monitoring HIV Testing in the United States: Consequences of Methodology Changes to National Surveys.

    Directory of Open Access Journals (Sweden)

    Michelle M Van Handel

    Full Text Available In 2011, the National Health Interview Survey (NHIS, an in-person household interview, revised the human immunodeficiency virus (HIV section of the survey and the Behavioral Risk Factor Surveillance System (BRFSS, a telephone-based survey, added cellphone numbers to its sampling frame. We sought to determine how these changes might affect assessment of HIV testing trends.We used linear regression with pairwise contrasts with 2003-2013 data from NHIS and BRFSS to compare percentages of persons aged 18-64 years who reported HIV testing in landline versus cellphone-only households before and after 2011, when NHIS revised its in-person questionnaire and BRFSS added cellphone numbers to its telephone-based sample.In NHIS, the percentage of persons in cellphone-only households increased 13-fold from 2003 to 2013. The percentage ever tested for HIV was 6%-10% higher among persons in cellphone-only than landline households. The percentage ever tested for HIV increased significantly from 40.2% in 2003 to 45.0% in 2010, but was significantly lower in 2011 (40.6% and 2012 (39.7%. In BRFSS, the percentage ever tested decreased significantly from 45.9% in 2003 to 40.2% in 2010, but increased to 42.9% in 2011 and 43.5% in 2013.HIV testing estimates were lower after NHIS questionnaire changes but higher after BRFSS methodology changes. Data before and after 2011 are not comparable, complicating assessment of trends.

  10. Challenges in dental statistics: survey methodology topics

    Directory of Open Access Journals (Sweden)

    Giuseppe Pizzo

    2013-12-01

    Full Text Available This paper gathers some contributions concerning survey methodology in dental research, as discussed during the first Workshop of the SISMEC STATDENT working group on statistical methods and applications in dentistry, held in Ancona on the 28th September 2011.The first contribution deals with the European Global Oral Health Indicators Development (EGOHID Project which proposed a comprehensive and standardized system of epidemiological tools (questionnaires and clinical forms for national data collection on oral health in Europe. The second contribution regards the design and conduct of trials to evaluate the clinical efficacy and safety of toothbrushes and mouthrinses. Finally, a flexible and effective tool used to trace dental age reference charts tailored to Italian children is presented.

  11. National sample survey to assess the new case disease burden of leprosy in India

    Directory of Open Access Journals (Sweden)

    Kiran Katoch

    2017-01-01

    Full Text Available A national sample survey of leprosy was undertaken in partnership with Indian Council of Medical Research (ICMR institutions, National Leprosy Eradication Programme (NLEP, Panchayati Raj members, and treated leprosy patients to detect new cases of leprosy in India. The objectives of the survey were to estimate the new leprosy case load; record both Grade 1 and Grade 2 disabilities in the new cases; and to assess the magnitude of stigma and discrimination prevalent in the society. A cluster based, cross-sectional survey involving all States was used for the door-to-door survey using inverse sampling methodology. Rural and urban clusters were sampled separately. The population screened for detecting 28 new cases in rural and 30 in urban clusters was enumerated, recorded and analyzed. Data capture and analysis in different schedules were the main tools used. For quality control three tiers of experts were utilized for the confirmation of cases and disabilities. Self-stigma was assessed in more than half of the total new patients detected with disabilities by the approved questionnaire. A different questionnaire was used to assess the stigma in the community. A population of 14,725,525 (10,302,443 rural; 4,423,082 urban was screened and 2161 new cases - 1300 paucibacillary (PB and 861 multibacillary (MB were detected. New case estimates for leprosy was 330,346 (95% Confidence limits, 287,445-380,851. Disabilities observed in these cases were 2.05/100,000 population and 13.9 per cent (302/2161 in new cases. Self-stigma in patients with disabilities was reduced, and the patients were well accepted by the spouse, neighbour, at workplace and in social functions.

  12. The U-tube sampling methodology and real-time analysis of geofluids

    International Nuclear Information System (INIS)

    Freifeld, Barry; Perkins, Ernie; Underschultz, James; Boreham, Chris

    2009-01-01

    The U-tube geochemical sampling methodology, an extension of the porous cup technique proposed by Wood (1973), provides minimally contaminated aliquots of multiphase fluids from deep reservoirs and allows for accurate determination of dissolved gas composition. The initial deployment of the U-tube during the Frio Brine Pilot CO 2 storage experiment, Liberty County, Texas, obtained representative samples of brine and supercritical CO 2 from a depth of 1.5 km. A quadrupole mass spectrometer provided real-time analysis of dissolved gas composition. Since the initial demonstration, the U-tube has been deployed for (1) sampling of fluids down gradient of the proposed Yucca Mountain High-Level Waste Repository, Armagosa Valley, Nevada (2) acquiring fluid samples beneath permafrost in Nunuvut Territory, Canada, and (3) at a CO 2 storage demonstration project within a depleted gas reservoir, Otway Basin, Victoria, Australia. The addition of in-line high-pressure pH and EC sensors allows for continuous monitoring of fluid during sample collection. Difficulties have arisen during U-tube sampling, such as blockage of sample lines from naturally occurring waxes or from freezing conditions; however, workarounds such as solvent flushing or heating have been used to address these problems. The U-tube methodology has proven to be robust, and with careful consideration of the constraints and limitations, can provide high quality geochemical samples.

  13. Can Weighting Compensate for Sampling Issues in Internet Surveys?

    NARCIS (Netherlands)

    Vaske, J.J.; Jacobs, M.H.; Sijtsma, M.T.J.; Beaman, J.

    2011-01-01

    While Internet surveys have increased in popularity, results may not be representative of target populations. Weighting is commonly used to compensate for sampling issues. This article compared two surveys conducted in the Netherlands—a random mail survey (n = 353) and a convenience Internet survey

  14. Sample Size Calculations for Population Size Estimation Studies Using Multiplier Methods With Respondent-Driven Sampling Surveys.

    Science.gov (United States)

    Fearon, Elizabeth; Chabata, Sungai T; Thompson, Jennifer A; Cowan, Frances M; Hargreaves, James R

    2017-09-14

    While guidance exists for obtaining population size estimates using multiplier methods with respondent-driven sampling surveys, we lack specific guidance for making sample size decisions. To guide the design of multiplier method population size estimation studies using respondent-driven sampling surveys to reduce the random error around the estimate obtained. The population size estimate is obtained by dividing the number of individuals receiving a service or the number of unique objects distributed (M) by the proportion of individuals in a representative survey who report receipt of the service or object (P). We have developed an approach to sample size calculation, interpreting methods to estimate the variance around estimates obtained using multiplier methods in conjunction with research into design effects and respondent-driven sampling. We describe an application to estimate the number of female sex workers in Harare, Zimbabwe. There is high variance in estimates. Random error around the size estimate reflects uncertainty from M and P, particularly when the estimate of P in the respondent-driven sampling survey is low. As expected, sample size requirements are higher when the design effect of the survey is assumed to be greater. We suggest a method for investigating the effects of sample size on the precision of a population size estimate obtained using multipler methods and respondent-driven sampling. Uncertainty in the size estimate is high, particularly when P is small, so balancing against other potential sources of bias, we advise researchers to consider longer service attendance reference periods and to distribute more unique objects, which is likely to result in a higher estimate of P in the respondent-driven sampling survey. ©Elizabeth Fearon, Sungai T Chabata, Jennifer A Thompson, Frances M Cowan, James R Hargreaves. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 14.09.2017.

  15. The ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES) . I. Project description, survey sample, and quality assessment

    Science.gov (United States)

    Cox, Nick L. J.; Cami, Jan; Farhang, Amin; Smoker, Jonathan; Monreal-Ibero, Ana; Lallement, Rosine; Sarre, Peter J.; Marshall, Charlotte C. M.; Smith, Keith T.; Evans, Christopher J.; Royer, Pierre; Linnartz, Harold; Cordiner, Martin A.; Joblin, Christine; van Loon, Jacco Th.; Foing, Bernard H.; Bhatt, Neil H.; Bron, Emeric; Elyajouri, Meriem; de Koter, Alex; Ehrenfreund, Pascale; Javadi, Atefeh; Kaper, Lex; Khosroshadi, Habib G.; Laverick, Mike; Le Petit, Franck; Mulas, Giacomo; Roueff, Evelyne; Salama, Farid; Spaans, Marco

    2017-10-01

    The carriers of the diffuse interstellar bands (DIBs) are largely unidentified molecules ubiquitously present in the interstellar medium (ISM). After decades of study, two strong and possibly three weak near-infrared DIBs have recently been attributed to the C60^+ fullerene based on observational and laboratory measurements. There is great promise for the identification of the over 400 other known DIBs, as this result could provide chemical hints towards other possible carriers. In an effort tosystematically study the properties of the DIB carriers, we have initiated a new large-scale observational survey: the ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES). The main objective is to build on and extend existing DIB surveys to make a major step forward in characterising the physical and chemical conditions for a statistically significant sample of interstellar lines-of-sight, with the goal to reverse-engineer key molecular properties of the DIB carriers. EDIBLES is a filler Large Programme using the Ultraviolet and Visual Echelle Spectrograph at the Very Large Telescope at Paranal, Chile. It is designed to provide an observationally unbiased view of the presence and behaviour of the DIBs towards early-spectral-type stars whose lines-of-sight probe the diffuse-to-translucent ISM. Such a complete dataset will provide a deep census of the atomic and molecular content, physical conditions, chemical abundances and elemental depletion levels for each sightline. Achieving these goals requires a homogeneous set of high-quality data in terms of resolution (R 70 000-100 000), sensitivity (S/N up to 1000 per resolution element), and spectral coverage (305-1042 nm), as well as a large sample size (100+ sightlines). In this first paper the goals, objectives and methodology of the EDIBLES programme are described and an initial assessment of the data is provided.

  16. On Survey Data Analysis in Corporate Finance

    OpenAIRE

    Serita, Toshio

    2008-01-01

    Recently, survey data analysis has emerged as a new method for testing hypotheses andfor clarifying the relative importance of different factors in corporate finance decisions. This paper investigates the advantages and drawbacks of survey data analysis, methodology of survey data analysis such as questionnaire design, and analytical methods for survey data, incomparison with traditional large sample analysis. We show that survey data analysis does not replace traditional large sample analysi...

  17. Air sampling system for airborne surveys

    International Nuclear Information System (INIS)

    Jupiter, C.; Tipton, W.J.

    1975-01-01

    An air sampling system has been designed for installation on the Beechcraft King Air A-100 aircraft as a part of the Aerial Radiological Measuring System (ARMS). It is intended for both particle and whole gas sampling. The sampling probe is designed for isokinetic sampling and is mounted on a removable modified escape hatch cover, behind the co-pilot's seat, and extends about two feet forward of the hatch cover in the air stream lines. Directly behind the sampling probe inside the modified hatch cover is an expansion chamber, space for a 5-inch diameter filter paper cassette, and an optional four-stage cascade impactor for particle size distribution measurements. A pair of motors and blower pumps provide the necessary 0.5 atmosphere pressure across the type MSA 1106 B glass fiber filter paper to allow a flow rate of 50 cfm. The MSA 1106 B filter paper is designed to trap sub-micrometer particles with a high efficiency; it was chosen to enable a quantitative measurement of airborne radon daughters, one of the principal sources of background signals when radiological surveys are being performed. A venturi section and pressure gauges allow air flow rate measurements so that airborne contaminant concentrations may be quantified. A whole gas sampler capable of sampling a cubic meter of air is mounted inside the aircraft cabin. A nuclear counting system on board the aircraft provides capability for α, β and γ counting of filter paper samples. Design data are presented and types of survey missions which may be served by this system are described

  18. Methodology of the fasting sub-sample from the Mexican Health Survey, 2000 Metodología de la submuestra de suero de la Encuesta Nacional de Salud 2000

    OpenAIRE

    Simón Barquera; Citlalli Carrión; Ismael Campos; Juan Espinosa; Juan Rivera; Gustavo Olaiz-Fernández

    2007-01-01

    OBJECTIVE: To report the comparative results of the sub-sample of fasting adults selected for the biochemical measurement of cardiovascular risk factors and the rest of the Mexican Health Survey (MHS) (2000) participants. MATERIAL AND METHODS: The nationally representative, cross-sectional Mexican Health Survey (2000) was analyzed. Survey participants reporting a fasting state period of 9- to 12-h were included in a sub-sample (n= 2 535) and compared with all other participants (n= 41 126). P...

  19. Tobacco smoking surveillance: is quota sampling an efficient tool for monitoring national trends? A comparison with a random cross-sectional survey.

    Directory of Open Access Journals (Sweden)

    Romain Guignard

    Full Text Available OBJECTIVES: It is crucial for policy makers to monitor the evolution of tobacco smoking prevalence. In France, this monitoring is based on a series of cross-sectional general population surveys, the Health Barometers, conducted every five years and based on random samples. A methodological study has been carried out to assess the reliability of a monitoring system based on regular quota sampling surveys for smoking prevalence. DESIGN / OUTCOME MEASURES: In 2010, current and daily tobacco smoking prevalences obtained in a quota survey on 8,018 people were compared with those of the 2010 Health Barometer carried out on 27,653 people. Prevalences were assessed separately according to the telephone equipment of the interviewee (landline phone owner vs "mobile-only", and logistic regressions were conducted in the pooled database to assess the impact of the telephone equipment and of the survey mode on the prevalences found. Finally, logistic regressions adjusted for sociodemographic characteristics were conducted in the random sample in order to determine the impact of the needed number of calls to interwiew "hard-to-reach" people on the prevalence found. RESULTS: Current and daily prevalences were higher in the random sample (respectively 33.9% and 27.5% in 15-75 years-old than in the quota sample (respectively 30.2% and 25.3%. In both surveys, current and daily prevalences were lower among landline phone owners (respectively 31.8% and 25.5% in the random sample and 28.9% and 24.0% in the quota survey. The required number of calls was slightly related to the smoking status after adjustment for sociodemographic characteristics. CONCLUSION: Random sampling appears to be more effective than quota sampling, mainly by making it possible to interview hard-to-reach populations.

  20. Non-response weighting adjustment approach in survey sampling ...

    African Journals Online (AJOL)

    Hence the discussion is illustrated with real examples from surveys (in particular 2003 KDHS) conducted by Central Bureau of Statistics (CBS) - Kenya. Some suggestions are made for improving the quality of non-response weighting. Keywords: Survey non-response; non-response adjustment factors; weighting; sampling ...

  1. A Survey of Archaeological Samples Dated in 1985

    DEFF Research Database (Denmark)

    Mejdahl, Vagn

    1986-01-01

    A survey is given of archaeological samples received for dating in 1985 at the Nordic Laboratory for Thermoluminescence Dating. A total of 66 samples were dated, 42 of which were burnt stones. All results were corrected for short-term fading as measured for samples stored at room temperature...

  2. A Survey of Archaeological Samples Dated in 1984

    DEFF Research Database (Denmark)

    Mejdahl, Vagn

    A survey is given of archaeological samples dated in 1984 at the Nordic Laboratory for Thermoluminescence Dating. A total of 79 samples were dated, 49 of which were burnt stones. All results were corrected for fading as measured for samples stored for four weeks at room temperature. The alpha dose...

  3. Utility Estimation for Pediatric Vesicoureteral Reflux: Methodological Considerations Using an Online Survey Platform.

    Science.gov (United States)

    Tejwani, Rohit; Wang, Hsin-Hsiao S; Lloyd, Jessica C; Kokorowski, Paul J; Nelson, Caleb P; Routh, Jonathan C

    2017-03-01

    The advent of online task distribution has opened a new avenue for efficiently gathering community perspectives needed for utility estimation. Methodological consensus for estimating pediatric utilities is lacking, with disagreement over whom to sample, what perspective to use (patient vs parent) and whether instrument induced anchoring bias is significant. We evaluated what methodological factors potentially impact utility estimates for vesicoureteral reflux. Cross-sectional surveys using a time trade-off instrument were conducted via the Amazon Mechanical Turk® (https://www.mturk.com) online interface. Respondents were randomized to answer questions from child, parent or dyad perspectives on the utility of a vesicoureteral reflux health state and 1 of 3 "warm-up" scenarios (paralysis, common cold, none) before a vesicoureteral reflux scenario. Utility estimates and potential predictors were fitted to a generalized linear model to determine what factors most impacted utilities. A total of 1,627 responses were obtained. Mean respondent age was 34.9 years. Of the respondents 48% were female, 38% were married and 44% had children. Utility values were uninfluenced by child/personal vesicoureteral reflux/urinary tract infection history, income or race. Utilities were affected by perspective and were higher in the child group (34% lower in parent vs child, p pediatric conditions. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Effect of passive acoustic sampling methodology on detecting bats after declines from white nose syndrome

    Science.gov (United States)

    Coleman, Laci S.; Ford, W. Mark; Dobony, Christopher A.; Britzke, Eric R.

    2014-01-01

    Concomitant with the emergence and spread of white-nose syndrome (WNS) and precipitous decline of many bat species in North America, natural resource managers need modified and/or new techniques for bat inventory and monitoring that provide robust occupancy estimates. We used Anabat acoustic detectors to determine the most efficient passive acoustic sampling design for optimizing detection probabilities of multiple bat species in a WNS-impacted environment in New York, USA. Our sampling protocol included: six acoustic stations deployed for the entire duration of monitoring as well as a 4 x 4 grid and five transects of 5-10 acoustic units that were deployed for 6-8 night sample durations surveyed during the summers of 2011-2012. We used Program PRESENCE to determine detection probability and site occupancy estimates. Overall, the grid produced the highest detection probabilities for most species because it contained the most detectors and intercepted the greatest spatial area. However, big brown bats (Eptesicus fuscus) and species not impacted by WNS were detected easily regardless of sampling array. Endangered Indiana (Myotis sodalis) and little brown (Myotis lucifugus) and tri-colored bats (Perimyotis subflavus) showed declines in detection probabilities over our study, potentially indicative of continued WNS-associated declines. Identification of species presence through efficient methodologies is vital for future conservation efforts as bat populations decline further due to WNS and other factors.   

  5. Transuranium analysis methodologies for biological and environmental samples

    International Nuclear Information System (INIS)

    Wessman, R.A.; Lee, K.D.; Curry, B.; Leventhal, L.

    1978-01-01

    Analytical procedures for the most abundant transuranium nuclides in the environment (i.e., plutonium and, to a lesser extent, americium) are available. There is a lack of procedures for doing sequential analysis for Np, Pu, Am, and Cm in environmental samples, primarily because of current emphasis on Pu and Am. Reprocessing requirements and waste disposal connected with the fuel cycle indicate that neptunium and curium must be considered in environmental radioactive assessments. Therefore it was necessary to develop procedures that determine all four of these radionuclides in the environment. The state of the art of transuranium analysis methodology as applied to environmental samples is discussed relative to different sample sources, such as soil, vegetation, air, water, and animals. Isotope-dilution analysis with 243 Am ( 239 Np) and 236 Pu or 242 Pu radionuclide tracers is used. Americium and curium are analyzed as a group, with 243 Am as the tracer. Sequential extraction procedures employing bis(2-ethyl-hexyl)orthophosphoric acid (HDEHP) were found to result in lower yields and higher Am--Cm fractionation than ion-exchange methods

  6. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys

    OpenAIRE

    Hund, Lauren; Bedrick, Edward J.; Pagano, Marcello

    2015-01-01

    Lot quality assurance sampling (LQAS) surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we comp...

  7. Methodological studies for long range environmental gamma rate survey in Brazil

    International Nuclear Information System (INIS)

    Souza, Elder M.; Wasserman, Maria Angelica V.; Rochedo, Elaine R. R.

    2009-01-01

    The objective of this work is to support the establishment of a methodology for gamma radiation survey over large areas in order to estimate public exposure to natural background radiation in Brazil. In a first stage, two different sites close to large water bodies were chosen, Guanabara Bay, RJ and Amazon River close to Santarem, PA. Early results showed similar results for over water surveys despite the type of water body. Dose rates over land are higher than those over water, due to the natural radioactivity on soil, pavements and other building materials. In this study the focus was on variability of measurements performed in the same area and variability for different types of area, including roads and urbanized environments. Several measurements have been performed of several areas, that included roads and towns in Para, Bahia, Rio de Janeiro and Minas Gerais. Measurements were done by car and on boats, using a AT6101C Scanner - Spectral Radiation Scanner. Differences were detected for different areas, with roads generally presenting lower dose rates than highly urbanized areas. Also, for roads close to granite rocks and mountains, dose rates are higher than those at both coastal areas and inland lowlands. Large towns present large variability, with individual measurements close to average dose rates from anomalous uranium sites. The results will be used to derive a methodology for assessing background radiation exposure for the Brazilian population. It can be concluded that surveys are to be based on population distribution grids rather than on a simple area based grid distribution, due to both the uneven population distribution and the variability on external dose rates throughout the Brazilian territory. (author)

  8. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    DEFF Research Database (Denmark)

    Edjabou, Vincent Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona

    2015-01-01

    Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both...... comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub......-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10-50 waste fractions, organised according to a three-level (tiered approach) facilitating,comparison of the waste data between individual sub-areas with different fractionation (waste...

  9. Bibliographic survey on methodologies for development of health database of the population in case of cancer occurrences

    International Nuclear Information System (INIS)

    Cavinato, Christianne C.; Andrade, Delvonei A. de; Sabundjian, Gaiane; Diz, Maria Del Pilar E.

    2014-01-01

    The objective is to make a survey of existing methodologies and for the development of public health database, focusing on health (fatal and nonfatal cancer) of the population surrounding a nuclear facility, for purposes of calculating the environmental cost of the same. From methodologies found to develop this type of database, a methodology will be developed to be applied to the internal public of IPEN/CNEN-SP, Brazil, as a pre-test for the acquisition of health information desired

  10. U.S. Geological Survey Methodology Development for Ecological Carbon Assessment and Monitoring

    Science.gov (United States)

    Zhu, Zhi-Liang; Stackpoole, S.M.

    2009-01-01

    Ecological carbon sequestration refers to transfer and storage of atmospheric carbon in vegetation, soils, and aquatic environments to help offset the net increase from carbon emissions. Understanding capacities, associated opportunities, and risks of vegetated ecosystems to sequester carbon provides science information to support formulation of policies governing climate change mitigation, adaptation, and land-management strategies. Section 712 of the Energy Independence and Security Act (EISA) of 2007 mandates the Department of the Interior to develop a methodology and assess the capacity of our nation's ecosystems for ecological carbon sequestration and greenhouse gas (GHG) flux mitigation. The U.S. Geological Survey (USGS) LandCarbon Project is responding to the Department of Interior's request to develop a methodology that meets specific EISA requirements.

  11. Use of Lot quality assurance sampling surveys to evaluate community health worker performance in rural Zambia: a case of Luangwa district.

    Science.gov (United States)

    Mwanza, Moses; Zulu, Japhet; Topp, Stephanie M; Musonda, Patrick; Mutale, Wilbroad; Chilengi, Roma

    2017-04-17

    The Better Health Outcomes through Mentoring and Assessment (BHOMA) project is a cluster randomized controlled trial aimed at reducing age-standardized mortality rates in three rural districts through involvement of Community Health Workers (CHWs), Traditional Birth Attendants (TBAs), and Neighborhood Health Committees (NHCs). CHWs conduct quarterly surveys on all households using a questionnaire that captures key health events occurring within their catchment population. In order to validate contact with households, we utilize the Lot Quality Assurance Sampling (LQAS) methodology. In this study, we report experiences of applying the LQAS approach to monitor performance of CHWs in Luangwa District. Between April 2011 and December 2013, seven health facilities in Luangwa district were enrolled into the BHOMA project. The health facility catchment areas were divided into 33 geographic zones. Quality assurance was performed each quarter by randomly selecting zones representing about 90% of enrolled catchment areas from which 19 households per zone where also randomly identified. The surveys were conducted by CHW supervisors who had been trained on using the LQAS questionnaire. Information collected included household identity number (ID), whether the CHW visited the household, duration of the most recent visit, and what health information was discussed during the CHW visit. The threshold for success was set at 75% household outreach by CHWs in each zone. There are 4,616 total households in the 33 zones. This yielded a target of 32,212 household visits by community health workers during the 7 survey rounds. Based on the set cutoff point for passing the surveys (at least 75% households confirmed as visited), only one team of CHWs at Luangwa high school failed to reach the target during round 1 of the surveys; all the teams otherwise registered successful visits in all the surveys. We have employed the LQAS methodology for assurance that quarterly surveys were

  12. Biomass Thermogravimetric Analysis: Uncertainty Determination Methodology and Sampling Maps Generation

    Science.gov (United States)

    Pazó, Jose A.; Granada, Enrique; Saavedra, Ángeles; Eguía, Pablo; Collazo, Joaquín

    2010-01-01

    The objective of this study was to develop a methodology for the determination of the maximum sampling error and confidence intervals of thermal properties obtained from thermogravimetric analysis (TG), including moisture, volatile matter, fixed carbon and ash content. The sampling procedure of the TG analysis was of particular interest and was conducted with care. The results of the present study were compared to those of a prompt analysis, and a correlation between the mean values and maximum sampling errors of the methods were not observed. In general, low and acceptable levels of uncertainty and error were obtained, demonstrating that the properties evaluated by TG analysis were representative of the overall fuel composition. The accurate determination of the thermal properties of biomass with precise confidence intervals is of particular interest in energetic biomass applications. PMID:20717532

  13. Emigration Rates From Sample Surveys: An Application to Senegal.

    Science.gov (United States)

    Willekens, Frans; Zinn, Sabine; Leuchter, Matthias

    2017-12-01

    What is the emigration rate of a country, and how reliable is that figure? Answering these questions is not at all straightforward. Most data on international migration are census data on foreign-born population. These migrant stock data describe the immigrant population in destination countries but offer limited information on the rate at which people leave their country of origin. The emigration rate depends on the number leaving in a given period and the population at risk of leaving, weighted by the duration at risk. Emigration surveys provide a useful data source for estimating emigration rates, provided that the estimation method accounts for sample design. In this study, emigration rates and confidence intervals are estimated from a sample survey of households in the Dakar region in Senegal, which was part of the Migration between Africa and Europe survey. The sample was a stratified two-stage sample with oversampling of households with members abroad or return migrants. A combination of methods of survival analysis (time-to-event data) and replication variance estimation (bootstrapping) yields emigration rates and design-consistent confidence intervals that are representative for the study population.

  14. A Survey of Blue-Noise Sampling and Its Applications

    KAUST Repository

    Yan, Dongming; Guo, Jian-Wei; Wang, Bin; Zhang, Xiao-Peng; Wonka, Peter

    2015-01-01

    In this paper, we survey recent approaches to blue-noise sampling and discuss their beneficial applications. We discuss the sampling algorithms that use points as sampling primitives and classify the sampling algorithms based on various aspects, e.g., the sampling domain and the type of algorithm. We demonstrate several well-known applications that can be improved by recent blue-noise sampling techniques, as well as some new applications such as dynamic sampling and blue-noise remeshing.

  15. A Survey of Blue-Noise Sampling and Its Applications

    KAUST Repository

    Yan, Dongming

    2015-05-05

    In this paper, we survey recent approaches to blue-noise sampling and discuss their beneficial applications. We discuss the sampling algorithms that use points as sampling primitives and classify the sampling algorithms based on various aspects, e.g., the sampling domain and the type of algorithm. We demonstrate several well-known applications that can be improved by recent blue-noise sampling techniques, as well as some new applications such as dynamic sampling and blue-noise remeshing.

  16. A Study on the Representative Sampling Survey for Radionuclide Analysis of RI Waste

    Energy Technology Data Exchange (ETDEWEB)

    Jee, K. Y. [KAERI, Daejeon (Korea, Republic of); Kim, Juyoul; Jung, Gunhyo [FNC Tech. Co., Daejeon (Korea, Republic of)

    2007-07-15

    We developed a quantitative method for attaining a representative sample during sampling survey of RI waste. Considering a source, process, and type of RI waste, the method computes the number of sample, confidence interval, variance, and coefficient of variance. We also systematize the method of sampling survey logically and quantitatively. The result of this study can be applied to sampling survey of low- and intermediate-level waste generated from nuclear power plant during the transfer process to disposal facility.

  17. Are marketed topical metronidazole creams bioequivalent? Evaluation by in vivo microdialysis sampling and tape stripping methodology

    DEFF Research Database (Denmark)

    Garcia Ortiz, Patricia Elodia; Hansen, S H; Shah, Surendra P.

    2011-01-01

    To evaluate the bioequivalence of 3 marketed topical metronidazole formulations by simultaneous dermal microdialysis and stratum corneum sampling by the tape stripping methodology, and to compare the techniques as tools for the determination of bioequivalence.......To evaluate the bioequivalence of 3 marketed topical metronidazole formulations by simultaneous dermal microdialysis and stratum corneum sampling by the tape stripping methodology, and to compare the techniques as tools for the determination of bioequivalence....

  18. Study of adolescents exposed in utero. Methodological evaluation of the Nagasaki sample

    Energy Technology Data Exchange (ETDEWEB)

    Hrubec, Zdenek, Noble, K.B.; Burrow, G N

    1962-09-12

    Fetal tissues have been shown to be extremely sensitive to ionizing radiation, and therefore a group of children who were exposed in utero are of special interest. When these children entered adolescence, an intensive study was undertaken to determine whether differences not otherwise apparent would be revealed during the stress of this period of rapid growth. The purpose of this report is to describe the sample used to study these adolescent children who were exposed in utero and to provide reference information. The problems of using ex post facto methods as employed in this study have been discussed in detail elsewhere. In summary, the extent to which findings of a retrospective study may be generalized to a larger population can be determined only from a careful and extensive study of the characteristics of the sample and an evaluation of the procedures used in its selection. It is generally recognized that even an extensive methodologic exploration of this kind offers no conclusive proof that a sample is useful for a specific study. In the sample, some variables which may have a considerable effect on the medical data, such as socioeconomic status, have been taken into account only superficially. There is always the possibility that some important, completely unsuspected variables may produce spurious associations. However there is an almost infinite number of such factors which might conceivably affect the data. Vast research resources could be committed to a methodologic evaluation without fulfilling the basic purpose of the study. An approach must be devised which is judged methodologically adequate but which will not tax the research resource to the detriment of the basic objectives. It is hoped that this report will satisfy the requirements of this compromise. 30 references, 36 tables.

  19. THE BOSS EMISSION-LINE LENS SURVEY (BELLS). I. A LARGE SPECTROSCOPICALLY SELECTED SAMPLE OF LENS GALAXIES AT REDSHIFT {approx}0.5

    Energy Technology Data Exchange (ETDEWEB)

    Brownstein, Joel R.; Bolton, Adam S.; Pandey, Parul [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schlegel, David J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Eisenstein, Daniel J. [Harvard College Observatory, 60 Garden Street, MS 20, Cambridge, MA 02138 (United States); Kochanek, Christopher S. [Department of Astronomy and Center for Cosmology and Astroparticle Physics, Ohio State University, Columbus, OH 43210 (United States); Connolly, Natalia [Department of Physics, Hamilton College, Clinton, NY 13323 (United States); Maraston, Claudia [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom); Seitz, Stella [University Observatory Munich, Scheinstrasse 1, 81679 Muenchen (Germany); Wake, David A. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Wood-Vasey, W. Michael [Pittsburgh Center for Particle Physics, Astrophysics, and Cosmology (PITT-PACC), Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Brinkmann, Jon [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, Pennsylvania State University, University Park, PA 16802 (United States); Weaver, Benjamin A. [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

    2012-01-01

    We present a catalog of 25 definite and 11 probable strong galaxy-galaxy gravitational lens systems with lens redshifts 0.4 {approx}< z {approx}< 0.7, discovered spectroscopically by the presence of higher-redshift emission lines within the Baryon Oscillation Spectroscopic Survey (BOSS) of luminous galaxies, and confirmed with high-resolution Hubble Space Telescope (HST) images of 44 candidates. Our survey extends the methodology of the Sloan Lens Advanced Camera for Surveys survey (SLACS) to higher redshift. We describe the details of the BOSS spectroscopic candidate detections, our HST ACS image processing and analysis methods, and our strong gravitational lens modeling procedure. We report BOSS spectroscopic parameters and ACS photometric parameters for all candidates, and mass-distribution parameters for the best-fit singular isothermal ellipsoid models of definite lenses. Our sample to date was selected using only the first six months of BOSS survey-quality spectroscopic data. The full five-year BOSS database should produce a sample of several hundred strong galaxy-galaxy lenses and in combination with SLACS lenses at lower redshift, strongly constrain the redshift evolution of the structure of elliptical, bulge-dominated galaxies as a function of luminosity, stellar mass, and rest-frame color, thereby providing a powerful test for competing theories of galaxy formation and evolution.

  20. A cross-sectional survey of 5-year-old children with non-syndromic unilateral cleft lip and palate: the Cleft Care UK study. Part 1: background and methodology

    Science.gov (United States)

    Persson, M; Sandy, J R; Waylen, A; Wills, A K; Al-Ghatam, R; Ireland, A J; Hall, A J; Hollingworth, W; Jones, T; Peters, T J; Preston, R; Sell, D; Smallridge, J; Worthington, H; Ness, A R

    2015-01-01

    Structured Abstract Objectives We describe the methodology for a major study investigating the impact of reconfigured cleft care in the United Kingdom (UK) 15 years after an initial survey, detailed in the Clinical Standards Advisory Group (CSAG) report in 1998, had informed government recommendations on centralization. Setting and Sample Population This is a UK multicentre cross-sectional study of 5-year-olds born with non-syndromic unilateral cleft lip and palate. Children born between 1 April 2005 and 31 March 2007 were seen in cleft centre audit clinics. Materials and Methods Consent was obtained for the collection of routine clinical measures (speech recordings, hearing, photographs, models, oral health, psychosocial factors) and anthropometric measures (height, weight, head circumference). The methodology for each clinical measure followed those of the earlier survey as closely as possible. Results We identified 359 eligible children and recruited 268 (74.7%) to the study. Eleven separate records for each child were collected at the audit clinics. In total, 2666 (90.4%) were collected from a potential 2948 records. The response rates for the self-reported questionnaires, completed at home, were 52.6% for the Health and Lifestyle Questionnaire and 52.2% for the Satisfaction with Service Questionnaire. Conclusions Response rates and measures were similar to those achieved in the previous survey. There are practical, administrative and methodological challenges in repeating cross-sectional surveys 15 years apart and producing comparable data. PMID:26567851

  1. Synthesizing exoplanet demographics from radial velocity and microlensing surveys. I. Methodology

    International Nuclear Information System (INIS)

    Clanton, Christian; Gaudi, B. Scott

    2014-01-01

    Motivated by the order of magnitude difference in the frequency of giant planets orbiting M dwarfs inferred by microlensing and radial velocity (RV) surveys, we present a method for comparing the statistical constraints on exoplanet demographics inferred from these methods. We first derive the mapping from the observable parameters of a microlensing-detected planet to those of an analogous planet orbiting an RV-monitored star. Using this mapping, we predict the distribution of RV observables for the planet population inferred from microlensing surveys, taking care to adopt reasonable priors for, and properly marginalize over, the unknown physical parameters of microlensing-detected systems. Finally, we use simple estimates of the detection limits for a fiducial RV survey to predict the number and properties of analogs of the microlensing planet population such an RV survey should detect. We find that RV and microlensing surveys have some overlap, specifically for super-Jupiter mass planets (m p ≳ 1 M Jup ) with periods between ∼3-10 yr. However, the steeply falling planetary mass function inferred from microlensing implies that, in this region of overlap, RV surveys should infer a much smaller frequency than the overall giant planet frequency (m p ≳ 0.1 M Jup ) inferred by microlensing. Our analysis demonstrates that it is possible to statistically compare and synthesize data sets from multiple exoplanet detection techniques in order to infer exoplanet demographics over wider regions of parameter space than are accessible to individual methods. In a companion paper, we apply our methodology to several representative microlensing and RV surveys to derive the frequency of planets around M dwarfs with orbits of ≲ 30 yr.

  2. Finding needles in a haystack: a methodology for identifying and sampling community-based youth smoking cessation programs.

    Science.gov (United States)

    Emery, Sherry; Lee, Jungwha; Curry, Susan J; Johnson, Tim; Sporer, Amy K; Mermelstein, Robin; Flay, Brian; Warnecke, Richard

    2010-02-01

    Surveys of community-based programs are difficult to conduct when there is virtually no information about the number or locations of the programs of interest. This article describes the methodology used by the Helping Young Smokers Quit (HYSQ) initiative to identify and profile community-based youth smoking cessation programs in the absence of a defined sample frame. We developed a two-stage sampling design, with counties as the first-stage probability sampling units. The second stage used snowball sampling to saturation, to identify individuals who administered youth smoking cessation programs across three economic sectors in each county. Multivariate analyses modeled the relationship between program screening, eligibility, and response rates and economic sector and stratification criteria. Cumulative logit models analyzed the relationship between the number of contacts in a county and the number of programs screened, eligible, or profiled in a county. The snowball process yielded 9,983 unique and traceable contacts. Urban and high-income counties yielded significantly more screened program administrators; urban counties produced significantly more eligible programs, but there was no significant association between the county characteristics and program response rate. There is a positive relationship between the number of informants initially located and the number of programs screened, eligible, and profiled in a county. Our strategy to identify youth tobacco cessation programs could be used to create a sample frame for other nonprofit organizations that are difficult to identify due to a lack of existing directories, lists, or other traditional sample frames.

  3. A survey of archaeological samples dated in 1984

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1985-10-01

    A survey is given of archaeological samples dated in 1984 at the Nordic Laboratory for Thermoluminescence Dating. A total of 79 samples were dated, 49 of which were burnt stones. All results were corrected for fading as measured for samples stored for four weeks at room temperature. The alpha dose contribution from uranium in the quartz and feldspar grains was included assuming an alpha efficiency facotr of 0.1 for quartz and 0.2 for feldspars. (author)

  4. Mobile Technology Use by People Experiencing Multiple Sclerosis Fatigue: Survey Methodology.

    Science.gov (United States)

    Van Kessel, Kirsten; Babbage, Duncan R; Reay, Nicholas; Miner-Williams, Warren M; Kersten, Paula

    2017-02-28

    Fatigue is one of the most commonly reported symptoms of multiple sclerosis (MS). It has a profound impact on all spheres of life, for people with MS and their relatives. It is one of the key precipitants of early retirement. Individual, group, and Internet cognitive behavioral therapy-based approaches to supporting people with MS to manage their fatigue have been shown to be effective. The aim of this project was to (1) survey the types of mobile devices and level of Internet access people with MS use or would consider using for a health intervention and (2) characterize the levels of fatigue severity and their impact experienced by the people in our sample to provide an estimate of fatigue severity of people with MS in New Zealand. The ultimate goal of this work was to support the future development of a mobile intervention for the management of fatigue for people with MS. Survey methodology using an online questionnaire was used to assess people with MS. A total of 51 people with MS participated. The average age was 48.5 years, and the large majority of the sample (77%) was female. Participants reported significant levels of fatigue as measured with the summary score of the Neurological Fatigue Index (mean 31.4 [SD 5.3]). Most (84%) respondents scored on average more than 3 on the fatigue severity questions, reflecting significant fatigue. Mobile phone usage was high with 86% of respondents reporting having a mobile phone; apps were used by 75% of respondents. Most participants (92%) accessed the Internet from home. New Zealand respondents with MS experienced high levels of both fatigue severity and fatigue impact. The majority of participants have a mobile device and access to the Internet. These findings, along with limited access to face-to-face cognitive behavioral therapy-based interventions, create an opportunity to develop a mobile technology platform for delivering a cognitive behavioral therapy-based intervention to decrease the severity and impact of

  5. Delirium diagnosis methodology used in research: a survey-based study.

    Science.gov (United States)

    Neufeld, Karin J; Nelliot, Archana; Inouye, Sharon K; Ely, E Wesley; Bienvenu, O Joseph; Lee, Hochang Benjamin; Needham, Dale M

    2014-12-01

    To describe methodology used to diagnose delirium in research studies evaluating delirium detection tools. The authors used a survey to address reference rater methodology for delirium diagnosis, including rater characteristics, sources of patient information, and diagnostic process, completed via web or telephone interview according to respondent preference. Participants were authors of 39 studies included in three recent systematic reviews of delirium detection instruments in hospitalized patients. Authors from 85% (N = 33) of the 39 eligible studies responded to the survey. The median number of raters per study was 2.5 (interquartile range: 2-3); 79% were physicians. The raters' median duration of clinical experience with delirium diagnosis was 7 years (interquartile range: 4-10), with 5% having no prior clinical experience. Inter-rater reliability was evaluated in 70% of studies. Cognitive tests and delirium detection tools were used in the delirium reference rating process in 61% (N = 21) and 45% (N = 15) of studies, respectively, with 33% (N = 11) using both and 27% (N = 9) using neither. When patients were too drowsy or declined to participate in delirium evaluation, 70% of studies (N = 23) used all available information for delirium diagnosis, whereas 15% excluded such patients. Significant variability exists in reference standard methods for delirium diagnosis in published research. Increasing standardization by documenting inter-rater reliability, using standardized cognitive and delirium detection tools, incorporating diagnostic expert consensus panels, and using all available information in patients declining or unable to participate with formal testing may help advance delirium research by increasing consistency of case detection and improving generalizability of research results. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  6. A two-phase sampling survey for nonresponse and its paradata to correct nonresponse bias in a health surveillance survey.

    Science.gov (United States)

    Santin, G; Bénézet, L; Geoffroy-Perez, B; Bouyer, J; Guéguen, A

    2017-02-01

    The decline in participation rates in surveys, including epidemiological surveillance surveys, has become a real concern since it may increase nonresponse bias. The aim of this study is to estimate the contribution of a complementary survey among a subsample of nonrespondents, and the additional contribution of paradata in correcting for nonresponse bias in an occupational health surveillance survey. In 2010, 10,000 workers were randomly selected and sent a postal questionnaire. Sociodemographic data were available for the whole sample. After data collection of the questionnaires, a complementary survey among a random subsample of 500 nonrespondents was performed using a questionnaire administered by an interviewer. Paradata were collected for the complete subsample of the complementary survey. Nonresponse bias in the initial sample and in the combined samples were assessed using variables from administrative databases available for the whole sample, not subject to differential measurement errors. Corrected prevalences by reweighting technique were estimated by first using the initial survey alone and then the initial and complementary surveys combined, under several assumptions regarding the missing data process. Results were compared by computing relative errors. The response rates of the initial and complementary surveys were 23.6% and 62.6%, respectively. For the initial and the combined surveys, the relative errors decreased after correction for nonresponse on sociodemographic variables. For the combined surveys without paradata, relative errors decreased compared with the initial survey. The contribution of the paradata was weak. When a complex descriptive survey has a low response rate, a short complementary survey among nonrespondents with a protocol which aims to maximize the response rates, is useful. The contribution of sociodemographic variables in correcting for nonresponse bias is important whereas the additional contribution of paradata in

  7. Sample Archaeological Survey of Public Use Areas, Milford Lake, Kansas

    Science.gov (United States)

    1982-09-01

    especially ceramics); Middle "" Mississippian, Middle Woodland and Central Plains archaeology ; the engineering and building technology of the Maya ...Sample Archaeological Survey of Public Use Areas -- 0C 0 awo (L" . .614 4.- -. 1?CNOV 1 40484 * , "n. O ji - 0" By Laura S. Schwiekhard Thn ’.iint haUs...RECIPIENT’S CATALOG NUMBER 4. TITLE (and Subtitle) 5. TYPE OF REPORT & PERIOD COVERED Milford Lake, Kansas Sample Archaeological Survey of Public Use

  8. Analyzing Repeated Measures Marginal Models on Sample Surveys with Resampling Methods

    Directory of Open Access Journals (Sweden)

    James D. Knoke

    2005-12-01

    Full Text Available Packaged statistical software for analyzing categorical, repeated measures marginal models on sample survey data with binary covariates does not appear to be available. Consequently, this report describes a customized SAS program which accomplishes such an analysis on survey data with jackknifed replicate weights for which the primary sampling unit information has been suppressed for respondent confidentiality. First, the program employs the Macro Language and the Output Delivery System (ODS to estimate the means and covariances of indicator variables for the response variables, taking the design into account. Then, it uses PROC CATMOD and ODS, ignoring the survey design, to obtain the design matrix and hypothesis test specifications. Finally, it enters these results into another run of CATMOD, which performs automated direct input of the survey design specifications and accomplishes the appropriate analysis. This customized SAS program can be employed, with minor editing, to analyze general categorical, repeated measures marginal models on sample surveys with replicate weights. Finally, the results of our analysis accounting for the survey design are compared to the results of two alternate analyses of the same data. This comparison confirms that such alternate analyses, which do not properly account for the design, do not produce useful results.

  9. A survey of archaeological samples dated in 1987

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1988-10-01

    A survey is given of archaeological samples dated in 1987 at the Nordic Laboratory for Thermoluminescence Dating. A total of 74 samples were dated. The results were corrected for short-term fading of feldspars as measured for samples stored at room temperature for four weeks or at 100 deg. C for two weeks. The beta dose from potassium and rubidium in feldspar, and the alpha dose from uranium and thorium in quartz and feldspar were included, assuming alpha efficiency factors of 0.1 for quartz and 0.2 for feldspar. (author) 20 tabs., 29 refs

  10. A survey of archaeological samples dated in 1985

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1986-11-01

    A survey is given of archaeological samples received for dating in 1985 at the Nordic Laboratory for Thermoluminescence Dating. A total of 66 samples were dated, 42 of which were burnt stones. All results were corrected for short- term fading as measured for samples stored at room temperature for four weeks. The beta dose from potassium and rubidium in feldspar and the alpha dose from uranium and thorium in quarts and feldspar were included assuming alpha efficiency factors of 0.1 for quartz and 0.2 for feldspar. (author)

  11. A survey of archaeological samples dated in 1986

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1987-10-01

    A survey is given of archaeological samples dated in 1986 at the Nordic Laboratory for Thermoluminescence Dating. A total of 56 samples were dated. The results were corrected for shortterm fading measured for samples stored for four weeks at room temperature or at 100 deg. C. The beta dose from potassium and rubidium in feldspar and the alpha dose from uranium and thorium in quartz and feldspar grain were included assuming alpha efficiency factors of 0.1 and 0.2 for quartz and feldspar, respectively. 21 refs. (author)

  12. Further observations on comparison of immunization coverage by lot quality assurance sampling and 30 cluster sampling.

    Science.gov (United States)

    Singh, J; Jain, D C; Sharma, R S; Verghese, T

    1996-06-01

    Lot Quality Assurance Sampling (LQAS) and standard EPI methodology (30 cluster sampling) were used to evaluate immunization coverage in a Primary Health Center (PHC) where coverage levels were reported to be more than 85%. Of 27 sub-centers (lots) evaluated by LQAS, only 2 were accepted for child coverage, whereas none was accepted for tetanus toxoid (TT) coverage in mothers. LQAS data were combined to obtain an estimate of coverage in the entire population; 41% (95% CI 36-46) infants were immunized appropriately for their ages, while 42% (95% CI 37-47) of their mothers had received a second/ booster dose of TT. TT coverage in 149 contemporary mothers sampled in EPI survey was also 42% (95% CI 31-52). Although results by the two sampling methods were consistent with each other, a big gap was evident between reported coverage (in children as well as mothers) and survey results. LQAS was found to be operationally feasible, but it cost 40% more and required 2.5 times more time than the EPI survey. LQAS therefore, is not a good substitute for current EPI methodology to evaluate immunization coverage in a large administrative area. However, LQAS has potential as method to monitor health programs on a routine basis in small population sub-units, especially in areas with high and heterogeneously distributed immunization coverage.

  13. Teachers' Attitude towards Implementation of Learner-Centered Methodology in Science Education in Kenya

    Science.gov (United States)

    Ndirangu, Caroline

    2017-01-01

    This study aims to evaluate teachers' attitude towards implementation of learner-centered methodology in science education in Kenya. The study used a survey design methodology, adopting the purposive, stratified random and simple random sampling procedures and hypothesised that there was no significant relationship between the head teachers'…

  14. Methodology for sample preparation and size measurement of commercial ZnO nanoparticles

    Directory of Open Access Journals (Sweden)

    Pei-Jia Lu

    2018-04-01

    Full Text Available This study discusses the strategies on sample preparation to acquire images with sufficient quality for size characterization by scanning electron microscope (SEM using two commercial ZnO nanoparticles of different surface properties as a demonstration. The central idea is that micrometer sized aggregates of ZnO in powdered forms need to firstly be broken down to nanosized particles through an appropriate process to generate nanoparticle dispersion before being deposited on a flat surface for SEM observation. Analytical tools such as contact angle, dynamic light scattering and zeta potential have been utilized to optimize the procedure for sample preparation and to check the quality of the results. Meanwhile, measurements of zeta potential values on flat surfaces also provide critical information and save lots of time and efforts in selection of suitable substrate for particles of different properties to be attracted and kept on the surface without further aggregation. This simple, low-cost methodology can be generally applied on size characterization of commercial ZnO nanoparticles with limited information from vendors. Keywords: Zinc oxide, Nanoparticles, Methodology

  15. Draft report: a selection methodology for LWR safety R and D programs and proposals

    International Nuclear Information System (INIS)

    Husseiny, A.A.; Ritzman, R.L.

    1980-03-01

    The results of work done to develop a methodology for selecting LWR safety R and D programs and proposals is described. A critical survey of relevant decision analysis methods is provided including the specifics of multiattribute utility theory. This latter method forms the basis of the developed selection methodology. Details of the methodology and its use are provided along with a sample illustration of its application

  16. Draft report: a selection methodology for LWR safety R and D programs and proposals

    Energy Technology Data Exchange (ETDEWEB)

    Husseiny, A. A.; Ritzman, R. L.

    1980-03-01

    The results of work done to develop a methodology for selecting LWR safety R and D programs and proposals is described. A critical survey of relevant decision analysis methods is provided including the specifics of multiattribute utility theory. This latter method forms the basis of the developed selection methodology. Details of the methodology and its use are provided along with a sample illustration of its application.

  17. Survey of Dynamic PSA Methodologies

    International Nuclear Information System (INIS)

    Lee, Hansul; Kim, Hyeonmin; Heo, Gyunyoung; Kim, Taewan

    2015-01-01

    Event Tree(ET)/Fault Tree(FT) are significant methodology in Probabilistic Safety Assessment(PSA) for Nuclear Power Plants(NPPs). ET/FT methodology has the advantage for users to be able to easily learn and model. It enables better communication between engineers engaged in the same field. However, conventional methodologies are difficult to cope with the dynamic behavior (e.g. operation mode changes or sequence-dependent failure) and integrated situation of mechanical failure and human errors. Meanwhile, new possibilities are coming for the improved PSA by virtue of the dramatic development on digital hardware, software, information technology, and data analysis.. More specifically, the computing environment has been greatly improved with being compared to the past, so we are able to conduct risk analysis with the large amount of data actually available. One method which can take the technological advantages aforementioned should be the dynamic PSA such that conventional ET/FT can have time- and condition-dependent behaviors in accident scenarios. In this paper, we investigated the various enabling techniques for the dynamic PSA. Even though its history and academic achievement was great, it seems less interesting from industrial and regulatory viewpoint. Authors expect this can contribute to better understanding of dynamic PSA in terms of algorithm, practice, and applicability. In paper, the overview for the dynamic PSA was conducted. Most of methodologies share similar concepts. Among them, DDET seems a backbone for most of methodologies since it can be applied to large problems. The common characteristics sharing the concept of DDET are as follows: • Both deterministic and stochastic approaches • Improves the identification of PSA success criteria • Helps to limit detrimental effects of sequence binning (normally adopted in PSA) • Helps to avoid defining non-optimal success criteria that may distort the risk • Framework for comprehensively considering

  18. Survey of Dynamic PSA Methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hansul; Kim, Hyeonmin; Heo, Gyunyoung [Kyung Hee University, Yongin (Korea, Republic of); Kim, Taewan [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-05-15

    Event Tree(ET)/Fault Tree(FT) are significant methodology in Probabilistic Safety Assessment(PSA) for Nuclear Power Plants(NPPs). ET/FT methodology has the advantage for users to be able to easily learn and model. It enables better communication between engineers engaged in the same field. However, conventional methodologies are difficult to cope with the dynamic behavior (e.g. operation mode changes or sequence-dependent failure) and integrated situation of mechanical failure and human errors. Meanwhile, new possibilities are coming for the improved PSA by virtue of the dramatic development on digital hardware, software, information technology, and data analysis.. More specifically, the computing environment has been greatly improved with being compared to the past, so we are able to conduct risk analysis with the large amount of data actually available. One method which can take the technological advantages aforementioned should be the dynamic PSA such that conventional ET/FT can have time- and condition-dependent behaviors in accident scenarios. In this paper, we investigated the various enabling techniques for the dynamic PSA. Even though its history and academic achievement was great, it seems less interesting from industrial and regulatory viewpoint. Authors expect this can contribute to better understanding of dynamic PSA in terms of algorithm, practice, and applicability. In paper, the overview for the dynamic PSA was conducted. Most of methodologies share similar concepts. Among them, DDET seems a backbone for most of methodologies since it can be applied to large problems. The common characteristics sharing the concept of DDET are as follows: • Both deterministic and stochastic approaches • Improves the identification of PSA success criteria • Helps to limit detrimental effects of sequence binning (normally adopted in PSA) • Helps to avoid defining non-optimal success criteria that may distort the risk • Framework for comprehensively considering

  19. A survey of archaeological samples dated in 1988

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1989-08-01

    A survey is given of archaeological samples dated in 1988 at the Nordic Laboratory for Thermoluminescence Dating. A total of 67 samples were dated. The results were corrected for short-term fading of feldspars as measured for samples stored at room temperature for four weeks or at 100 deg. C for two weeks. The beta dose from potassium and rubidium in feldspar, and the alpha dose from uranium and thorium in quartz and feldspar were included assuming alpha efficiency factors of 0.1 for quartz and 0.2 for feldspar. (author) 22 tabs., 1 ill., 14 refs

  20. Novel platform for ocean survey and autonomous sampling using multi-agent system

    OpenAIRE

    Taher, Tawfiq; Weymouth, G.D.; Varghese, Tony

    2013-01-01

    In-situ surveying and sampling of ocean environments provides critical data for laboratory work and oceanographic research. However, sampling a time-varying ocean field is often time and resource limited-meaning that samples often miss the features of interest. This paper presents a modular autonomous multi-agent robotic system which has been developed to accommodate a variety of research activities. This paper demonstrates the complementary capabilities of the agents by simultaneously survey...

  1. UAV-Borne photogrammetry: a low cost 3D surveying methodology for cartographic update

    Directory of Open Access Journals (Sweden)

    Caroti Gabriella

    2017-01-01

    Full Text Available Territorial management requires the most possible up-to-date mapping support of the status quo. Regional scale cartography update cycle is in the medium term (10 to 15 years: therefore, in the intervening time between updates relevant Authorities must provide timely updates for new works or territorial changes. Required surveys can exploit several technologies: ground-based GPS, Terrestrial Laser Scanning (TLS, traditional topography, or, in the case of wider areas, airborne photogrammetry or laser scanning. In recent years UAV-based photogrammetry is becoming increasingly widespread as a versatile, low-cost surveying system for small to medium areas. This surveying methodology was used to generate, in order, a dense point cloud, a high resolution Digital Surface Model (DSM and an orthophotograph of a newly built marina by the mouth of the Arno river in Pisa, Italy, which is not yet included in cartography. Surveying activities took place while the construction site was in operation. Case study issues surfaced in the course of the survey are presented and discussed, suggesting ‘good practice’ rules which, if followed in the survey planning step, can lessen unwanted effects due to criticalities. Besides, results of quality analysis of orthophotographs generated by UAV-borne images are also presented. Such results are discussed in view of a possible use of orthophotographs in updating medium- to large-scale cartography and checked against existing blueprints.

  2. Towards an Airframe Noise Prediction Methodology: Survey of Current Approaches

    Science.gov (United States)

    Farassat, Fereidoun; Casper, Jay H.

    2006-01-01

    In this paper, we present a critical survey of the current airframe noise (AFN) prediction methodologies. Four methodologies are recognized. These are the fully analytic method, CFD combined with the acoustic analogy, the semi-empirical method and fully numerical method. It is argued that for the immediate need of the aircraft industry, the semi-empirical method based on recent high quality acoustic database is the best available method. The method based on CFD and the Ffowcs William- Hawkings (FW-H) equation with penetrable data surface (FW-Hpds ) has advanced considerably and much experience has been gained in its use. However, more research is needed in the near future particularly in the area of turbulence simulation. The fully numerical method will take longer to reach maturity. Based on the current trends, it is predicted that this method will eventually develop into the method of choice. Both the turbulence simulation and propagation methods need to develop more for this method to become useful. Nonetheless, the authors propose that the method based on a combination of numerical and analytical techniques, e.g., CFD combined with FW-H equation, should also be worked on. In this effort, the current symbolic algebra software will allow more analytical approaches to be incorporated into AFN prediction methods.

  3. Pairing call-response surveys and distance sampling for a mammalian carnivore

    Science.gov (United States)

    Hansen, Sara J. K.; Frair, Jacqueline L.; Underwood, Harold B.; Gibbs, James P.

    2015-01-01

    Density estimates accounting for differential animal detectability are difficult to acquire for wide-ranging and elusive species such as mammalian carnivores. Pairing distance sampling with call-response surveys may provide an efficient means of tracking changes in populations of coyotes (Canis latrans), a species of particular interest in the eastern United States. Blind field trials in rural New York State indicated 119-m linear error for triangulated coyote calls, and a 1.8-km distance threshold for call detectability, which was sufficient to estimate a detection function with precision using distance sampling. We conducted statewide road-based surveys with sampling locations spaced ≥6 km apart from June to August 2010. Each detected call (be it a single or group) counted as a single object, representing 1 territorial pair, because of uncertainty in the number of vocalizing animals. From 524 survey points and 75 detections, we estimated the probability of detecting a calling coyote to be 0.17 ± 0.02 SE, yielding a detection-corrected index of 0.75 pairs/10 km2 (95% CI: 0.52–1.1, 18.5% CV) for a minimum of 8,133 pairs across rural New York State. Importantly, we consider this an index rather than true estimate of abundance given the unknown probability of coyote availability for detection during our surveys. Even so, pairing distance sampling with call-response surveys provided a novel, efficient, and noninvasive means of monitoring populations of wide-ranging and elusive, albeit reliably vocal, mammalian carnivores. Our approach offers an effective new means of tracking species like coyotes, one that is readily extendable to other species and geographic extents, provided key assumptions of distance sampling are met.

  4. Objectives and methodology of Romanian SEPHAR II Survey. Project for comparing the prevalence and control of cardiovascular risk factors in two East-European countries: Romania and Poland.

    Science.gov (United States)

    Dorobantu, Maria; Tautu, Oana-Florentina; Darabont, Roxana; Ghiorghe, Silviu; Badila, Elisabeta; Dana, Minca; Dobreanu, Minodora; Baila, Ilarie; Rutkowski, Marcin; Zdrojewski, Tomasz

    2015-08-12

    Comparing results of representative surveys conducted in different East-European countries could contribute to a better understanding and management of cardiovascular risk factors, offering grounds for the development of health policies addressing the special needs of this high cardiovascular risk region of Europe. The aim of this paper was to describe the methodology on which the comparison between the Romanian survey SEPHAR II and the Polish survey NATPOL 2011 results is based. SEPHAR II, like NATPOL 2011, is a cross-sectional survey conducted on a representative sample of the adult Romanian population (18 to 80 years) and encompasses two visits with the following components: completing the study questionnaire, blood pressure and anthropometric measurements, and collection of blood and urine samples. From a total of 2223 subjects found at 2860 visited addresses, 2044 subjects gave written consent but only 1975 subjects had eligible data for the analysis, accounting for a response rate of 69.06%. Additionally we excluded 11 subjects who were 80 years of age (NATPOL 2011 included adult subjects up to 79 years). Therefore, the sample size included in the statistical analysis is 1964. It has similar age groups and gender structure as the Romanian population aged 18-79 years from the last census available at the moment of conducting the survey (weight adjustments for epidemiological analyses range from 0.48 to 8.7). Sharing many similarities, the results of SEPHAR II and NATPOL 2011 surveys can be compared by a proper statistical method offering crucial information regarding cardiovascular risk factors in a high-cardiovascular risk European region.

  5. A two-stage cluster sampling method using gridded population data, a GIS, and Google EarthTM imagery in a population-based mortality survey in Iraq

    Directory of Open Access Journals (Sweden)

    Galway LP

    2012-04-01

    Full Text Available Abstract Background Mortality estimates can measure and monitor the impacts of conflict on a population, guide humanitarian efforts, and help to better understand the public health impacts of conflict. Vital statistics registration and surveillance systems are rarely functional in conflict settings, posing a challenge of estimating mortality using retrospective population-based surveys. Results We present a two-stage cluster sampling method for application in population-based mortality surveys. The sampling method utilizes gridded population data and a geographic information system (GIS to select clusters in the first sampling stage and Google Earth TM imagery and sampling grids to select households in the second sampling stage. The sampling method is implemented in a household mortality study in Iraq in 2011. Factors affecting feasibility and methodological quality are described. Conclusion Sampling is a challenge in retrospective population-based mortality studies and alternatives that improve on the conventional approaches are needed. The sampling strategy presented here was designed to generate a representative sample of the Iraqi population while reducing the potential for bias and considering the context specific challenges of the study setting. This sampling strategy, or variations on it, are adaptable and should be considered and tested in other conflict settings.

  6. An EPRI methodology for determining and monitoring simulator operating limits

    International Nuclear Information System (INIS)

    Eichelberg, R.; Pellechi, M.; Wolf, B.; Colley, R.

    1989-01-01

    Of paramount concern to nuclear utilities today is whether their plant-referenced simulator(s) comply with ANSI/ANS 3.5-1985. Of special interest is Section 4.3 of the Standard which requires, in part, that a means be provided to alert the instructor when certain parameters approach values indicative of events beyond the implemented model or known plant behavior. EPRI established Research Project 2054-2 to develop a comprehensive plan for determining, monitoring, and implementing simulator operating limits. As part of the project, a survey was conducted to identify the current/anticipated approach each of the sampled utilities was using to meet the requirements of Section 4.3. A preliminary methodology was drafted and host utilities interviewed. The interview process led to redefining the methodology. This paper covers the objectives of the EPRI project, survey responses, overview of the methodology, resource requirements and conclusions

  7. On the problems of PPS sampling in multi-character surveys ...

    African Journals Online (AJOL)

    This paper, which is on the problems of PPS sampling in multi-character surveys, compares the efficiency of some estimators used in PPSWR sampling for multiple characteristics. From a superpopulation model, we computed the expected variances of the different estimators for each of the first two finite populations ...

  8. Experience-Sampling Methodology with a Mobile Device in Fibromyalgia

    Directory of Open Access Journals (Sweden)

    Castilla Diana

    2012-01-01

    Full Text Available This work describes the usability studies conducted in the development of an experience-sampling methodology (ESM system running in a mobile device. The goal of the system is to improve the accuracy and ecology in gathering daily self-report data in individuals suffering a chronic pain condition, fibromyalgia. The usability studies showed that the developed software to conduct ESM with mobile devices (smartphones, cell phones can be successfully used by individuals with fibromyalgia of different ages and with low level of expertise in the use of information and communication technologies. 100% of users completed the tasks successfully, although some have completely illiterate. Also there seems to be a clear difference in the way of interaction obtained in the two studies carried out.

  9. Measuring medicine prices in Peru: validation of key aspects of WHO/HAI survey methodology.

    Science.gov (United States)

    Madden, Jeanne M; Meza, Edson; Ewen, Margaret; Laing, Richard O; Stephens, Peter; Ross-Degnan, Dennis

    2010-04-01

    To assess the possibility of bias due to the limited target list and geographic sampling of the World Health Organization (WHO)/Health Action International (HAI) Medicine Prices and Availability survey used in more than 70 rapid sample surveys since 2001. A survey was conducted in Peru in 2005 using an expanded sample of medicine outlets, including remote areas. Comprehensive data were gathered on medicines in three therapeutic classes to assess the adequacy of WHO/HAI's target medicines list and the focus on only two product versions. WHO/HAI median retail prices were compared with average wholesale prices from global pharmaceutical sales data supplier IMS Health. No significant differences were found in overall availability or prices of target list medicines by retail location. The comprehensive survey of angiotensin-converting enzyme inhibitor, anti-diabetic, and anti-ulcer products revealed that some treatments not on the target list were costlier for patients and more likely to be unavailable, particularly in remote areas. WHO/HAI retail prices and IMS wholesale prices were strongly correlated for higher priced products, and weakly correlated for lower priced products (which had higher estimated retailer markups). The WHO/HAI survey approach strikes an appropriate balance between modest research costs and optimal information for policy. Focusing on commonly used medicines yields sufficient and valid results. Surveyors elsewhere should consider the limits of the survey data as well as any local circumstances, such as scarcity, that may call for extra field efforts.

  10. Sample size methods for estimating HIV incidence from cross-sectional surveys.

    Science.gov (United States)

    Konikoff, Jacob; Brookmeyer, Ron

    2015-12-01

    Understanding HIV incidence, the rate at which new infections occur in populations, is critical for tracking and surveillance of the epidemic. In this article, we derive methods for determining sample sizes for cross-sectional surveys to estimate incidence with sufficient precision. We further show how to specify sample sizes for two successive cross-sectional surveys to detect changes in incidence with adequate power. In these surveys biomarkers such as CD4 cell count, viral load, and recently developed serological assays are used to determine which individuals are in an early disease stage of infection. The total number of individuals in this stage, divided by the number of people who are uninfected, is used to approximate the incidence rate. Our methods account for uncertainty in the durations of time spent in the biomarker defined early disease stage. We find that failure to account for this uncertainty when designing surveys can lead to imprecise estimates of incidence and underpowered studies. We evaluated our sample size methods in simulations and found that they performed well in a variety of underlying epidemics. Code for implementing our methods in R is available with this article at the Biometrics website on Wiley Online Library. © 2015, The International Biometric Society.

  11. Concrete crushing and sampling, a methodology and technology for the unconditional release of concrete material from decommissioning

    International Nuclear Information System (INIS)

    Baumann, S.; Teunckens, L.; Walthery, R.; Lewandowski, P.; Millen, D.

    2002-01-01

    Belgoprocess started the industrial decommissioning of the main process building of the former Eurochemic reprocessing plant in 1990, after completion of a pilot project. Two small storage buildings for final products from reprocessing were dismantled to verify the assumptions made in a previous paper study on decommissioning, to demonstrate and develop dismantling techniques and to train personnel. Both buildings were emptied and decontaminated to background levels. They were demolished and the remaining concrete debris was disposed of as industrial waste and green field conditions restored. Currently, the decommissioning operations carried out at the main building have made substantial progress. They are executed on an industrial scale and will continue till the end of 2005. In view of the final demolition of the building, a clearance methodology has to be proposed. Application of the methodology applied for the storage buildings of the pilot project is complicated for several reasons. Although this methodology is not rejected as such, an alternative has been studied thoroughly. It considers at least one complete measurement of all concrete structures and the removal of all detected residual radioactivity. This monitoring sequence is followed by a controlled demolition of the concrete structures and crushing of the resulting concrete parts to smaller particles. During the crushing operations, metal parts are separated from the concrete and representative concrete samples are taken. The frequency of sampling meets the prevailing standards. In a further step, the concrete samples are milled, homogenised, and a smaller fraction is sent to the laboratory for analyses. The paper describes the developed concrete crushing and sampling methodology. (authors)

  12. Adaptive Intervention Methodology for Reduction of Respondent Contact Burden in the American Community Survey

    Directory of Open Access Journals (Sweden)

    Ashmead Robert

    2017-12-01

    Full Text Available The notion of respondent contact burden in sample surveys is defined, and a multi-stage process to develop policies for curtailing nonresponse follow-up is described with the goal of reducing this burden on prospective survey respondents. The method depends on contact history paradata containing information about contact attempts both for respondents and for sampled nonrespondents. By analysis of past data, policies to stop case follow-up based on control variables measured in paradata can be developed by calculating propensities to respond for paradata-defined subgroups of sampled cases. Competing policies can be assessed by comparing outcomes (lost interviews, numbers of contacts, patterns of reluctant participation, or refusal to participate as if these stopping policies had been followed in past data. Finally, embedded survey experiments may be used to assess contact-burden reduction policies when these are implemented in the field. The multi-stage method described here abstracts the stages followed in a series of research studies aimed at reducing contact burden in the Computer Assisted Telephone Interview (CATI and Computer Assisted Personal Interview (CAPI modes of the American Community Survey (ACS, which culminated in implementation of policy changes in the ACS.

  13. An End-to-End DNA Taxonomy Methodology for Benthic Biodiversity Survey in the Clarion-Clipperton Zone, Central Pacific Abyss

    Directory of Open Access Journals (Sweden)

    Adrian G. Glover

    2015-12-01

    Full Text Available Recent years have seen increased survey and sampling expeditions to the Clarion-Clipperton Zone (CCZ, central Pacific Ocean abyss, driven by commercial interests from contractors in the potential extraction of polymetallic nodules in the region. Part of the International Seabed Authority (ISA regulatory requirements are that these contractors undertake environmental research expeditions to their CCZ exploration claims following guidelines approved by the ISA Legal and Technical Commission (ISA, 2010. Section 9 (e of these guidelines instructs contractors to “…collect data on the sea floor communities specifically relating to megafauna, macrofauna, meiofauna, microfauna, nodule fauna and demersal scavengers”. There are a number of methodological challenges to this, including the water depth (4000–5000 m, extremely warm surface waters (~28 °C compared to bottom water (~1.5 °C and great distances to ports requiring a large and long seagoing expedition with only a limited number of scientists. Both scientists and regulators have recently realized that a major gap in our knowledge of the region is the fundamental taxonomy of the animals that live there; this is essential to inform our knowledge of the biogeography, natural history and ultimately our stewardship of the region. Recognising this, the ISA is currently sponsoring a series of taxonomic workshops on the CCZ fauna and to assist in this process we present here a series of methodological pipelines for DNA taxonomy (incorporating both molecular and morphological data of the macrofauna and megafauna from the CCZ benthic habitat in the recent ABYSSLINE cruise program to the UK-1 exploration claim. A major problem on recent CCZ cruises has been the collection of high-quality samples suitable for both morphology and DNA taxonomy, coupled with a workflow that ensures these data are made available. The DNA sequencing techniques themselves are relatively standard, once good samples have been

  14. Who sends the email? Using electronic surveys in violence research.

    Science.gov (United States)

    Sutherland, Melissa A; Amar, Angela F; Laughon, Kathryn

    2013-08-01

    Students aged 16-24 years are at greatest risk for interpersonal violence and the resulting short and long-term health consequences. Electronic survey methodology is well suited for research related to interpersonal violence. Yet methodological questions remain about best practices in using electronic surveys. While researchers often indicate that potential participants receive multiple emails as reminders to complete the survey, little mention is made of the sender of the recruitment email. The purpose of this analysis is to describe the response rates from three violence-focused research studies when the recruitment emails are sent from a campus office, researcher or survey sampling firm. Three violence-focused studies were conducted about interpersonal violence among college students in the United States. Seven universities and a survey sampling firm were used to recruit potential participants to complete an electronic survey. The sender of the recruitment emails varied within and across the each of the studies depending on institutional review boards and university protocols. An overall response rate of 30% was noted for the 3 studies. Universities in which researcher-initiated recruitment emails were used had higher response rates compared to universities where campus officials sent the recruitment emails. Researchers found lower response rates to electronic surveys at Historically Black Colleges or Universities and that other methods were needed to improve response rates. The sender of recruitment emails for electronic surveys may be an important factor in response rates for violence-focused research. For researchers identification of best practices for survey methodology is needed to promote accurate disclosure and increase response rates.

  15. Alcohol- and Drug-Involved Driving in the United States: Methodology for the 2007 National Roadside Survey

    Science.gov (United States)

    Lacey, John H.; Kelley-Baker, Tara; Voas, Robert B.; Romano, Eduardo; Furr-Holden, C. Debra; Torres, Pedro; Berning, Amy

    2011-01-01

    This article describes the methodology used in the 2007 U.S. National Roadside Survey to estimate the prevalence of alcohol- and drug-impaired driving and alcohol- and drug-involved driving. This study involved randomly stopping drivers at 300 locations across the 48 continental U.S. states at sites selected through a stratified random sampling…

  16. The EuroPrevall-INCO surveys on the prevalence of food allergies in children from China, India and Russia: the study methodology.

    Science.gov (United States)

    Wong, G W K; Mahesh, P A; Ogorodova, L; Leung, T F; Fedorova, O; Holla, A D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; van Ree, R; Yazdanbakhsh, M; Burney, P

    2010-03-01

    Very little is known regarding the global variations in the prevalence of food allergies. The EuroPrevall-INCO project has been developed to evaluate the prevalence of food allergies in China, India and Russia using the standardized methodology of the EuroPrevall protocol used for studies in the European Union. The epidemiological surveys of the project were designed to estimate variations in the prevalence of food allergy and exposure to known or suspected risk factors for food allergy and to compare the data with different European countries. Random samples of primary schoolchildren were recruited from urban and rural regions of China, Russia and India for screening to ascertain possible adverse reactions to foods. Cases and controls were then selected to answer a detailed questionnaire designed to evaluate the possible risk factors of food allergies. Objective evidence of sensitisation including skin-prick test and serum specific IgE measurement was also collected. More than 37 000 children from the three participating countries have been screened. The response rates for the screening phase ranged from 83% to 95%. More than 3000 cases and controls were studied in the second phase of the study. Further confirmation of food allergies by double blind food challenge was conducted. This will be the first comparative study of the epidemiology of food allergies in China, India, and Russia using the same standardized methodology. The findings of these surveys will complement the data obtained from Europe and provide insights into the development of food allergy.

  17. The prevalence of workaholism: a survey study in a nationally representative sample of Norwegian employees.

    Directory of Open Access Journals (Sweden)

    Cecilie Schou Andreassen

    Full Text Available Workaholism has become an increasingly popular area for empirical study. However, most studies examining the prevalence of workaholism have used non-representative samples and measures with poorly defined cut-off scores. To overcome these methodological limitations, a nationally representative survey among employees in Norway (N = 1,124 was conducted. Questions relating to gender, age, marital status, caretaker responsibility for children, percentage of full-time equivalent, and educational level were asked. Workaholism was assessed by the use of a psychometrically validated instrument (i.e., Bergen Work Addiction Scale. Personality was assessed using the Mini-International Personality Item Pool. Results showed that the prevalence of workaholism was 8.3% (95% CI  = 6.7-9.9%. An adjusted logistic regression analysis showed that workaholism was negatively related to age and positively related to the personality dimensions agreeableness, neuroticism, and intellect/imagination. Implications for these findings are discussed.

  18. Methodological issues affecting the study of fish parasites. II. Sampling method affects ectoparasite studies

    Czech Academy of Sciences Publication Activity Database

    Kvach, Yuriy; Ondračková, Markéta; Janáč, Michal; Jurajda, Pavel

    2016-01-01

    Roč. 121, č. 1 (2016), s. 59-66 ISSN 0177-5103 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Parasite community * Fish sampling method * Methodology * Parasitological examination * Rutilus rutilus Subject RIV: EG - Zoology Impact factor: 1.549, year: 2016

  19. Semi-automatic surface sediment sampling system - A prototype to be implemented in bivalve fishing surveys

    Science.gov (United States)

    Rufino, Marta M.; Baptista, Paulo; Pereira, Fábio; Gaspar, Miguel B.

    2018-01-01

    In the current work we propose a new method to sample surface sediment during bivalve fishing surveys. Fishing institutes all around the word carry out regular surveys with the aim of monitoring the stocks of commercial species. These surveys comprise often more than one hundred of sampling stations and cover large geographical areas. Although superficial sediment grain sizes are among the main drivers of benthic communities and provide crucial information for studies on coastal dynamics, overall there is a strong lack of this type of data, possibly, because traditional surface sediment sampling methods use grabs, that require considerable time and effort to be carried out on regular basis or on large areas. In face of these aspects, we developed an easy and un-expensive method to sample superficial sediments, during bivalve fisheries monitoring surveys, without increasing survey time or human resources. The method was successfully evaluated and validated during a typical bivalve survey carried out on the Northwest coast of Portugal, confirming that it had any interference with the survey objectives. Furthermore, the method was validated by collecting samples using a traditional Van Veen grabs (traditional method), which showed a similar grain size composition to the ones collected by the new method, on the same localities. We recommend that the procedure is implemented on regular bivalve fishing surveys, together with an image analysis system to analyse the collected samples. The new method will provide substantial quantity of data on surface sediment in coastal areas, using a non-expensive and efficient manner, with a high potential application in different fields of research.

  20. To give or not to give, that's the question: How methodology is destiny in Dutch giving data

    NARCIS (Netherlands)

    Bekkers, R.H.F.P.; Wiepking, P.

    2006-01-01

    In research on giving, methodology is destiny. The volume of donations estimated from sample surveys strongly depends on the length of the questionnaire used to measure giving. By comparing two giving surveys from the Netherlands, the authors show that a short questionnaire on giving not only

  1. Sampling guidelines for oral fluid-based surveys of group-housed animals.

    Science.gov (United States)

    Rotolo, Marisa L; Sun, Yaxuan; Wang, Chong; Giménez-Lirola, Luis; Baum, David H; Gauger, Phillip C; Harmon, Karen M; Hoogland, Marlin; Main, Rodger; Zimmerman, Jeffrey J

    2017-09-01

    Formulas and software for calculating sample size for surveys based on individual animal samples are readily available. However, sample size formulas are not available for oral fluids and other aggregate samples that are increasingly used in production settings. Therefore, the objective of this study was to develop sampling guidelines for oral fluid-based porcine reproductive and respiratory syndrome virus (PRRSV) surveys in commercial swine farms. Oral fluid samples were collected in 9 weekly samplings from all pens in 3 barns on one production site beginning shortly after placement of weaned pigs. Samples (n=972) were tested by real-time reverse-transcription PCR (RT-rtPCR) and the binary results analyzed using a piecewise exponential survival model for interval-censored, time-to-event data with misclassification. Thereafter, simulation studies were used to study the barn-level probability of PRRSV detection as a function of sample size, sample allocation (simple random sampling vs fixed spatial sampling), assay diagnostic sensitivity and specificity, and pen-level prevalence. These studies provided estimates of the probability of detection by sample size and within-barn prevalence. Detection using fixed spatial sampling was as good as, or better than, simple random sampling. Sampling multiple barns on a site increased the probability of detection with the number of barns sampled. These results are relevant to PRRSV control or elimination projects at the herd, regional, or national levels, but the results are also broadly applicable to contagious pathogens of swine for which oral fluid tests of equivalent performance are available. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Methodological effects in Fourier transform infrared (FTIR) spectroscopy: Implications for structural analyses of biomacromolecular samples

    Science.gov (United States)

    Kamnev, Alexander A.; Tugarova, Anna V.; Dyatlova, Yulia A.; Tarantilis, Petros A.; Grigoryeva, Olga P.; Fainleib, Alexander M.; De Luca, Stefania

    2018-03-01

    A set of experimental data obtained by Fourier transform infrared (FTIR) spectroscopy (involving the use of samples ground and pressed with KBr, i.e. in a polar halide matrix) and by matrix-free transmission FTIR or diffuse reflectance infrared Fourier transform (DRIFT) spectroscopic methodologies (involving measurements of thin films or pure powdered samples, respectively) were compared for several different biomacromolecular substances. The samples under study included poly-3-hydroxybutyrate (PHB) isolated from cell biomass of the rhizobacterium Azospirillum brasilense; dry PHB-containing A. brasilense biomass; pectin (natural carboxylated heteropolysaccharide of plant origin; obtained from apple peel) as well as its chemically modified derivatives obtained by partial esterification of its galacturonide-chain hydroxyl moieties with palmitic, oleic and linoleic acids. Significant shifts of some FTIR vibrational bands related to polar functional groups of all the biomacromolecules under study, induced by the halide matrix used for preparing the samples for spectroscopic measurements, were shown and discussed. A polar halide matrix used for preparing samples for FTIR measurements was shown to be likely to affect band positions not only per se, by affecting band energies or via ion exchange (e.g., with carboxylate moieties), but also by inducing crystallisation of metastable amorphous biopolymers (e.g., PHB of microbial origin). The results obtained have important implications for correct structural analyses of polar, H-bonded and/or amphiphilic biomacromolecular systems using different methodologies of FTIR spectroscopy.

  3. Samples and data accessibility in research biobanks: an explorative survey

    Directory of Open Access Journals (Sweden)

    Marco Capocasa

    2016-02-01

    Full Text Available Biobanks, which contain human biological samples and/or data, provide a crucial contribution to the progress of biomedical research. However, the effective and efficient use of biobank resources depends on their accessibility. In fact, making bio-resources promptly accessible to everybody may increase the benefits for society. Furthermore, optimizing their use and ensuring their quality will promote scientific creativity and, in general, contribute to the progress of bio-medical research. Although this has become a rather common belief, several laboratories are still secretive and continue to withhold samples and data. In this study, we conducted a questionnaire-based survey in order to investigate sample and data accessibility in research biobanks operating all over the world. The survey involved a total of 46 biobanks. Most of them gave permission to access their samples (95.7% and data (85.4%, but free and unconditioned accessibility seemed not to be common practice. The analysis of the guidelines regarding the accessibility to resources of the biobanks that responded to the survey highlights three issues: (i the request for applicants to explain what they would like to do with the resources requested; (ii the role of funding, public or private, in the establishment of fruitful collaborations between biobanks and research labs; (iii the request of co-authorship in order to give access to their data. These results suggest that economic and academic aspects are involved in determining the extent of sample and data sharing stored in biobanks. As a second step of this study, we investigated the reasons behind the high diversity of requirements to access biobank resources. The analysis of informative answers suggested that the different modalities of resource accessibility seem to be largely influenced by both social context and legislation of the countries where the biobanks operate.

  4. Trends in analytical methodologies for the determination of alkylphenols and bisphenol A in water samples.

    Science.gov (United States)

    Salgueiro-González, N; Muniategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D

    2017-04-15

    In the last decade, the impact of alkylphenols and bisphenol A in the aquatic environment has been widely evaluated because of their high use in industrial and household applications as well as their toxicological effects. These compounds are well-known endocrine disrupting compounds (EDCs) which can affect the hormonal system of humans and wildlife, even at low concentrations. Due to the fact that these pollutants enter into the environment through waters, and it is the most affected compartment, analytical methods which allow the determination of these compounds in aqueous samples at low levels are mandatory. In this review, an overview of the most significant advances in the analytical methodologies for the determination of alkylphenols and bisphenol A in waters is considered (from 2002 to the present). Sample handling and instrumental detection strategies are critically discussed, including analytical parameters related to quality assurance and quality control (QA/QC). Special attention is paid to miniaturized sample preparation methodologies and approaches proposed to reduce time- and reagents consumption according to Green Chemistry principles, which have increased in the last five years. Finally, relevant applications of these methods to the analysis of water samples are examined, being wastewater and surface water the most investigated. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Modern survey sampling

    CERN Document Server

    Chaudhuri, Arijit

    2014-01-01

    Exposure to SamplingAbstract Introduction Concepts of Population, Sample, and SamplingInitial RamificationsAbstract Introduction Sampling Design, Sampling SchemeRandom Numbers and Their Uses in Simple RandomSampling (SRS)Drawing Simple Random Samples with and withoutReplacementEstimation of Mean, Total, Ratio of Totals/Means:Variance and Variance EstimationDetermination of Sample SizesA.2 Appendix to Chapter 2 A.More on Equal Probability Sampling A.Horvitz-Thompson EstimatorA.SufficiencyA.LikelihoodA.Non-Existence Theorem More Intricacies Abstract Introduction Unequal Probability Sampling StrategiesPPS Sampling Exploring Improved WaysAbstract Introduction Stratified Sampling Cluster SamplingMulti-Stage SamplingMulti-Phase Sampling: Ratio and RegressionEstimationviiviii ContentsControlled SamplingModeling Introduction Super-Population ModelingPrediction Approach Model-Assisted Approach Bayesian Methods Spatial SmoothingSampling on Successive Occasions: Panel Rotation Non-Response and Not-at-Homes Weighting Adj...

  6. Who Sends the Email? Using Electronic Surveys in Violence Research

    Directory of Open Access Journals (Sweden)

    Melissa A Sutherland

    2013-08-01

    Full Text Available Introduction: Students aged 16–24 years are at greatest risk for interpersonal violence and the resulting short and long-term health consequences. Electronic survey methodology is well suited for research related to interpersonal violence. Yet methodological questions remain about best practices in using electronic surveys. While researchers often indicate that potential participants receive multiple emails as reminders to complete the survey, little mention is made of the sender of the recruitment email. The purpose of this analysis is to describe the response rates from three violence-focused research studies when the recruitment emails are sent from a campus office, researcher or survey sampling firm. Methods: Three violence-focused studies were conducted about interpersonal violence among college students in the United States. Seven universities and a survey sampling firm were used to recruit potential participants to complete an electronic survey. The sender of the recruitment emails varied within and across the each of the studies depending on institutional review boards and university protocols.Results: An overall response rate of 30% was noted for the 3 studies. Universities in which researcher initiated recruitment emails were used had higher response rates compared to universities where campus officials sent the recruitment emails. Researchers found lower response rates to electronic surveys at Historically Black Colleges or Universities and that other methods were needed to improve response rates.Conclusion: The sender of recruitment emails for electronic surveys may be an important factor in response rates for violence-focused research. For researchers identification of best practices for survey methodology is needed to promote accurate disclosure and increase response rates. [West J Emerg Med. 2013;14(4:363–369.

  7. Evaluating the quality of sampling frames used in European cross-national surveys

    NARCIS (Netherlands)

    Maineri, A.M.; Scherpenzeel, A.; Bristle, Johanna; Pflüger, Senta-Melissa; Butt, Sarah; Zins, Stefan; Emery, Tom; Luijkx, R.

    This report addresses the quality of the population registers which are currently being used as sampling frames in countries participating in the four cross-European surveys cooperating in SERISS: the European Social Survey (ESS), the European Values Study (EVS), the Gender and Generations Program

  8. To Give or Not to Give, That Is the Question : How Methodology Is Destiny in Dutch Giving Data

    NARCIS (Netherlands)

    Bekkers, René; Wiepking, Pamala

    2006-01-01

    In research on giving, methodology is destiny. The volume of donations estimated from sample surveys strongly depends on the length of the questionnaire used to measure giving. By comparing two giving surveys from the Netherlands, the authors show that a short questionnaire on giving not only

  9. Using a statewide survey methodology to prioritize pediatric cardiology core content.

    Science.gov (United States)

    Neal, Ashley E; Lehto, Elizabeth; Miller, Karen Hughes; Ziegler, Craig; Davis, Erin

    2018-01-01

    Although pediatrician-reported relevance of Canadian cardiology-specific objectives has been studied, similar data are not available for the 2016 American Board of Pediatrics (ABP) cardiology-specific objectives. This study asked Kentucky trainees, pediatricians, and pediatric cardiologists to identify "most important" content within these objectives. This cross-sectional study used an original, online survey instrument based on the 2016 ABP cardiology-specific objectives. We collected quantitative data (numerical indications of importance) and qualitative data (open-ended replies regarding missing content and difficulty in teaching and learning). Respondents indicated the top two choices of most important items within eight content areas. Descriptive statistics (frequencies and percentages) and chi-square analysis were calculated. Content within categories was organized using naturally occurring "clusters" and "gaps" in scores. Common themes among open-ended qualitative responses were identified using Pandit's version of Glaser and Strauss Grounded theory (constant comparison). Of the 136 respondents, 23 (17%) were residents, 15 (11%) fellows, 85 (62%) pediatricians, and 13 (10%) pediatric cardiologists. Of attendings, 80% reported faculty/gratis faculty status. Naturally occurring clusters in respondent-designated importance resulted in ≤3 "most selected" objectives per content area. Objectives in "most selected" content pertained to initial diagnosis (recognition of abnormality/disease) (n = 16), possible emergent/urgent intervention required (n = 14), building a differential (n = 8), and planning a workup (n = 4). Conversely, themes for "least selected" content included comanagement with subspecialist (n = 15), knowledge useful in patient-family communication (n = 9), knowledge that can be referenced (as needed) (n = 7), and longitudinal/follow-up concerns (n = 5). This study demonstrated the utility of an online survey

  10. [Comparison study on sampling methods of Oncomelania hupensis snail survey in marshland schistosomiasis epidemic areas in China].

    Science.gov (United States)

    An, Zhao; Wen-Xin, Zhang; Zhong, Yao; Yu-Kuan, Ma; Qing, Liu; Hou-Lang, Duan; Yi-di, Shang

    2016-06-29

    To optimize and simplify the survey method of Oncomelania hupensis snail in marshland endemic region of schistosomiasis and increase the precision, efficiency and economy of the snail survey. A quadrate experimental field was selected as the subject of 50 m×50 m size in Chayegang marshland near Henghu farm in the Poyang Lake region and a whole-covered method was adopted to survey the snails. The simple random sampling, systematic sampling and stratified random sampling methods were applied to calculate the minimum sample size, relative sampling error and absolute sampling error. The minimum sample sizes of the simple random sampling, systematic sampling and stratified random sampling methods were 300, 300 and 225, respectively. The relative sampling errors of three methods were all less than 15%. The absolute sampling errors were 0.221 7, 0.302 4 and 0.047 8, respectively. The spatial stratified sampling with altitude as the stratum variable is an efficient approach of lower cost and higher precision for the snail survey.

  11. Can citizen science produce good science? Testing the OPAL Air Survey methodology, using lichens as indicators of nitrogenous pollution

    International Nuclear Information System (INIS)

    Tregidgo, Daniel J.; West, Sarah E.; Ashmore, Mike R.

    2013-01-01

    Citizen science is having increasing influence on environmental monitoring as its advantages are becoming recognised. However methodologies are often simplified to make them accessible to citizen scientists. We tested whether a recent citizen science survey (the OPAL Air Survey) could detect trends in lichen community composition over transects away from roads. We hypothesised that the abundance of nitrophilic lichens would decrease with distance from the road, while that of nitrophobic lichens would increase. The hypothesised changes were detected along strong pollution gradients, but not where the road source was relatively weak, or background pollution relatively high. We conclude that the simplified OPAL methodology can detect large contrasts in nitrogenous pollution, but it may not be able to detect more subtle changes in pollution exposure. Similar studies are needed in conjunction with the ever-growing body of citizen science work to ensure that the limitations of these methods are fully understood. -- Highlights: •We investigated the validity of a simplified citizen science methodology. •Lichen abundance data were used to indicate nitrogenous air pollution. •Significant changes were detected beside busy roads with low background pollution. •The methodology detected major, but not subtle, contrasts in pollution. •Sensitivity of citizen science methods to environmental change must be evaluated. -- A simplified lichen biomonitoring method used for citizen science can detect the impact of nitrogenous air pollution from local roads

  12. Probability Sampling Method for a Hidden Population Using Respondent-Driven Sampling: Simulation for Cancer Survivors.

    Science.gov (United States)

    Jung, Minsoo

    2015-01-01

    When there is no sampling frame within a certain group or the group is concerned that making its population public would bring social stigma, we say the population is hidden. It is difficult to approach this kind of population survey-methodologically because the response rate is low and its members are not quite honest with their responses when probability sampling is used. The only alternative known to address the problems caused by previous methods such as snowball sampling is respondent-driven sampling (RDS), which was developed by Heckathorn and his colleagues. RDS is based on a Markov chain, and uses the social network information of the respondent. This characteristic allows for probability sampling when we survey a hidden population. We verified through computer simulation whether RDS can be used on a hidden population of cancer survivors. According to the simulation results of this thesis, the chain-referral sampling of RDS tends to minimize as the sample gets bigger, and it becomes stabilized as the wave progresses. Therefore, it shows that the final sample information can be completely independent from the initial seeds if a certain level of sample size is secured even if the initial seeds were selected through convenient sampling. Thus, RDS can be considered as an alternative which can improve upon both key informant sampling and ethnographic surveys, and it needs to be utilized for various cases domestically as well.

  13. Does self-selection affect samples' representativeness in online surveys? An investigation in online video game research.

    Science.gov (United States)

    Khazaal, Yasser; van Singer, Mathias; Chatton, Anne; Achab, Sophia; Zullino, Daniele; Rothen, Stephane; Khan, Riaz; Billieux, Joel; Thorens, Gabriel

    2014-07-07

    The number of medical studies performed through online surveys has increased dramatically in recent years. Despite their numerous advantages (eg, sample size, facilitated access to individuals presenting stigmatizing issues), selection bias may exist in online surveys. However, evidence on the representativeness of self-selected samples in online studies is patchy. Our objective was to explore the representativeness of a self-selected sample of online gamers using online players' virtual characters (avatars). All avatars belonged to individuals playing World of Warcraft (WoW), currently the most widely used online game. Avatars' characteristics were defined using various games' scores, reported on the WoW's official website, and two self-selected samples from previous studies were compared with a randomly selected sample of avatars. We used scores linked to 1240 avatars (762 from the self-selected samples and 478 from the random sample). The two self-selected samples of avatars had higher scores on most of the assessed variables (except for guild membership and exploration). Furthermore, some guilds were overrepresented in the self-selected samples. Our results suggest that more proficient players or players more involved in the game may be more likely to participate in online surveys. Caution is needed in the interpretation of studies based on online surveys that used a self-selection recruitment procedure. Epidemiological evidence on the reduced representativeness of sample of online surveys is warranted.

  14. USING SURVEY OF SERIES IN AUDIT

    Directory of Open Access Journals (Sweden)

    OFILEANU DIMI

    2014-12-01

    Full Text Available The efficiency of financial audit within an entity can be made by applying sampling statistical techniques. International auditing standards offer the possibility to test only part of financial information of an entity by means of different sampling techniques. The article is a rhetorical and practical speculation regarding the methodology and the possibility to apply a statistical survey of series in the research of documents and accounting records.

  15. Sampling strategy for a large scale indoor radiation survey - a pilot project

    International Nuclear Information System (INIS)

    Strand, T.; Stranden, E.

    1986-01-01

    Optimisation of a stratified random sampling strategy for large scale indoor radiation surveys is discussed. It is based on the results from a small scale pilot project where variances in dose rates within different categories of houses were assessed. By selecting a predetermined precision level for the mean dose rate in a given region, the number of measurements needed can be optimised. The results of a pilot project in Norway are presented together with the development of the final sampling strategy for a planned large scale survey. (author)

  16. Mode Equivalence of Health Indicators Between Data Collection Modes and Mixed-Mode Survey Designs in Population-Based Health Interview Surveys for Children and Adolescents: Methodological Study

    Science.gov (United States)

    Hoffmann, Robert; Houben, Robin; Krause, Laura; Kamtsiuris, Panagiotis; Gößwald, Antje

    2018-01-01

    Background The implementation of an Internet option in an existing public health interview survey using a mixed-mode design is attractive because of lower costs and faster data availability. Additionally, mixed-mode surveys can increase response rates and improve sample composition. However, mixed-mode designs can increase the risk of measurement error (mode effects). Objective This study aimed to determine whether the prevalence rates or mean values of self- and parent-reported health indicators for children and adolescents aged 0-17 years differ between self-administered paper-based questionnaires (SAQ-paper) and self-administered Web-based questionnaires (SAQ-Web), as well as between a single-mode control group and different mixed-mode groups. Methods Data were collected for a methodological pilot of the third wave of the "German Health Interview and Examination Survey for Children and Adolescents". Questionnaires were completed by parents or adolescents. A population-based sample of 11,140 children and adolescents aged 0-17 years was randomly allocated to 4 survey designs—a single-mode control group with paper-and-pencil questionnaires only (n=970 parents, n=343 adolescents)—and 3 mixed-mode designs, all of which offered Web-based questionnaire options. In the concurrent mixed-mode design, both questionnaires were offered at the same time (n=946 parents, n=290 adolescents); in the sequential mixed-mode design, the SAQ-Web was sent first, followed by the paper questionnaire along with a reminder (n=854 parents, n=269 adolescents); and in the preselect mixed-mode design, both options were offered and the respondents were asked to request the desired type of questionnaire (n=698 parents, n=292 adolescents). In total, 3468 questionnaires of parents of children aged 0-17 years (SAQ-Web: n=708; SAQ-paper: n=2760) and 1194 questionnaires of adolescents aged 11-17 years (SAQ-Web: n=299; SAQ-paper: n=895) were analyzed. Sociodemographic characteristics and a broad

  17. Development of assessment methodology for plant configuration control

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Chang Hyun; You, Young Woo; Kim, Yoon Ik; Yang, Hui Chang; Huh, Byeong Gill; Lee, Dong Won; Ahn, Gwan Won [Seoul National Univ., Seoul (Korea, Republic of)

    2001-03-15

    The purpose of this study IS the development of effective and overall assessment methodology which reflects the characteristics of plants for the surveillance, maintenance, repair and operation of nuclear power plants. In this study, recent researches are surveyed and concept definition, procedures, current PSA methodologies, implementation of various models are evaluated. Through this survey, systematic assessment methodology is suggested. Configuration control assessment methodology suggested in this study for the purpose of the development of configuration control methodology reflecting the characteristics of Korean NPPs, can be utilized as the supplement of current PSA methodologies.

  18. Pseudo-populations a basic concept in statistical surveys

    CERN Document Server

    Quatember, Andreas

    2015-01-01

    This book emphasizes that artificial or pseudo-populations play an important role in statistical surveys from finite universes in two manners: firstly, the concept of pseudo-populations may substantially improve users’ understanding of various aspects in the sampling theory and survey methodology; an example of this scenario is the Horvitz-Thompson estimator. Secondly, statistical procedures exist in which pseudo-populations actually have to be generated. An example of such a scenario can be found in simulation studies in the field of survey sampling, where close-to-reality pseudo-populations are generated from known sample and population data to form the basis for the simulation process. The chapters focus on estimation methods, sampling techniques, nonresponse, questioning designs and statistical disclosure control.This book is a valuable reference in understanding the importance of the pseudo-population concept and applying it in teaching and research.

  19. Variable selection and estimation for longitudinal survey data

    KAUST Repository

    Wang, Li

    2014-09-01

    There is wide interest in studying longitudinal surveys where sample subjects are observed successively over time. Longitudinal surveys have been used in many areas today, for example, in the health and social sciences, to explore relationships or to identify significant variables in regression settings. This paper develops a general strategy for the model selection problem in longitudinal sample surveys. A survey weighted penalized estimating equation approach is proposed to select significant variables and estimate the coefficients simultaneously. The proposed estimators are design consistent and perform as well as the oracle procedure when the correct submodel was known. The estimating function bootstrap is applied to obtain the standard errors of the estimated parameters with good accuracy. A fast and efficient variable selection algorithm is developed to identify significant variables for complex longitudinal survey data. Simulated examples are illustrated to show the usefulness of the proposed methodology under various model settings and sampling designs. © 2014 Elsevier Inc.

  20. A sample of galaxy pairs identified from the LAMOST spectral survey and the Sloan Digital Sky Survey

    International Nuclear Information System (INIS)

    Shen, Shi-Yin; Argudo-Fernández, Maria; Chen, Li; Feng, Shuai; Hou, Jin-Liang; Shao, Zheng-Yi; Chen, Xiao-Yan; Luo, A-Li; Wu, Hong; Yang, Hai-Feng; Yang, Ming; Hou, Yong-Hui; Wang, Yue-Fei; Jiang, Peng; Wang, Ting-Gui; Jing, Yi-Peng; Kong, Xu; Wang, Wen-Ting; Luo, Zhi-Jian; Wu, Xue-Bing

    2016-01-01

    A small fraction (< 10%) of the SDSS main galaxy (MG) sample has not been targeted with spectroscopy due to the effect of fiber collisions. These galaxies have been compiled into the input catalog of the LAMOST ExtraGAlactic Surveys and named the complementary galaxy sample. In this paper, we introduce this project and status of the spectroscopies associated with the complementary galaxies in the first two years of the LAMOST spectral survey (till Sep. of 2014). Moreover, we present a sample of 1102 galaxy pairs identified from the LAMOST complementary galaxies and SDSS MGs, which are defined as two members that have a projected distance smaller than 100 h −1 70 kpc and a recessional velocity difference smaller than 500 km s −1 . Compared with galaxy pairs that are only selected from SDSS, the LAMOST-SDSS pairs have the advantages of not being biased toward large separations and therefore act as a useful supplement in statistical studies of galaxy interaction and galaxy merging. (paper)

  1. Use of methods for specifying the target difference in randomised controlled trial sample size calculations: Two surveys of trialists' practice.

    Science.gov (United States)

    Cook, Jonathan A; Hislop, Jennifer M; Altman, Doug G; Briggs, Andrew H; Fayers, Peter M; Norrie, John D; Ramsay, Craig R; Harvey, Ian M; Vale, Luke D

    2014-06-01

    Central to the design of a randomised controlled trial (RCT) is a calculation of the number of participants needed. This is typically achieved by specifying a target difference, which enables the trial to identify a difference of a particular magnitude should one exist. Seven methods have been proposed for formally determining what the target difference should be. However, in practice, it may be driven by convenience or some other informal basis. It is unclear how aware the trialist community is of these formal methods or whether they are used. To determine current practice regarding the specification of the target difference by surveying trialists. Two surveys were conducted: (1) Members of the Society for Clinical Trials (SCT): participants were invited to complete an online survey through the society's email distribution list. Respondents were asked about their awareness, use of, and willingness to recommend methods; (2) Leading UK- and Ireland-based trialists: the survey was sent to UK Clinical Research Collaboration registered Clinical Trials Units, Medical Research Council UK Hubs for Trial Methodology Research, and the Research Design Services of the National Institute for Health Research. This survey also included questions about the most recent trial developed by the respondent's group. Survey 1: Of the 1182 members on the SCT membership email distribution list, 180 responses were received (15%). Awareness of methods ranged from 69 (38%) for health economic methods to 162 (90%) for pilot study. Willingness to recommend among those who had used a particular method ranged from 56% for the opinion-seeking method to 89% for the review of evidence-base method. Survey 2: Of the 61 surveys sent out, 34 (56%) responses were received. Awareness of methods ranged from 33 (97%) for the review of evidence-base and pilot methods to 14 (41%) for the distribution method. The highest level of willingness to recommend among users was for the anchor method (87%). Based upon

  2. Radioimmunoassay of h-TSH - methodological suggestions for dealing with medium to large numbers of samples

    International Nuclear Information System (INIS)

    Mahlstedt, J.

    1977-01-01

    The article deals with practical aspects of establishing a TSH-RIA for patients, with particular regard to predetermined quality criteria. Methodological suggestions are made for medium to large numbers of samples with the target of reducing monotonous precision working steps by means of simple aids. The quality criteria required are well met, while the test procedure is well adapted to the rhythm of work and may be carried out without loss of precision even with large numbers of samples. (orig.) [de

  3. Development of assessment methodology for plant configuration control

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Chang Hyeon; Yu, Yeong Woo; Cho, Jae Seon; Kim, Ju Yeol; Kim, Yun Ik; Yang, Hui Chang; Park, Gang Min; Hur, Byeong Gil [Seoul National Univ., Seoul (Korea, Republic of)

    1999-03-15

    The purpose of this study is the development of effective and overall assessment methodology which reflects the characteristics of plants for the surveillance, maintenance, repair and operation of Nuclear Power Plant. The development of this methodology can contribute to enhance safety. In the first year of this study, recent researches are surveyed and concept definition, procedures, current PSA methodologies, implementation of various models are evaluated. Through this survey, systematic assessment methodology is suggested.

  4. Methodology for Quantitative Analysis of Large Liquid Samples with Prompt Gamma Neutron Activation Analysis using Am-Be Source

    International Nuclear Information System (INIS)

    Idiri, Z.; Mazrou, H.; Beddek, S.; Amokrane, A.

    2009-01-01

    An optimized set-up for prompt gamma neutron activation analysis (PGNAA) with Am-Be source is described and used for large liquid samples analysis. A methodology for quantitative analysis is proposed: it consists on normalizing the prompt gamma count rates with thermal neutron flux measurements carried out with He-3 detector and gamma attenuation factors calculated using MCNP-5. The relative and absolute methods are considered. This methodology is then applied to the determination of cadmium in industrial phosphoric acid. The same sample is then analyzed by inductively coupled plasma (ICP) method. Our results are in good agreement with those obtained with ICP method.

  5. Different methodologies in neutron activation to approach the full analysis of environmental and nutritional samples

    International Nuclear Information System (INIS)

    Freitas, M.C.; Dionisio, I.; Dung, H.M.

    2008-01-01

    Different methodologies of neutron activation analysis (NAA) are now available at the Technological and Nuclear Institute (Sacavem, Portugal), namely Compton suppression, epithermal activation, replicate and cyclic activation, and low energy photon measurement. Prompt gamma activation analysis (PGAA) will be implemented soon. Results by instrumental NAA and PGAA on environmental and nutritional samples are discussed herein, showing that PGAA - carried out at the Institute of Isotope Research (Budapest, Hungary) - brings about an effective input to assessing relevant elements. Sensitivity enhancement in NAA by Compton suppression is also illustrated. Through a judicious combination of methodologies, practically all elements of interest in pollution and nutrition terms can be determined. (author)

  6. Probability sampling design in ethnobotanical surveys of medicinal plants

    Directory of Open Access Journals (Sweden)

    Mariano Martinez Espinosa

    2012-07-01

    Full Text Available Non-probability sampling design can be used in ethnobotanical surveys of medicinal plants. However, this method does not allow statistical inferences to be made from the data generated. The aim of this paper is to present a probability sampling design that is applicable in ethnobotanical studies of medicinal plants. The sampling design employed in the research titled "Ethnobotanical knowledge of medicinal plants used by traditional communities of Nossa Senhora Aparecida do Chumbo district (NSACD, Poconé, Mato Grosso, Brazil" was used as a case study. Probability sampling methods (simple random and stratified sampling were used in this study. In order to determine the sample size, the following data were considered: population size (N of 1179 families; confidence coefficient, 95%; sample error (d, 0.05; and a proportion (p, 0.5. The application of this sampling method resulted in a sample size (n of at least 290 families in the district. The present study concludes that probability sampling methods necessarily have to be employed in ethnobotanical studies of medicinal plants, particularly where statistical inferences have to be made using data obtained. This can be achieved by applying different existing probability sampling methods, or better still, a combination of such methods.

  7. The U.S. Geological Survey Geologic Collections Management System (GCMS)—A master catalog and collections management plan for U.S. Geological Survey geologic samples and sample collections

    Science.gov (United States)

    ,

    2015-01-01

    The U.S. Geological Survey (USGS) is widely recognized in the earth science community as possessing extensive collections of earth materials collected by research personnel over the course of its history. In 2006, a Geologic Collections Inventory was conducted within the USGS Geology Discipline to determine the extent and nature of its sample collections, and in 2008, a working group was convened by the USGS National Geologic and Geophysical Data Preservation Program to examine ways in which these collections could be coordinated, cataloged, and made available to researchers both inside and outside the USGS. The charge to this working group was to evaluate the proposition of creating a Geologic Collections Management System (GCMS), a centralized database that would (1) identify all existing USGS geologic collections, regardless of size, (2) create a virtual link among the collections, and (3) provide a way for scientists and other researchers to obtain access to the samples and data in which they are interested. Additionally, the group was instructed to develop criteria for evaluating current collections and to establish an operating plan and set of standard practices for handling, identifying, and managing future sample collections. Policies and procedures promoted by the GCMS would be based on extant best practices established by the National Science Foundation and the Smithsonian Institution. The resulting report—USGS Circular 1410, “The U.S. Geological Survey Geologic Collections Management System (GCMS): A Master Catalog and Collections Management Plan for U.S. Geological Survey Geologic Samples and Sample Collections”—has been developed for sample repositories to be a guide to establishing common practices in the collection, retention, and disposal of geologic research materials throughout the USGS.

  8. Expectations for methodology and translation of animal research: a survey of health care workers.

    Science.gov (United States)

    Joffe, Ari R; Bara, Meredith; Anton, Natalie; Nobis, Nathan

    2015-05-07

    Health care workers (HCW) often perform, promote, and advocate use of public funds for animal research (AR); therefore, an awareness of the empirical costs and benefits of animal research is an important issue for HCW. We aim to determine what health-care-workers consider should be acceptable standards of AR methodology and translation rate to humans. After development and validation, an e-mail survey was sent to all pediatricians and pediatric intensive care unit nurses and respiratory-therapists (RTs) affiliated with a Canadian University. We presented questions about demographics, methodology of AR, and expectations from AR. Responses of pediatricians and nurses/RTs were compared using Chi-square, with P methodological quality, most respondents expect that: AR is done to high quality; costs and difficulty are not acceptable justifications for low quality; findings should be reproducible between laboratories and strains of the same species; and guidelines for AR funded with public money should be consistent with these expectations. Asked about benefits of AR, most thought that there are sometimes/often large benefits to humans from AR, and disagreed that "AR rarely produces benefit to humans." Asked about expectations of translation to humans (of toxicity, carcinogenicity, teratogenicity, and treatment findings), most: expect translation >40% of the time; thought that misleading AR results should occur methodological quality of, and the translation rate to humans of findings from AR. These expectations are higher than the empirical data show having been achieved. Unless these areas of AR significantly improve, HCW support of AR may be tenuous.

  9. Field screening sampling and analysis strategy and methodology for the 183-H Solar Evaporation Basins: Phase 2, Soils

    International Nuclear Information System (INIS)

    Antipas, A.; Hopkins, A.M.; Wasemiller, M.A.; McCain, R.G.

    1996-01-01

    This document provides a sampling/analytical strategy and methodology for Resource Conservation and Recovery Act (RCRA) closure of the 183-H Solar Evaporation Basins within the boundaries and requirements identified in the initial Phase II Sampling and Analysis Plan for RCRA Closure of the 183-H Solar Evaporation Basins

  10. 36 CFR 9.42 - Well records and reports, plots and maps, samples, tests and surveys.

    Science.gov (United States)

    2010-07-01

    ... Well records and reports, plots and maps, samples, tests and surveys. Any technical data gathered... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Well records and reports, plots and maps, samples, tests and surveys. 9.42 Section 9.42 Parks, Forests, and Public Property...

  11. The Carnegie-Spitzer-IMACS redshift survey of galaxy evolution since z = 1.5. I. Description and methodology

    Energy Technology Data Exchange (ETDEWEB)

    Kelson, Daniel D.; Williams, Rik J.; Dressler, Alan; McCarthy, Patrick J.; Shectman, Stephen A.; Mulchaey, John S.; Villanueva, Edward V.; Crane, Jeffrey D.; Quadri, Ryan F. [The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

    2014-03-10

    We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with the Inamori Magellan Areal Camera and Spectrograph (IMACS) on Magellan-Baade. By defining a flux-limited sample of galaxies in Spitzer Infrared Array Camera 3.6 μm imaging of SWIRE fields, the CSI Survey efficiently traces the stellar mass of average galaxies to z ∼ 1.5. This first paper provides an overview of the survey selection, observations, processing of the photometry and spectrophotometry. We also describe the processing of the data: new methods of fitting synthetic templates of spectral energy distributions are used to derive redshifts, stellar masses, emission line luminosities, and coarse information on recent star formation. Our unique methodology for analyzing low-dispersion spectra taken with multilayer prisms in IMACS, combined with panchromatic photometry from the ultraviolet to the IR, has yielded high-quality redshifts for 43,347 galaxies in our first 5.3 deg{sup 2} of the SWIRE XMM-LSS field. We use three different approaches to estimate our redshift errors and find robust agreement. Over the full range of 3.6 μm fluxes of our selection, we find typical redshift uncertainties of σ {sub z}/(1 + z) ≲ 0.015. In comparisons with previously published spectroscopic redshifts we find scatters of σ {sub z}/(1 + z) = 0.011 for galaxies at 0.7 ≤ z ≤ 0.9, and σ {sub z}/(1 + z) = 0.014 for galaxies at 0.9 ≤ z ≤ 1.2. For galaxies brighter and fainter than i = 23 mag, we find σ {sub z}/(1 + z) = 0.008 and σ {sub z}/(1 + z) = 0.022, respectively. Notably, our low-dispersion spectroscopy and analysis yields comparable redshift uncertainties and success rates for both red and blue galaxies, largely eliminating color-based systematics that can seriously bias observed dependencies of galaxy evolution on environment.

  12. Mode Equivalence of Health Indicators Between Data Collection Modes and Mixed-Mode Survey Designs in Population-Based Health Interview Surveys for Children and Adolescents: Methodological Study.

    Science.gov (United States)

    Mauz, Elvira; Hoffmann, Robert; Houben, Robin; Krause, Laura; Kamtsiuris, Panagiotis; Gößwald, Antje

    2018-03-05

    The implementation of an Internet option in an existing public health interview survey using a mixed-mode design is attractive because of lower costs and faster data availability. Additionally, mixed-mode surveys can increase response rates and improve sample composition. However, mixed-mode designs can increase the risk of measurement error (mode effects). This study aimed to determine whether the prevalence rates or mean values of self- and parent-reported health indicators for children and adolescents aged 0-17 years differ between self-administered paper-based questionnaires (SAQ-paper) and self-administered Web-based questionnaires (SAQ-Web), as well as between a single-mode control group and different mixed-mode groups. Data were collected for a methodological pilot of the third wave of the "German Health Interview and Examination Survey for Children and Adolescents". Questionnaires were completed by parents or adolescents. A population-based sample of 11,140 children and adolescents aged 0-17 years was randomly allocated to 4 survey designs-a single-mode control group with paper-and-pencil questionnaires only (n=970 parents, n=343 adolescents)-and 3 mixed-mode designs, all of which offered Web-based questionnaire options. In the concurrent mixed-mode design, both questionnaires were offered at the same time (n=946 parents, n=290 adolescents); in the sequential mixed-mode design, the SAQ-Web was sent first, followed by the paper questionnaire along with a reminder (n=854 parents, n=269 adolescents); and in the preselect mixed-mode design, both options were offered and the respondents were asked to request the desired type of questionnaire (n=698 parents, n=292 adolescents). In total, 3468 questionnaires of parents of children aged 0-17 years (SAQ-Web: n=708; SAQ-paper: n=2760) and 1194 questionnaires of adolescents aged 11-17 years (SAQ-Web: n=299; SAQ-paper: n=895) were analyzed. Sociodemographic characteristics and a broad range of health indicators for

  13. The impact of methodology in innovation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelmsen, L.; Bugge, M.; Solberg, E.

    2016-07-01

    Innovation surveys and rankings such as the Community Innovation Survey (CIS) and Innovation Union Scoreboard (IUS) have developed into influential diagnostic tools that are often used to categorize countries according to their innovation performance and to legitimise innovation policies. Although a number of ongoing processes are seeking to improve existing frameworks for measuring innovation, there are large methodological differences across countries in the way innovation is measured. This causes great uncertainty regarding a) the coherence between data from innovation surveys, b) actual innovativeness of the economy, and c) the validity of research based on innovation data. Against this background we explore empirically how different survey methods for measuring innovation affect reported innovation performance. The analysis is based on a statistical exercise comparing the results from three different methodological versions of the same survey for measuring innovation in the business enterprise sector in Norway. We find striking differences in reported innovation performance depending on how the surveys are carried out methodologically. The paper concludes that reported innovation performance is highly sensitive to and strongly conditioned by methodological context. This represents a need for increased caution and awareness around data collection and research based on innovation data, and not least in terms of aggregation of data and cross-country comparison. (Author)

  14. Dealing with trade-offs in destructive sampling designs for occupancy surveys.

    Directory of Open Access Journals (Sweden)

    Stefano Canessa

    Full Text Available Occupancy surveys should be designed to minimise false absences. This is commonly achieved by increasing replication or increasing the efficiency of surveys. In the case of destructive sampling designs, in which searches of individual microhabitats represent the repeat surveys, minimising false absences leads to an inherent trade-off. Surveyors can sample more low quality microhabitats, bearing the resultant financial costs and producing wider-spread impacts, or they can target high quality microhabitats were the focal species is more likely to be found and risk more severe impacts on local habitat quality. We show how this trade-off can be solved with a decision-theoretic approach, using the Millewa Skink Hemiergis millewae from southern Australia as a case study. Hemiergis millewae is an endangered reptile that is best detected using destructive sampling of grass hummocks. Within sites that were known to be occupied by H. millewae, logistic regression modelling revealed that lizards were more frequently detected in large hummocks. If this model is an accurate representation of the detection process, searching large hummocks is more efficient and requires less replication, but this strategy also entails destruction of the best microhabitats for the species. We developed an optimisation tool to calculate the minimum combination of the number and size of hummocks to search to achieve a given cumulative probability of detecting the species at a site, incorporating weights to reflect the sensitivity of the results to a surveyor's priorities. The optimisation showed that placing high weight on minimising volume necessitates impractical replication, whereas placing high weight on minimising replication requires searching very large hummocks which are less common and may be vital for H. millewae. While destructive sampling methods are sometimes necessary, surveyors must be conscious of the ecological impacts of these methods. This study provides a

  15. Methodology Series Module 5: Sampling Strategies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ' Sampling Method'. There are essentially two types of sampling methods: 1) probability sampling - based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling - based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ' random sample' when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ' generalizability' of these results. In such a scenario, the researcher may want to use ' purposive sampling' for the study.

  16. Methodology series module 5: Sampling strategies

    Directory of Open Access Journals (Sweden)

    Maninder Singh Setia

    2016-01-01

    Full Text Available Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the 'Sampling Method'. There are essentially two types of sampling methods: 1 probability sampling – based on chance events (such as random numbers, flipping a coin etc.; and 2 non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term 'random sample' when the researcher has used convenience sample. The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the 'generalizability' of these results. In such a scenario, the researcher may want to use 'purposive sampling' for the study.

  17. Global Tobacco Surveillance System (GTSS) - Global Youth Tobacco Survey (GYTS)

    Data.gov (United States)

    U.S. Department of Health & Human Services — 1999-2011. The GYTS is a school-based survey that collects data on students aged 13–15 years using a standardized methodology for constructing the sample frame,...

  18. Sample size reduction in groundwater surveys via sparse data assimilation

    KAUST Repository

    Hussain, Z.; Muhammad, A.

    2013-01-01

    In this paper, we focus on sparse signal recovery methods for data assimilation in groundwater models. The objective of this work is to exploit the commonly understood spatial sparsity in hydrodynamic models and thereby reduce the number of measurements to image a dynamic groundwater profile. To achieve this we employ a Bayesian compressive sensing framework that lets us adaptively select the next measurement to reduce the estimation error. An extension to the Bayesian compressive sensing framework is also proposed which incorporates the additional model information to estimate system states from even lesser measurements. Instead of using cumulative imaging-like measurements, such as those used in standard compressive sensing, we use sparse binary matrices. This choice of measurements can be interpreted as randomly sampling only a small subset of dug wells at each time step, instead of sampling the entire grid. Therefore, this framework offers groundwater surveyors a significant reduction in surveying effort without compromising the quality of the survey. © 2013 IEEE.

  19. Sample size reduction in groundwater surveys via sparse data assimilation

    KAUST Repository

    Hussain, Z.

    2013-04-01

    In this paper, we focus on sparse signal recovery methods for data assimilation in groundwater models. The objective of this work is to exploit the commonly understood spatial sparsity in hydrodynamic models and thereby reduce the number of measurements to image a dynamic groundwater profile. To achieve this we employ a Bayesian compressive sensing framework that lets us adaptively select the next measurement to reduce the estimation error. An extension to the Bayesian compressive sensing framework is also proposed which incorporates the additional model information to estimate system states from even lesser measurements. Instead of using cumulative imaging-like measurements, such as those used in standard compressive sensing, we use sparse binary matrices. This choice of measurements can be interpreted as randomly sampling only a small subset of dug wells at each time step, instead of sampling the entire grid. Therefore, this framework offers groundwater surveyors a significant reduction in surveying effort without compromising the quality of the survey. © 2013 IEEE.

  20. Can citizen science produce good science? Testing the OPAL Air Survey methodology, using lichens as indicators of nitrogenous pollution.

    Science.gov (United States)

    Tregidgo, Daniel J; West, Sarah E; Ashmore, Mike R

    2013-11-01

    Citizen science is having increasing influence on environmental monitoring as its advantages are becoming recognised. However methodologies are often simplified to make them accessible to citizen scientists. We tested whether a recent citizen science survey (the OPAL Air Survey) could detect trends in lichen community composition over transects away from roads. We hypothesised that the abundance of nitrophilic lichens would decrease with distance from the road, while that of nitrophobic lichens would increase. The hypothesised changes were detected along strong pollution gradients, but not where the road source was relatively weak, or background pollution relatively high. We conclude that the simplified OPAL methodology can detect large contrasts in nitrogenous pollution, but it may not be able to detect more subtle changes in pollution exposure. Similar studies are needed in conjunction with the ever-growing body of citizen science work to ensure that the limitations of these methods are fully understood. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Methodological integrative review of the work sampling technique used in nursing workload research.

    Science.gov (United States)

    Blay, Nicole; Duffield, Christine M; Gallagher, Robyn; Roche, Michael

    2014-11-01

    To critically review the work sampling technique used in nursing workload research. Work sampling is a technique frequently used by researchers and managers to explore and measure nursing activities. However, work sampling methods used are diverse making comparisons of results between studies difficult. Methodological integrative review. Four electronic databases were systematically searched for peer-reviewed articles published between 2002-2012. Manual scanning of reference lists and Rich Site Summary feeds from contemporary nursing journals were other sources of data. Articles published in the English language between 2002-2012 reporting on research which used work sampling to examine nursing workload. Eighteen articles were reviewed. The review identified that the work sampling technique lacks a standardized approach, which may have an impact on the sharing or comparison of results. Specific areas needing a shared understanding included the training of observers and subjects who self-report, standardization of the techniques used to assess observer inter-rater reliability, sampling methods and reporting of outcomes. Work sampling is a technique that can be used to explore the many facets of nursing work. Standardized reporting measures would enable greater comparison between studies and contribute to knowledge more effectively. Author suggestions for the reporting of results may act as guidelines for researchers considering work sampling as a research method. © 2014 John Wiley & Sons Ltd.

  2. Methodology Series Module 5: Sampling Strategies

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ‘ Sampling Method’. There are essentially two types of sampling methods: 1) probability sampling – based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ‘ random sample’ when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ‘ generalizability’ of these results. In such a scenario, the researcher may want to use ‘ purposive sampling’ for the study. PMID:27688438

  3. Research Note Pilot survey to assess sample size for herbaceous ...

    African Journals Online (AJOL)

    A pilot survey to determine sub-sample size (number of point observations per plot) for herbaceous species composition assessments, using a wheel-point apparatus applying the nearest-plant method, was conducted. Three plots differing in species composition on the Zululand coastal plain were selected, and on each plot ...

  4. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    International Nuclear Information System (INIS)

    Edjabou, Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn; Petersen, Claus; Scheutz, Charlotte; Astrup, Thomas Fruergaard

    2015-01-01

    Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

  5. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Edjabou, Maklawe Essonanawe, E-mail: vine@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Petersen, Claus [Econet AS, Omøgade 8, 2.sal, 2100 Copenhagen (Denmark); Scheutz, Charlotte; Astrup, Thomas Fruergaard [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2015-02-15

    Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

  6. Methodological Advances in Dea

    NARCIS (Netherlands)

    L. Cherchye (Laurens); G.T. Post (Thierry)

    2001-01-01

    textabstractWe survey the methodological advances in DEA over the last 25 years and discuss the necessary conditions for a sound empirical application. We hope this survey will contribute to the further dissemination of DEA, the knowledge of its relative strengths and weaknesses, and the tools

  7. EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY project: Design and methodology of the ENERGY cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Moreno Luis

    2011-01-01

    Full Text Available Abstract Background Obesity treatment is by large ineffective long term, and more emphasis on the prevention of excessive weight gain in childhood and adolescence is warranted. To inform energy balance related behaviour (EBRB change interventions, insight in the potential personal, family and school environmental correlates of these behaviours is needed. Studies on such multilevel correlates of EBRB among schoolchildren in Europe are lacking. The ENERGY survey aims to (1 provide up-to-date prevalence rates of measured overweight, obesity, self-reported engagement in EBRBs, and objective accelerometer-based assessment of physical activity and sedentary behaviour and blood-sample biomarkers of metabolic function in countries in different regions of Europe, (2 to identify personal, family and school environmental correlates of these EBRBs. This paper describes the design, methodology and protocol of the survey. Method/Design A school-based cross-sectional survey was carried out in 2010 in seven different European countries; Belgium, Greece, Hungary, the Netherlands, Norway, Slovenia, and Spain. The survey included measurements of anthropometrics, child, parent and school-staff questionnaires, and school observations to measure and assess outcomes (i.e. height, weight, and waist circumference, EBRBs and potential personal, family and school environmental correlates of these behaviours including the social-cultural, physical, political, and economic environmental factors. In addition, a selection of countries conducted accelerometer measurements to objectively assess physical activity and sedentary behaviour, and collected blood samples to assess several biomarkers of metabolic function. Discussion The ENERGY survey is a comprehensive cross-sectional study measuring anthropometrics and biomarkers as well as assessing a range of EBRBs and their potential correlates at the personal, family and school level, among 10-12 year old children in seven

  8. Sequential automated fusion/extraction chromatography methodology for the dissolution of uranium in environmental samples for mass spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Milliard, Alex; Durand-Jezequel, Myriam [Laboratoire de Radioecologie, Departement de chimie, Universite Laval, 1045 Avenue de la Medecine, Quebec, QC, G1V 0A6 (Canada); Lariviere, Dominic, E-mail: dominic.lariviere@chm.ulaval.ca [Laboratoire de Radioecologie, Departement de chimie, Universite Laval, 1045 Avenue de la Medecine, Quebec, QC, G1V 0A6 (Canada)

    2011-01-17

    An improved methodology has been developed, based on dissolution by automated fusion followed by extraction chromatography for the detection and quantification of uranium in environmental matrices by mass spectrometry. A rapid fusion protocol (<8 min) was investigated for the complete dissolution of various samples. It could be preceded, if required, by an effective ashing procedure using the M4 fluxer and a newly designed platinum lid. Complete dissolution of the sample was observed and measured using standard reference materials (SRMs) and experimental data show no evidence of cross-contamination of crucibles when LiBO{sub 2}/LiBr melts were used. The use of a M4 fusion unit also improved repeatability in sample preparation over muffle furnace fusion. Instrumental issues originating from the presence of high salt concentrations in the digestate after lithium metaborate fusion was also mitigated using an extraction chromatography (EXC) protocol aimed at removing lithium and interfering matrix constituants prior to the elution of uranium. The sequential methodology, which can be performed simultaneously on three samples, requires less than 20 min per sample for fusion and separation. It was successfully coupled to inductively coupled plasma mass spectrometry (ICP-MS) achieving detection limits below 100 pg kg{sup -1} for 5-300 mg of sample.

  9. Sampling effects on the identification of roadkill hotspots: Implications for survey design.

    Science.gov (United States)

    Santos, Sara M; Marques, J Tiago; Lourenço, André; Medinas, Denis; Barbosa, A Márcia; Beja, Pedro; Mira, António

    2015-10-01

    Although locating wildlife roadkill hotspots is essential to mitigate road impacts, the influence of study design on hotspot identification remains uncertain. We evaluated how sampling frequency affects the accuracy of hotspot identification, using a dataset of vertebrate roadkills (n = 4427) recorded over a year of daily surveys along 37 km of roads. "True" hotspots were identified using this baseline dataset, as the 500-m segments where the number of road-killed vertebrates exceeded the upper 95% confidence limit of the mean, assuming a Poisson distribution of road-kills per segment. "Estimated" hotspots were identified likewise, using datasets representing progressively lower sampling frequencies, which were produced by extracting data from the baseline dataset at appropriate time intervals (1-30 days). Overall, 24.3% of segments were "true" hotspots, concentrating 40.4% of roadkills. For different groups, "true" hotspots accounted from 6.8% (bats) to 29.7% (small birds) of road segments, concentrating from 60% (lizards, lagomorphs, carnivores) of roadkills. Spatial congruence between "true" and "estimated" hotspots declined rapidly with increasing time interval between surveys, due primarily to increasing false negatives (i.e., missing "true" hotspots). There were also false positives (i.e., wrong "estimated" hotspots), particularly at low sampling frequencies. Spatial accuracy decay with increasing time interval between surveys was higher for smaller-bodied (amphibians, reptiles, small birds, small mammals) than for larger-bodied species (birds of prey, hedgehogs, lagomorphs, carnivores). Results suggest that widely used surveys at weekly or longer intervals may produce poor estimates of roadkill hotspots, particularly for small-bodied species. Surveying daily or at two-day intervals may be required to achieve high accuracy in hotspot identification for multiple species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Who should be undertaking population-based surveys in humanitarian emergencies?

    Directory of Open Access Journals (Sweden)

    Spiegel Paul B

    2007-06-01

    Full Text Available Abstract Background Timely and accurate data are necessary to prioritise and effectively respond to humanitarian emergencies. 30-by-30 cluster surveys are commonly used in humanitarian emergencies because of their purported simplicity and reasonable validity and precision. Agencies have increasingly used 30-by-30 cluster surveys to undertake measurements beyond immunisation coverage and nutritional status. Methodological errors in cluster surveys have likely occurred for decades in humanitarian emergencies, often with unknown or unevaluated consequences. Discussion Most surveys in humanitarian emergencies are done by non-governmental organisations (NGOs. Some undertake good quality surveys while others have an already overburdened staff with limited epidemiological skills. Manuals explaining cluster survey methodology are available and in use. However, it is debatable as to whether using standardised, 'cookbook' survey methodologies are appropriate. Coordination of surveys is often lacking. If a coordinating body is established, as recommended, it is questionable whether it should have sole authority to release surveys due to insufficient independence. Donors should provide sufficient funding for personnel, training, and survey implementation, and not solely for direct programme implementation. Summary A dedicated corps of trained epidemiologists needs to be identified and made available to undertake surveys in humanitarian emergencies. NGOs in the field may need to form an alliance with certain specialised agencies or pool technically capable personnel. If NGOs continue to do surveys by themselves, a simple training manual with sample survey questionnaires, methodology, standardised files for data entry and analysis, and manual for interpretation should be developed and modified locally for each situation. At the beginning of an emergency, a central coordinating body should be established that has sufficient authority to set survey standards

  11. Methodology for the analysis of dietary data from the Mexican National Health and Nutrition Survey 2006.

    Science.gov (United States)

    Rodríguez-Ramírez, Sonia; Mundo-Rosas, Verónica; Jiménez-Aguilar, Alejandra; Shamah-Levy, Teresa

    2009-01-01

    To describe the methodology for the analysis of dietary data from the Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006) carried out in Mexico. Dietary data from the population who participated in the ENSANUT 2006 were collected through a 7-day food-frequency questionnaire. Energy and nutrient intake of each food consumed and adequacy percentage by day were also estimated. Intakes and adequacy percentages > 5 SDs from the energy and nutrient general distribution and observations with energy adequacy percentages < 25% were excluded from the analysis. Valid dietary data were obtained from 3552 children aged 1 to 4 years, 8716 children aged 5 to 11 years, 8442 adolescents, 15951 adults, and 3357 older adults. It is important to detail the methodology for the analysis of dietary data to standardize data cleaning criteria and to be able to compare the results of different studies.

  12. [Study of spatial stratified sampling strategy of Oncomelania hupensis snail survey based on plant abundance].

    Science.gov (United States)

    Xun-Ping, W; An, Z

    2017-07-27

    Objective To optimize and simplify the survey method of Oncomelania hupensis snails in marshland endemic regions of schistosomiasis, so as to improve the precision, efficiency and economy of the snail survey. Methods A snail sampling strategy (Spatial Sampling Scenario of Oncomelania based on Plant Abundance, SOPA) which took the plant abundance as auxiliary variable was explored and an experimental study in a 50 m×50 m plot in a marshland in the Poyang Lake region was performed. Firstly, the push broom surveyed data was stratified into 5 layers by the plant abundance data; then, the required numbers of optimal sampling points of each layer through Hammond McCullagh equation were calculated; thirdly, every sample point in the line with the Multiple Directional Interpolation (MDI) placement scheme was pinpointed; and finally, the comparison study among the outcomes of the spatial random sampling strategy, the traditional systematic sampling method, the spatial stratified sampling method, Sandwich spatial sampling and inference and SOPA was performed. Results The method (SOPA) proposed in this study had the minimal absolute error of 0.213 8; and the traditional systematic sampling method had the largest estimate, and the absolute error was 0.924 4. Conclusion The snail sampling strategy (SOPA) proposed in this study obtains the higher estimation accuracy than the other four methods.

  13. Methodology Series Module 5: Sampling Strategies

    OpenAIRE

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ? Sampling Method?. There are essentially two types of sampling methods: 1) probability sampling ? based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling ? based on researcher's choice, population that accessible & available. Some of the non-probabilit...

  14. Effects of various methodologic strategies: survey response rates among Canadian physicians and physicians-in-training.

    Science.gov (United States)

    Grava-Gubins, Inese; Scott, Sarah

    2008-10-01

    To increase the overall 2007 response rate of the National Physician Survey (NPS) from the survey's 2004 rate of response with the implementation of various methodologic strategies. Physicians were stratified to receive either a long version (12 pages) or a short version (6 pages) of the survey (38% and 62%, respectively). Mixed modes of contact were used-58% were contacted by e-mail and 42% by regular mail-with multiple modes of contact attempted for nonrespondents. The self-administered, confidential surveys were distributed in either English or French. Medical residents and students received e-mail surveys only and were offered a substantial monetary lottery incentive for completing their surveys. A professional communications firm assisted in marketing the survey and delivered advance notification of its impending distribution. Canada. A total of 62 441 practising physicians, 2627 second-year medical residents, and 9162 medical students in Canada. Of the practising physicians group, 60 811 participants were eligible and 19 239 replied, for an overall 2007 study response rate of 31.64% (compared with 35.85% in 2004). No difference in rate of response was found between the longer and shorter versions of the survey. If contacted by regular mail, the response rate was 34.1%; the e-mail group had a response rate of 29.9%. Medical student and resident response rates were 30.8% and 27.9%, respectively (compared with 31.2% and 35.6% in 2004). Despite shortening the questionnaires, contacting more physicians by e-mail, and enhancing marketing and follow-up, the 2007 NPS response rate for practising physicians did not surpass the 2004 NPS response rate. Offering a monetary lottery incentive to medical residents and students was also unsuccessful in increasing their response rates. The role of surveys in gathering information from physicians and physicians-in-training remains problematic. Researchers need to investigate alternative strategies for achieving higher rates of

  15. Conducting a respondent-driven sampling survey with the use of existing resources in Sydney, Australia.

    Science.gov (United States)

    Paquette, Dana M; Bryant, Joanne; Crawford, Sione; de Wit, John B F

    2011-07-01

    Respondent-driven sampling (RDS) is a form of chain-referral sampling that is increasingly being used for HIV behavioural surveillance. When used for surveillance purposes, a sampling method should be relatively inexpensive and simple to operate. This study examined whether an RDS survey of people who inject drugs (PWID) in Sydney, Australia, could be successfully conducted through the use of minimal and existing resources. The RDS survey was conducted on the premises of a local needle and syringe program (NSP) with some adjustments to take into account the constraints of existing resources. The impact of the survey on clients and on staff was examined by summarizing NSP service data and by conducting post-survey discussions with NSP staff. From November 2009 till March 2010, 261 participants were recruited in 16 waves. A significant increase was found in the number of services provided by the NSP during and after data collection. Generally, staff felt that the survey had a positive impact by exposing a broader group of people to the NSP. However, conducting the survey may have led to privacy issues for NSP clients due to an increased number of people gathering around the NSP. This study shows that RDS can be conducted with the use of minimal and existing resources under certain conditions (e.g., use of a self-administered questionnaire and no biological samples taken). A more detailed cost-utility analysis is needed to determine whether RDS' advantages outweigh potential challenges when compared to simpler and less costly convenience methods. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Spatial distribution, sampling precision and survey design optimisation with non-normal variables: The case of anchovy (Engraulis encrasicolus) recruitment in Spanish Mediterranean waters

    Science.gov (United States)

    Tugores, M. Pilar; Iglesias, Magdalena; Oñate, Dolores; Miquel, Joan

    2016-02-01

    In the Mediterranean Sea, the European anchovy (Engraulis encrasicolus) displays a key role in ecological and economical terms. Ensuring stock sustainability requires the provision of crucial information, such as species spatial distribution or unbiased abundance and precision estimates, so that management strategies can be defined (e.g. fishing quotas, temporal closure areas or marine protected areas MPA). Furthermore, the estimation of the precision of global abundance at different sampling intensities can be used for survey design optimisation. Geostatistics provide a priori unbiased estimations of the spatial structure, global abundance and precision for autocorrelated data. However, their application to non-Gaussian data introduces difficulties in the analysis in conjunction with low robustness or unbiasedness. The present study applied intrinsic geostatistics in two dimensions in order to (i) analyse the spatial distribution of anchovy in Spanish Western Mediterranean waters during the species' recruitment season, (ii) produce distribution maps, (iii) estimate global abundance and its precision, (iv) analyse the effect of changing the sampling intensity on the precision of global abundance estimates and, (v) evaluate the effects of several methodological options on the robustness of all the analysed parameters. The results suggested that while the spatial structure was usually non-robust to the tested methodological options when working with the original dataset, it became more robust for the transformed datasets (especially for the log-backtransformed dataset). The global abundance was always highly robust and the global precision was highly or moderately robust to most of the methodological options, except for data transformation.

  17. Which Methodology Works Better? English Language Teachers' Awareness of the Innovative Language Learning Methodologies

    Science.gov (United States)

    Kurt, Mustafa

    2015-01-01

    The present study investigated whether English language teachers were aware of the innovative language learning methodologies in language learning, how they made use of these methodologies and the learners' reactions to them. The descriptive survey method was employed to disclose the frequencies and percentages of 175 English language teachers'…

  18. An assessment of Lot Quality Assurance Sampling to evaluate malaria outcome indicators: extending malaria indicator surveys.

    Science.gov (United States)

    Biedron, Caitlin; Pagano, Marcello; Hedt, Bethany L; Kilian, Albert; Ratcliffe, Amy; Mabunda, Samuel; Valadez, Joseph J

    2010-02-01

    Large investments and increased global prioritization of malaria prevention and treatment have resulted in greater emphasis on programme monitoring and evaluation (M&E) in many countries. Many countries currently use large multistage cluster sample surveys to monitor malaria outcome indicators on a regional and national level. However, these surveys often mask local-level variability important to programme management. Lot Quality Assurance Sampling (LQAS) has played a valuable role for local-level programme M&E. If incorporated into these larger surveys, it would provide a comprehensive M&E plan at little, if any, extra cost. The Mozambique Ministry of Health conducted a Malaria Indicator Survey (MIS) in June and July 2007. We applied LQAS classification rules to the 345 sampled enumeration areas to demonstrate identifying high- and low-performing areas with respect to two malaria program indicators-'household possession of any bednet' and 'household possession of any insecticide-treated bednet (ITN)'. As shown by the MIS, no province in Mozambique achieved the 70% coverage target for household possession of bednets or ITNs. By applying LQAS classification rules to the data, we identify 266 of the 345 enumeration areas as having bednet coverage severely below the 70% target. An additional 73 were identified with low ITN coverage. This article demonstrates the feasibility of integrating LQAS into multistage cluster sampling surveys and using these results to support a comprehensive national, regional and local programme M&E system. Furthermore, in the recommendations we outlined how to integrate the Large Country-LQAS design into macro-surveys while still obtaining results available through current sampling practices.

  19. An algorithm to assess methodological quality of nutrition and mortality cross-sectional surveys: development and application to surveys conducted in Darfur, Sudan.

    Science.gov (United States)

    Prudhon, Claudine; de Radiguès, Xavier; Dale, Nancy; Checchi, Francesco

    2011-11-09

    Nutrition and mortality surveys are the main tools whereby evidence on the health status of populations affected by disasters and armed conflict is quantified and monitored over time. Several reviews have consistently revealed a lack of rigor in many surveys. We describe an algorithm for analyzing nutritional and mortality survey reports to identify a comprehensive range of errors that may result in sampling, response, or measurement biases and score quality. We apply the algorithm to surveys conducted in Darfur, Sudan. We developed an algorithm based on internationally agreed upon methods and best practices. Penalties are attributed for a list of errors, and an overall score is built from the summation of penalties accrued by the survey as a whole. To test the algorithm reproducibility, it was independently applied by three raters on 30 randomly selected survey reports. The algorithm was further applied to more than 100 surveys conducted in Darfur, Sudan. The Intra Class Correlation coefficient was 0.79 for mortality surveys and 0.78 for nutrition surveys. The overall median quality score and range of about 100 surveys conducted in Darfur were 0.60 (0.12-0.93) and 0.675 (0.23-0.86) for mortality and nutrition surveys, respectively. They varied between the organizations conducting the surveys, with no major trend over time. Our study suggests that it is possible to systematically assess quality of surveys and reveals considerable problems with the quality of nutritional and particularly mortality surveys conducted in the Darfur crisis.

  20. An empirical comparison of respondent-driven sampling, time location sampling, and snowball sampling for behavioral surveillance in men who have sex with men, Fortaleza, Brazil.

    Science.gov (United States)

    Kendall, Carl; Kerr, Ligia R F S; Gondim, Rogerio C; Werneck, Guilherme L; Macena, Raimunda Hermelinda Maia; Pontes, Marta Kerr; Johnston, Lisa G; Sabin, Keith; McFarland, Willi

    2008-07-01

    Obtaining samples of populations at risk for HIV challenges surveillance, prevention planning, and evaluation. Methods used include snowball sampling, time location sampling (TLS), and respondent-driven sampling (RDS). Few studies have made side-by-side comparisons to assess their relative advantages. We compared snowball, TLS, and RDS surveys of men who have sex with men (MSM) in Forteleza, Brazil, with a focus on the socio-economic status (SES) and risk behaviors of the samples to each other, to known AIDS cases and to the general population. RDS produced a sample with wider inclusion of lower SES than snowball sampling or TLS-a finding of health significance given the majority of AIDS cases reported among MSM in the state were low SES. RDS also achieved the sample size faster and at lower cost. For reasons of inclusion and cost-efficiency, RDS is the sampling methodology of choice for HIV surveillance of MSM in Fortaleza.

  1. Men who have sex with men in Great Britain: comparing methods and estimates from probability and convenience sample surveys

    Science.gov (United States)

    Prah, Philip; Hickson, Ford; Bonell, Chris; McDaid, Lisa M; Johnson, Anne M; Wayal, Sonali; Clifton, Soazig; Sonnenberg, Pam; Nardone, Anthony; Erens, Bob; Copas, Andrew J; Riddell, Julie; Weatherburn, Peter; Mercer, Catherine H

    2016-01-01

    Objective To examine sociodemographic and behavioural differences between men who have sex with men (MSM) participating in recent UK convenience surveys and a national probability sample survey. Methods We compared 148 MSM aged 18–64 years interviewed for Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) undertaken in 2010–2012, with men in the same age range participating in contemporaneous convenience surveys of MSM: 15 500 British resident men in the European MSM Internet Survey (EMIS); 797 in the London Gay Men's Sexual Health Survey; and 1234 in Scotland's Gay Men's Sexual Health Survey. Analyses compared men reporting at least one male sexual partner (past year) on similarly worded questions and multivariable analyses accounted for sociodemographic differences between the surveys. Results MSM in convenience surveys were younger and better educated than MSM in Natsal-3, and a larger proportion identified as gay (85%–95% vs 62%). Partner numbers were higher and same-sex anal sex more common in convenience surveys. Unprotected anal intercourse was more commonly reported in EMIS. Compared with Natsal-3, MSM in convenience surveys were more likely to report gonorrhoea diagnoses and HIV testing (both past year). Differences between the samples were reduced when restricting analysis to gay-identifying MSM. Conclusions National probability surveys better reflect the population of MSM but are limited by their smaller samples of MSM. Convenience surveys recruit larger samples of MSM but tend to over-represent MSM identifying as gay and reporting more sexual risk behaviours. Because both sampling strategies have strengths and weaknesses, methods are needed to triangulate data from probability and convenience surveys. PMID:26965869

  2. CONTAMINATED SOIL VOLUME ESTIMATE TRACKING METHODOLOGY

    International Nuclear Information System (INIS)

    Durham, L.A.; Johnson, R.L.; Rieman, C.; Kenna, T.; Pilon, R.

    2003-01-01

    The U.S. Army Corps of Engineers (USACE) is conducting a cleanup of radiologically contaminated properties under the Formerly Utilized Sites Remedial Action Program (FUSRAP). The largest cost element for most of the FUSRAP sites is the transportation and disposal of contaminated soil. Project managers and engineers need an estimate of the volume of contaminated soil to determine project costs and schedule. Once excavation activities begin and additional remedial action data are collected, the actual quantity of contaminated soil often deviates from the original estimate, resulting in cost and schedule impacts to the project. The project costs and schedule need to be frequently updated by tracking the actual quantities of excavated soil and contaminated soil remaining during the life of a remedial action project. A soil volume estimate tracking methodology was developed to provide a mechanism for project managers and engineers to create better project controls of costs and schedule. For the FUSRAP Linde site, an estimate of the initial volume of in situ soil above the specified cleanup guidelines was calculated on the basis of discrete soil sample data and other relevant data using indicator geostatistical techniques combined with Bayesian analysis. During the remedial action, updated volume estimates of remaining in situ soils requiring excavation were calculated on a periodic basis. In addition to taking into account the volume of soil that had been excavated, the updated volume estimates incorporated both new gamma walkover surveys and discrete sample data collected as part of the remedial action. A civil survey company provided periodic estimates of actual in situ excavated soil volumes. By using the results from the civil survey of actual in situ volumes excavated and the updated estimate of the remaining volume of contaminated soil requiring excavation, the USACE Buffalo District was able to forecast and update project costs and schedule. The soil volume

  3. Exploring School Counselors' Motivations to Work with LGBTQQI Students in Schools: A Q Methodology Study

    Science.gov (United States)

    Goodrich, Kristopher M.

    2017-01-01

    This study surveyed a national sample of school counselors who were members of ASCA to understand what motivated their work, or not, with lesbian, gay, bisexual, transgender, queer, questioning, and intersex (LGBTQQI) students in school. The author implemented Q methodology to collect and analyze the data, and results provide scholars and…

  4. Nationwide survey of radon levels in indoor workplaces in Mexico using Nuclear Track Methodology

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J.I.; Angeles, A.; Griffith, R.V.

    2009-01-01

    This report presents the preliminary results of an indoor workplace radon survey conducted during 2006-2007. Monitoring was carried out in 24 of the 32 federal entities of Mexico, incorporating 26 cities and 288 locations. The area monitored was divided into 8 regions for the purposes of the study: Chihuahua (a state with uranium mines), North-Central, South-Central, Southeast, South, Northeast, Northwest, and West. These regions differ in terms of geographic and geological characteristics, climate, altitude, and building materials and architectonic styles. Nuclear Track Methodology (NTM) was employed for the survey, using a passive closed-end cup device with Poly Allyl Diglycol Carbonate (PADC), known by its trade name CR-39 (Lantrack), as detector material. Well-established protocols for making continuous indoor radon measurements were followed, including one-step chemical etching in a 6.25 M KOH solution at 60 ± 1 deg. C with an etching time of 18 h. The track densities were determined with an automatic digital system at the Instituto de Fisica de la Universidad Nacional Autonoma de Mexico (IFUNAM) (Physics Institute of the National Autonomous University of Mexico), and calibrated in facilities at the Oak Ridge National Laboratory (ORNL). The importance of this survey lies in the fact that it represents the first time a nationwide survey of radon levels in indoor workplaces has been carried out in Mexico. Mean indoor radon levels from continuous measurements taken during and after working hours ranged from 13 Bq m -3 (the lower limit of detection) to 196 Bq m -3 . Analogous official controls or regulations for radon levels in indoor workplaces do not exist in Mexico. The survey described here contributes to knowledge of the natural radiological environment in workplaces, and will aid the relevant authorities in establishing appropriate regulations. The survey was made possible by the efforts of both a private institutions and the Dosimeter Application Project

  5. Scientists Admitting to Plagiarism: A Meta-analysis of Surveys.

    Science.gov (United States)

    Pupovac, Vanja; Fanelli, Daniele

    2015-10-01

    We conducted a systematic review and meta-analysis of anonymous surveys asking scientists whether they ever committed various forms of plagiarism. From May to December 2011 we searched 35 bibliographic databases, five grey literature databases and hand searched nine journals for potentially relevant studies. We included surveys that asked scientists if, in a given recall period, they had committed or knew of a colleague who committed plagiarism, and from each survey extracted the proportion of those who reported at least one case. Studies that focused on academic (i.e. student) plagiarism were excluded. Literature searches returned 12,460 titles from which 17 relevant survey studies were identified. Meta-analysis of studies reporting committed (N = 7) and witnessed (N = 11) plagiarism yielded a pooled estimate of, respectively, 1.7% (95% CI 1.2-2.4) and 30% (95% CI 17-46). Basic methodological factors, including sample size, year of survey, delivery method and whether survey questions were explicit rather than indirect made a significant difference on survey results. Even after controlling for these methodological factors, between-study differences in admission rates were significantly above those expected by sampling error alone and remained largely unexplained. Despite several limitations of the data and of this meta-analysis, we draw three robust conclusions: (1) The rate at which scientists report knowing a colleague who committed plagiarism is higher than for data fabrication and falsification; (2) The rate at which scientists report knowing a colleague who committed plagiarism is correlated to that of fabrication and falsification; (3) The rate at which scientists admit having committed either form of misconduct (i.e. fabrication, falsification and plagiarism) in surveys has declined over time.

  6. Men who have sex with men in Great Britain: comparing methods and estimates from probability and convenience sample surveys.

    Science.gov (United States)

    Prah, Philip; Hickson, Ford; Bonell, Chris; McDaid, Lisa M; Johnson, Anne M; Wayal, Sonali; Clifton, Soazig; Sonnenberg, Pam; Nardone, Anthony; Erens, Bob; Copas, Andrew J; Riddell, Julie; Weatherburn, Peter; Mercer, Catherine H

    2016-09-01

    To examine sociodemographic and behavioural differences between men who have sex with men (MSM) participating in recent UK convenience surveys and a national probability sample survey. We compared 148 MSM aged 18-64 years interviewed for Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) undertaken in 2010-2012, with men in the same age range participating in contemporaneous convenience surveys of MSM: 15 500 British resident men in the European MSM Internet Survey (EMIS); 797 in the London Gay Men's Sexual Health Survey; and 1234 in Scotland's Gay Men's Sexual Health Survey. Analyses compared men reporting at least one male sexual partner (past year) on similarly worded questions and multivariable analyses accounted for sociodemographic differences between the surveys. MSM in convenience surveys were younger and better educated than MSM in Natsal-3, and a larger proportion identified as gay (85%-95% vs 62%). Partner numbers were higher and same-sex anal sex more common in convenience surveys. Unprotected anal intercourse was more commonly reported in EMIS. Compared with Natsal-3, MSM in convenience surveys were more likely to report gonorrhoea diagnoses and HIV testing (both past year). Differences between the samples were reduced when restricting analysis to gay-identifying MSM. National probability surveys better reflect the population of MSM but are limited by their smaller samples of MSM. Convenience surveys recruit larger samples of MSM but tend to over-represent MSM identifying as gay and reporting more sexual risk behaviours. Because both sampling strategies have strengths and weaknesses, methods are needed to triangulate data from probability and convenience surveys. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  7. An algorithm to assess methodological quality of nutrition and mortality cross-sectional surveys: development and application to surveys conducted in Darfur, Sudan

    Directory of Open Access Journals (Sweden)

    Prudhon Claudine

    2011-11-01

    Full Text Available Abstract Background Nutrition and mortality surveys are the main tools whereby evidence on the health status of populations affected by disasters and armed conflict is quantified and monitored over time. Several reviews have consistently revealed a lack of rigor in many surveys. We describe an algorithm for analyzing nutritional and mortality survey reports to identify a comprehensive range of errors that may result in sampling, response, or measurement biases and score quality. We apply the algorithm to surveys conducted in Darfur, Sudan. Methods We developed an algorithm based on internationally agreed upon methods and best practices. Penalties are attributed for a list of errors, and an overall score is built from the summation of penalties accrued by the survey as a whole. To test the algorithm reproducibility, it was independently applied by three raters on 30 randomly selected survey reports. The algorithm was further applied to more than 100 surveys conducted in Darfur, Sudan. Results The Intra Class Correlation coefficient was 0.79 for mortality surveys and 0.78 for nutrition surveys. The overall median quality score and range of about 100 surveys conducted in Darfur were 0.60 (0.12-0.93 and 0.675 (0.23-0.86 for mortality and nutrition surveys, respectively. They varied between the organizations conducting the surveys, with no major trend over time. Conclusion Our study suggests that it is possible to systematically assess quality of surveys and reveals considerable problems with the quality of nutritional and particularly mortality surveys conducted in the Darfur crisis.

  8. Sampling methodology and PCB analysis

    International Nuclear Information System (INIS)

    Dominelli, N.

    1995-01-01

    As a class of compounds PCBs are extremely stable and resist chemical and biological decomposition. Diluted solutions exposed to a range of environmental conditions will undergo some preferential degradation and the resulting mixture may differ considerably from the original PCB used as insulating fluid in electrical equipment. The structure of mixtures of PCBs (synthetic compounds prepared by direct chlorination of biphenyl with chlorine gas) is extremely complex and presents a formidable analytical problem, further complicated by the presence of PCBs as contaminants in oils to soils to water. This paper provides some guidance into sampling and analytical procedures; it also points out various potential problems encountered during these processes. The guidelines provided deal with sample collection, storage and handling, sample stability, laboratory analysis (usually gas chromatography), determination of PCB concentration, calculation of total PCB content, and quality assurance. 1 fig

  9. Statistical Survey of Non-Formal Education

    Directory of Open Access Journals (Sweden)

    Ondřej Nývlt

    2012-12-01

    Full Text Available focused on a programme within a regular education system. Labour market flexibility and new requirements on employees create a new domain of education called non-formal education. Is there a reliable statistical source with a good methodological definition for the Czech Republic? Labour Force Survey (LFS has been the basic statistical source for time comparison of non-formal education for the last ten years. Furthermore, a special Adult Education Survey (AES in 2011 was focused on individual components of non-formal education in a detailed way. In general, the goal of the EU is to use data from both internationally comparable surveys for analyses of the particular fields of lifelong learning in the way, that annual LFS data could be enlarged by detailed information from AES in five years periods. This article describes reliability of statistical data aboutnon-formal education. This analysis is usually connected with sampling and non-sampling errors.

  10. Methodology for performing measurements to release material from radiological control

    International Nuclear Information System (INIS)

    Durham, J.S.; Gardner, D.L.

    1993-09-01

    This report describes the existing and proposed methodologies for performing measurements of contamination prior to releasing material for uncontrolled use at the Hanford Site. The technical basis for the proposed methodology, a modification to the existing contamination survey protocol, is also described. The modified methodology, which includes a large-area swipe followed by a statistical survey, can be used to survey material that is unlikely to be contaminated for release to controlled and uncontrolled areas. The material evaluation procedure that is used to determine the likelihood of contamination is also described

  11. The French national survey on food consumption of children under 3 years of age - Nutri-Bébé 2013: design, methodology, population sampling and feeding practices.

    Science.gov (United States)

    Chouraqui, Jean-Pierre; Tavoularis, Gabriel; Emery, Yves; Francou, Aurée; Hébel, Pascale; Bocquet, Magali; Hankard, Régis; Turck, Dominique

    2018-02-01

    To update the data on food consumption and practices in children under 3 years of age in metropolitan France. The Nutri-Bébé 2013 cross-sectional study selected a random sample, according to the quota sampling method. After giving their informed consent, parents had to record the food consumption during three non-consecutive days framed by two face-to-face interviews, using for quantitative information different portion size measurement aids. One thousand one hundred and eighty-four children were enrolled. Mothers' mean age was 30·8 (sd 5·4) years; 38 % were primiparous; 89 % lived with a partner; 60 % had an occupation. Of the infants younger than 4 months, 31 % were breast-fed. One thousand and thirty-five children consumed infant formula followed by growing-up milk in 63 % of them; solid foods were introduced at a mean age of 5·4 (sd 2·13) months. From 8 months onwards, 25 % of children consumed the same foods as their parents on a more or less regular basis; 29 % ate in front of a screen, with a daily average screen time of 43·0 (sd 40·4) min. This robust survey highlights the low prevalence and duration of breast-feeding in France and shows a modest improvement since the previous survey of 2005 in the observance of recommendations concerning other feeding practices. The frequent consumption of adult foods and the screen time are of concern.

  12. Methodological decisions and the evaluation of possible effects of different family structures on children: The new family structures survey (NFSS).

    Science.gov (United States)

    Schumm, Walter R

    2012-11-01

    Every social science researcher must make a number of methodological decisions when planning and implementing research projects. Each such decision carries with it both advantages and limitations. The decisions faced and made by Regnerus (2012) are discussed here in the wider context of social science literature regarding same-sex parenting. Even though the apparent outcomes of Regnerus's study were unpopular, the methodological decisions he made in the design and implementation of the New Family Structures Survey were not uncommon among social scientists, including many progressive, gay and lesbian scholars. These decisions and the research they produced deserve considerable and continued discussion, but criticisms of the underlying ethics and professionalism are misplaced because nearly every methodological decision that was made has ample precedents in research published by many other credible and distinguished scholars. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Basic Project Management Methodologies for Survey Researchers.

    Science.gov (United States)

    Beach, Robert H.

    To be effective, project management requires a heavy dependence on the document, list, and computational capability of a computerized environment. Now that microcomputers are readily available, only the rediscovery of classic project management methodology is required for improved resource allocation in small research projects. This paper provides…

  14. A Nationwide Random Sampling Survey of Potential Complicated Grief in Japan

    Science.gov (United States)

    Mizuno, Yasunao; Kishimoto, Junji; Asukai, Nozomu

    2012-01-01

    To investigate the prevalence of significant loss, potential complicated grief (CG), and its contributing factors, we conducted a nationwide random sampling survey of Japanese adults aged 18 or older (N = 1,343) using a self-rating Japanese-language version of the Complicated Grief Brief Screen. Among them, 37.0% experienced their most significant…

  15. Regional soil erosion assessment based on a sample survey and geostatistics

    Science.gov (United States)

    Yin, Shuiqing; Zhu, Zhengyuan; Wang, Li; Liu, Baoyuan; Xie, Yun; Wang, Guannan; Li, Yishan

    2018-03-01

    Soil erosion is one of the most significant environmental problems in China. From 2010 to 2012, the fourth national census for soil erosion sampled 32 364 PSUs (Primary Sampling Units, small watersheds) with the areas of 0.2-3 km2. Land use and soil erosion controlling factors including rainfall erosivity, soil erodibility, slope length, slope steepness, biological practice, engineering practice, and tillage practice for the PSUs were surveyed, and the soil loss rate for each land use in the PSUs was estimated using an empirical model, the Chinese Soil Loss Equation (CSLE). Though the information collected from the sample units can be aggregated to estimate soil erosion conditions on a large scale; the problem of estimating soil erosion condition on a regional scale has not been addressed well. The aim of this study is to introduce a new model-based regional soil erosion assessment method combining a sample survey and geostatistics. We compared seven spatial interpolation models based on the bivariate penalized spline over triangulation (BPST) method to generate a regional soil erosion assessment from the PSUs. Shaanxi Province (3116 PSUs) in China was selected for the comparison and assessment as it is one of the areas with the most serious erosion problem. Ten-fold cross-validation based on the PSU data showed the model assisted by the land use, rainfall erosivity factor (R), soil erodibility factor (K), slope steepness factor (S), and slope length factor (L) derived from a 1 : 10 000 topography map is the best one, with the model efficiency coefficient (ME) being 0.75 and the MSE being 55.8 % of that for the model assisted by the land use alone. Among four erosion factors as the covariates, the S factor contributed the most information, followed by K and L factors, and R factor made almost no contribution to the spatial estimation of soil loss. The LS factor derived from 30 or 90 m Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) data

  16. Improved sampling for airborne surveys to estimate wildlife population parameters in the African Savannah

    NARCIS (Netherlands)

    Khaemba, W.; Stein, A.

    2002-01-01

    Parameter estimates, obtained from airborne surveys of wildlife populations, often have large bias and large standard errors. Sampling error is one of the major causes of this imprecision and the occurrence of many animals in herds violates the common assumptions in traditional sampling designs like

  17. Web-based surveys as an alternative to traditional mail methods.

    Science.gov (United States)

    Fleming, Christopher M; Bowden, Mark

    2009-01-01

    Environmental economists have long used surveys to gather information about people's preferences. A recent innovation in survey methodology has been the advent of web-based surveys. While the Internet appears to offer a promising alternative to conventional survey administration modes, concerns exist over potential sampling biases associated with web-based surveys and the effect these may have on valuation estimates. This paper compares results obtained from a travel cost questionnaire of visitors to Fraser Island, Australia, that was conducted using two alternate survey administration modes; conventional mail and web-based. It is found that response rates and the socio-demographic make-up of respondents to the two survey modes are not statistically different. Moreover, both modes yield similar consumer surplus estimates.

  18. Adaptive geostatistical sampling enables efficient identification of malaria hotspots in repeated cross-sectional surveys in rural Malawi.

    Directory of Open Access Journals (Sweden)

    Alinune N Kabaghe

    Full Text Available In the context of malaria elimination, interventions will need to target high burden areas to further reduce transmission. Current tools to monitor and report disease burden lack the capacity to continuously detect fine-scale spatial and temporal variations of disease distribution exhibited by malaria. These tools use random sampling techniques that are inefficient for capturing underlying heterogeneity while health facility data in resource-limited settings are inaccurate. Continuous community surveys of malaria burden provide real-time results of local spatio-temporal variation. Adaptive geostatistical design (AGD improves prediction of outcome of interest compared to current random sampling techniques. We present findings of continuous malaria prevalence surveys using an adaptive sampling design.We conducted repeated cross sectional surveys guided by an adaptive sampling design to monitor the prevalence of malaria parasitaemia and anaemia in children below five years old in the communities living around Majete Wildlife Reserve in Chikwawa district, Southern Malawi. AGD sampling uses previously collected data to sample new locations of high prediction variance or, where prediction exceeds a set threshold. We fitted a geostatistical model to predict malaria prevalence in the area.We conducted five rounds of sampling, and tested 876 children aged 6-59 months from 1377 households over a 12-month period. Malaria prevalence prediction maps showed spatial heterogeneity and presence of hotspots-where predicted malaria prevalence was above 30%; predictors of malaria included age, socio-economic status and ownership of insecticide-treated mosquito nets.Continuous malaria prevalence surveys using adaptive sampling increased malaria prevalence prediction accuracy. Results from the surveys were readily available after data collection. The tool can assist local managers to target malaria control interventions in areas with the greatest health impact and is

  19. Multiresidual determination of pesticides in agricultural soil sample using Quechers extraction methodology

    International Nuclear Information System (INIS)

    Castro Garcia, Consuelo del Pilar

    2011-01-01

    To achieve a sustainable agricultural production there are used different organic and inorganic products, among them we found the fertilizers and pesticides. When they are applied most of the product falls to the ground, generating significant sources of pollution in the areas near the application and depending on the mobility of the pesticide, it can reach more remote areas. That is why it is important to determine the pesticide residues in soil after their application, being the selection of the extraction method crucial for the subsequent traces detection. In the present work there was evaluated the QUECHERS extraction technique, a method used in food but modified for a different and complex matrix like soil in order to achieve acceptable efficiencies multi-residue extraction of 20 pesticides and their subsequent determination by gas chromatography with electron capture and mass detection. The method was applied for the determination of pesticides in three soil samples from an agricultural site with different slopes between them. The Results indicated that 75% of the pesticides tested had acceptable efficiencies, thus meeting the objective of achieving multiresidue determination of pesticides in agricultural soil samples by extraction methodology QUECHERS. Besides, the presence of the fungicide penconazole was only detected in the three samples, being the highest concentration of pesticide found in the area with less slope (V_A_B_A_J_O) (author)

  20. Concrete crushing and sampling, a methodology and technology for the unconditional release of concrete material from decommissioning

    International Nuclear Information System (INIS)

    Gills, R.; Lewandowski, P.; Ooms, B.; Reusen, N.; Van Laer, W.; Walthery, R.

    2007-01-01

    Belgoprocess started the industrial decommissioning of the main process building of the former Eurochemic reprocessing plant in 1990, after completion of a pilot project. Two small storage buildings for final products from reprocessing were dismantled to verify the assumptions made in a previous paper study on decommissioning, to demonstrate and develop dismantling techniques and to train personnel. Both buildings were emptied and decontaminated to background levels. They were demolished and the remaining concrete debris was disposed of as industrial waste and green field conditions restored. Currently, the decommissioning operations carried out at the main building have made substantial progress. They are executed on an industrial scale. In view of the final demolition of the building, foreseen to start in the middle of 2008, a clearance methodology for the concrete from the cells into the Eurochemic building has been developed. It considers at least one complete measurement of all concrete structures and the removal of all detected residual radionuclides. This monitoring sequence is followed by a controlled demolition of the concrete structures and crushing of the resulting concrete parts to smaller particles. During the crushing operations, metal parts are separated from the concrete and representative concrete samples are taken. The frequency of sampling meets the prevailing standards. In a further step, the concrete samples are milled, homogenised, and a smaller fraction is sent to the laboratory for analyses. The paper describes the developed concrete crushing and sampling methodology. (authors)

  1. Field Report - Consumer Survey

    DEFF Research Database (Denmark)

    Nielsen, Kristian S.; Gwozdz, Wencke

    The present report outlines the purpose, scope, and methodology of a recently conducted four-country consumer survey that explored sustainable clothing consumption. The report also presents a sample of the descriptive findings from the survey (see Gwozdz, Nielsen & Müller, 2017 for further results...... foundation for upcoming deliverables relating to quality of life, acceptance of new business models, and consumer policy recommendations. The results presented in the report relate, specifically, to consumers’ general clothing consumption patterns, acceptance of new business models, and environmental...... purchasing outlets, and acceptance of new business models. Polish and American consumers purchased the most clothing items. Polish consumers also reported the lowest expenditures on clothing, whereas German consumers reported the highest expenditures. Only a limited proportion of consumers had previously...

  2. Sampling methods. A survey of methods in use in the Nordic countries

    International Nuclear Information System (INIS)

    Isaksson, M.

    2000-10-01

    This report is a survey of sampling techniques currently in use for radioactivity measurements in the Nordic countries, but restricted to sampling techniques for pasture, soil and deposition in emergency situations. It is found that the participating laboratories apply similar sampling procedures for pasture, including cutting height and size of sampled areas. Soil samples are generally taken by some sort of corer of different diameter. The number of cores taken varies, different sampling patterns are used, and pooling of the samples is done by some of the laboratories. The analysis of pasture and of soil is made with Nal-detectors or by high-resolution gamma spectrometry on fresh or dried samples. Precipitation collectors of a range of sizes are used to determine the activity concentration in precipitation and of dry deposited radionuclides. The analysis is made with high-resolution gamma-spectrometry, either directly on a water sample or on ion exchange resins. (au)

  3. CT dose survey in adults: what sample size for what precision?

    International Nuclear Information System (INIS)

    Taylor, Stephen; Muylem, Alain van; Howarth, Nigel; Gevenois, Pierre Alain; Tack, Denis

    2017-01-01

    To determine variability of volume computed tomographic dose index (CTDIvol) and dose-length product (DLP) data, and propose a minimum sample size to achieve an expected precision. CTDIvol and DLP values of 19,875 consecutive CT acquisitions of abdomen (7268), thorax (3805), lumbar spine (3161), cervical spine (1515) and head (4106) were collected in two centers. Their variabilities were investigated according to sample size (10 to 1000 acquisitions) and patient body weight categories (no weight selection, 67-73 kg and 60-80 kg). The 95 % confidence interval in percentage of their median (CI95/med) value was calculated for increasing sample sizes. We deduced the sample size that set a 95 % CI lower than 10 % of the median (CI95/med ≤ 10 %). Sample size ensuring CI95/med ≤ 10 %, ranged from 15 to 900 depending on the body region and the dose descriptor considered. In sample sizes recommended by regulatory authorities (i.e., from 10-20 patients), mean CTDIvol and DLP of one sample ranged from 0.50 to 2.00 times its actual value extracted from 2000 samples. The sampling error in CTDIvol and DLP means is high in dose surveys based on small samples of patients. Sample size should be increased at least tenfold to decrease this variability. (orig.)

  4. CT dose survey in adults: what sample size for what precision?

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Stephen [Hopital Ambroise Pare, Department of Radiology, Mons (Belgium); Muylem, Alain van [Hopital Erasme, Department of Pneumology, Brussels (Belgium); Howarth, Nigel [Clinique des Grangettes, Department of Radiology, Chene-Bougeries (Switzerland); Gevenois, Pierre Alain [Hopital Erasme, Department of Radiology, Brussels (Belgium); Tack, Denis [EpiCURA, Clinique Louis Caty, Department of Radiology, Baudour (Belgium)

    2017-01-15

    To determine variability of volume computed tomographic dose index (CTDIvol) and dose-length product (DLP) data, and propose a minimum sample size to achieve an expected precision. CTDIvol and DLP values of 19,875 consecutive CT acquisitions of abdomen (7268), thorax (3805), lumbar spine (3161), cervical spine (1515) and head (4106) were collected in two centers. Their variabilities were investigated according to sample size (10 to 1000 acquisitions) and patient body weight categories (no weight selection, 67-73 kg and 60-80 kg). The 95 % confidence interval in percentage of their median (CI95/med) value was calculated for increasing sample sizes. We deduced the sample size that set a 95 % CI lower than 10 % of the median (CI95/med ≤ 10 %). Sample size ensuring CI95/med ≤ 10 %, ranged from 15 to 900 depending on the body region and the dose descriptor considered. In sample sizes recommended by regulatory authorities (i.e., from 10-20 patients), mean CTDIvol and DLP of one sample ranged from 0.50 to 2.00 times its actual value extracted from 2000 samples. The sampling error in CTDIvol and DLP means is high in dose surveys based on small samples of patients. Sample size should be increased at least tenfold to decrease this variability. (orig.)

  5. A Unimodal Model for Double Observer Distance Sampling Surveys.

    Directory of Open Access Journals (Sweden)

    Earl F Becker

    Full Text Available Distance sampling is a widely used method to estimate animal population size. Most distance sampling models utilize a monotonically decreasing detection function such as a half-normal. Recent advances in distance sampling modeling allow for the incorporation of covariates into the distance model, and the elimination of the assumption of perfect detection at some fixed distance (usually the transect line with the use of double-observer models. The assumption of full observer independence in the double-observer model is problematic, but can be addressed by using the point independence assumption which assumes there is one distance, the apex of the detection function, where the 2 observers are assumed independent. Aerially collected distance sampling data can have a unimodal shape and have been successfully modeled with a gamma detection function. Covariates in gamma detection models cause the apex of detection to shift depending upon covariate levels, making this model incompatible with the point independence assumption when using double-observer data. This paper reports a unimodal detection model based on a two-piece normal distribution that allows covariates, has only one apex, and is consistent with the point independence assumption when double-observer data are utilized. An aerial line-transect survey of black bears in Alaska illustrate how this method can be applied.

  6. Understanding pathways of exposure using site-specific habits surveys, particularly new pathways and methodologies

    International Nuclear Information System (INIS)

    Grzechnik, M.; McTaggart, K.; Clyne, F.

    2006-01-01

    Full text of publication follows: UK policy on the control of radiation exposure via routine discharges from nuclear licensed sites has long been based on ICRP recommendations that embody the principles of justification of practices, optimisation of protection, and dose limitation. Radiological protection of the public is based on the concept of a critical group of individuals. This group is defined as those people who, as a result of the area they reside and their habits, receive the highest radiation dose due to the operations of a site. Therefore, if the dose to this critical group is acceptable in relation to relevant dose limits and constraints, then other members of the public will receive lower doses. Thus, the principle of critical groups provides overall protection for the public. Surveys to determine local habits involve an integrated methodology, whereby the potential radioactive exposure pathways from liquid and gaseous discharges and direct radiation from the site are investigated. Surveys to identify these habits must be undertaken rigorously for consistency, and have been known to reveal unexpected pathways of radiation exposure. Pathways typically include consumption of local foodstuffs and external exposure. Furthermore, a number of critical groups ma y be identified within a single survey area if the habits of one group do not adequately describe those of the other inhabitants of the area. Survey preparation involves the initial identification of high producers and consumers of local foods in a geographically defined area surrounding the nuclear facility. Pathways can be broken down into three general groups, which include exposure arising from; 1) Terrestrial (gaseous) discharges surveyed within 5 km of the site 2) Direct radiation surveyed within 1 km of the site 3) Aquatic (liquid) discharges surveyed within local areas affected by the discharges, including seas, rivers and sewage works. The survey fieldwork involves interviewing members of the

  7. Analytical methodologies for aluminium speciation in environmental and biological samples--a review.

    Science.gov (United States)

    Bi, S P; Yang, X D; Zhang, F P; Wang, X L; Zou, G W

    2001-08-01

    It is recognized that aluminium (Al) is a potential environmental hazard. Acidic deposition has been linked to increased Al concentrations in natural waters. Elevated levels of Al might have serious consequences for biological communities. Of particular interest is the speciation of Al in aquatic environments, because Al toxicity depends on its forms and concentrations. In this paper, advances in analytical methodologies for Al speciation in environmental and biological samples during the past five years are reviewed. Concerns about the specific problems of Al speciation and highlights of some important methods are elucidated in sections devoted to hybrid techniques (HPLC or FPLC coupled with ET-AAS, ICP-AES, or ICP-MS), flow-injection analysis (FIA), nuclear magnetic resonance (27Al NMR), electrochemical analysis, and computer simulation. More than 130 references are cited.

  8. CONSIDERATIONS ON THE METHODOLOGY FOR IDENTIFYING AND PRIORITIZING PUBLIC INVESTMENT PROJECTS IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Marilena BOGHEANU

    2012-01-01

    Full Text Available The optimization of the investment project pipeline of public administration is a key issue for member states, including Romania, in the current European Union policy. Solving this problem depends largely on the establishment of an appropriate methodological framework for identifying and prioritizing projects and development programs. Based on the new requirements imposed by the European Commission for the next financial cycle 2014-2020, in this article we propose solutions for improving the methodological framework by establishing general and specific criteria for evaluating projects, especially in the ex-ante stage.Our research is based on critical analysis of the current situation, including sample survey. The results obtained were materialized in an improved methodology for selecting and prioritizing projects that can contribute to a stable and uniform mechanism for planning at local level.

  9. New classification of natural breeding habitats for Neotropical anophelines in the Yanomami Indian Reserve, Amazon Region, Brazil and a new larval sampling methodology.

    Science.gov (United States)

    Sánchez-Ribas, Jordi; Oliveira-Ferreira, Joseli; Rosa-Freitas, Maria Goreti; Trilla, Lluís; Silva-do-Nascimento, Teresa Fernandes

    2015-09-01

    Here we present the first in a series of articles about the ecology of immature stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat classification and a new larval sampling methodology. We also report some preliminary results illustrating the applicability of the methodology based on data collected in the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami communities, Parafuri and Toototobi. In these areas, we mapped and classified 112 natural breeding habitats located in low-order river systems based on their association with river flood pulses, seasonality and exposure to sun. Our classification rendered seven types of larval habitats: lakes associated with the river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas associated with the river, flooded areas not associated with the river, rainfall pools, small forest streams, medium forest streams and rivers. The methodology for larval sampling was based on the accurate quantification of the effective breeding area, taking into account the area of the perimeter and subtypes of microenvironments present per larval habitat type using a laser range finder and a small portable inflatable boat. The new classification and new sampling methodology proposed herein may be useful in vector control programs.

  10. New classification of natural breeding habitats for Neotropical anophelines in the Yanomami Indian Reserve, Amazon Region, Brazil and a new larval sampling methodology

    Directory of Open Access Journals (Sweden)

    Jordi Sánchez-Ribas

    2015-09-01

    Full Text Available Here we present the first in a series of articles about the ecology of immature stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat classification and a new larval sampling methodology. We also report some preliminary results illustrating the applicability of the methodology based on data collected in the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami communities, Parafuri and Toototobi. In these areas, we mapped and classified 112 natural breeding habitats located in low-order river systems based on their association with river flood pulses, seasonality and exposure to sun. Our classification rendered seven types of larval habitats: lakes associated with the river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas associated with the river, flooded areas not associated with the river, rainfall pools, small forest streams, medium forest streams and rivers. The methodology for larval sampling was based on the accurate quantification of the effective breeding area, taking into account the area of the perimeter and subtypes of microenvironments present per larval habitat type using a laser range finder and a small portable inflatable boat. The new classification and new sampling methodology proposed herein may be useful in vector control programs.

  11. Basin Visual Estimation Technique (BVET) and Representative Reach Approaches to Wadeable Stream Surveys: Methodological Limitations and Future Directions

    Science.gov (United States)

    Lance R. Williams; Melvin L. Warren; Susan B. Adams; Joseph L. Arvai; Christopher M. Taylor

    2004-01-01

    Basin Visual Estimation Techniques (BVET) are used to estimate abundance for fish populations in small streams. With BVET, independent samples are drawn from natural habitat units in the stream rather than sampling "representative reaches." This sampling protocol provides an alternative to traditional reach-level surveys, which are criticized for their lack...

  12. Asking about Sex in General Health Surveys: Comparing the Methods and Findings of the 2010 Health Survey for England with Those of the Third National Survey of Sexual Attitudes and Lifestyles.

    Directory of Open Access Journals (Sweden)

    Philip Prah

    Full Text Available Including questions about sexual health in the annual Health Survey for England (HSE provides opportunities for regular measurement of key public health indicators, augmenting Britain's decennial National Survey of Sexual Attitudes and Lifestyles (Natsal. However, contextual and methodological differences may limit comparability of the findings. We examine the extent of these differences between HSE 2010 and Natsal-3 and investigate their impact on parameter estimates.Complex survey analyses of data from men and women in the 2010 HSE (n = 2,782 men and 3,588 women and Natsal-3 undertaken 2010-2012 (n = 4,882 men and 6,869 women aged 16-69y and resident in England, both using probability sampling, compared their characteristics, the amount of non-response to, and estimates from, sexual health questions. Both surveys used self-completion for the sexual behaviour questions but this was via computer-assisted self-interview (CASI in Natsal-3 and a pen-and-paper questionnaire in HSE 2010.The surveys achieved similar response rates, both around 60%, and demographic profiles largely consistent with the census, although HSE participants tended to be less educated, and reported worse general health, than Natsal-3 participants. Item non-response to the sexual health questions was typically higher in HSE 2010 (range: 9-18% relative to Natsal-3 (all <5%. Prevalence estimates for sexual risk behaviours and STI-related indicators were generally slightly lower in HSE 2010 than Natsal-3.While a relatively high response to sexual health questions in HSE 2010 demonstrates the feasibility of asking such questions in a general health survey, differences with Natsal-3 do exist. These are likely due to the HSE's context as a general health survey and methodological limitations such as its current use of pen-and-paper questionnaires. Methodological developments to the HSE should be considered so that its data can be interpreted in combination with those from dedicated

  13. Development of residential-conservation-survey methodology for the US Air Force. Interim report. Task two

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, D. W.; Hartman, T. L.; Lau, A. S.

    1981-11-13

    A US Air Force (USAF) Residential Energy Conservation Methodology was developed to compare USAF needs and available data to the procedures of the Residential Conservation Service (RCS) program as developed for general use by utility companies serving civilian customers. Attention was given to the data implications related to group housing, climatic data requirements, life-cycle cost analysis, energy saving modifications beyond those covered by RCS, and methods for utilizing existing energy consumption data in approaching the USAF survey program. Detailed information and summaries are given on the five subtasks of the program. Energy conservation alternatives are listed and the basic analysis techniques to be used in evaluating their thermal performane are described. (MCW)

  14. Sampling and analytical methodologies for energy dispersive X-ray fluorescence analysis of airborne particulate matter

    International Nuclear Information System (INIS)

    1993-01-01

    The present document represents an attempt to summarize the most important features of the different forms of ED-XFR as applied to the analysis of airborne particulate matter. It is intended to serve as a set of guidelines for use by participants in the IAEA's own programmes, and other scientists, who are not yet fully experienced in the application of ED-XRF to airborne particulate samples, and who wish either to make a start on using this technique or to improve their existing procedures. The methodologies for sampling described in this document are of rather general applicability. Emphasis is also placed on the sources of errors affecting the sampling of airborne particulate matter. The analytical part of the document describes the different forms of ED-XRF and their potential applications. Spectrum evaluation, a key step in X-ray spectrometry, is covered in depth, including discussion on several calibration and peak fitting techniques and computer programs especially designed for this purpose. 148 refs, 25 figs, 13 tabs

  15. Analytical Methodologies for the Determination of Endocrine Disrupting Compounds in Biological and Environmental Samples

    Directory of Open Access Journals (Sweden)

    Zoraida Sosa-Ferrera

    2013-01-01

    Full Text Available Endocrine-disruptor compounds (EDCs can mimic natural hormones and produce adverse effects in the endocrine functions by interacting with estrogen receptors. EDCs include both natural and synthetic chemicals, such as hormones, personal care products, surfactants, and flame retardants, among others. EDCs are characterised by their ubiquitous presence at trace-level concentrations and their wide diversity. Since the discovery of the adverse effects of these pollutants on wildlife and human health, analytical methods have been developed for their qualitative and quantitative determination. In particular, mass-based analytical methods show excellent sensitivity and precision for their quantification. This paper reviews recently published analytical methodologies for the sample preparation and for the determination of these compounds in different environmental and biological matrices by liquid chromatography coupled with mass spectrometry. The various sample preparation techniques are compared and discussed. In addition, recent developments and advances in this field are presented.

  16. National survey of residential magnetic field exposure

    International Nuclear Information System (INIS)

    Karipidis, K.K.

    2002-01-01

    The release of the Doll report in the UK, and its reported association between prolonged exposures to higher levels of power frequency magnetic fields and a small risk of leukaemia in children, has heightened community concerns. This disquiet among the general public has prompted the possibility of a national survey of residential magnetic field exposures to be implemented. Measurement methodologies were reviewed by the author and long-term measurements made by a logger placed in the living room for a 24-hour period were chosen as a surrogate measurement for the evaluation of exposure. An international comparison of similar surveys is presented, showing great deficiency, with the exception of Schuz et al and the UKCCS, in the number of homes surveyed. Factors influencing the selection of residences in the survey sample are elucidated and a range of sample sizes is presented with varying precision and confidence levels. Finally a feasible sample of 1,000 homes is chosen and a cost estimate is calculated with extra options for the measurement of the child's bedroom, a schools' survey and child personal exposure measurements included in the outlay. The purpose of the proposed national survey is to determine the proportion of Australian homes that are exposed to fields greater than 0.4 μT and the influence of proximity to powerlines as a cause. The study would also enable an interstate and international comparison of exposures to be made. Copyright (2002) Australasian Radiation Protection Society Inc

  17. The economic impact of poor sample quality in clinical chemistry laboratories: results from a global survey.

    Science.gov (United States)

    Erdal, Erik P; Mitra, Debanjali; Khangulov, Victor S; Church, Stephen; Plokhoy, Elizabeth

    2017-03-01

    Background Despite advances in clinical chemistry testing, poor blood sample quality continues to impact laboratory operations and the quality of results. While previous studies have identified the preanalytical causes of lower sample quality, few studies have examined the economic impact of poor sample quality on the laboratory. Specifically, the costs associated with workarounds related to fibrin and gel contaminants remain largely unexplored. Methods A quantitative survey of clinical chemistry laboratory stakeholders across 10 international regions, including countries in North America, Europe and Oceania, was conducted to examine current blood sample testing practices, sample quality issues and practices to remediate poor sample quality. Survey data were used to estimate costs incurred by laboratories to mitigate sample quality issues. Results Responses from 164 participants were included in the analysis, which was focused on three specific issues: fibrin strands, fibrin masses and gel globules. Fibrin strands were the most commonly reported issue, with an overall incidence rate of ∼3%. Further, 65% of respondents indicated that these issues contribute to analyzer probe clogging, and the majority of laboratories had visual inspection and manual remediation practices in place to address fibrin- and gel-related quality problems (55% and 70%, respectively). Probe maintenance/replacement, visual inspection and manual remediation were estimated to carry significant costs for the laboratories surveyed. Annual cost associated with lower sample quality and remediation related to fibrin and/or gel globules for an average US laboratory was estimated to be $100,247. Conclusions Measures to improve blood sample quality present an important step towards improved laboratory operations.

  18. Methodology of the fasting sub-sample from the Mexican Health Survey, 2000 Metodología de la submuestra de suero de la Encuesta Nacional de Salud 2000

    Directory of Open Access Journals (Sweden)

    Simón Barquera

    2007-01-01

    Full Text Available OBJECTIVE: To report the comparative results of the sub-sample of fasting adults selected for the biochemical measurement of cardiovascular risk factors and the rest of the Mexican Health Survey (MHS (2000 participants. MATERIAL AND METHODS: The nationally representative, cross-sectional Mexican Health Survey (2000 was analyzed. Survey participants reporting a fasting state period of 9- to 12-h were included in a sub-sample (n= 2 535 and compared with all other participants (n= 41 126. Prevalence and 95% confidence intervals (95%CI were calculated for socio-demographic, anthropometric, health and personal background characteristics and compared between groups using Pearson chi2 to determine significant differences. Mean and 95%CI and a T-test were calculated to analyze continuous variables. RESULTS: From the 45 294 adults participating in the MHS, 5.59% were at fasting state. The fasting sub-sample (FS had a higher male-to-female ratio and was on average 3.5 years younger than the non-fasting participants (NF and had a 1.5cm wider average waist circumference. No differences were found in location, country region, socio-economic status, indigenous population, or literacy. Also, no differences were found in weight, height, BMI, systolic and diastolic blood pressure, prevalence of diabetes mellitus, previous medical diagnosis of dislypidemias, or tobacco or alcohol consumption. CONCLUSION: This paper documents the characteristics of the fasting sub-sample from the Mexican Health Survey (MHS. Overall, the non-fasting participants had no relevant differences that can contribute to generate biased results in the analysis of biochemical indicators of cardiovascular risk.OBJETIVO: Reportar los resultados comparativos de la sub-muestra de adultos en ayuno, seleccionados para la medición bioquímica de factores de riesgo cardiovascular y el resto de los participantes de la Encuesta Nacional de Salud (ENSA 2000. MATERIAL Y MÉTODOS: Se analizó la ENSA

  19. APPLICATION OF LOT QUALITY ASSURANCE SAMPLING FOR ASSESSING DISEASE CONTROL PROGRAMMES - EXAMINATION OF SOME METHODOLOGICAL ISSUES

    OpenAIRE

    T. R. RAMESH RAO

    2011-01-01

    Lot Quality Assurance Sampling (LQAS), a statistical tool in industrial setup, has been in use since 1980 for monitoring and evaluation of programs on disease control / immunization status among children / health workers performance in health system. While conducting LQAS in the field, there are occasions, even after due care of design, there are practical and methodological issues to be addressed before it is recommended for implementation and intervention. LQAS is applied under the assumpti...

  20. Shorlist Masterplan Wind. Evaluation of the sampling grid of the year-round ichthyoplankton survey

    NARCIS (Netherlands)

    Bolle, L.J.; Beek, van J.K.L.

    2011-01-01

    Within the research programme 'Shortlist Masterplan Wind' a year-round ichthyoplankton survey is being carried out. The sampling area is based on known spawning concentrations and prevailing currents.

  1. Assessment of mental health and illness by telephone survey: experience with an Alberta mental health survey.

    Science.gov (United States)

    Patten, Scott B; Adair, Carol E; Williams, Jeanne Va; Brant, Rollin; Wang, Jian Li; Casebeer, Ann; Beauséjour, Pierre

    2006-01-01

    Mental health is an emerging priority for health surveillance. It has not been determined that the existing data sources can adequately meet surveillance needs. The objective of this project was to explore the use of telephone surveys as a means of collecting supplementary surveillance information. A computer-assisted telephone interview was administered to 5,400 subjects in Alberta. The interview included a set of brief, validated measures for evaluating mental disorder prevalence and related variables. The individual subject response rate was 78 percent, but a substantial number of refusals occurred at the initial household contact. The age and sex distribution of the study sample differed from that of the provincial population prior to weighting. Prevalence proportions did not vary substantially across administrative health regions. There is a potential role for telephone data collection in mental health surveillance, but these results highlight some associated methodological challenges. They also draw into question the importance of regional variation in mental disorder prevalence--which might otherwise have been a key advantage of telephone survey methodologies.

  2. A survey of archaeological and geological samples dated in 1990

    International Nuclear Information System (INIS)

    Mejdahl, V.

    1991-01-01

    A survey of dated archaeological and geological samples is given, using thermoluminescence dating. Some of the sediment samples were also dated by means of optically stimulated luminescence (OSL) using a newly developed infrared diode system. In most cases the luminescence dates are in accordance with archaeological and geological estimates. Some discrepancies were found because some feldspar samples exhibited severe anomalous fading. It may be possible to avoid this problem by basing the dating on OSL of quartz. For sediment samples of Eemian or Early Weichselian age severe underestimates were encountered with both methods. The reason might be related to the large difference between the natural dose rate and that used in laboratory irradiations. Traps corresponding to low-temperature peaks such as the 150 deg. C peak in feldspars will remain almost empty under natural conditions, but will fill up to saturation under laboratory irradiation and thereby more charges will be captured in high-temperature traps. As a result, natural growth curves and laboratory produced luminescence growth curves will have different slopes and this will lead to underestimation. This problem might avoided by holding samples at an elevated temperature during laboratory irradiation, thus keeping the low-temperature traps empty. Preliminary experiments where feldspar samples were held at 130 deg. C during irradiation have given promising results. (AB) (31 refs.)

  3. Hospital survey on patient safety culture: psychometric analysis on a Scottish sample.

    Science.gov (United States)

    Sarac, Cakil; Flin, Rhona; Mearns, Kathryn; Jackson, Jeanette

    2011-10-01

    To investigate the psychometric properties of the Hospital Survey on Patient Safety Culture on a Scottish NHS data set. The data were collected from 1969 clinical staff (estimated 22% response rate) from one acute hospital from each of seven Scottish Health boards. Using a split-half validation technique, the data were randomly split; an exploratory factor analysis was conducted on the calibration data set, and confirmatory factor analyses were conducted on the validation data set to investigate and check the original US model fit in a Scottish sample. Following the split-half validation technique, exploratory factor analysis results showed a 10-factor optimal measurement model. The confirmatory factor analyses were then performed to compare the model fit of two competing models (10-factor alternative model vs 12-factor original model). An S-B scaled χ(2) square difference test demonstrated that the original 12-factor model performed significantly better in a Scottish sample. Furthermore, reliability analyses of each component yielded satisfactory results. The mean scores on the climate dimensions in the Scottish sample were comparable with those found in other European countries. This study provided evidence that the original 12-factor structure of the Hospital Survey on Patient Safety Culture scale has been replicated in this Scottish sample. Therefore, no modifications are required to the original 12-factor model, which is suggested for use, since it would allow researchers the possibility of cross-national comparisons.

  4. Is a 'convenience' sample useful for estimating immunization coverage in a small population?

    Science.gov (United States)

    Weir, Jean E; Jones, Carrie

    2008-01-01

    Rapid survey methodologies are widely used for assessing immunization coverage in developing countries, approximating true stratified random sampling. Non-random ('convenience') sampling is not considered appropriate for estimating immunization coverage rates but has the advantages of low cost and expediency. We assessed the validity of a convenience sample of children presenting to a travelling clinic by comparing the coverage rate in the convenience sample to the true coverage established by surveying each child in three villages in rural Papua New Guinea. The rate of DTF immunization coverage as estimated by the convenience sample was within 10% of the true coverage when the proportion of children in the sample was two-thirds or when only children over the age of one year were counted, but differed by 11% when the sample included only 53% of the children and when all eligible children were included. The convenience sample may be sufficiently accurate for reporting purposes and is useful for identifying areas of low coverage.

  5. Technical bases and guidance for the use of composite soil sampling for demonstrating compliance with radiological release criteria

    International Nuclear Information System (INIS)

    Vitkus, Timothy J.

    2012-01-01

    This guidance provides information on methodologies and the technical bases that licensees should consider for incorporating composite sampling strategies into final status survey (FSS) plans. In addition, this guidance also includes appropriate uses of composite sampling for generating the data for other decommissioning site investigations such as characterization or other preliminary site investigations

  6. Technical bases and guidance for the use of composite soil sampling for demonstrating compliance with radiological release criteria

    Energy Technology Data Exchange (ETDEWEB)

    Vitkus, Timothy J. [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2012-04-24

    This guidance provides information on methodologies and the technical bases that licensees should consider for incorporating composite sampling strategies into final status survey (FSS) plans. In addition, this guidance also includes appropriate uses of composite sampling for generating the data for other decommissioning site investigations such as characterization or other preliminary site investigations.

  7. 2012 Workplace and Gender Relations Survey of Reserve Component Members: Statistical Methodology Report

    Science.gov (United States)

    2012-09-01

    3,435 10,461 9.1 3.1 63 Unmarried with Children+ Unmarried without Children 439,495 0.01 10,350 43,870 10.1 2.2 64 Married with Children+ Married ...logistic regression model was used to predict the probability of eligibility for the survey (known eligibility vs . unknown eligibility). A second logistic...regression model was used to predict the probability of response among eligible sample members (complete response vs . non-response). CHAID (Chi

  8. The measurement invariance of job diagnostic survey (JDS across three university student groups

    Directory of Open Access Journals (Sweden)

    Monica Martinez-Gomez

    2016-02-01

    Full Text Available Purpose: The main purpose of this study is to apply a multigroup confirmatory analysis to examine the measurement invariance (MI of the adapted version of the Job Diagnosis Survey (JDS as a measurement tool that analyses the relationship between the features of teaching methodologies with university students’ motivation and satisfaction across data collected on different degrees and academic years. Design/methodology/approach: Confirmatory factor analysis was carried out using a multigroup structural equation model, using the program EQS 6.1 to test the invariance of the adapted version of JDS in a sample constituted by 535 student of a Spanish public university. The assessment of invariance included the levels of configural, metric, scalar, covariance and latent variables invariance. Several goodness-of-fit measures were assessed. Findings: The results show that measurements are equivalent at the configural, metric, covariance and latent factors invariance. Although the hypotheses of scalar invariance is rejected, results suggest that JDS is partial strict invariant and has satisfactory psychometric properties on all samples. Research limitations/implications: The sample is framed in university students aged between 18 and 30 and for a questionnaire on teaching methodology and students' satisfaction in the context of a Spanish university and the generalization to other questionnaire, or population, should be proved with specific data. Furthermore, the sample size is rather small. Originality/value: In the current process of change that is taking place in universities according to the plan developed by the European Space of Higher Education, focused on increasing the student skills, validate instruments as the satisfaction scale of JDS, are necessary to evaluate students’ satisfaction with new active methodologies. These findings are useful for researchers since they add the first sample in which the MI of a student’s satisfaction survey

  9. A cross-sectional survey of 5-year-old children with non-syndromic unilateral cleft lip and palate: the Cleft Care UK study. Part 1: background and methodology.

    Science.gov (United States)

    Persson, M; Sandy, J R; Waylen, A; Wills, A K; Al-Ghatam, R; Ireland, A J; Hall, A J; Hollingworth, W; Jones, T; Peters, T J; Preston, R; Sell, D; Smallridge, J; Worthington, H; Ness, A R

    2015-11-01

    We describe the methodology for a major study investigating the impact of reconfigured cleft care in the United Kingdom (UK) 15 years after an initial survey, detailed in the Clinical Standards Advisory Group (CSAG) report in 1998, had informed government recommendations on centralization. This is a UK multicentre cross-sectional study of 5-year-olds born with non-syndromic unilateral cleft lip and palate. Children born between 1 April 2005 and 31 March 2007 were seen in cleft centre audit clinics. Consent was obtained for the collection of routine clinical measures (speech recordings, hearing, photographs, models, oral health, psychosocial factors) and anthropometric measures (height, weight, head circumference). The methodology for each clinical measure followed those of the earlier survey as closely as possible. We identified 359 eligible children and recruited 268 (74.7%) to the study. Eleven separate records for each child were collected at the audit clinics. In total, 2666 (90.4%) were collected from a potential 2948 records. The response rates for the self-reported questionnaires, completed at home, were 52.6% for the Health and Lifestyle Questionnaire and 52.2% for the Satisfaction with Service Questionnaire. Response rates and measures were similar to those achieved in the previous survey. There are practical, administrative and methodological challenges in repeating cross-sectional surveys 15 years apart and producing comparable data. © 2015 The Authors. Orthodontics & Craniofacial Research Published by John Wiley & Sons Ltd.

  10. Methodology for Validating Building Energy Analysis Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Judkoff, R.; Wortman, D.; O' Doherty, B.; Burch, J.

    2008-04-01

    The objective of this report was to develop a validation methodology for building energy analysis simulations, collect high-quality, unambiguous empirical data for validation, and apply the validation methodology to the DOE-2.1, BLAST-2MRT, BLAST-3.0, DEROB-3, DEROB-4, and SUNCAT 2.4 computer programs. This report covers background information, literature survey, validation methodology, comparative studies, analytical verification, empirical validation, comparative evaluation of codes, and conclusions.

  11. Human-Robot Site Survey and Sampling for Space Exploration

    Science.gov (United States)

    Fong, Terrence; Bualat, Maria; Edwards, Laurence; Flueckiger, Lorenzo; Kunz, Clayton; Lee, Susan Y.; Park, Eric; To, Vinh; Utz, Hans; Ackner, Nir

    2006-01-01

    NASA is planning to send humans and robots back to the Moon before 2020. In order for extended missions to be productive, high quality maps of lunar terrain and resources are required. Although orbital images can provide much information, many features (local topography, resources, etc) will have to be characterized directly on the surface. To address this need, we are developing a system to perform site survey and sampling. The system includes multiple robots and humans operating in a variety of team configurations, coordinated via peer-to-peer human-robot interaction. In this paper, we present our system design and describe planned field tests.

  12. Small-vessel Survey and Auction Sampling to Estimate Growth and Maturity of Eteline Snappers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Small-vessel Survey and Auction Sampling to Estimate Growth and Maturity of Eteline Snappers and Improve Data-Limited Stock Assessments. This biosampling project...

  13. Standardization of a PIGE methodology for simultaneous quantification of low Z elements in barium borosilicate glass samples

    International Nuclear Information System (INIS)

    Chhillar, S.; Acharya, R.; Dasari, K.B.; Pujari, P.K.; Mishra, R.K.; Kaushik, C.P.

    2013-01-01

    In order to standardize particle induced gamma-ray emission (PIGE) methodology for simultaneous quantification of light elements, analytical sensitivities of Li, F, B, Na, Al and Si were evaluated using 4 MeV proton beam ( ∼ 10 nA current) using 3 MV Pelletron at IOP, Bhubaneswar. The PIGE method was validated by determining all six elements in a synthetic sample in graphite matrix and applied to two barium borosilicate glass (BaBSG) samples. The prompt γ-rays emitted from inelastic scattering or nuclear reactions of corresponding isotopes were measured using a 60% HPGe coupled to MCA and the current normalized count rates were used for concentration calculation. (author)

  14. Dark Energy Survey Year 1 Results: Methodology and Projections for Joint Analysis of Galaxy Clustering, Galaxy Lensing, and CMB Lensing Two-point Functions

    Energy Technology Data Exchange (ETDEWEB)

    Giannantonio, T.; et al.

    2018-02-14

    Optical imaging surveys measure both the galaxy density and the gravitational lensing-induced shear fields across the sky. Recently, the Dark Energy Survey (DES) collaboration used a joint fit to two-point correlations between these observables to place tight constraints on cosmology (DES Collaboration et al. 2017). In this work, we develop the methodology to extend the DES Collaboration et al. (2017) analysis to include cross-correlations of the optical survey observables with gravitational lensing of the cosmic microwave background (CMB) as measured by the South Pole Telescope (SPT) and Planck. Using simulated analyses, we show how the resulting set of five two-point functions increases the robustness of the cosmological constraints to systematic errors in galaxy lensing shear calibration. Additionally, we show that contamination of the SPT+Planck CMB lensing map by the thermal Sunyaev-Zel'dovich effect is a potentially large source of systematic error for two-point function analyses, but show that it can be reduced to acceptable levels in our analysis by masking clusters of galaxies and imposing angular scale cuts on the two-point functions. The methodology developed here will be applied to the analysis of data from the DES, the SPT, and Planck in a companion work.

  15. Regional soil erosion assessment based on a sample survey and geostatistics

    Directory of Open Access Journals (Sweden)

    S. Yin

    2018-03-01

    Full Text Available Soil erosion is one of the most significant environmental problems in China. From 2010 to 2012, the fourth national census for soil erosion sampled 32 364 PSUs (Primary Sampling Units, small watersheds with the areas of 0.2–3 km2. Land use and soil erosion controlling factors including rainfall erosivity, soil erodibility, slope length, slope steepness, biological practice, engineering practice, and tillage practice for the PSUs were surveyed, and the soil loss rate for each land use in the PSUs was estimated using an empirical model, the Chinese Soil Loss Equation (CSLE. Though the information collected from the sample units can be aggregated to estimate soil erosion conditions on a large scale; the problem of estimating soil erosion condition on a regional scale has not been addressed well. The aim of this study is to introduce a new model-based regional soil erosion assessment method combining a sample survey and geostatistics. We compared seven spatial interpolation models based on the bivariate penalized spline over triangulation (BPST method to generate a regional soil erosion assessment from the PSUs. Shaanxi Province (3116 PSUs in China was selected for the comparison and assessment as it is one of the areas with the most serious erosion problem. Ten-fold cross-validation based on the PSU data showed the model assisted by the land use, rainfall erosivity factor (R, soil erodibility factor (K, slope steepness factor (S, and slope length factor (L derived from a 1 : 10 000 topography map is the best one, with the model efficiency coefficient (ME being 0.75 and the MSE being 55.8 % of that for the model assisted by the land use alone. Among four erosion factors as the covariates, the S factor contributed the most information, followed by K and L factors, and R factor made almost no contribution to the spatial estimation of soil loss. The LS factor derived from 30 or 90 m Shuttle Radar Topography Mission

  16. Choir of believers? Longitudinal evidence on public service motivation and survey participation

    DEFF Research Database (Denmark)

    Jacobsen, Christian Bøtcher; De Lorent Gad, Mette; Kjeldsen, Anne Mette

    The most widely used method to study individuals’ public service motivation is surveys. The validity and inferential power of such studies may, however, be harmed by survey participation bias, if highly public service motivated individuals are overrepresented among respondents. This paper examines...... the methodological critique of survey participation bias raised against the public service motivation literature and examines whether public service motivation increases the propensity to respond to surveys. By tracking more than 3,000 public service providers’ participation in a three-wave panel survey, our...... analysis shows that public service motivation does have a positive effect on survey participation. This suggests that future studies should pay attention to the characteristics of respondents/non-respondents and consider weighting the sample....

  17. Prevalence of dementia-associated disability among Chinese older adults: results from a national sample survey.

    Science.gov (United States)

    Li, Ning; Zhang, Lei; Du, Wei; Pang, Lihua; Guo, Chao; Chen, Gong; Zheng, Xiaoying

    2015-03-01

    Due to rapid population aging and a tidal wave of dementia, dementia has become an urgent public health issue in China. Few large-scale surveys on dementia have been conducted in China and little was known about the magnitude of dysfunction and disability caused by dementia. In this study, using national sample survey data, we aimed to describe the prevalence rate of dementia-associated disability, its associated factors, and daily activities and social functions of people with dementia-associated disability in Chinese older adults. We used the second China National Sample Survey on Disability, comprising 2,526,145 persons from 771,797 households. Identification for dementia was based on consensus manuals. Standard weighting procedures were used to construct sample weights considering the multistage stratified cluster sampling survey scheme. Population weighted numbers, weighted prevalence, and the odd ratios (ORs) were calculated. The prevalence rate of dementia-associated disability was 4.64% (95% CI: 4.26-5.01) and it accounted for 41.03% of mental disability among Chinese older adults. Urban residence (OR: 1.33 [1.12-1.57]), older age (80+ years) (OR: 4.12 [3.38-.03]), illiteracy (OR: 1.79 [1.27-2.53]), and currently not married (OR: 1.15 [1.00-1.32]) were associated with increased risk of dementia-associated disability. Compared with those with mental disability of other causes and those with other types of disabilities, older adults with dementia-asscoiated disability were more likely to have severe or extreme difficulty in daily activities and social functions. Countermeasures are warranted to obtain a more precise overview of dementia in China, and strategies on enhancing early identification, treatment, and rehabilitation should be developed for people with dementia. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  18. Sample Preparation Methodologies for In Situ Liquid and Gaseous Cell Analytical Transmission Electron Microscopy of Electropolished Specimens.

    Science.gov (United States)

    Zhong, Xiang Li; Schilling, Sibylle; Zaluzec, Nestor J; Burke, M Grace

    2016-12-01

    In recent years, an increasing number of studies utilizing in situ liquid and/or gaseous cell scanning/transmission electron microscopy (S/TEM) have been reported. Because of the difficulty in the preparation of suitable specimens, these environmental S/TEM studies have been generally limited to studies of nanoscale structured materials such as nanoparticles, nanowires, or sputtered thin films. In this paper, we present two methodologies which have been developed to facilitate the preparation of electron-transparent samples from conventional bulk metals and alloys for in situ liquid/gaseous cell S/TEM experiments. These methods take advantage of combining sequential electrochemical jet polishing followed by focused ion beam extraction techniques to create large electron-transparent areas for site-specific observation. As an example, we illustrate the application of this methodology for the preparation of in situ specimens from a cold-rolled Type 304 austenitic stainless steel sample, which was subsequently examined in both 1 atm of air as well as fully immersed in a H2O environment in the S/TEM followed by hyperspectral imaging. These preparation techniques can be successfully applied as a general procedure for a wide range of metals and alloys, and are suitable for a variety of in situ analytical S/TEM studies in both aqueous and gaseous environments.

  19. Global review of health care surveys using lot quality assurance sampling (LQAS), 1984-2004.

    Science.gov (United States)

    Robertson, Susan E; Valadez, Joseph J

    2006-09-01

    We conducted a global review on the use of lot quality assurance sampling (LQAS) to assess health care services, health behaviors, and disease burden. Publications and reports on LQAS surveys were sought from Medline and five other electronic databases; the World Health Organization; the World Bank; governments, nongovernmental organizations, and individual scientists. We identified a total of 805 LQAS surveys conducted by different management groups during January 1984 through December 2004. There was a striking increase in the annual number of LQAS surveys conducted in 2000-2004 (128/year) compared with 1984-1999 (10/year). Surveys were conducted in 55 countries, and in 12 of these countries there were 10 or more LQAS surveys. Geographically, 317 surveys (39.4%) were conducted in Africa, 197 (28.5%) in the Americas, 115 (14.3%) in the Eastern Mediterranean, 114 (14.2%) in South-East Asia, 48 (6.0%) in Europe, and 14 (1.8%) in the Western Pacific. Health care parameters varied, and some surveys assessed more than one parameter. There were 320 surveys about risk factors for HIV/AIDS/sexually transmitted infections; 266 surveys on immunization coverage, 240 surveys post-disasters, 224 surveys on women's health, 142 surveys on growth and nutrition, 136 surveys on diarrheal disease control, and 88 surveys on quality management. LQAS surveys to assess disease burden included 23 neonatal tetanus mortality surveys and 12 surveys on other diseases. LQAS is a practical field method which increasingly is being applied in assessment of preventive and curative health services, and may offer new research opportunities to social scientists. When LQAS data are collected recurrently at multiple time points, they can be used to measure the spatial variation in behavior change. Such data provide insight into understanding relationships between various investments in social, human, and physical capital, and into the effectiveness of different public health strategies in achieving

  20. Design and methodology of a mixed methods follow-up study to the 2014 Ghana Demographic and Health Survey.

    Science.gov (United States)

    Staveteig, Sarah; Aryeetey, Richmond; Anie-Ansah, Michael; Ahiadeke, Clement; Ortiz, Ladys

    2017-01-01

    The intended meaning behind responses to standard questions posed in large-scale health surveys are not always well understood. Systematic follow-up studies, particularly those which pose a few repeated questions followed by open-ended discussions, are well positioned to gauge stability and consistency of data and to shed light on the intended meaning behind survey responses. Such follow-up studies require extensive coordination and face challenges in protecting respondent confidentiality during the process of recontacting and reinterviewing participants. We describe practical field strategies for undertaking a mixed methods follow-up study during a large-scale health survey. The study was designed as a mixed methods follow-up study embedded within the 2014 Ghana Demographic and Health Survey (GDHS). The study was implemented in 13 clusters. Android tablets were used to import reference data from the parent survey and to administer the questionnaire, which asked a mixture of closed- and open-ended questions on reproductive intentions, decision-making, and family planning. Despite a number of obstacles related to recontacting respondents and concern about respondent fatigue, over 92 percent of the selected sub-sample were successfully recontacted and reinterviewed; all consented to audio recording. A confidential linkage between GDHS data, follow-up tablet data, and audio transcripts was successfully created for the purpose of analysis. We summarize the challenges in follow-up study design, including ethical considerations, sample size, auditing, filtering, successful use of tablets, and share lessons learned for future such follow-up surveys.

  1. Effects of sample survey design on the accuracy of classification tree models in species distribution models

    Science.gov (United States)

    Thomas C. Edwards; D. Richard Cutler; Niklaus E. Zimmermann; Linda Geiser; Gretchen G. Moisen

    2006-01-01

    We evaluated the effects of probabilistic (hereafter DESIGN) and non-probabilistic (PURPOSIVE) sample surveys on resultant classification tree models for predicting the presence of four lichen species in the Pacific Northwest, USA. Models derived from both survey forms were assessed using an independent data set (EVALUATION). Measures of accuracy as gauged by...

  2. Off-road sampling reveals a different grassland bird community than roadside sampling: implications for survey design and estimates to guide conservation

    Directory of Open Access Journals (Sweden)

    Troy I. Wellicome

    2014-06-01

    concern. Our results highlight the need to develop appropriate corrections for bias in estimates derived from roadside sampling, and the need to design surveys that sample bird communities across a more representative cross-section of the landscape, both near and far from roads.

  3. What about N? A methodological study of sample-size reporting in focus group studies.

    Science.gov (United States)

    Carlsen, Benedicte; Glenton, Claire

    2011-03-11

    Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out. We searched PubMed for studies that had used focus groups and that had been published in open access journals during 2008, and extracted data on the number of focus groups and on any explanation authors gave for this number. We also did a qualitative assessment of the papers with regard to how number of groups was explained and discussed. We identified 220 papers published in 117 journals. In these papers insufficient reporting of sample sizes was common. The number of focus groups conducted varied greatly (mean 8.4, median 5, range 1 to 96). Thirty seven (17%) studies attempted to explain the number of groups. Six studies referred to rules of thumb in the literature, three stated that they were unable to organize more groups for practical reasons, while 28 studies stated that they had reached a point of saturation. Among those stating that they had reached a point of saturation, several appeared not to have followed principles from grounded theory where data collection and analysis is an iterative process until saturation is reached. Studies with high numbers of focus groups did not offer explanations for number of groups. Too much data as a study weakness was not an issue discussed in any of the reviewed papers. Based on these findings we suggest that journals adopt more stringent requirements for focus group method reporting. The often poor and inconsistent reporting seen in these

  4. What about N? A methodological study of sample-size reporting in focus group studies

    Directory of Open Access Journals (Sweden)

    Glenton Claire

    2011-03-01

    Full Text Available Abstract Background Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out. Methods We searched PubMed for studies that had used focus groups and that had been published in open access journals during 2008, and extracted data on the number of focus groups and on any explanation authors gave for this number. We also did a qualitative assessment of the papers with regard to how number of groups was explained and discussed. Results We identified 220 papers published in 117 journals. In these papers insufficient reporting of sample sizes was common. The number of focus groups conducted varied greatly (mean 8.4, median 5, range 1 to 96. Thirty seven (17% studies attempted to explain the number of groups. Six studies referred to rules of thumb in the literature, three stated that they were unable to organize more groups for practical reasons, while 28 studies stated that they had reached a point of saturation. Among those stating that they had reached a point of saturation, several appeared not to have followed principles from grounded theory where data collection and analysis is an iterative process until saturation is reached. Studies with high numbers of focus groups did not offer explanations for number of groups. Too much data as a study weakness was not an issue discussed in any of the reviewed papers. Conclusions Based on these findings we suggest that journals adopt more stringent requirements for focus group method

  5. Alcohol Brand Preferences of Underage Youth: Results from a Pilot Survey among a National Sample

    Science.gov (United States)

    Siegel, Michael; DeJong, William; Naimi, Timothy S.; Heeren, Timothy; Rosenbloom, David L.; Ross, Craig; Ostroff, Joshua; Jernigan, David H.

    2011-01-01

    This study is the first investigation to explore the alcohol brand preferences of underage youth via a national survey. We conducted a pilot study of a new, internet-based alcohol brand survey with 108 youth ages 16–20 years who were recruited from an existing panel and had consumed alcohol in the past month. We ascertained respondents’ consumption of each of 380 alcohol brands during the past 30 days, including which brands of alcohol were consumed during heavy drinking episodes. Our findings suggest that, despite the wide variety of alcohol brands consumed by older adolescents in this study, alcohol preferences are concentrated among a relatively small number of brands. Accurate measurements of alcohol brand preferences will enable important new research into the factors that influence youth drinking behavior. This study establishes the feasibility and validity of a new methodology to determine patterns of brand-specific alcohol consumption among underage drinkers. PMID:22014249

  6. Use of FTA® card methodology for sampling and molecular characterization of Echinococcus granulosus sensu lato in Africa.

    Science.gov (United States)

    Boué, Franck; El Berbri, Ikhlass; Hormaz, Vanessa; Boucher, Jean-Marc; El Mamy, Ahmed Bezeid; Traore, Abdallah; Fihri, Ouafaa Fassi; Petavy, Anne-Françoise; Dakkak, Allal; Umhang, Gérald

    2017-02-01

    Cystic Echinococcosis is a parasitic disease caused by the cestode Echinococcus granulosus widely distributed in Africa. Monitoring of this parasite requires access to cyst samples on intermediate hosts observed at the slaughterhouse. In order to facilitate sampling in the field and analysis, the French National Reference Laboratory for Echinococcus spp. has developed a tissue derived from DNA sampling with FTA ® card technology. The DNA samples were taken by applying the FTA ® paper on the germinal layer after opening the cysts. The sampling technique was validated using frozen cysts (n = 76) stored in the laboratory and from field samples (n = 134) taken at the slaughterhouse by veterinarian technicians during meat inspection in Morocco, Mali and Mauritania. DNA was extracted after several weeks of storage at room temperature. PCR assays were performed using primers for generic cestode (cox1) and amplified fragments were sequenced. All samples taken in the lab and 80% of field samples were capable of molecular characterization. Cyst-derived DNA from FTA ® samples can be useful for easy sampling, storage and rapid, safe and cheap shipment. The use of the FTA methodology will facilitate studies in the field to investigate the presence and genetic characterization of E. granulosus sensu lato in African countries. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. FACE Analysis as a Fast and Reliable Methodology to Monitor the Sulfation and Total Amount of Chondroitin Sulfate in Biological Samples of Clinical Importance

    Directory of Open Access Journals (Sweden)

    Evgenia Karousou

    2014-06-01

    Full Text Available Glycosaminoglycans (GAGs due to their hydrophilic character and high anionic charge densities play important roles in various (pathophysiological processes. The identification and quantification of GAGs in biological samples and tissues could be useful prognostic and diagnostic tools in pathological conditions. Despite the noteworthy progress in the development of sensitive and accurate methodologies for the determination of GAGs, there is a significant lack in methodologies regarding sample preparation and reliable fast analysis methods enabling the simultaneous analysis of several biological samples. In this report, developed protocols for the isolation of GAGs in biological samples were applied to analyze various sulfated chondroitin sulfate- and hyaluronan-derived disaccharides using fluorophore-assisted carbohydrate electrophoresis (FACE. Applications to biologic samples of clinical importance include blood serum, lens capsule tissue and urine. The sample preparation protocol followed by FACE analysis allows quantification with an optimal linearity over the concentration range 1.0–220.0 µg/mL, affording a limit of quantitation of 50 ng of disaccharides. Validation of FACE results was performed by capillary electrophoresis and high performance liquid chromatography techniques.

  8. Using mark-recapture distance sampling methods on line transect surveys

    Science.gov (United States)

    Burt, Louise M.; Borchers, David L.; Jenkins, Kurt J.; Marques, Tigao A

    2014-01-01

    Mark–recapture distance sampling (MRDS) methods are widely used for density and abundance estimation when the conventional DS assumption of certain detection at distance zero fails, as they allow detection at distance zero to be estimated and incorporated into the overall probability of detection to better estimate density and abundance. However, incorporating MR data in DS models raises survey and analysis issues not present in conventional DS. Conversely, incorporating DS assumptions in MR models raises issues not present in conventional MR. As a result, being familiar with either conventional DS methods or conventional MR methods does not on its own put practitioners in good a position to apply MRDS methods appropriately. This study explains the sometimes subtly different varieties of MRDS survey methods and the associated concepts underlying MRDS models. This is done as far as possible without giving mathematical details – in the hope that this will make the key concepts underlying the methods accessible to a wider audience than if we were to present the concepts via equations.

  9. Nationwide survey of policies and practices related to capillary blood sampling in medical laboratories in Croatia.

    Science.gov (United States)

    Krleza, Jasna Lenicek

    2014-01-01

    Capillary sampling is increasingly used to obtain blood for laboratory tests in volumes as small as necessary and as non-invasively as possible. Whether capillary blood sampling is also frequent in Croatia, and whether it is performed according to international laboratory standards is unclear. All medical laboratories that participate in the Croatian National External Quality Assessment Program (N = 204) were surveyed on-line to collect information about the laboratory's parent institution, patient population, types and frequencies of laboratory tests based on capillary blood samples, choice of reference intervals, and policies and procedures specifically related to capillary sampling. Sampling practices were compared with guidelines from the Clinical and Laboratory Standards Institute (CLSI) and the World Health Organization (WHO). Of the 204 laboratories surveyed, 174 (85%) responded with complete questionnaires. Among the 174 respondents, 155 (89%) reported that they routinely perform capillary sampling, which is carried out by laboratory staff in 118 laboratories (76%). Nearly half of respondent laboratories (48%) do not have a written protocol including order of draw for multiple sampling. A single puncture site is used to provide capillary blood for up to two samples at 43% of laboratories that occasionally or regularly perform such sampling. Most respondents (88%) never perform arterialisation prior to capillary blood sampling. Capillary blood sampling is highly prevalent in Croatia across different types of clinical facilities and patient populations. Capillary sampling procedures are not standardised in the country, and the rate of laboratory compliance with CLSI and WHO guidelines is low.

  10. Longitudinal Emergency Medical Technician Attributes and Demographic Study (LEADS) Design and Methodology.

    Science.gov (United States)

    Levine, Roger

    2016-12-01

    The objective of this study is to describe the Longitudinal Emergency Medical Technician (EMT) Attributes and Demographic Study (LEADS) design, instrument development, pilot testing, sampling procedures, and data collection methodology. Response rates are provided, along with results of follow-up surveys of non-responders (NRs) and a special survey of Emergency Medical Services (EMS) professionals who were not nationally certified. Annual surveys from 1999 to 2008 were mailed out to a random, stratified sample of nationally registered EMT-Basics and Paramedics. Survey weights were developed to reflect each respondent's probability of selection. A special survey of NRs was mailed out to individuals who did not respond to the annual survey to estimate the probable extent and direction of response bias. Individuals who indicated they were no longer in the profession were mailed a special exit survey to determine their reasons for leaving EMS. Given the large number of comparisons between NR and regular (annual) survey respondents, it is not surprising that some statistically significant differences were found. In general, there were few differences. However, NRs tended to report higher annual EMS incomes, were younger, healthier, more physically fit, and were more likely to report that they were not practicing EMS. Comparisons of the nationally certified EMS professionals with EMS professionals who were not nationally certified indicated that nationally certified EMS providers were younger, had less EMS experiences, earned less, were more likely to be female and work for private EMS services, and less likely to work for fire-based services. These differences may reflect state and local policy and practice, since many states and local agencies do not require maintenance of national certification as a requirement to practice. When these differences were controlled for statistically, there were few systematic differences between non-nationally certified and nationally

  11. The Italian national survey on radon indoors run by several different regional laboratories: Sampling strategy, realization and follow-up

    International Nuclear Information System (INIS)

    Bochicchio, F.; Risica, S.; Piermattei, S.

    1993-01-01

    The paper outlines the criteria and organization adopted by the Italian National Institutions in carrying out a representative national survey to evaluate the distribution of radon concentration and the exposure of the Italian population to natural radiation indoors. The main items of the survey - i.e. sampling design, choice of the sample size (5000 dwellings), organization, analysis of the actual sample structure, questionnaire to collect data about families and their dwellings, experimental set up and communication with the public - are discussed. Some results, concerning a first fraction of the total sample, are also presented. (author). 13 refs, 2 figs, 2 tabs

  12. Development of the methodology of sample preparation to X-ray diffractometry of clay minerals at Petrobras Research Center

    International Nuclear Information System (INIS)

    Alves, D.B.

    1987-01-01

    Various procedures can be used in the analysis of the clay mineral content of rocks by X-ray diffraction. This article describes the principal ones and discusses those adopted in the X-ray clay mineral laboratory of the PETROBRAS Research Center (CENPES) in Rio de Janeiro. This article presents the methodology used and provides users with information about its application and limitations. The methodology has been developed to study polymineral samples. The aim to identify clay mineral groups and to estimate their relative proportions. Of the four main steps of this analysis - separation and concentration of clay minerals, preparation of oriented specimens, X-ray irradiation under standard conditions and interpretation of X-ray diffraction patterns - only the first three are discussed here. Clay minerals occur mainly in the [pt

  13. EFL Teaching Methodological Practices in Cali

    Directory of Open Access Journals (Sweden)

    Chaves Orlando

    2013-04-01

    Full Text Available In this article we aim at showing partial results of a study about the profiles of English as a Foreign Language (EFL teachers in both public and private primary and secondary strata 1-4 schools in Cali, Colombia. Teachers’ methodological approaches and practices are described and analyzed from a sample of 220 teachers. Information was gathered from surveys, interviews and institutional documents. The quantitative information was processed with the Statistical Package for the Social Sciences and Excelwhile the qualitative information (from a survey and focal interviews was analyzed hermeneutically. An analysis grid was used for the examination of institutional documents (area planning, syllabi, and didactic materials. Teachers’ methodology (approaches/methods, lessons, activities, objectives, curricula, syllabi and evaluation are analyzed in the light of literature in the field. Finally, we discuss theimplications of methodological approaches.En este artículo se presentan los resultados parciales de una investigación sobre los perfiles de los profesores de inglés como lengua extranjera que enseñan en colegios de educación básica primaria y secundaria, públicos y privados, de estratos 1 a 4 en Cali, Colombia. Se describen y analizan sus enfoques y prácticas metodológicas a partir de una muestra de 220 docentes. Se obtuvo información cualitativa y cuantitativa por medio de encuestas, entrevistas y documentos institucionales. La información cuantitativa se procesó con el software Statistical Package for Social Sciences y Excel, mientras que la información cualitativa se analizó hermenéuticamente. Se usó una rejilla de análisispara el examen de los documentos institucionales (planes de área, programas, y materiales didácticos. La metodología (enfoques/métodos, clases, actividades, objetivos, currículo, programas y evaluación se analizan a partir de la literatura especializada en el campo. Finalmente, se

  14. Socially responsible ethnobotanical surveys in the Cape Floristic Region: ethical principles, methodology and quantification of data

    Directory of Open Access Journals (Sweden)

    Ben-Erik Van Wyk

    2012-03-01

    Full Text Available A broad overview of published and unpublished ethnobotanical surveys in the Cape Floristic Region (the traditional home of the San and Khoi communities shows that the data is incomplete. There is an urgent need to record the rich indigenous knowledge about plants in a systematic and social responsible manner in order to preserve this cultural and scientific heritage for future generations. Improved methods for quantifying data are introduced, with special reference to the simplicity and benefits of the new Matrix Method. This methodology prevents or reduces the number of false negatives, and also ensures the participation of elderly people who might be immobile. It also makes it possible to compare plant uses in different local communities. This method enables the researcher to quantify the knowledge on plant use that was preserved in a community, and to determine the relative importance of a specific plant in a more objective way. Ethical considerations for such ethnobotanical surveys are discussed, through the lens of current ethical codes and international conventions. This is an accessible approach, which can also be used in the life sciences classroom.

  15. Analysis and radiological assessment of survey results and samples from the beaches around Sellafield

    International Nuclear Information System (INIS)

    Webb, G.A.M.; Fry, F.A.

    1983-12-01

    After radioactive sea debris had been found on beaches near the BNFL, Sellafield, plant, NRPB was asked by the Department of the Environment to analyse some of the samples collected and to assess the radiological hazard to members of the public. A report is presented containing an analysis of survey reports for the period 19 November - 4 December 1983 and preliminary results of the analysis of all samples received, together with the Board's recommendations. (author)

  16. USGS Methodology for Assessing Continuous Petroleum Resources

    Science.gov (United States)

    Charpentier, Ronald R.; Cook, Troy A.

    2011-01-01

    The U.S. Geological Survey (USGS) has developed a new quantitative methodology for assessing resources in continuous (unconventional) petroleum deposits. Continuous petroleum resources include shale gas, coalbed gas, and other oil and gas deposits in low-permeability ("tight") reservoirs. The methodology is based on an approach combining geologic understanding with well productivities. The methodology is probabilistic, with both input and output variables as probability distributions, and uses Monte Carlo simulation to calculate the estimates. The new methodology is an improvement of previous USGS methodologies in that it better accommodates the uncertainties in undrilled or minimally drilled deposits that must be assessed using analogs. The publication is a collection of PowerPoint slides with accompanying comments.

  17. Trypanosoma brucei gambiense trypanosomiasis in Terego county, northern Uganda, 1996: a lot quality assurance sampling survey.

    Science.gov (United States)

    Hutin, Yvan J F; Legros, Dominique; Owini, Vincent; Brown, Vincent; Lee, Evan; Mbulamberi, Dawson; Paquet, Christophe

    2004-04-01

    We estimated the pre-intervention prevalence of Trypanosoma brucei gambiense (Tbg) trypanosomiasis using the lot quality assurance sampling (LQAS) methods in 14 parishes of Terego County in northern Uganda. A total of 826 participants were included in the survey sample in 1996. The prevalence of laboratory confirmed Tbg trypanosomiasis adjusted for parish population sizes was 2.2% (95% confidence interval =1.1-3.2). This estimate was consistent with the 1.1% period prevalence calculated on the basis of cases identified through passive and active screening in 1996-1999. Ranking of parishes in four categories according to LQAS analysis of the 1996 survey predicted the prevalences observed during the first round of active screening in the population in 1997-1998 (P LQAS were validated by the results of the population screening, suggesting that these survey methods may be useful in the pre-intervention phase of sleeping sickness control programs.

  18. The Health Behaviour in School-aged Children (HBSC) study: methodological developments and current tensions

    DEFF Research Database (Denmark)

    Roberts, Chris; Freeman, John; Samdal, Oddrun

    2009-01-01

    OBJECTIVES: To describe the methodological development of the HBSC survey since its inception and explore methodological tensions that need to be addressed in the ongoing work on this and other large-scale cross-national surveys. METHODS: Using archival data and conversations with members...... of the network, we collaboratively analysed our joint understandings of the survey's methodology. RESULTS: We identified four tensions that are likely to be present in upcoming survey cycles: (1) maintaining quality standards against a background of rapid growth, (2) continuous improvement with limited financial...... in working through such challenges renders it likely that HBSC can provide a model of other similar studies facing these tensions....

  19. Determination of radium isotopes in environmental samples by gamma spectrometry, liquid scintillation counting and alpha spectrometry: a review of analytical methodology

    International Nuclear Information System (INIS)

    Jia, Guogang; Jia, Jing

    2012-01-01

    Radium (Ra) isotopes are important from the viewpoints of radiation protection and environmental protection. Their high toxicity has stimulated the continuing interest in methodology research for determination of Ra isotopes in various media. In this paper, the three most routinely used analytical techniques for Ra isotope determination in biological and environmental samples, i.e. low-background γ-spectrometry, liquid scintillation counting and α-spectrometry, were reviewed, with emphasis on new methodological developments in sample preparation, preconcentration, separation, purification, source preparation and measurement techniques. The accuracy, selectivity, traceability, applicability and minimum detectable activity (MDA) of the three techniques were discussed. It was concluded that the MDA (0.1 mBq L −1 ) of the α-spectrometry technique coupled with chemical separation is about two orders of magnitude lower than that of low-background HPGe γ-spectrometry and LSC techniques. Therefore, when maximum sensitivity is required, the α-spectrometry technique remains the first choice. - Highlights: ► A review is made for determination of Ra isotopes in environmental samples. ► Gamma spectrometry, LSC and a-spectrometry are the main concerned radiometric approach. ► Sample preparation, preconcentration, separation and source preparation are discussed. ► The methods can analyse air, water, seawater, soil, sediment and foodstuffs samples. ► Some new data obtained recently from our laboratory for Ra method study are included.

  20. Biased sampling, over-identified parameter problems and beyond

    CERN Document Server

    Qin, Jing

    2017-01-01

    This book is devoted to biased sampling problems (also called choice-based sampling in Econometrics parlance) and over-identified parameter estimation problems. Biased sampling problems appear in many areas of research, including Medicine, Epidemiology and Public Health, the Social Sciences and Economics. The book addresses a range of important topics, including case and control studies, causal inference, missing data problems, meta-analysis, renewal process and length biased sampling problems, capture and recapture problems, case cohort studies, exponential tilting genetic mixture models etc. The goal of this book is to make it easier for Ph. D students and new researchers to get started in this research area. It will be of interest to all those who work in the health, biological, social and physical sciences, as well as those who are interested in survey methodology and other areas of statistical science, among others. .

  1. The Swift Gamma-Ray Burst Host Galaxy Legacy Survey. I. Sample Selection and Redshift Distribution

    Science.gov (United States)

    Perley, D. A.; Kruhler, T.; Schulze, S.; Postigo, A. De Ugarte; Hjorth, J.; Berger, E.; Cenko, S. B.; Chary, R.; Cucchiara, A.; Ellis, R.; hide

    2016-01-01

    We introduce the Swift Gamma-Ray Burst Host Galaxy Legacy Survey (SHOALS), a multi-observatory high redshift galaxy survey targeting the largest unbiased sample of long-duration gamma-ray burst (GRB) hosts yet assembled (119 in total). We describe the motivations of the survey and the development of our selection criteria, including an assessment of the impact of various observability metrics on the success rate of afterglow-based redshift measurement. We briefly outline our host galaxy observational program, consisting of deep Spitzer/IRAC imaging of every field supplemented by similarly deep, multicolor optical/near-IR photometry, plus spectroscopy of events without preexisting redshifts. Our optimized selection cuts combined with host galaxy follow-up have so far enabled redshift measurements for 110 targets (92%) and placed upper limits on all but one of the remainder. About 20% of GRBs in the sample are heavily dust obscured, and at most 2% originate from z > 5.5. Using this sample, we estimate the redshift-dependent GRB rate density, showing it to peak at z approx. 2.5 and fall by at least an order of magnitude toward low (z = 0) redshift, while declining more gradually toward high (z approx. 7) redshift. This behavior is consistent with a progenitor whose formation efficiency varies modestly over cosmic history. Our survey will permit the most detailed examination to date of the connection between the GRB host population and general star-forming galaxies, directly measure evolution in the host population over cosmic time and discern its causes, and provide new constraints on the fraction of cosmic star formation occurring in undetectable galaxies at all redshifts.

  2. Comparing econometric and survey-based methodologies in measuring offshoring

    DEFF Research Database (Denmark)

    Refslund, Bjarke

    2016-01-01

    such as the national or regional level. Most macro analyses are based on proxies and trade statistics with limitations. Drawing on unique Danish survey data, this article demonstrates how survey data can provide important insights into the national scale and impacts of offshoring, including changes of employment...

  3. Comparing two survey methods of measuring health-related indicators: Lot Quality Assurance Sampling and Demographic Health Surveys.

    Science.gov (United States)

    Anoke, Sarah C; Mwai, Paul; Jeffery, Caroline; Valadez, Joseph J; Pagano, Marcello

    2015-12-01

    Two common methods used to measure indicators for health programme monitoring and evaluation are the demographic and health surveys (DHS) and lot quality assurance sampling (LQAS); each one has different strengths. We report on both methods when utilised in comparable situations. We compared 24 indicators in south-west Uganda, where data for prevalence estimations were collected independently for the two methods in 2011 (LQAS: n = 8876; DHS: n = 1200). Data were stratified (e.g. gender and age) resulting in 37 comparisons. We used a two-sample two-sided Z-test of proportions to compare both methods. The average difference between LQAS and DHS for 37 estimates was 0.062 (SD = 0.093; median = 0.039). The average difference among the 21 failures to reject equality of proportions was 0.010 (SD = 0.041; median = 0.009); among the 16 rejections, it was 0.130 (SD = 0.010, median = 0.118). Seven of the 16 rejections exhibited absolute differences of 0.10 and 0.20 (mean = 0.261, SD = 0.083). There is 75.7% agreement across the two surveys. Both methods yield regional results, but only LQAS provides information at less granular levels (e.g. the district level) where managerial action is taken. The cost advantage and localisation make LQAS feasible to conduct more frequently, and provides the possibility for real-time health outcomes monitoring. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

  4. Improved USGS methodology for assessing continuous petroleum resources

    Science.gov (United States)

    Charpentier, Ronald R.; Cook, Troy A.

    2010-01-01

    This report presents an improved methodology for estimating volumes of continuous (unconventional) oil and gas resources within the United States and around the world. The methodology is based on previously developed U.S. Geological Survey methodologies that rely on well-scale production data. Improvements were made primarily to how the uncertainty about estimated ultimate recoveries is incorporated in the estimates. This is particularly important when assessing areas with sparse or no production data, because the new methodology allows better use of analog data from areas with significant discovery histories.

  5. Didactic content and teaching methodologies on required allopathic US family medicine clerkships.

    Science.gov (United States)

    Schwiebert, L P; Aspy, C B

    1999-02-01

    Despite the increased prominence of family medicine clerkships in required third- and fourth-year clinical rotations in US allopathic medical schools, the content of these clerkships varies markedly among institutions, and there is little in the literature concerning the current or desired content of family medicine clerkships. This study explores the didactic content of a national sample of required family medicine clerkships to assess what and how this important aspect of clerkship curriculum is taught. Using an original survey instrument, we surveyed US medical schools through mailings and follow-up phone contacts. We categorized free-form responses using a coding dictionary specific to this study and computed descriptive statistics. Of 127 medical schools contacted, 105 (83%) responded. Among respondents, 86 (82%) had a required family medicine clerkship, 80% of them in the third year. Mean clerkship length was 5.3 weeks (median = 4 weeks), and the mean number of didactic sessions was about 2 per week. Almost 80% of clerkships had sessions in the broad area of family medicine, and prevention was the most frequent individual topic, taught in 32 (37%) of clerkships. Seventy-one percent of sessions used methodologies other than lectures. The mean time devoted to teaching 24 of the top 26 topics identified in the survey was between 1.2 and 3.1 hours/rotation, although case presentations and common problems each averaged more than 7 hours on clerkships teaching these topics. This survey provided more detailed information than previously available about the didactic content of required US allopathic family medicine clerkships. The survey also documented the lack of agreement among these clerkships on didactic content. Most didactic sessions used interactive rather than lecture format. The information from this first detailed survey provides family medicine clerkship directors with national comparisons of didactic content and methodology as a foundation for further

  6. SED fitting with MCMC: methodology and application to large galaxy surveys

    Science.gov (United States)

    Acquaviva, Viviana; Gawiser, Eric; Guaita, Lucia

    2012-08-01

    We present GalMC (Acquaviva et al. 2011), our publicly available Markov Chain Monte Carlo algorithm for SED fitting, show the results obtained for a stacked sample of Lyman Alpha Emitting galaxies at z ~ 3, and discuss the dependence of the inferred SED parameters on the assumptions made in modeling the stellar populations. We also introduce SpeedyMC, a version of GalMC based on interpolation of pre-computed template libraries. While the flexibility and number of SED fitting parameters is reduced with respect to GalMC, the average running time decreases by a factor of 20,000, enabling SED fitting of each galaxy in about one second on a 2.2GHz MacBook Pro laptop, and making SpeedyMC the ideal instrument to analyze data from large photometric galaxy surveys.

  7. Nationwide survey of policies and practices related to capillary blood sampling in medical laboratories in Croatia

    Science.gov (United States)

    Krleza, Jasna Lenicek

    2014-01-01

    Introduction: Capillary sampling is increasingly used to obtain blood for laboratory tests in volumes as small as necessary and as non-invasively as possible. Whether capillary blood sampling is also frequent in Croatia, and whether it is performed according to international laboratory standards is unclear. Materials and methods: All medical laboratories that participate in the Croatian National External Quality Assessment Program (N = 204) were surveyed on-line to collect information about the laboratory’s parent institution, patient population, types and frequencies of laboratory tests based on capillary blood samples, choice of reference intervals, and policies and procedures specifically related to capillary sampling. Sampling practices were compared with guidelines from the Clinical and Laboratory Standards Institute (CLSI) and the World Health Organization (WHO). Results: Of the 204 laboratories surveyed, 174 (85%) responded with complete questionnaires. Among the 174 respondents, 155 (89%) reported that they routinely perform capillary sampling, which is carried out by laboratory staff in 118 laboratories (76%). Nearly half of respondent laboratories (48%) do not have a written protocol including order of draw for multiple sampling. A single puncture site is used to provide capillary blood for up to two samples at 43% of laboratories that occasionally or regularly perform such sampling. Most respondents (88%) never perform arterialisation prior to capillary blood sampling. Conclusions: Capillary blood sampling is highly prevalent in Croatia across different types of clinical facilities and patient populations. Capillary sampling procedures are not standardised in the country, and the rate of laboratory compliance with CLSI and WHO guidelines is low. PMID:25351353

  8. HIV / AIDS prevalence testing - merits, methodology and outcomes ...

    African Journals Online (AJOL)

    HIV / AIDS prevalence testing - merits, methodology and outcomes of a survey conducted at a large mining organisation in South Africa. ... These baseline prevalence data also provide an opportunity for monitoring of proposed interventions using cross-sectional surveys at designated intervals in the future. South African ...

  9. Estimation of Social Exclusion Indicators from Complex Surveys: The R Package laeken

    Directory of Open Access Journals (Sweden)

    Andreas Alfons

    2013-09-01

    Full Text Available Units sampled from finite populations typically come with different inclusion proba- bilities. Together with additional preprocessing steps of the raw data, this yields unequal sampling weights of the observations. Whenever indicators are estimated from such com- plex samples, the corresponding sampling weights have to be taken into account. In addition, many indicators suffer from a strong influence of outliers, which are a common problem in real-world data. The R package laeken is an object-oriented toolkit for the estimation of indicators from complex survey samples via standard or robust methods. In particular the most widely used social exclusion and poverty indicators are imple- mented in the package. A general calibrated bootstrap method to estimate the variance of indicators for common survey designs is included as well. Furthermore, the package contains synthetically generated close-to-reality data for the European Union Statistics on Income and Living Conditions and the Structure of Earnings Survey, which are used in the code examples throughout the paper. Even though the paper is focused on showing the functionality of package laeken, it also provides a brief mathematical description of the implemented indicator methodology.

  10. Gathering Opinions on Depression Information Needs and Preferences: Samples and Opinions in Clinic Versus Web-Based Surveys.

    Science.gov (United States)

    Bernstein, Matthew T; Walker, John R; Sexton, Kathryn A; Katz, Alan; Beatie, Brooke E

    2017-04-24

    There has been limited research on the information needs and preferences of the public concerning treatment for depression. Very little research is available comparing samples and opinions when recruitment for surveys is done over the Web as opposed to a personal invitation to complete a paper survey. This study aimed to (1) to explore information needs and preferences among members of the public and (2) compare Clinic and Web samples on sample characteristics and survey findings. Web survey participants were recruited with a notice on three self-help association websites (N=280). Clinic survey participants were recruited by a research assistant in the waiting rooms of a family medicine clinic and a walk-in medical clinic (N=238) and completed a paper version of the survey. The Clinic and Web samples were similar in age (39.0 years, SD 13.9 vs 40.2 years, SD 12.5, respectively), education, and proportion in full time employment. The Clinic sample was more diverse in demographic characteristics and closer to the demographic characteristics of the region (Winnipeg, Canada) with a higher proportion of males (102/238 [42.9%] vs 45/280 [16.1%]) and nonwhites (Aboriginal, Asian, and black) (69/238 [29.0%] vs 39/280 [13.9%]). The Web sample reported a higher level of emotional distress and had more previous psychological (224/280 [80.0%] vs 83/238 [34.9%]) and pharmacological (202/280 [72.1%] vs 57/238 [23.9%]) treatment. In terms of opinions, most respondents in both settings saw information on a wide range of topics around depression treatment as very important including information about treatment choices, effectiveness of treatment, how long it takes treatment to work, how long treatment continues, what happens when treatment stops, advantages and disadvantages of treatments, and potential side effects. Females, respondents with a white background, and those who had received or felt they would have benefited from therapy in the past saw more information topics as very

  11. Survey of Transmission Cost Allocation Methodologies for Regional Transmission Organizations

    Energy Technology Data Exchange (ETDEWEB)

    Fink, S.; Porter, K.; Mudd, C.; Rogers, J.

    2011-02-01

    The report presents transmission cost allocation methodologies for reliability transmission projects, generation interconnection, and economic transmission projects for all Regional Transmission Organizations.

  12. Measuring Substance Use and Misuse via Survey Research: Unfinished Business.

    Science.gov (United States)

    Johnson, Timothy P

    2015-01-01

    This article reviews unfinished business regarding the assessment of substance use behaviors by using survey research methodologies, a practice that dates back to the earliest years of this journal's publication. Six classes of unfinished business are considered including errors of sampling, coverage, non-response, measurement, processing, and ethics. It may be that there is more now that we do not know than when this work began some 50 years ago.

  13. A Survey for Spectroscopic Binaries in a Large Sample of G Dwarfs

    Science.gov (United States)

    Udry, S.; Mayor, M.; Latham, D. W.; Stefanik, R. P.; Torres, G.; Mazeh, T.; Goldberg, D.; Andersen, J.; Nordstrom, B.

    For more than 5 years now, the radial velocities for a large sample of G dwarfs (3,347 stars) have been monitored in order to obtain an unequaled set of orbital parameters for solar-type stars (~400 orbits, up to now). This survey provides a considerable improvement on the classical systematic study by Duquennoy and Mayor (1991; DM91). The observational part of the survey has been carried out in the context of a collaboration between the Geneva Observatory on the two coravel spectrometers for the southern sky and CfA at Oakridge and Whipple Observatories for the northern sky. As a first glance at these new results, we will address in this contribution a special aspect of the orbital eccentricity distribution, namely the disappearance of the void observed in DM91 for quasi-circular orbits with periods larger than 10 days.

  14. Establishing the need for nutrition education: I. Methodology.

    Science.gov (United States)

    Vaden, A G; Newell, G K; Dayton, A D; Foley, C S

    1983-10-01

    Developmental and data collection phases for a comprehensive needs assessment project designed to provide baseline data for planning a statewide nutrition education and training project are summarized. To meet project objectives, 97 Kansas elementary schools were selected randomly as sampling units. A mail questionnaire was used to assess nutrition knowledge and attitudes and dietary and nutrition education practices of elementary teachers and food service personnel. Data from fifth grade students were collected on-site at each school. A written test was used to measure students' nutrition knowledge, attitudes, and practices. Students' nutritional status was partially assessed by measuring their height, weight, skinfold thickness, and upper arm circumference. As an additional assessment, 24-hour dietary recall interviews were conducted with a random sample of the students. In this article, each aspect of the data collection methodology is described in detail. As emphasized by authorities in the field, more complete information is needed in many nutrition survey reports to assist in useful interpretations and for comparisons among studies.

  15. THE SLOAN DIGITAL SKY SURVEY QUASAR LENS SEARCH. IV. STATISTICAL LENS SAMPLE FROM THE FIFTH DATA RELEASE

    International Nuclear Information System (INIS)

    Inada, Naohisa; Oguri, Masamune; Shin, Min-Su; Kayo, Issha; Fukugita, Masataka; Strauss, Michael A.; Gott, J. Richard; Hennawi, Joseph F.; Morokuma, Tomoki; Becker, Robert H.; Gregg, Michael D.; White, Richard L.; Kochanek, Christopher S.; Chiu, Kuenley; Johnston, David E.; Clocchiatti, Alejandro; Richards, Gordon T.; Schneider, Donald P.; Frieman, Joshua A.

    2010-01-01

    We present the second report of our systematic search for strongly lensed quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive follow-up observations of 136 candidate objects, we find 36 lenses in the full sample of 77,429 spectroscopically confirmed quasars in the SDSS Data Release 5. We then define a complete sample of 19 lenses, including 11 from our previous search in the SDSS Data Release 3, from the sample of 36,287 quasars with i Λ = 0.84 +0.06 -0.08 (stat.) +0.09 -0.07 (syst.) assuming a flat universe, which is in good agreement with other cosmological observations. We also report the discoveries of seven binary quasars with separations ranging from 1.''1 to 16.''6, which are identified in the course of our lens survey. This study concludes the construction of our statistical lens sample in the full SDSS-I data set.

  16. The PsyCoLaus study: methodology and characteristics of the sample of a population-based survey on psychiatric disorders and their association with genetic and cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Middleton Lefkos

    2009-03-01

    Full Text Available Abstract Background The Psychiatric arm of the population-based CoLaus study (PsyCoLaus is designed to: 1 establish the prevalence of threshold and subthreshold psychiatric syndromes in the 35 to 66 year-old population of the city of Lausanne (Switzerland; 2 test the validity of postulated definitions for subthreshold mood and anxiety syndromes; 3 determine the associations between psychiatric disorders, personality traits and cardiovascular diseases (CVD, 4 identify genetic variants that can modify the risk for psychiatric disorders and determine whether genetic risk factors are shared between psychiatric disorders and CVD. This paper presents the method as well as sociodemographic and somatic characteristics of the sample. Methods All 35 to 66 year-old persons previously selected for the population-based CoLaus survey on risk factors for CVD were asked to participate in a substudy assessing psychiatric conditions. This investigation included the Diagnostic Interview for Genetic Studies to elicit diagnostic criteria for threshold disorders according to DSM-IV and algorithmically defined subthreshold syndromes. Complementary information was collected on potential risk and protective factors for psychiatric disorders, migraine and on the morbidity of first-degree relatives, whereas the collection of DNA and plasma samples was already part of the original CoLaus survey. Results A total of 3,691 individuals completed the psychiatric evaluation (67% participation. The gender distribution of the sample did not differ significantly from that of the general population in the same age range. Although the youngest 5-year band of the cohort was underrepresented and the oldest 5-year band overrepresented, participants of PsyCoLaus and individuals who refused to participate revealed comparable scores on the General Health Questionnaire, a self-rating instrument completed at the somatic exam. Conclusion Despite limitations resulting from the relatively low

  17. (Per)Forming Archival Research Methodologies

    Science.gov (United States)

    Gaillet, Lynee Lewis

    2012-01-01

    This article raises multiple issues associated with archival research methodologies and methods. Based on a survey of recent scholarship and interviews with experienced archival researchers, this overview of the current status of archival research both complicates traditional conceptions of archival investigation and encourages scholars to adopt…

  18. Multidrug resistance among new tuberculosis cases: detecting local variation through lot quality-assurance sampling.

    Science.gov (United States)

    Hedt, Bethany Lynn; van Leth, Frank; Zignol, Matteo; Cobelens, Frank; van Gemert, Wayne; Nhung, Nguyen Viet; Lyepshina, Svitlana; Egwaga, Saidi; Cohen, Ted

    2012-03-01

    Current methodology for multidrug-resistant tuberculosis (MDR TB) surveys endorsed by the World Health Organization provides estimates of MDR TB prevalence among new cases at the national level. On the aggregate, local variation in the burden of MDR TB may be masked. This paper investigates the utility of applying lot quality-assurance sampling to identify geographic heterogeneity in the proportion of new cases with multidrug resistance. We simulated the performance of lot quality-assurance sampling by applying these classification-based approaches to data collected in the most recent TB drug-resistance surveys in Ukraine, Vietnam, and Tanzania. We explored 3 classification systems- two-way static, three-way static, and three-way truncated sequential sampling-at 2 sets of thresholds: low MDR TB = 2%, high MDR TB = 10%, and low MDR TB = 5%, high MDR TB = 20%. The lot quality-assurance sampling systems identified local variability in the prevalence of multidrug resistance in both high-resistance (Ukraine) and low-resistance settings (Vietnam). In Tanzania, prevalence was uniformly low, and the lot quality-assurance sampling approach did not reveal variability. The three-way classification systems provide additional information, but sample sizes may not be obtainable in some settings. New rapid drug-sensitivity testing methods may allow truncated sequential sampling designs and early stopping within static designs, producing even greater efficiency gains. Lot quality-assurance sampling study designs may offer an efficient approach for collecting critical information on local variability in the burden of multidrug-resistant TB. Before this methodology is adopted, programs must determine appropriate classification thresholds, the most useful classification system, and appropriate weighting if unbiased national estimates are also desired.

  19. Improving Training in Methodology Enriches the Science of Psychology

    Science.gov (United States)

    Aiken, Leona S.; West, Stephen G.; Millsap, Roger E.

    2009-01-01

    Replies to the comment Ramifications of increased training in quantitative methodology by Herbet Zimiles on the current authors original article "Doctoral training in statistics, measurement, and methodology in psychology: Replication and extension of Aiken, West, Sechrest, and Reno's (1990) survey of PhD programs in North America". The…

  20. Multiple sensitive estimation and optimal sample size allocation in the item sum technique.

    Science.gov (United States)

    Perri, Pier Francesco; Rueda García, María Del Mar; Cobo Rodríguez, Beatriz

    2018-01-01

    For surveys of sensitive issues in life sciences, statistical procedures can be used to reduce nonresponse and social desirability response bias. Both of these phenomena provoke nonsampling errors that are difficult to deal with and can seriously flaw the validity of the analyses. The item sum technique (IST) is a very recent indirect questioning method derived from the item count technique that seeks to procure more reliable responses on quantitative items than direct questioning while preserving respondents' anonymity. This article addresses two important questions concerning the IST: (i) its implementation when two or more sensitive variables are investigated and efficient estimates of their unknown population means are required; (ii) the determination of the optimal sample size to achieve minimum variance estimates. These aspects are of great relevance for survey practitioners engaged in sensitive research and, to the best of our knowledge, were not studied so far. In this article, theoretical results for multiple estimation and optimal allocation are obtained under a generic sampling design and then particularized to simple random sampling and stratified sampling designs. Theoretical considerations are integrated with a number of simulation studies based on data from two real surveys and conducted to ascertain the efficiency gain derived from optimal allocation in different situations. One of the surveys concerns cannabis consumption among university students. Our findings highlight some methodological advances that can be obtained in life sciences IST surveys when optimal allocation is achieved. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Assessing the quantified impact of a hybrid POGIL methodology on student averages in a forensic science survey course

    Science.gov (United States)

    Meeks, Tyna L.

    A causal-comparative/quasi experimental study examined the effect of incorporating a hybrid teaching methodology that blended lecture with Process Oriented Guided Inquiry Lessons (POGILs) on the overall academic achievement of a diverse student body in a large lecture setting. Additional considerations included student gender, ethnicity, declared major (STEM or non-STEM), and SAT scores. An evaluation of the effect that these characteristics had on student achievement due to differentiating import placed on the use of POGILs as a learning tool was included. This study used data obtained from a longitudinal examination of eight years of student data from an introductory forensic science survey course offered in a R1 northeastern university. This study addressed the effectiveness of applying a proscribed active learning methodology, one proposed effective in collegiate education, to a new environment, forensic science. The methodology employed combined fourteen POGILs, created specifically for the chosen course, with didactic lecture during the entire semester of a forensic science survey course. This quasi-experimental design used the manipulation of the independent variable, the use of a hybrid lecture instead of exclusive use of traditional didactic lectures, on the students' academic achievement on exams given during the course. Participants in this study (N=1436) were undergraduate students enrolled in the single semester introductory science course. A longitudinal study that incorporated eight years of data was completed, 4 years pre-intervention (2007-2010) and 4 years post-intervention (2011-2014). The forensic science survey course, taught by only one professor during the eight-year period, was a science discipline that had yet to integrate an active learning educational model. Findings indicate four variables significantly contributed to explaining nearly 28% of the variation seen in the student class averages earned during the eight-year period: the

  2. Optimum strata boundaries and sample sizes in health surveys using auxiliary variables.

    Science.gov (United States)

    Reddy, Karuna Garan; Khan, Mohammad G M; Khan, Sabiha

    2018-01-01

    Using convenient stratification criteria such as geographical regions or other natural conditions like age, gender, etc., is not beneficial in order to maximize the precision of the estimates of variables of interest. Thus, one has to look for an efficient stratification design to divide the whole population into homogeneous strata that achieves higher precision in the estimation. In this paper, a procedure for determining Optimum Stratum Boundaries (OSB) and Optimum Sample Sizes (OSS) for each stratum of a variable of interest in health surveys is developed. The determination of OSB and OSS based on the study variable is not feasible in practice since the study variable is not available prior to the survey. Since many variables in health surveys are generally skewed, the proposed technique considers the readily-available auxiliary variables to determine the OSB and OSS. This stratification problem is formulated into a Mathematical Programming Problem (MPP) that seeks minimization of the variance of the estimated population parameter under Neyman allocation. It is then solved for the OSB by using a dynamic programming (DP) technique. A numerical example with a real data set of a population, aiming to estimate the Haemoglobin content in women in a national Iron Deficiency Anaemia survey, is presented to illustrate the procedure developed in this paper. Upon comparisons with other methods available in literature, results reveal that the proposed approach yields a substantial gain in efficiency over the other methods. A simulation study also reveals similar results.

  3. Dark Energy Survey Year 1 Results: Multi-Probe Methodology and Simulated Likelihood Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Krause, E.; et al.

    2017-06-28

    We present the methodology for and detail the implementation of the Dark Energy Survey (DES) 3x2pt DES Year 1 (Y1) analysis, which combines configuration-space two-point statistics from three different cosmological probes: cosmic shear, galaxy-galaxy lensing, and galaxy clustering, using data from the first year of DES observations. We have developed two independent modeling pipelines and describe the code validation process. We derive expressions for analytical real-space multi-probe covariances, and describe their validation with numerical simulations. We stress-test the inference pipelines in simulated likelihood analyses that vary 6-7 cosmology parameters plus 20 nuisance parameters and precisely resemble the analysis to be presented in the DES 3x2pt analysis paper, using a variety of simulated input data vectors with varying assumptions. We find that any disagreement between pipelines leads to changes in assigned likelihood $\\Delta \\chi^2 \\le 0.045$ with respect to the statistical error of the DES Y1 data vector. We also find that angular binning and survey mask do not impact our analytic covariance at a significant level. We determine lower bounds on scales used for analysis of galaxy clustering (8 Mpc$~h^{-1}$) and galaxy-galaxy lensing (12 Mpc$~h^{-1}$) such that the impact of modeling uncertainties in the non-linear regime is well below statistical errors, and show that our analysis choices are robust against a variety of systematics. These tests demonstrate that we have a robust analysis pipeline that yields unbiased cosmological parameter inferences for the flagship 3x2pt DES Y1 analysis. We emphasize that the level of independent code development and subsequent code comparison as demonstrated in this paper is necessary to produce credible constraints from increasingly complex multi-probe analyses of current data.

  4. Men who have sex with men in Great Britain: comparing methods and estimates from probability and convenience sample surveys

    OpenAIRE

    Prah, Philip; Hickson, Ford; Bonell, Chris; McDaid, Lisa M; Johnson, Anne M; Wayal, Sonali; Clifton, Soazig; Sonnenberg, Pam; Nardone, Anthony; Erens, Bob; Copas, Andrew J; Riddell, Julie; Weatherburn, Peter; Mercer, Catherine H

    2016-01-01

    Objective: To examine sociodemographic and behavioural differences between men whohave sex with men (MSM) participating in recent UK convenience surveys and a national probability sample survey.\\ud Methods: We compared 148 MSM aged 18–64 years interviewed for Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) undertaken in 2010–2012, with men inthe same age range participating in contemporaneous convenience surveys of MSM: 15 500 British resident men in the European...

  5. Towards Standardization of Sampling Methodology for Evaluation of ...

    African Journals Online (AJOL)

    This article proposes the procedure that may be adopted for comparable, representative and cost effective, soil sampling, and thereafter explores the policy issues regarding standardization of sampling activities and analytical process as it relates to soil pollution in Nigeria. Standardized sampling and analytical data for soil ...

  6. Cross-Continental Comparison of National Food Consumption Survey Methods—A Narrative Review

    Directory of Open Access Journals (Sweden)

    Willem De Keyzer

    2015-05-01

    Full Text Available Food consumption surveys are performed in many countries. Comparison of results from those surveys across nations is difficult because of differences in methodological approaches. While consensus about the preferred methodology associated with national food consumption surveys is increasing, no inventory of methodological aspects across continents is available. The aims of the present review are (1 to develop a framework of key methodological elements related to national food consumption surveys, (2 to create an inventory of these properties of surveys performed in the continents North-America, South-America, Asia and Australasia, and (3 to discuss and compare these methodological properties cross-continentally. A literature search was performed using a fixed set of search terms in different databases. The inventory was completed with all accessible information from all retrieved publications and corresponding authors were requested to provide additional information where missing. Surveys from ten individual countries, originating from four continents are listed in the inventory. The results are presented according to six major aspects of food consumption surveys. The most common dietary intake assessment method used in food consumption surveys worldwide is the 24-HDR (24 h dietary recall, occasionally administered repeatedly, mostly using interview software. Only three countries have incorporated their national food consumption surveys into continuous national health and nutrition examination surveys.

  7. National Survey on Access, Use and Promotion of Rational Use of Medicines (PNAUM: household survey component methods

    Directory of Open Access Journals (Sweden)

    Sotero Serrate Mengue

    Full Text Available ABSTRACT OBJECTIVE To describe methodological aspects of the household survey National Survey on Access, Use and Promotion of Rational Use of Medicines (PNAUM related to sampling design and implementation, the actual obtained sample, instruments and fieldwork. METHODS A cross-sectional, population-based study with probability sampling in three stages of the population living in households located in Brazilian urban areas. Fieldwork was carried out between September 2013 and February 2014. The data collection instrument included questions related to: information about households, residents and respondents; chronic diseases and medicines used; use of health services; acute diseases and events treated with drugs; use of contraceptives; use of pharmacy services; behaviors that may affect drug use; package inserts and packaging; lifestyle and health insurance. RESULTS In total, 41,433 interviews were carried out in 20,404 households and 576 urban clusters corresponding to 586 census tracts distributed in the five Brazilian regions, according to eight domains defined by age and gender. CONCLUSIONS The results of the survey may be used as a baseline for future studies aiming to assess the impact of government action on drug access and use. For local studies using a compatible method, PNAUM may serve as a reference point to evaluate variations in space and population. With a comprehensive evaluation of drug-related aspects, PNAUM is a major source of data for a variety of analyses to be carried out both at academic and government level.

  8. Measuring Nonresponse Bias in a Cross-Country Enterprise Survey

    Directory of Open Access Journals (Sweden)

    Katarzyna Bańkowska

    2015-04-01

    Full Text Available Nonresponse is a common issue affecting the vast majority of surveys. Efforts to convince those unwilling to participate in a survey might not necessary result in a better picture of the target population and can lead to higher, not lower, nonresponse bias.We investigate the impact of non-response in the European Commission & European Central Bank Survey on the Access to Finance of Enterprises (SAFE, which collects evidence on the financing conditions faced by European SMEs compared with those of large firms. This survey, conducted by telephone bi-annually since 2009 by the ECB and the European Commission, provides a valuable means to search for this kind of bias, given the high heterogeneity of response propensities across countries.The study relies on so-called “Representativity Indicators” developed within the Representativity Indicators of Survey Quality (RISQ project, which measure the distance to a fully representative response. On this basis, we examine the quality of the SAFE Survey at different stages of the fieldwork as well as across different survey waves and countries. The RISQ methodology relies on rich sampling frame information, which is however partly limited in the case of the SAFE. We also assess the representativeness of the SAFE particular subsample created by linking the survey responses with the companies’ financial information from a business register; this sub-sampling is another potential source of bias which we also attempt to quantify. Finally, we suggest possible ways how to improve monitoring of the possible nonresponse bias in the future rounds of the survey.

  9. The Lyα reference sample. I. Survey outline and first results for Markarian 259

    International Nuclear Information System (INIS)

    Östlin, Göran; Hayes, Matthew; Duval, Florent; Sandberg, Andreas; Rivera-Thorsen, Thøger; Marquart, Thomas; Adamo, Angela; Melinder, Jens; Guaita, Lucia; Micheva, Genoveva; Orlitová, Ivana; Atek, Hakim; Cannon, John M.; Pardy, Stephen A.; Gruyters, Pieter; Herenz, Edmund Christian; Kunth, Daniel; Laursen, Peter; Mas-Hesse, J. Miguel; Otí-Floranes, Héctor

    2014-01-01

    The Lyα Reference Sample (LARS) is a substantial program with the Hubble Space Telescope (HST) that provides a sample of local universe laboratory galaxies in which to study the detailed astrophysics of the visibility and strength of the Lyαline of neutral hydrogen. Lyα is the dominant spectral line in use for characterizing high-redshift (z) galaxies. This paper presents an overview of the survey, its selection function, and HST imaging observations. The sample was selected from the combined GALEX+Sloan Digital Sky Survey catalog at z = 0.028-0.19, in order to allow Lyα to be captured with combinations of long-pass filters in the Solar Blind Channel (SBC) of the Advanced Camera for Surveys (ACS) onboard HST. In addition, LARS utilizes Hα and Hβ narrowband and u, b, i broadband imaging with ACS and the Wide Field Camera 3 (WFC3). In order to study galaxies in which large numbers of Lyα photons are produced (whether or not they escape), we demanded an Hα equivalent width W(Hα) ≥100 Å. The final sample of 14 galaxies covers far-UV (FUV, λ ∼ 1500 Å) luminosities that overlap with those of high-z Lyα emitters (LAEs) and Lyman break galaxies (LBGs), making LARS a valid comparison sample. We present the reduction steps used to obtain the Lyα images, including our LARS eXtraction software (LaXs), which utilizes pixel-by-pixel spectral synthesis fitting of the energy distribution to determine and subtract the continuum at Lyα. We demonstrate that the use of SBC long-pass-filter combinations increase the signal-to-noise ratio by an order of magnitude compared to the nominal Lyα filter available in SBC. To exemplify the science potential of LARS, we also present some first results for a single galaxy, Mrk 259 (LARS #1). This irregular galaxy shows bright and extended (indicative of resonance scattering) but strongly asymmetric Lyα emission. Spectroscopy from the Cosmic Origins Spectrograph on board HST centered on the brightest UV knot shows a moderate

  10. The Lyα reference sample. I. Survey outline and first results for Markarian 259

    Energy Technology Data Exchange (ETDEWEB)

    Östlin, Göran; Hayes, Matthew; Duval, Florent; Sandberg, Andreas; Rivera-Thorsen, Thøger; Marquart, Thomas; Adamo, Angela; Melinder, Jens; Guaita, Lucia; Micheva, Genoveva [Department of Astronomy, Stockholm University, Oscar Klein Centre, AlbaNova, Stockholm SE-106 91 (Sweden); Orlitová, Ivana [Observatoire de Genève, Université de Genève, Chemin des Maillettes 51, 1290 Versoix (Switzerland); Atek, Hakim [Laboratoire d' Astrophysique, Ecole Polytechnique Fédérale de Lausanne, Observatoire de Sauverny, CH-1290 Versoix (Switzerland); Cannon, John M.; Pardy, Stephen A. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Gruyters, Pieter [Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala (Sweden); Herenz, Edmund Christian [Leibniz-Institute for Astrophysics Potsdam (AIP), innoFSPEC, An der Sternwarte 16, D-14482 Potsdam (Germany); Kunth, Daniel [Institut d' Astrophysique Paris, 98bis Bd Arago, F-75014 Paris (France); Laursen, Peter [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen (Denmark); Mas-Hesse, J. Miguel [Centro de Astrobiologa (CSIC-INTA), Departamento de Astrofsica, POB 78, E-28691, Villanueva de la Cañada (Spain); Otí-Floranes, Héctor [Instituto de Astronoma, Universidad Nacional Autnoma de Mxico, Apdo. Postal 106, Ensenada B. C. 22800 (Mexico); and others

    2014-12-10

    The Lyα Reference Sample (LARS) is a substantial program with the Hubble Space Telescope (HST) that provides a sample of local universe laboratory galaxies in which to study the detailed astrophysics of the visibility and strength of the Lyαline of neutral hydrogen. Lyα is the dominant spectral line in use for characterizing high-redshift (z) galaxies. This paper presents an overview of the survey, its selection function, and HST imaging observations. The sample was selected from the combined GALEX+Sloan Digital Sky Survey catalog at z = 0.028-0.19, in order to allow Lyα to be captured with combinations of long-pass filters in the Solar Blind Channel (SBC) of the Advanced Camera for Surveys (ACS) onboard HST. In addition, LARS utilizes Hα and Hβ narrowband and u, b, i broadband imaging with ACS and the Wide Field Camera 3 (WFC3). In order to study galaxies in which large numbers of Lyα photons are produced (whether or not they escape), we demanded an Hα equivalent width W(Hα) ≥100 Å. The final sample of 14 galaxies covers far-UV (FUV, λ ∼ 1500 Å) luminosities that overlap with those of high-z Lyα emitters (LAEs) and Lyman break galaxies (LBGs), making LARS a valid comparison sample. We present the reduction steps used to obtain the Lyα images, including our LARS eXtraction software (LaXs), which utilizes pixel-by-pixel spectral synthesis fitting of the energy distribution to determine and subtract the continuum at Lyα. We demonstrate that the use of SBC long-pass-filter combinations increase the signal-to-noise ratio by an order of magnitude compared to the nominal Lyα filter available in SBC. To exemplify the science potential of LARS, we also present some first results for a single galaxy, Mrk 259 (LARS #1). This irregular galaxy shows bright and extended (indicative of resonance scattering) but strongly asymmetric Lyα emission. Spectroscopy from the Cosmic Origins Spectrograph on board HST centered on the brightest UV knot shows a moderate

  11. Hard bottom substate monitoring Horns Rev offshore wind farm 2004. Survey report no. 1

    Energy Technology Data Exchange (ETDEWEB)

    Frederiksen, Rune

    2004-05-15

    In connection with the implementation of the monitoring programme concerning the ecological implication of the effect of the introduction of hard substrate related to the Horns Rev Wind Farm, the third survey was carried out in the period 2431 March 2004. The survey covered collection of fauna and flora samples from the scour protection and at the wind turbine towers at six turbine sites. Video recordings were planned at different sites to provide documentation, but due to poor visibility the video recordings were postponed. On request from Elsam Engineering A/S video inspections on technical installations were made at turbine '84 and 95. This report covers a short description of the methodology, sampling activities and site description. (au)

  12. Methodologies for the Extraction of Phenolic Compounds from Environmental Samples: New Approaches

    Directory of Open Access Journals (Sweden)

    Cristina Mahugo Santana

    2009-01-01

    Full Text Available Phenolic derivatives are among the most important contaminants present in the environment. These compounds are used in several industrial processes to manufacture chemicals such as pesticides, explosives, drugs and dyes. They also are used in the bleaching process of paper manufacturing. Apart from these sources, phenolic compounds have substantial applications in agriculture as herbicides, insecticides and fungicides. However, phenolic compounds are not only generated by human activity, but they are also formed naturally, e.g., during the decomposition of leaves or wood. As a result of these applications, they are found in soils and sediments and this often leads to wastewater and ground water contamination. Owing to their high toxicity and persistence in the environment, both, the US Environmental Protection Agency (EPA and the European Union have included some of them in their lists of priority pollutants. Current standard methods of phenolic compounds analysis in water samples are based on liquid–liquid extraction (LLE while Soxhlet extraction is the most used technique for isolating phenols from solid matrices. However, these techniques require extensive cleanup procedures that are time-intensive and involve expensive and hazardous organic solvents, which are undesirable for health and disposal reasons. In the last years, the use of news methodologies such as solid-phase extraction (SPE and solid-phase microextraction (SPME have increased for the extraction of phenolic compounds from liquid samples. In the case of solid samples, microwave assisted extraction (MAE is demonstrated to be an efficient technique for the extraction of these compounds. In this work we review the developed methods in the extraction and determination of phenolic derivatives in different types of environmental matrices such as water, sediments and soils. Moreover, we present the new approach in the use of micellar media coupled with SPME process for the

  13. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods

    International Nuclear Information System (INIS)

    Kleinschmidt, R.; Watson, D.

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km 2 ), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h −1 (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. - Highlights: • A baseline terrestrial air kerma map of Queensland, Australia was developed using geochemical data from a major drainage catchment ultra-low density sampling program

  14. Comparing Two Survey Research Approaches: E-Mail and Web-Based Technology versus Traditional Mail.

    Science.gov (United States)

    Howes, Colleen M.; Mailloux, Mark R.

    2001-01-01

    Contrasted two survey methodologies: e-mail-Web and traditional mail. Found that: (1) e-mail-Web respondents were proportionately more likely to be male and enrolled in school full-time; (2) more individual question non-response was present for the e-mail-Web sample; and (3) e-mail-Web respondents value different aspects of graduate school. (EV)

  15. Creel survey sampling designs for estimating effort in short-duration Chinook salmon fisheries

    Science.gov (United States)

    McCormick, Joshua L.; Quist, Michael C.; Schill, Daniel J.

    2013-01-01

    Chinook Salmon Oncorhynchus tshawytscha sport fisheries in the Columbia River basin are commonly monitored using roving creel survey designs and require precise, unbiased catch estimates. The objective of this study was to examine the relative bias and precision of total catch estimates using various sampling designs to estimate angling effort under the assumption that mean catch rate was known. We obtained information on angling populations based on direct visual observations of portions of Chinook Salmon fisheries in three Idaho river systems over a 23-d period. Based on the angling population, Monte Carlo simulations were used to evaluate the properties of effort and catch estimates for each sampling design. All sampling designs evaluated were relatively unbiased. Systematic random sampling (SYS) resulted in the most precise estimates. The SYS and simple random sampling designs had mean square error (MSE) estimates that were generally half of those observed with cluster sampling designs. The SYS design was more efficient (i.e., higher accuracy per unit cost) than a two-cluster design. Increasing the number of clusters available for sampling within a day decreased the MSE of estimates of daily angling effort, but the MSE of total catch estimates was variable depending on the fishery. The results of our simulations provide guidelines on the relative influence of sample sizes and sampling designs on parameters of interest in short-duration Chinook Salmon fisheries.

  16. Nonprobability Web Surveys to Measure Sexual Behaviors and Attitudes in the General Population: A Comparison With a Probability Sample Interview Survey

    Science.gov (United States)

    Burkill, Sarah; Couper, Mick P; Conrad, Frederick; Clifton, Soazig; Tanton, Clare; Phelps, Andrew; Datta, Jessica; Mercer, Catherine H; Sonnenberg, Pam; Prah, Philip; Mitchell, Kirstin R; Wellings, Kaye; Johnson, Anne M; Copas, Andrew J

    2014-01-01

    Background Nonprobability Web surveys using volunteer panels can provide a relatively cheap and quick alternative to traditional health and epidemiological surveys. However, concerns have been raised about their representativeness. Objective The aim was to compare results from different Web panels with a population-based probability sample survey (n=8969 aged 18-44 years) that used computer-assisted self-interview (CASI) for sensitive behaviors, the third British National Survey of Sexual Attitudes and Lifestyles (Natsal-3). Methods Natsal-3 questions were included on 4 nonprobability Web panel surveys (n=2000 to 2099), 2 using basic quotas based on age and sex, and 2 using modified quotas based on additional variables related to key estimates. Results for sociodemographic characteristics were compared with external benchmarks and for sexual behaviors and opinions with Natsal-3. Odds ratios (ORs) were used to express differences between the benchmark data and each survey for each variable of interest. A summary measure of survey performance was the average absolute OR across variables. Another summary measure was the number of key estimates for which the survey differed significantly (at the 5% level) from the benchmarks. Results For sociodemographic variables, the Web surveys were less representative of the general population than Natsal-3. For example, for men, the average absolute OR for Natsal-3 was 1.14, whereas for the Web surveys the average absolute ORs ranged from 1.86 to 2.30. For all Web surveys, approximately two-thirds of the key estimates of sexual behaviors were different from Natsal-3 and the average absolute ORs ranged from 1.32 to 1.98. Differences were appreciable even for questions asked by CASI in Natsal-3. No single Web survey performed consistently better than any other did. Modified quotas slightly improved results for men, but not for women. Conclusions Consistent with studies from other countries on less sensitive topics, volunteer Web

  17. Methodological aspects on microdialysis sampling and measurements

    OpenAIRE

    Abrahamsson, Pernilla

    2010-01-01

    Background:     The microdialysis (MD) technique is widely spread and used both experi­mentally and in clinical practice. The MD technique allows continuous collection of small molecules such as glucose, lactate, pyruvate and glycerol. Samples are often analysed using the CMA 600 analyser, an enzymatic and colorimetric analyser.  Data evaluating the performance of the CMA 600 analysis system and associated sample han­dling are sparse. The aim of this work was to identify sources of variabilit...

  18. What Are Probability Surveys used by the National Aquatic Resource Surveys?

    Science.gov (United States)

    The National Aquatic Resource Surveys (NARS) use probability-survey designs to assess the condition of the nation’s waters. In probability surveys (also known as sample-surveys or statistical surveys), sampling sites are selected randomly.

  19. Don't spin the pen: two alternative methods for second-stage sampling in urban cluster surveys

    Directory of Open Access Journals (Sweden)

    Rose Angela MC

    2007-06-01

    Full Text Available Abstract In two-stage cluster surveys, the traditional method used in second-stage sampling (in which the first household in a cluster is selected is time-consuming and may result in biased estimates of the indicator of interest. Firstly, a random direction from the center of the cluster is selected, usually by spinning a pen. The houses along that direction are then counted out to the boundary of the cluster, and one is then selected at random to be the first household surveyed. This process favors households towards the center of the cluster, but it could easily be improved. During a recent meningitis vaccination coverage survey in Maradi, Niger, we compared this method of first household selection to two alternatives in urban zones: 1 using a superimposed grid on the map of the cluster area and randomly selecting an intersection; and 2 drawing the perimeter of the cluster area using a Global Positioning System (GPS and randomly selecting one point within the perimeter. Although we only compared a limited number of clusters using each method, we found the sampling grid method to be the fastest and easiest for field survey teams, although it does require a map of the area. Selecting a random GPS point was also found to be a good method, once adequate training can be provided. Spinning the pen and counting households to the boundary was the most complicated and time-consuming. The two methods tested here represent simpler, quicker and potentially more robust alternatives to spinning the pen for cluster surveys in urban areas. However, in rural areas, these alternatives would favor initial household selection from lower density (or even potentially empty areas. Bearing in mind these limitations, as well as available resources and feasibility, investigators should choose the most appropriate method for their particular survey context.

  20. 618-11 Burial Ground USRADS radiological surveys

    International Nuclear Information System (INIS)

    Wendling, M.A.

    1994-01-01

    This report summarizes and documents the results of the radiological surveys conducted from February 4 through February 10, 1993 over the 618-11 Burial Ground, Hanford Site, Richland, Washington. In addition, this report explains the survey methodology using the Ultrasonic Ranging and Data System (USRADS). The 618-11 Burial Ground radiological survey field task consisted of two activities: characterization of the specific background conditions and the radiological survey of the area. The radiological survey of the 618-11 Burial Ground, along with the background study, were conducted by Site Investigative Surveys Environmental Restoration Health Physics Organization of the Westinghouse Hanford Company. The survey methodology was based on utilization of the Ultrasonic Ranging and Data System (USRADS) for automated recording of the gross gamma radiation levels at or near six (6) inches and at three (3) feet from the surface soil

  1. Non-governmental organizations assisting victims of crime in Belgrade: Survey results

    Directory of Open Access Journals (Sweden)

    Milivojević Sanja K.

    2003-01-01

    Full Text Available This paper presents the results of survey regarding non-governmental organizations assisting victims of crime in Belgrade. The survey was completed at the end of 2002 for purposes of establishing a Victim Support Service in Serbia. In introduction authors give a short review of victim support services development in the World and the region, explaining the need for such service in Serbia, the subject and the aim of the article as well as the purpose of the survey. Second part of the paper contains the sample, methodology and the aim of the interview with NGO representatives. In the third section authors present the analysis of the survey data. Finally, in conclusion authors summarize the data and observed problems, suggestions for possible solution and directions of future development of services and organizations assisting victims of crime in Serbia.

  2. Variations in PET/CT methodology for oncologic imaging at U.S. academic medical centers: an imaging response assessment team survey.

    Science.gov (United States)

    Graham, Michael M; Badawi, Ramsey D; Wahl, Richard L

    2011-02-01

    In 2005, 8 Imaging Response Assessment Teams (IRATs) were funded by the National Cancer Institute (NCI) as supplemental grants to existing NCI Cancer Centers. After discussion among the IRATs regarding the need for increased standardization of clinical and research PET/CT methodology, it became apparent that data acquisition and processing approaches differ considerably among centers. To determine the variability in detail, a survey of IRAT sites and IRAT affiliates was performed. A 34-question instrument evaluating patient preparation, scanner type, performance approach, display, and analysis was developed. Fifteen institutions, including the 8 original IRATs and 7 institutions that had developed affiliate IRATs, were surveyed. The major areas of variation were (18)F-FDG dose (259-740 MBq [7-20 mCi]) uptake time (45-90 min), sedation (never to frequently), handling of diabetic patients, imaging time (2-7 min/bed position), performance of diagnostic CT scans as a part of PET/CT, type of acquisition (2-dimensional vs. 3-dimensional), CT technique, duration of fasting (4 or 6 h), and (varying widely) acquisition, processing, display, and PACS software--with 4 sites stating that poor-quality images appear on PACS. There is considerable variability in the way PET/CT scans are performed at academic institutions that are part of the IRAT network. This variability likely makes it difficult to quantitatively compare studies performed at different centers. These data suggest that additional standardization in methodology will be required so that PET/CT studies, especially those performed quantitatively, are more comparable across sites.

  3. Cross-continental comparison of national food consumption survey methods--a narrative review

    Science.gov (United States)

    Food consumption surveys are performed in many countries. Comparison of results from those surveys across nations is difficult because of differences in methodological approaches. While consensus about the preferred methodology associated with national food consumption surveys is increasing, no in...

  4. THE CHANDRA COSMOS-LEGACY SURVEY: THE z > 3 SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Marchesi, S.; Civano, F.; Urry, C. M. [Yale Center for Astronomy and Astrophysics, 260 Whitney Avenue, New Haven, CT 06520 (United States); Salvato, M. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei München (Germany); Shankar, F. [Department of Physics and Astronomy, University of Southampton, Highfield, SO17 1BJ (United Kingdom); Comastri, A.; Lanzuisi, G.; Vignali, C.; Zamorani, G.; Brusa, M.; Gilli, R. [INAF–Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna (Italy); Elvis, M. [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Trakhtenbrot, B.; Schawinski, K. [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Allevato, V. [Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2a, FI-00014 Helsinki (Finland); Fiore, F. [INAF–Osservatorio Astronomico di Roma, via di Frascati 33, I-00040 Monte Porzio Catone (Italy); Griffiths, R. [Physics and Astronomy Department, Natural Sciences Division, University of Hawaii at Hilo, 200 W. Kawili Street, Hilo, HI 96720 (United States); Hasinger, G. [Institute for Astronomy, 2680 Woodlawn Drive, University of Hawaii, Honolulu, HI 96822 (United States); Miyaji, T. [Instituto de Astronomía sede Ensenada, Universidad Nacional Autónoma de México, Km. 103, Carret. Tijunana-Ensenada, Ensenada, BC (Mexico); Treister, E. [Universidad de Concepción, Departamento de Astronomía, Casilla 160-C, Concepción (Chile)

    2016-08-20

    We present the largest high-redshift (3 < z < 6.85) sample of X-ray-selected active galactic nuclei (AGNs) on a contiguous field, using sources detected in the Chandra COSMOS-Legacy survey. The sample contains 174 sources, 87 with spectroscopic redshift and the other 87 with photometric redshift (z {sub phot}). In this work, we treat z {sub phot} as a probability-weighted sum of contributions, adding to our sample the contribution of sources with z {sub phot} < 3 but z {sub phot} probability distribution >0 at z > 3. We compute the number counts in the observed 0.5–2 keV band, finding a decline in the number of sources at z > 3 and constraining phenomenological models of the X-ray background. We compute the AGN space density at z > 3 in two different luminosity bins. At higher luminosities (log L (2–10 keV) > 44.1 erg s{sup −1}), the space density declines exponentially, dropping by a factor of ∼20 from z ∼ 3 to z ∼ 6. The observed decline is ∼80% steeper at lower luminosities (43.55 erg s{sup −1} < logL(2–10 keV) < 44.1 erg s{sup −1}) from z ∼ 3 to z ∼ 4.5. We study the space density evolution dividing our sample into optically classified Type 1 and Type 2 AGNs. At log L (2–10 keV) > 44.1 erg s{sup −1}, unobscured and obscured objects may have different evolution with redshift, with the obscured component being three times higher at z ∼ 5. Finally, we compare our space density with predictions of quasar activation merger models, whose calibration is based on optically luminous AGNs. These models significantly overpredict the number of expected AGNs at log L (2–10 keV) > 44.1 erg s{sup −1} with respect to our data.

  5. Positive Community Norm Survey 2011 : Methodology and Results

    Science.gov (United States)

    2012-09-01

    This survey established a baseline understanding of the positive norms that exist in Idaho, plus reveal the gaps in knowledge and perceived norms with regard to impaired driving. These gaps will indicate the most effective opportunities for future co...

  6. Assessing importance and satisfaction judgments of intermodal work commuters with electronic survey methodology.

    Science.gov (United States)

    2013-09-01

    Recent advances in multivariate methodology provide an opportunity to further the assessment of service offerings in public transportation for work commuting. We offer methodologies that are alternative to direct rating scale and have advantages in t...

  7. Deployment of paired pushnets from jet-propelled kayaks to sample ichthyoplankton

    Science.gov (United States)

    Acre, Matthew R.; Grabowski, Timothy B.

    2015-01-01

    Accessing and effectively sampling the off-channel habitats that are considered crucial for early life stages of freshwater fishes constitute a difficult challenge when common ichthyoplankton survey methods, such as push nets, are used. We describe a new method of deploying push nets from jet-propelled kayaks to enable the sampling of previously inaccessible off-channel habitats. The described rig is also functional in more open and accessible habitats, such as the main channel of rivers or reservoirs. Although further evaluation is necessary to ensure that results are comparable across studies, the described push-net system offers a statistically rigorous methodology that generates replicate samples from a wide range of freshwater habitats that were previously inaccessible to this gear type.

  8. Toward decentralized analysis of mercury (II) in real samples. A critical review on nanotechnology-based methodologies.

    Science.gov (United States)

    Botasini, Santiago; Heijo, Gonzalo; Méndez, Eduardo

    2013-10-24

    In recent years, it has increased the number of works focused on the development of novel nanoparticle-based sensors for mercury detection, mainly motivated by the need of low cost portable devices capable of giving fast and reliable analytical response, thus contributing to the analytical decentralization. Methodologies employing colorimetric, fluorometric, magnetic, and electrochemical output signals allowed reaching detection limits within the pM and nM ranges. Most of these developments proved their suitability in detecting and quantifying mercury (II) ions in synthetic solutions or spiked water samples. However, the state of art in these technologies is still behind the standard methods of mercury quantification, such as cold vapor atomic absorption spectrometry and inductively coupled plasma techniques, in terms of reliability and sensitivity. This is mainly because the response of nanoparticle-based sensors is highly affected by the sample matrix. The developed analytical nanosystems may fail in real samples because of the negative incidence of the ionic strength and the presence of exchangeable ligands. The aim of this review is to critically consider the recently published innovations in this area, and highlight the needs to include more realistic assays in future research in order to make these advances suitable for on-site analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Improving the collection of knowledge, attitude and practice data with community surveys: a comparison of two second-stage sampling methods.

    Science.gov (United States)

    Davis, Rosemary H; Valadez, Joseph J

    2014-12-01

    Second-stage sampling techniques, including spatial segmentation, are widely used in community health surveys when reliable household sampling frames are not available. In India, an unresearched technique for household selection is used in eight states, which samples the house with the last marriage or birth as the starting point. Users question whether this last-birth or last-marriage (LBLM) approach introduces bias affecting survey results. We conducted two simultaneous population-based surveys. One used segmentation sampling; the other used LBLM. LBLM sampling required modification before assessment was possible and a more systematic approach was tested using last birth only. We compared coverage proportions produced by the two independent samples for six malaria indicators and demographic variables (education, wealth and caste). We then measured the level of agreement between the caste of the selected participant and the caste of the health worker making the selection. No significant difference between methods was found for the point estimates of six malaria indicators, education, caste or wealth of the survey participants (range of P: 0.06 to >0.99). A poor level of agreement occurred between the caste of the health worker used in household selection and the caste of the final participant, (Κ = 0.185), revealing little association between the two, and thereby indicating that caste was not a source of bias. Although LBLM was not testable, a systematic last-birth approach was tested. If documented concerns of last-birth sampling are addressed, this new method could offer an acceptable alternative to segmentation in India. However, inter-state caste variation could affect this result. Therefore, additional assessment of last birth is required before wider implementation is recommended. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2013; all rights reserved.

  10. Genetic effects of radiation in man: a critical analysis of methodology with examples from three surveys among Brazilian physicians

    International Nuclear Information System (INIS)

    Freire-Maia, N.

    1978-01-01

    Information obtained through three different surveys (two via mail and one through personal interviews) made among Brazilian physicians in presented. Data have been classified according to survey, medical speciality, protection used and pregnancy order. Events under consideration are abortions, stillbirths, neo-natal mortality, infant-juvenile mortality (under two criteria) and sex ratio. A number of statistically significant diferences have been found in the direction expected according to the radio-genetics theory and a few ones against it. Two of the surveys reveal an effect of the pregnancy order an abortions which was larger in the exposed samples than in the control ones. This fact could be due to radiation-induced genetic damage, especially chromosome aberrations [pt

  11. Optimal Allocation of Sampling Effort in Depletion Surveys

    Science.gov (United States)

    We consider the problem of designing a depletion or removal survey as part of estimating animal abundance for populations with imperfect capture or detection rates. In a depletion survey, animals are captured from a given area, counted, and withheld from the population. This proc...

  12. Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida

    Energy Technology Data Exchange (ETDEWEB)

    Vinick, Charles; Riccobono, Antonino, MS; Messing, Charles G., Ph.D.; Walker, Brian K., Ph.D.; Reed, John K., Ph.D.

    2012-02-28

    Dehlsen Associates, LLC was awarded a grant by the United States Department of Energy (DOE) Golden Field Office for a project titled 'Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida,' corresponding to DOE Grant Award Number DE-EE0002655 resulting from DOE funding Opportunity Announcement Number DE-FOA-0000069 for Topic Area 2, and it is referred to herein as 'the project.' The purpose of the project was to enhance the certainty of the survey requirements and regulatory review processes for the purpose of reducing the time, efforts, and costs associated with initial siting efforts of marine and hydrokinetic energy conversion facilities that may be proposed in the Atlantic Ocean offshore Southeast Florida. To secure early input from agencies, protocols were developed for collecting baseline geophysical information and benthic habitat data that can be used by project developers and regulators to make decisions early in the process of determining project location (i.e., the siting process) that avoid or minimize adverse impacts to sensitive marine benthic habitat. It is presumed that such an approach will help facilitate the licensing process for hydrokinetic and other ocean renewable energy projects within the study area and will assist in clarifying the baseline environmental data requirements described in the U.S. Department of the Interior Bureau of Ocean Energy Management, Regulation and Enforcement (formerly Minerals Management Service) final regulations on offshore renewable energy (30 Code of Federal Regulations 285, published April 29, 2009). Because projects generally seek to avoid or minimize impacts to sensitive marine habitats, it was not the intent of this project to investigate areas that did not appear suitable for the siting of ocean renewable energy projects. Rather, a two-tiered approach was designed with the first step consisting of gaining overall insight

  13. Review and evaluation of paleohydrologic methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Foley, M.G.; Zimmerman, D.A.; Doesburg, J.M.; Thorne, P.D.

    1982-12-01

    A literature review was conducted to identify methodologies that could be used to interpret paleohydrologic environments. Paleohydrology is the study of past hydrologic systems or of the past behavior of an existing hydrologic system. The purpose of the review was to evaluate how well these methodologies could be applied to the siting of low-level radioactive waste facilities. The computer literature search queried five bibliographical data bases containing over five million citations of technical journals, books, conference papers, and reports. Two data-base searches (United States Geological Survey - USGS) and a manual search were also conducted. The methodologies were examined for data requirements and sensitivity limits. Paleohydrologic interpretations are uncertain because of the effects of time on hydrologic and geologic systems and because of the complexity of fluvial systems. Paleoflow determinations appear in many cases to be order-of-magnitude estimates. However, the methodologies identified in this report mitigate this uncertainty when used collectively as well as independently. That is, the data from individual methodologies can be compared or combined to corroborate hydrologic predictions. In this manner, paleohydrologic methodologies are viable tools to assist in evaluating the likely future hydrology of low-level radioactive waste sites.

  14. Review and evaluation of paleohydrologic methodologies

    International Nuclear Information System (INIS)

    Foley, M.G.; Zimmerman, D.A.; Doesburg, J.M.; Thorne, P.D.

    1982-12-01

    A literature review was conducted to identify methodologies that could be used to interpret paleohydrologic environments. Paleohydrology is the study of past hydrologic systems or of the past behavior of an existing hydrologic system. The purpose of the review was to evaluate how well these methodologies could be applied to the siting of low-level radioactive waste facilities. The computer literature search queried five bibliographical data bases containing over five million citations of technical journals, books, conference papers, and reports. Two data-base searches (United States Geological Survey - USGS) and a manual search were also conducted. The methodologies were examined for data requirements and sensitivity limits. Paleohydrologic interpretations are uncertain because of the effects of time on hydrologic and geologic systems and because of the complexity of fluvial systems. Paleoflow determinations appear in many cases to be order-of-magnitude estimates. However, the methodologies identified in this report mitigate this uncertainty when used collectively as well as independently. That is, the data from individual methodologies can be compared or combined to corroborate hydrologic predictions. In this manner, paleohydrologic methodologies are viable tools to assist in evaluating the likely future hydrology of low-level radioactive waste sites

  15. Rapid Active Sampling Surveys as a Tool to Evaluate Factors Associated with Acute Gastroenteritis and Norovirus Infection among Children in Rural Guatemala.

    Science.gov (United States)

    Olson, Daniel; Lamb, Molly M; Lopez, Maria R; Paniagua-Avila, Maria A; Zacarias, Alma; Samayoa-Reyes, Gabriela; Cordon-Rosales, Celia; Asturias, Edwin J

    2017-09-01

    We examined burden and factors associated with norovirus (NoV) acute gastroenteritis (AGE) among children in rural Guatemala. Children age 6 weeks to 17 years were enrolled into three AGE surveillance groups, using two-stage cluster sampling: a prospective participatory syndromic surveillance (PSS) cohort and two cross-sectional rapid active sampling (RAS) surveys, conducted from April 2015 to February 2016. Epidemiologic and NoV testing data were used to identify factors associated with NoV infection, AGE, and NoV+ AGE. The three cross-sectional surveys (PSS enrollment visit, RAS Survey 1, and RAS Survey 2) enrolled 1,239 children, who reported 134 (11%) AGE cases, with 20% of AGE and 11% of non-AGE samples positive for NoV. Adjusted analyses identified several modifiable factors associated with AGE and NoV infection. The cross-sectional RAS surveys were practical and cost-effective in identifying population-level risk factors for AGE and NoV, supporting their use as a tool to direct limited public health resources toward high-risk populations.

  16. Comparing the performance of cluster random sampling and integrated threshold mapping for targeting trachoma control, using computer simulation.

    Directory of Open Access Journals (Sweden)

    Jennifer L Smith

    Full Text Available Implementation of trachoma control strategies requires reliable district-level estimates of trachomatous inflammation-follicular (TF, generally collected using the recommended gold-standard cluster randomized surveys (CRS. Integrated Threshold Mapping (ITM has been proposed as an integrated and cost-effective means of rapidly surveying trachoma in order to classify districts according to treatment thresholds. ITM differs from CRS in a number of important ways, including the use of a school-based sampling platform for children aged 1-9 and a different age distribution of participants. This study uses computerised sampling simulations to compare the performance of these survey designs and evaluate the impact of varying key parameters.Realistic pseudo gold standard data for 100 districts were generated that maintained the relative risk of disease between important sub-groups and incorporated empirical estimates of disease clustering at the household, village and district level. To simulate the different sampling approaches, 20 clusters were selected from each district, with individuals sampled according to the protocol for ITM and CRS. Results showed that ITM generally under-estimated the true prevalence of TF over a range of epidemiological settings and introduced more district misclassification according to treatment thresholds than did CRS. However, the extent of underestimation and resulting misclassification was found to be dependent on three main factors: (i the district prevalence of TF; (ii the relative risk of TF between enrolled and non-enrolled children within clusters; and (iii the enrollment rate in schools.Although in some contexts the two methodologies may be equivalent, ITM can introduce a bias-dependent shift as prevalence of TF increases, resulting in a greater risk of misclassification around treatment thresholds. In addition to strengthening the evidence base around choice of trachoma survey methodologies, this study illustrates

  17. Nationwide survey of policies and practices related to capillary blood sampling in medical laboratories in Croatia

    OpenAIRE

    Lenicek Krleza, Jasna

    2014-01-01

    Introduction: Capillary sampling is increasingly used to obtain blood for laboratory tests in volumes as small as necessary and as non-invasively as possible. Whether capillary blood sampling is also frequent in Croatia, and whether it is performed according to international laboratory standards is unclear. Materials and methods: All medical laboratories that participate in the Croatian National External Quality Assessment Program (N = 204) were surveyed on-line to collect information about t...

  18. Validation of the Technology Acceptance Measure for Pre-Service Teachers (TAMPST) on a Malaysian Sample: A Cross-Cultural Study

    Science.gov (United States)

    Teo, Timothy

    2010-01-01

    Purpose: The purpose of this paper is to assess the cross-cultural validity of the technology acceptance measure for pre-service teachers (TAMPST) on a Malaysian sample. Design/methodology/approach: A total of 193 pre-service teachers from a Malaysian university completed a survey questionnaire measuring their responses to five constructs in the…

  19. Spread of Traditional Medicines in India: Results of National Sample Survey Organization's Perception Survey on Use of AYUSH.

    Science.gov (United States)

    Srinivasan, R; Sugumar, V Raji

    2015-10-04

    For the first time, we have a comprehensive database on usage of AYUSH (acronym for Ayurveda, naturopathy and Yoga, Unani, Siddha, and Homeopathy) in India at the household level. This article aims at exploring the spread of the traditional medical systems in India and the perceptions of people on the access and effectiveness of these medical systems using this database. The article uses the unit level data purchased from the National Sample Survey Organization, New Delhi. Household is the basic unit of survey and the data are the collective opinion of the household. This survey shows that less than 30% of Indian households use the traditional medical systems. There is also a regional pattern in the usage of particular type of traditional medicine, reflecting the regional aspects of the development of such medical systems. The strong faith in AYUSH is the main reason for its usage; lack of need for AYUSH and lack of awareness about AYUSH are the main reasons for not using it. With regard to source of medicines in the traditional medical systems, home is the main source in the Indian medical system and private sector is the main source in Homeopathy. This shows that there is need for creating awareness and improving access to traditional medical systems in India. By and large, the users of AYUSH are also convinced about the effectiveness of these traditional medicines. © The Author(s) 2015.

  20. International survey blauwe wijting. Elke seconde een sample

    NARCIS (Netherlands)

    Faessler, S.M.M.

    2011-01-01

    IJMuiden- in 2011 wordt voor het eerst de jaarlijkse blauwe wijting survey gecoördineerd door Schascha Fässler, geboren Zwitser en sinds 2009 als 'fisheries acoustics' scientist' werkzaam bij IMARES in IJmuiden. In onderstaand artikel gaat Fässler nader in op acoustics in het algemeen en de survey

  1. Robustness of Adaptive Survey Designs to Inaccuracy of Design Parameters

    Directory of Open Access Journals (Sweden)

    Burger Joep

    2017-09-01

    Full Text Available Adaptive survey designs (ASDs optimize design features, given 1 the interactions between the design features and characteristics of sampling units and 2 a set of constraints, such as a budget and a minimum number of respondents. Estimation of the interactions is subject to both random and systematic error. In this article, we propose and evaluate four viewpoints to assess robustness of ASDs to inaccuracy of design parameter estimates: the effect of both imprecision and bias on both ASD structure and ASD performance. We additionally propose three distance measures to compare the structure of ASDs. The methodology is illustrated using a simple simulation study and a more complex but realistic case study on the Dutch Travel Survey. The proposed methodology can be applied to other ASD optimization problems. In our simulation study and case study, the ASD was fairly robust to imprecision, but not to realistic dynamics in the design parameters. To deal with the sensitivity of ASDs to changing design parameters, we recommend to learn and update the design parameters.

  2. Which sociodemographic factors are important on smoking behaviour of high school students? The contribution of classification and regression tree methodology in a broad epidemiological survey.

    Science.gov (United States)

    Ozge, C; Toros, F; Bayramkaya, E; Camdeviren, H; Sasmaz, T

    2006-08-01

    The purpose of this study is to evaluate the most important sociodemographic factors on smoking status of high school students using a broad randomised epidemiological survey. Using in-class, self administered questionnaire about their sociodemographic variables and smoking behaviour, a representative sample of total 3304 students of preparatory, 9th, 10th, and 11th grades, from 22 randomly selected schools of Mersin, were evaluated and discriminative factors have been determined using appropriate statistics. In addition to binary logistic regression analysis, the study evaluated combined effects of these factors using classification and regression tree methodology, as a new statistical method. The data showed that 38% of the students reported lifetime smoking and 16.9% of them reported current smoking with a male predominancy and increasing prevalence by age. Second hand smoking was reported at a 74.3% frequency with father predominance (56.6%). The significantly important factors that affect current smoking in these age groups were increased by household size, late birth rank, certain school types, low academic performance, increased second hand smoking, and stress (especially reported as separation from a close friend or because of violence at home). Classification and regression tree methodology showed the importance of some neglected sociodemographic factors with a good classification capacity. It was concluded that, as closely related with sociocultural factors, smoking was a common problem in this young population, generating important academic and social burden in youth life and with increasing data about this behaviour and using new statistical methods, effective coping strategies could be composed.

  3. How Big of a Problem is Analytic Error in Secondary Analyses of Survey Data?

    Directory of Open Access Journals (Sweden)

    Brady T West

    Full Text Available Secondary analyses of survey data collected from large probability samples of persons or establishments further scientific progress in many fields. The complex design features of these samples improve data collection efficiency, but also require analysts to account for these features when conducting analysis. Unfortunately, many secondary analysts from fields outside of statistics, biostatistics, and survey methodology do not have adequate training in this area, and as a result may apply incorrect statistical methods when analyzing these survey data sets. This in turn could lead to the publication of incorrect inferences based on the survey data that effectively negate the resources dedicated to these surveys. In this article, we build on the results of a preliminary meta-analysis of 100 peer-reviewed journal articles presenting analyses of data from a variety of national health surveys, which suggested that analytic errors may be extremely prevalent in these types of investigations. We first perform a meta-analysis of a stratified random sample of 145 additional research products analyzing survey data from the Scientists and Engineers Statistical Data System (SESTAT, which describes features of the U.S. Science and Engineering workforce, and examine trends in the prevalence of analytic error across the decades used to stratify the sample. We once again find that analytic errors appear to be quite prevalent in these studies. Next, we present several example analyses of real SESTAT data, and demonstrate that a failure to perform these analyses correctly can result in substantially biased estimates with standard errors that do not adequately reflect complex sample design features. Collectively, the results of this investigation suggest that reviewers of this type of research need to pay much closer attention to the analytic methods employed by researchers attempting to publish or present secondary analyses of survey data.

  4. How Big of a Problem is Analytic Error in Secondary Analyses of Survey Data?

    Science.gov (United States)

    West, Brady T.; Sakshaug, Joseph W.; Aurelien, Guy Alain S.

    2016-01-01

    Secondary analyses of survey data collected from large probability samples of persons or establishments further scientific progress in many fields. The complex design features of these samples improve data collection efficiency, but also require analysts to account for these features when conducting analysis. Unfortunately, many secondary analysts from fields outside of statistics, biostatistics, and survey methodology do not have adequate training in this area, and as a result may apply incorrect statistical methods when analyzing these survey data sets. This in turn could lead to the publication of incorrect inferences based on the survey data that effectively negate the resources dedicated to these surveys. In this article, we build on the results of a preliminary meta-analysis of 100 peer-reviewed journal articles presenting analyses of data from a variety of national health surveys, which suggested that analytic errors may be extremely prevalent in these types of investigations. We first perform a meta-analysis of a stratified random sample of 145 additional research products analyzing survey data from the Scientists and Engineers Statistical Data System (SESTAT), which describes features of the U.S. Science and Engineering workforce, and examine trends in the prevalence of analytic error across the decades used to stratify the sample. We once again find that analytic errors appear to be quite prevalent in these studies. Next, we present several example analyses of real SESTAT data, and demonstrate that a failure to perform these analyses correctly can result in substantially biased estimates with standard errors that do not adequately reflect complex sample design features. Collectively, the results of this investigation suggest that reviewers of this type of research need to pay much closer attention to the analytic methods employed by researchers attempting to publish or present secondary analyses of survey data. PMID:27355817

  5. Toward decentralized analysis of mercury (II) in real samples. A critical review on nanotechnology-based methodologies

    International Nuclear Information System (INIS)

    Botasini, Santiago; Heijo, Gonzalo; Méndez, Eduardo

    2013-01-01

    Graphical abstract: -- Highlights: •Several methods based on nanotechnology achieve limit of detections in the pM and nM ranges for mercury (II) analysis. •Most of these methods are validated in filtered water samples and/or spiked samples. •Thiols in real samples constitute an actual competence for any sensor based on the binding of mercury (II) ions. •Future research should include the study of matrix interferences including thiols and dissolved organic matter. -- Abstract: In recent years, it has increased the number of works focused on the development of novel nanoparticle-based sensors for mercury detection, mainly motivated by the need of low cost portable devices capable of giving fast and reliable analytical response, thus contributing to the analytical decentralization. Methodologies employing colorimetric, fluorometric, magnetic, and electrochemical output signals allowed reaching detection limits within the pM and nM ranges. Most of these developments proved their suitability in detecting and quantifying mercury (II) ions in synthetic solutions or spiked water samples. However, the state of art in these technologies is still behind the standard methods of mercury quantification, such as cold vapor atomic absorption spectrometry and inductively coupled plasma techniques, in terms of reliability and sensitivity. This is mainly because the response of nanoparticle-based sensors is highly affected by the sample matrix. The developed analytical nanosystems may fail in real samples because of the negative incidence of the ionic strength and the presence of exchangeable ligands. The aim of this review is to critically consider the recently published innovations in this area, and highlight the needs to include more realistic assays in future research in order to make these advances suitable for on-site analysis

  6. Comparison of Health Examination Survey Methods in Brazil, Chile, Colombia, Mexico, England, Scotland, and the United States.

    Science.gov (United States)

    Mindell, Jennifer S; Moody, Alison; Vecino-Ortiz, Andres I; Alfaro, Tania; Frenz, Patricia; Scholes, Shaun; Gonzalez, Silvia A; Margozzini, Paula; de Oliveira, Cesar; Sanchez Romero, Luz Maria; Alvarado, Andres; Cabrera, Sebastián; Sarmiento, Olga L; Triana, Camilo A; Barquera, Simón

    2017-09-15

    Comparability of population surveys across countries is key to appraising trends in population health. Achieving this requires deep understanding of the methods used in these surveys to examine the extent to which the measurements are comparable. In this study, we obtained detailed protocols of 8 nationally representative surveys from 2007-2013 from Brazil, Chile, Colombia, Mexico, the United Kingdom (England and Scotland), and the United States-countries that that differ in economic and inequity indicators. Data were collected on sampling frame, sample selection procedures, recruitment, data collection methods, content of interview and examination modules, and measurement protocols. We also assessed their adherence to the World Health Organization's "STEPwise Approach to Surveillance" framework for population health surveys. The surveys, which included half a million participants, were highly comparable on sampling methodology, survey questions, and anthropometric measurements. Heterogeneity was found for physical activity questionnaires and biological samples collection. The common age range included by the surveys was adults aged 18-64 years. The methods used in these surveys were similar enough to enable comparative analyses of the data across the 7 countries. This comparability is crucial in assessing and comparing national and subgroup population health, and to assisting the transfer of research and policy knowledge across countries. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. UAV-Based Photogrammetry and Integrated Technologies for Architectural Applications—Methodological Strategies for the After-Quake Survey of Vertical Structures in Mantua (Italy

    Directory of Open Access Journals (Sweden)

    Cristiana Achille

    2015-06-01

    Full Text Available This paper examines the survey of tall buildings in an emergency context like in the case of post-seismic events. The after-earthquake survey has to guarantee time-savings, high precision and security during the operational stages. The main goal is to optimize the application of methodologies based on acquisition and automatic elaborations of photogrammetric data even with the use of Unmanned Aerial Vehicle (UAV systems in order to provide fast and low cost operations. The suggested methods integrate new technologies with commonly used technologies like TLS and topographic acquisition. The value of the photogrammetric application is demonstrated by a test case, based on the comparison of acquisition, calibration and 3D modeling results in case of use of a laser scanner, metric camera and amateur reflex camera. The test would help us to demonstrate the efficiency of image based methods in the acquisition of complex architecture. The case study is Santa Barbara Bell tower in Mantua. The applied survey solution allows a complete 3D database of the complex architectural structure to be obtained for the extraction of all the information needed for significant intervention. This demonstrates the applicability of the photogrammetry using UAV for the survey of vertical structures, complex buildings and difficult accessible architectural parts, providing high precision results.

  8. UAV-Based Photogrammetry and Integrated Technologies for Architectural Applications—Methodological Strategies for the After-Quake Survey of Vertical Structures in Mantua (Italy)

    Science.gov (United States)

    Achille, Cristiana; Adami, Andrea; Chiarini, Silvia; Cremonesi, Stefano; Fassi, Francesco; Fregonese, Luigi; Taffurelli, Laura

    2015-01-01

    This paper examines the survey of tall buildings in an emergency context like in the case of post-seismic events. The after-earthquake survey has to guarantee time-savings, high precision and security during the operational stages. The main goal is to optimize the application of methodologies based on acquisition and automatic elaborations of photogrammetric data even with the use of Unmanned Aerial Vehicle (UAV) systems in order to provide fast and low cost operations. The suggested methods integrate new technologies with commonly used technologies like TLS and topographic acquisition. The value of the photogrammetric application is demonstrated by a test case, based on the comparison of acquisition, calibration and 3D modeling results in case of use of a laser scanner, metric camera and amateur reflex camera. The test would help us to demonstrate the efficiency of image based methods in the acquisition of complex architecture. The case study is Santa Barbara Bell tower in Mantua. The applied survey solution allows a complete 3D database of the complex architectural structure to be obtained for the extraction of all the information needed for significant intervention. This demonstrates the applicability of the photogrammetry using UAV for the survey of vertical structures, complex buildings and difficult accessible architectural parts, providing high precision results. PMID:26134108

  9. UAV-Based Photogrammetry and Integrated Technologies for Architectural Applications--Methodological Strategies for the After-Quake Survey of Vertical Structures in Mantua (Italy).

    Science.gov (United States)

    Achille, Cristiana; Adami, Andrea; Chiarini, Silvia; Cremonesi, Stefano; Fassi, Francesco; Fregonese, Luigi; Taffurelli, Laura

    2015-06-30

    This paper examines the survey of tall buildings in an emergency context like in the case of post-seismic events. The after-earthquake survey has to guarantee time-savings, high precision and security during the operational stages. The main goal is to optimize the application of methodologies based on acquisition and automatic elaborations of photogrammetric data even with the use of Unmanned Aerial Vehicle (UAV) systems in order to provide fast and low cost operations. The suggested methods integrate new technologies with commonly used technologies like TLS and topographic acquisition. The value of the photogrammetric application is demonstrated by a test case, based on the comparison of acquisition, calibration and 3D modeling results in case of use of a laser scanner, metric camera and amateur reflex camera. The test would help us to demonstrate the efficiency of image based methods in the acquisition of complex architecture. The case study is Santa Barbara Bell tower in Mantua. The applied survey solution allows a complete 3D database of the complex architectural structure to be obtained for the extraction of all the information needed for significant intervention. This demonstrates the applicability of the photogrammetry using UAV for the survey of vertical structures, complex buildings and difficult accessible architectural parts, providing high precision results.

  10. Amostra mestra e geoprocessamento: tecnologias para inquéritos domiciliares Master sample and geoprocessing: technologies for household surveys

    Directory of Open Access Journals (Sweden)

    Nilza Nunes da Silva

    2003-08-01

    census enumeration areas in several epidemiological surveys using updated information from the National Survey of Households (PNAD. METHODS: Address data file comprising 72 census enumeration areas was kept as primary sampling units for the city of São Paulo. During the period 1995-2000, three distinct household samples were drawn using the two-stage cluster sampling procedure. Geographic Information System (GIS technology allowed delimiting boundaries, blocks and streets for any primary sampling unit and printing updated maps for selected sub-samples. RESULTS: Twenty-five thousand dwellings made up the permanent address data file of the master sample. A cheaper and quicker selection of each sample, plus gathering information on demographic and topographical profiles of census enumeration areas were the main contribution of the study results. CONCLUSIONS: The master sample concept, integrated with GIS technology, is an advantageous alternative sampling design for household surveys in urban areas. Using the list of addresses from the PNAD updated yearly, although limiting its application to the most populated Brazilian cities, avoids the need of creating an independent sampling procedure for each individual survey carried out in the period between demographic censuses, and it is an important contribution for planning sampling surveys in public health.

  11. 200-UP-2 operable unit radiological surveys

    International Nuclear Information System (INIS)

    Wendling, M.A.

    1994-01-01

    This report summarizes and documents the results of the radiological surveys conducted from August 17 through December 16, 1993 over a partial area of the 200-UP-2 Operable Unit, 200-W Area, Hanford Site, Richland, Washington. In addition, this report explains the survey methodology of the Mobile Surface Contamination Monitor 11 (MSCM-II) and the Ultra Sonic Ranging And Data System (USRADS). The radiological survey of the 200-UP-2 Operable Unit was conducted by the Site Investigative Surveys/Environmental Restoration Health Physics Organization of the Westinghouse Hanford Company. The survey methodology for the majority of area was based on utilization of the MSCM-II or the USRADS for automated recording of the gross beta/gamma radiation levels at or near six (6) inches from the surface soil

  12. Optimum sample size to estimate mean parasite abundance in fish parasite surveys

    Directory of Open Access Journals (Sweden)

    Shvydka S.

    2018-03-01

    Full Text Available To reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined precision level and parameter of the negative binomial distribution estimated from the empirical data. A simulation approach to optimum sample size determination aimed at the estimation of true value of the mean abundance and its confidence interval (CI was based on the Bag of Little Bootstraps (BLB. The abundance of two species of monogenean parasites Ligophorus cephali and L. mediterraneus from Mugil cephalus across the Azov-Black Seas localities were subjected to the analysis. The dispersion pattern of both helminth species could be characterized as a highly aggregated distribution with the variance being substantially larger than the mean abundance. The holistic approach applied here offers a wide range of appropriate methods in searching for the optimum sample size and the understanding about the expected precision level of the mean. Given the superior performance of the BLB relative to formulae with its few assumptions, the bootstrap procedure is the preferred method. Two important assessments were performed in the present study: i based on CIs width a reasonable precision level for the mean abundance in parasitological surveys of Ligophorus spp. could be chosen between 0.8 and 0.5 with 1.6 and 1x mean of the CIs width, and ii the sample size equal 80 or more host individuals allows accurate and precise estimation of mean abundance. Meanwhile for the host sample size in range between 25 and 40 individuals, the median estimates showed minimal bias but the sampling distribution skewed to the low values; a sample size of 10 host individuals yielded to unreliable estimates.

  13. Optimal sampling schemes applied in geology

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2010-05-01

    Full Text Available Methodology 6 Results 7 Background and Research Question for Study 2 8 Study Area and Data 9 Methodology 10 Results 11 Conclusions Debba (CSIR) Optimal Sampling Schemes applied in Geology UP 2010 2 / 47 Outline 1 Introduction to hyperspectral remote... sensing 2 Objective of Study 1 3 Study Area 4 Data used 5 Methodology 6 Results 7 Background and Research Question for Study 2 8 Study Area and Data 9 Methodology 10 Results 11 Conclusions Debba (CSIR) Optimal Sampling Schemes applied in Geology...

  14. A Quantitative, Non-Destructive Methodology for Habitat Characterisation and Benthic Monitoring at Offshore Renewable Energy Developments

    Science.gov (United States)

    Sheehan, Emma V.; Stevens, Timothy F.; Attrill, Martin J.

    2010-01-01

    Following governments' policies to tackle global climate change, the development of offshore renewable energy sites is likely to increase substantially over coming years. All such developments interact with the seabed to some degree and so a key need exists for suitable methodology to monitor the impacts of large-scale Marine Renewable Energy Installations (MREIs). Many of these will be situated on mixed or rocky substrata, where conventional methods to characterise the habitat are unsuitable. Traditional destructive sampling is also inappropriate in conservation terms, particularly as safety zones around (MREIs) could function as Marine Protected Areas, with positive benefits for biodiversity. Here we describe a technique developed to effectively monitor the impact of MREIs and report the results of its field testing, enabling large areas to be surveyed accurately and cost-effectively. The methodology is based on a high-definition video camera, plus LED lights and laser scale markers, mounted on a “flying array” that maintains itself above the seabed grounded by a length of chain, thus causing minimal damage. Samples are taken by slow-speed tows of the gear behind a boat (200 m transects). The HD video and randomly selected frame grabs are analysed to quantify species distribution. The equipment was tested over two years in Lyme Bay, UK (25 m depth), then subsequently successfully deployed in demanding conditions at the deep (>50 m) high-energy Wave Hub site off Cornwall, UK, and a potential tidal stream energy site in Guernsey, Channel Islands (1.5 ms−1 current), the first time remote samples from such a habitat have been achieved. The next stage in the monitoring development process is described, involving the use of Remote Operated Vehicles to survey the seabed post-deployment of MREI devices. The complete methodology provides the first quantitative, relatively non-destructive method for monitoring mixed-substrate benthic communities beneath MPAs and

  15. A quantitative, non-destructive methodology for habitat characterisation and benthic monitoring at offshore renewable energy developments.

    Directory of Open Access Journals (Sweden)

    Emma V Sheehan

    2010-12-01

    Full Text Available Following governments' policies to tackle global climate change, the development of offshore renewable energy sites is likely to increase substantially over coming years. All such developments interact with the seabed to some degree and so a key need exists for suitable methodology to monitor the impacts of large-scale Marine Renewable Energy Installations (MREIs. Many of these will be situated on mixed or rocky substrata, where conventional methods to characterise the habitat are unsuitable. Traditional destructive sampling is also inappropriate in conservation terms, particularly as safety zones around (MREIs could function as Marine Protected Areas, with positive benefits for biodiversity. Here we describe a technique developed to effectively monitor the impact of MREIs and report the results of its field testing, enabling large areas to be surveyed accurately and cost-effectively. The methodology is based on a high-definition video camera, plus LED lights and laser scale markers, mounted on a "flying array" that maintains itself above the seabed grounded by a length of chain, thus causing minimal damage. Samples are taken by slow-speed tows of the gear behind a boat (200 m transects. The HD video and randomly selected frame grabs are analysed to quantify species distribution. The equipment was tested over two years in Lyme Bay, UK (25 m depth, then subsequently successfully deployed in demanding conditions at the deep (>50 m high-energy Wave Hub site off Cornwall, UK, and a potential tidal stream energy site in Guernsey, Channel Islands (1.5 ms⁻¹ current, the first time remote samples from such a habitat have been achieved. The next stage in the monitoring development process is described, involving the use of Remote Operated Vehicles to survey the seabed post-deployment of MREI devices. The complete methodology provides the first quantitative, relatively non-destructive method for monitoring mixed-substrate benthic communities beneath

  16. A drink is a drink? Variation in the amount of alcohol contained in beer, wine and spirits drinks in a US methodological sample.

    Science.gov (United States)

    Kerr, William C; Greenfield, Thomas K; Tujague, Jennifer; Brown, Stephan E

    2005-11-01

    Empirically based estimates of the mean alcohol content of beer, wine and spirits drinks from a national sample of US drinkers are not currently available. A sample of 310 drinkers from the 2000 National Alcohol Survey were re-contacted to participate in a telephone survey with specific questions about the drinks they consume. Subjects were instructed to prepare their usual drink of each beverage at home and to measure each alcoholic beverage and other ingredients with a provided beaker. Information on the brand or type of each beverage was used to specify the percentage of alcohol. The weighted mean alcohol content of respondents' drinks was 0.67 ounces overall, 0.56 ounces for beer, 0.66 ounces for wine and 0.89 ounces for spirits. Spirits and wine drink contents were particularly variable with many high-alcohol drinks observed. While the 0.6-ounce of alcohol drink standard appears to be a reasonable single standard, it cannot capture the substantial variation evident in this sample and it underestimates average wine and spirits ethanol content. Direct measurement or beverage-specific mean ethanol content estimates would improve the precision of survey alcohol assessment.

  17. The Sloan Digital Sky Survey Quasar Lens Search. IV. Statistical Lens Sample from the Fifth Data Release

    Energy Technology Data Exchange (ETDEWEB)

    Inada, Naohisa; /Wako, RIKEN /Tokyo U., ICEPP; Oguri, Masamune; /Natl. Astron. Observ. of Japan /Stanford U., Phys. Dept.; Shin, Min-Su; /Michigan U. /Princeton U. Observ.; Kayo, Issha; /Tokyo U., ICRR; Strauss, Michael A.; /Princeton U. Observ.; Hennawi, Joseph F.; /UC, Berkeley /Heidelberg, Max Planck Inst. Astron.; Morokuma, Tomoki; /Natl. Astron. Observ. of Japan; Becker, Robert H.; /LLNL, Livermore /UC, Davis; White, Richard L.; /Baltimore, Space Telescope Sci.; Kochanek, Christopher S.; /Ohio State U.; Gregg, Michael D.; /LLNL, Livermore /UC, Davis /Exeter U.

    2010-05-01

    We present the second report of our systematic search for strongly lensed quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive follow-up observations of 136 candidate objects, we find 36 lenses in the full sample of 77,429 spectroscopically confirmed quasars in the SDSS Data Release 5. We then define a complete sample of 19 lenses, including 11 from our previous search in the SDSS Data Release 3, from the sample of 36,287 quasars with i < 19.1 in the redshift range 0.6 < z < 2.2, where we require the lenses to have image separations of 1 < {theta} < 20 and i-band magnitude differences between the two images smaller than 1.25 mag. Among the 19 lensed quasars, 3 have quadruple-image configurations, while the remaining 16 show double images. This lens sample constrains the cosmological constant to be {Omega}{sub {Lambda}} = 0.84{sub -0.08}{sup +0.06}(stat.){sub -0.07}{sup + 0.09}(syst.) assuming a flat universe, which is in good agreement with other cosmological observations. We also report the discoveries of 7 binary quasars with separations ranging from 1.1 to 16.6, which are identified in the course of our lens survey. This study concludes the construction of our statistical lens sample in the full SDSS-I data set.

  18. THE FMOS-COSMOS SURVEY OF STAR-FORMING GALAXIES AT z ∼ 1.6. III. SURVEY DESIGN, PERFORMANCE, AND SAMPLE CHARACTERISTICS

    Energy Technology Data Exchange (ETDEWEB)

    Silverman, J. D.; Sugiyama, N. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study, The University of Tokyo, Kashiwa, 277-8583 (Japan); Kashino, D. [Division of Particle and Astrophysical Science, Graduate School of Science, Nagoya University, Nagoya, 464-8602 (Japan); Sanders, D.; Zahid, J.; Kewley, L. J.; Chu, J.; Hasinger, G. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI, 96822 (United States); Kartaltepe, J. S. [National Optical Astronomy Observatory, 950 N. Cherry Ave., Tucson, AZ, 85719 (United States); Arimoto, N. [Subaru Telescope, 650 North A’ohoku Place, Hilo, Hawaii, 96720 (United States); Renzini, A. [Instituto Nazionale de Astrofisica, Osservatorio Astronomico di Padova, vicolo dell’Osservatorio 5, I-35122, Padova, Italy, EU (Italy); Rodighiero, G.; Baronchelli, I. [Dipartimento di Fisica e Astronomia, Universita di Padova, vicolo Osservatorio, 3, I-35122, Padova (Italy); Daddi, E.; Juneau, S. [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d’Astrophysique, CEA Saclay (France); Nagao, T. [Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Lilly, S. J.; Carollo, C. M. [Institute of Astronomy, ETH Zürich, CH-8093, Zürich (Switzerland); Capak, P. [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Ilbert, O., E-mail: john.silverman@ipmu.jp [Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388, Marseille (France); and others

    2015-09-15

    We present a spectroscopic survey of galaxies in the COSMOS field using the Fiber Multi-object Spectrograph (FMOS), a near-infrared instrument on the Subaru Telescope. Our survey is specifically designed to detect the Hα emission line that falls within the H-band (1.6–1.8 μm) spectroscopic window from star-forming galaxies with 1.4 < z < 1.7 and M{sub stellar} ≳ 10{sup 10} M{sub ⊙}. With the high multiplex capability of FMOS, it is now feasible to construct samples of over 1000 galaxies having spectroscopic redshifts at epochs that were previously challenging. The high-resolution mode (R ∼ 2600) effectively separates Hα and [N ii]λ6585, thus enabling studies of the gas-phase metallicity and photoionization state of the interstellar medium. The primary aim of our program is to establish how star formation depends on stellar mass and environment, both recognized as drivers of galaxy evolution at lower redshifts. In addition to the main galaxy sample, our target selection places priority on those detected in the far-infrared by Herschel/PACS to assess the level of obscured star formation and investigate, in detail, outliers from the star formation rate (SFR)—stellar mass relation. Galaxies with Hα detections are followed up with FMOS observations at shorter wavelengths using the J-long (1.11–1.35 μm) grating to detect Hβ and [O iii]λ5008 which provides an assessment of the extinction required to measure SFRs not hampered by dust, and an indication of embedded active galactic nuclei. With 460 redshifts measured from 1153 spectra, we assess the performance of the instrument with respect to achieving our goals, discuss inherent biases in the sample, and detail the emission-line properties. Our higher-level data products, including catalogs and spectra, are available to the community.

  19. Manual for the Portable Handheld Neutron Counter (PHNC) for Neutron Survey and the Measurement of Plutonium Samples

    International Nuclear Information System (INIS)

    Menlove, H.O.

    2005-01-01

    We have designed a portable neutron detector for passive neutron scanning measurement and coincidence counting of bulk samples of plutonium. The counter will be used for neutron survey applications as well as the measurement of plutonium samples for portable applications. The detector uses advanced design 3 He tubes to increase the efficiency and battery operated shift register electronics. This report describes the hardware, performance, and calibration for the system

  20. Assessment of frequency and duration of point counts when surveying for golden eagle presence

    Science.gov (United States)

    Skipper, Ben R.; Boal, Clint W.; Tsai, Jo-Szu; Fuller, Mark R.

    2017-01-01

    We assessed the utility of the recommended golden eagle (Aquila chrysaetos) survey methodology in the U.S. Fish and Wildlife Service 2013 Eagle Conservation Plan Guidance. We conducted 800-m radius, 1-hr point-count surveys broken into 20-min segments, during 2 sampling periods in 3 areas within the Intermountain West of the United States over 2 consecutive breeding seasons during 2012 and 2013. Our goal was to measure the influence of different survey time intervals and sampling periods on detectability and use estimates of golden eagles among different locations. Our results suggest that a less intensive effort (i.e., survey duration shorter than 1 hr and point-count survey radii smaller than 800 m) would likely be inadequate for rigorous documentation of golden eagle occurrence pre- or postconstruction of wind energy facilities. Results from a simulation analysis of detection probabilities and survey effort suggest that greater temporal and spatial effort could make point-count surveys more applicable for evaluating golden eagle occurrence in survey areas; however, increased effort would increase financial costs associated with additional person-hours and logistics (e.g., fuel, lodging). Future surveys can benefit from a pilot study and careful consideration of prior information about counts or densities of golden eagles in the survey area before developing a survey design. If information is lacking, survey planning may be best served by assuming low detection rates and increasing the temporal and spatial effort.

  1. Gotta survey somebody : Methodological challenges in population studies of older people

    OpenAIRE

    Kelfve, Susanne

    2015-01-01

    Conducting representative surveys of older people is challenging. This thesis aims to analyze a) the characteristics of individuals at risk of being underrepresented in surveys of older people, b) the systematic errors likely to occur as a result of these selections, and c) whether these systematic errors can be minimized by weighting adjustments.   In Study I, we investigated a) who would be missing from a survey that excluded those living in institutions and that did not use indirect interv...

  2. Measurement of environmental impacts of telework adoption amidst change in complex organizations. AT and T survey methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Atkyns, Robert; Blazek, Michele; Roitz, Joseph [AT and T, 179 Bothin Road, 94930 Fairfax, CA (United States)

    2002-10-01

    Telecommuting practices and their environmental and organizational performance impacts have stimulated research across academic disciplines. Although telecommuting trends and impact projections are reported, few true longitudinal studies involving large organizations have been conducted. Published studies typically lack the research design elements to control a major confounding variable: rapid and widespread organizational change. Yet social science 'Best Practices' and market research industry quality control procedures exist that can help manage organizational change effects and other common sources of measurement error. In 1992, AT and T established a formal, corporate-wide telecommuting policy. A research and statistical modeling initiative was implemented to measure how flexible work arrangements reduce automotive emissions. Annual employee surveys were begun in 1994. As telecommuting benefits have been increasingly recognized within AT and T, the essential construct has been redefined as 'telework.' The survey's scope has expanded to address broader organization issues and provide guidance to multiple internal constituencies. This paper focuses upon the procedures used to reliably measure the adoption of telework practices and model their environmental impact, and contrasts those procedures with other, less reliable methodologies.

  3. Conducting Web-based Surveys.

    OpenAIRE

    David J. Solomon

    2001-01-01

    Web-based surveying is becoming widely used in social science and educational research. The Web offers significant advantages over more traditional survey techniques however there are still serious methodological challenges with using this approach. Currently coverage bias or the fact significant numbers of people do not have access, or choose not to use the Internet is of most concern to researchers. Survey researchers also have much to learn concerning the most effective ways to conduct s...

  4. Data Processing Procedures and Methodology for Estimating Trip Distances for the 1995 American Travel Survey (ATS)

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, H.-L.; Rollow, J.

    2000-05-01

    The 1995 American Travel Survey (ATS) collected information from approximately 80,000 U.S. households about their long distance travel (one-way trips of 100 miles or more) during the year of 1995. It is the most comprehensive survey of where, why, and how U.S. residents travel since 1977. ATS is a joint effort by the U.S. Department of Transportation (DOT) Bureau of Transportation Statistics (BTS) and the U.S. Department of Commerce Bureau of Census (Census); BTS provided the funding and supervision of the project, and Census selected the samples, conducted interviews, and processed the data. This report documents the technical support for the ATS provided by the Center for Transportation Analysis (CTA) in Oak Ridge National Laboratory (ORNL), which included the estimation of trip distances as well as data quality editing and checking of variables required for the distance calculations.

  5. Using Electronic Surveys: Advice from Survey Professionals.

    Directory of Open Access Journals (Sweden)

    David M. Shannon

    2002-01-01

    Full Text Available The study reports the perceptions and recommendations of sixty-two experienced survey..researchers from the American Educational Research Association regarding the use of..electronic surveys. The most positive aspects cited for the use of electronic surveys were..reduction of costs (i.e., postage, phone charges, the use of electronic mail for pre-notification or..follow-up purposes, and the compatibility of data with existing software programs. These..professionals expressed limitations in using electronic surveys pertaining to the limited..sampling frame as well as issues of confidentiality, privacy, and the credibility of the sample...They advised that electronic surveys designed with the varied technological background and..capabilities of the respondent in mind, follow sound principles of survey construction, and be..administered to pre-notified, targeted populations with published email addresses.

  6. Dark Energy Survey Year 1 Results: Galaxy Sample for BAO Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Crocce, M.; et al.

    2017-12-17

    We define and characterise a sample of 1.3 million galaxies extracted from the first year of Dark Energy Survey data, optimised to measure Baryon Acoustic Oscillations in the presence of significant redshift uncertainties. The sample is dominated by luminous red galaxies located at redshifts $z \\gtrsim 0.6$. We define the exact selection using color and magnitude cuts that balance the need of high number densities and small photometric redshift uncertainties, using the corresponding forecasted BAO distance error as a figure-of-merit in the process. The typical photo-$z$ uncertainty varies from $2.3\\%$ to $3.6\\%$ (in units of 1+$z$) from $z=0.6$ to $1$, with number densities from $200$ to $130$ galaxies per deg$^2$ in tomographic bins of width $\\Delta z = 0.1$. Next we summarise the validation of the photometric redshift estimation. We characterise and mitigate observational systematics including stellar contamination, and show that the clustering on large scales is robust in front of those contaminants. We show that the clustering signal in the auto-correlations and cross-correlations is generally consistent with theoretical models, which serves as an additional test of the redshift distributions.

  7. Using the Superpopulation Model for Imputations and Variance Computation in Survey Sampling

    Directory of Open Access Journals (Sweden)

    Petr Novák

    2012-03-01

    Full Text Available This study is aimed at variance computation techniques for estimates of population characteristics based on survey sampling and imputation. We use the superpopulation regression model, which means that the target variable values for each statistical unit are treated as random realizations of a linear regression model with weighted variance. We focus on regression models with one auxiliary variable and no intercept, which have many applications and straightforward interpretation in business statistics. Furthermore, we deal with caseswhere the estimates are not independent and thus the covariance must be computed. We also consider chained regression models with auxiliary variables as random variables instead of constants.

  8. The importance of sound methodology in environmental DNA sampling

    Science.gov (United States)

    T. M. Wilcox; K. J. Carim; M. K. Young; K. S. McKelvey; T. W. Franklin; M. K. Schwartz

    2018-01-01

    Environmental DNA (eDNA) sampling - which enables inferences of species’ presence from genetic material in the environment - is a powerful tool for sampling rare fishes. Numerous studies have demonstrated that eDNA sampling generally provides greater probabilities of detection than traditional techniques (e.g., Thomsen et al. 2012; McKelvey et al. 2016; Valentini et al...

  9. Using lot quality-assurance sampling and area sampling to identify priority areas for trachoma control: Viet Nam.

    Science.gov (United States)

    Myatt, Mark; Mai, Nguyen Phuong; Quynh, Nguyen Quang; Nga, Nguyen Huy; Tai, Ha Huy; Long, Nguyen Hung; Minh, Tran Hung; Limburg, Hans

    2005-10-01

    To report on the use of lot quality-assurance sampling (LQAS) surveys undertaken within an area-sampling framework to identify priority areas for intervention with trachoma control activities in Viet Nam. The LQAS survey method for the rapid assessment of the prevalence of active trachoma was adapted for use in Viet Nam with the aim of classifying individual communes by the prevalence of active trachoma among children in primary school. School-based sampling was used; school sites to be sampled were selected using an area-sampling approach. A total of 719 communes in 41 districts in 18 provinces were surveyed. Survey staff found the LQAS survey method both simple and rapid to use after initial problems with area-sampling methods were identified and remedied. The method yielded a finer spatial resolution of prevalence than had been previously achieved in Viet Nam using semiquantitative rapid assessment surveys and multistage cluster-sampled surveys. When used with area-sampling techniques, the LQAS survey method has the potential to form the basis of survey instruments that can be used to efficiently target resources for interventions against active trachoma. With additional work, such methods could provide a generally applicable tool for effective programme planning and for the certification of the elimination of trachoma as a blinding disease.

  10. Statistical searches for microlensing events in large, non-uniformly sampled time-domain surveys: A test using palomar transient factory data

    Energy Technology Data Exchange (ETDEWEB)

    Price-Whelan, Adrian M.; Agüeros, Marcel A. [Department of Astronomy, Columbia University, 550 W 120th Street, New York, NY 10027 (United States); Fournier, Amanda P. [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106 (United States); Street, Rachel [Las Cumbres Observatory Global Telescope Network, Inc., 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Ofek, Eran O. [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Covey, Kevin R. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Levitan, David; Sesar, Branimir [Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Laher, Russ R.; Surace, Jason, E-mail: adrn@astro.columbia.edu [Spitzer Science Center, California Institute of Technology, Mail Stop 314-6, Pasadena, CA 91125 (United States)

    2014-01-20

    Many photometric time-domain surveys are driven by specific goals, such as searches for supernovae or transiting exoplanets, which set the cadence with which fields are re-imaged. In the case of the Palomar Transient Factory (PTF), several sub-surveys are conducted in parallel, leading to non-uniform sampling over its ∼20,000 deg{sup 2} footprint. While the median 7.26 deg{sup 2} PTF field has been imaged ∼40 times in the R band, ∼2300 deg{sup 2} have been observed >100 times. We use PTF data to study the trade off between searching for microlensing events in a survey whose footprint is much larger than that of typical microlensing searches, but with far-from-optimal time sampling. To examine the probability that microlensing events can be recovered in these data, we test statistics used on uniformly sampled data to identify variables and transients. We find that the von Neumann ratio performs best for identifying simulated microlensing events in our data. We develop a selection method using this statistic and apply it to data from fields with >10 R-band observations, 1.1 × 10{sup 9} light curves, uncovering three candidate microlensing events. We lack simultaneous, multi-color photometry to confirm these as microlensing events. However, their number is consistent with predictions for the event rate in the PTF footprint over the survey's three years of operations, as estimated from near-field microlensing models. This work can help constrain all-sky event rate predictions and tests microlensing signal recovery in large data sets, which will be useful to future time-domain surveys, such as that planned with the Large Synoptic Survey Telescope.

  11. Evaluating telephone follow-up of a mail survey of community pharmacies.

    Science.gov (United States)

    Westrick, Salisa C; Mount, Jeanine K

    2007-06-01

    Mail and telephone are commonly used modes of survey with pharmacists. Research conducted using general population surveys consistently describes mail surveys as being less expensive but yielding lower response rates than telephone surveys. However, findings obtained from the general population may not be generalizable to pharmacist surveys. This study evaluates the effectiveness of telephone follow-up of mail survey nonrespondents by comparing the 2 survey modes on response rates, cooperation rates, cost per sample unit, and cost per usable response and evaluating potential nonresponse bias in the context of immunization activities. A census mail survey of 1,143 Washington State community pharmacies and a follow-up telephone survey of 262 randomly selected mail survey nonrespondents were compared. Both surveys included the same 15 yes/no-type questions to ask respondents about their pharmacy's involvement in immunization activities. The mail survey yielded a response rate 1 of 26.7% and a cooperation rate 1 of 26.7%, compared with 83.6% and 87.8%, respectively, for the follow-up telephone survey. With respect to cost per sample unit, the mail survey was the least expensive option ($1.20). However, when comparing cost per usable response, the mail survey was the most expensive ($4.37), and the follow-up telephone survey without an advance notification was the least expensive ($1.99). Furthermore, results suggest the presence of nonresponse bias: compared with pharmacies participating in the follow-up telephone survey, pharmacies participating in the mail survey were more likely to be involved in in-house immunization services but less likely to be involved in outsourced services. The telephone survey achieved higher outcome rates with reduced cost per usable response. A telephone survey is a viable mode that holds promise in pharmacy practice research. Maximizing response rates and assessing potential nonresponse bias should be a standard practice among pharmacy

  12. Lessons Learned from the Administration of a Web-Based Survey.

    Science.gov (United States)

    Mertler, Craig A.

    This paper describes the methodology used in a research study involving the collection of data through a Web-based survey, focusing on the advantages and limitations of the methodology. The Teacher motivation and Job Satisfaction Survey was administered to K-12 teachers. Many of the difficulties occurred during the planning phase, as opposed to…

  13. A survey of decision tree classifier methodology

    Science.gov (United States)

    Safavian, S. R.; Landgrebe, David

    1991-01-01

    Decision tree classifiers (DTCs) are used successfully in many diverse areas such as radar signal classification, character recognition, remote sensing, medical diagnosis, expert systems, and speech recognition. Perhaps the most important feature of DTCs is their capability to break down a complex decision-making process into a collection of simpler decisions, thus providing a solution which is often easier to interpret. A survey of current methods is presented for DTC designs and the various existing issues. After considering potential advantages of DTCs over single-state classifiers, subjects of tree structure design, feature selection at each internal node, and decision and search strategies are discussed.

  14. Statistical properties of mean stand biomass estimators in a LIDAR-based double sampling forest survey design.

    Science.gov (United States)

    H.E. Anderson; J. Breidenbach

    2007-01-01

    Airborne laser scanning (LIDAR) can be a valuable tool in double-sampling forest survey designs. LIDAR-derived forest structure metrics are often highly correlated with important forest inventory variables, such as mean stand biomass, and LIDAR-based synthetic regression estimators have the potential to be highly efficient compared to single-stage estimators, which...

  15. An evaluation of the quality of statistical design and analysis of published medical research: results from a systematic survey of general orthopaedic journals.

    Science.gov (United States)

    Parsons, Nick R; Price, Charlotte L; Hiskens, Richard; Achten, Juul; Costa, Matthew L

    2012-04-25

    The application of statistics in reported research in trauma and orthopaedic surgery has become ever more important and complex. Despite the extensive use of statistical analysis, it is still a subject which is often not conceptually well understood, resulting in clear methodological flaws and inadequate reporting in many papers. A detailed statistical survey sampled 100 representative orthopaedic papers using a validated questionnaire that assessed the quality of the trial design and statistical analysis methods. The survey found evidence of failings in study design, statistical methodology and presentation of the results. Overall, in 17% (95% confidence interval; 10-26%) of the studies investigated the conclusions were not clearly justified by the results, in 39% (30-49%) of studies a different analysis should have been undertaken and in 17% (10-26%) a different analysis could have made a difference to the overall conclusions. It is only by an improved dialogue between statistician, clinician, reviewer and journal editor that the failings in design methodology and analysis highlighted by this survey can be addressed.

  16. An evaluation of the quality of statistical design and analysis of published medical research: results from a systematic survey of general orthopaedic journals

    Directory of Open Access Journals (Sweden)

    Parsons Nick R

    2012-04-01

    Full Text Available Abstract Background The application of statistics in reported research in trauma and orthopaedic surgery has become ever more important and complex. Despite the extensive use of statistical analysis, it is still a subject which is often not conceptually well understood, resulting in clear methodological flaws and inadequate reporting in many papers. Methods A detailed statistical survey sampled 100 representative orthopaedic papers using a validated questionnaire that assessed the quality of the trial design and statistical analysis methods. Results The survey found evidence of failings in study design, statistical methodology and presentation of the results. Overall, in 17% (95% confidence interval; 10–26% of the studies investigated the conclusions were not clearly justified by the results, in 39% (30–49% of studies a different analysis should have been undertaken and in 17% (10–26% a different analysis could have made a difference to the overall conclusions. Conclusion It is only by an improved dialogue between statistician, clinician, reviewer and journal editor that the failings in design methodology and analysis highlighted by this survey can be addressed.

  17. Understanding palliative care on the heart failure care team: an innovative research methodology.

    Science.gov (United States)

    Lingard, Lorelei A; McDougall, Allan; Schulz, Valerie; Shadd, Joshua; Marshall, Denise; Strachan, Patricia H; Tait, Glendon R; Arnold, J Malcolm; Kimel, Gil

    2013-05-01

    There is a growing call to integrate palliative care for patients with advanced heart failure (HF). However, the knowledge to inform integration efforts comes largely from interview and survey research with individual patients and providers. This work has been critically important in raising awareness of the need for integration, but it is insufficient to inform solutions that must be enacted not by isolated individuals but by complex care teams. Research methods are urgently required to support systematic exploration of the experiences of patients with HF, family caregivers, and health care providers as they interact as a care team. To design a research methodology that can support systematic exploration of the experiences of patients with HF, caregivers, and health care providers as they interact as a care team. This article describes in detail a methodology that we have piloted and are currently using in a multisite study of HF care teams. We describe three aspects of the methodology: the theoretical framework, an innovative sampling strategy, and an iterative system of data collection and analysis that incorporates four data sources and four analytical steps. We anticipate that this innovative methodology will support groundbreaking research in both HF care and other team settings in which palliative integration efforts are emerging for patients with advanced nonmalignant disease. Copyright © 2013 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

  18. A novel approach to surveying sturgeon using side-scan sonar and occupancy modeling

    Science.gov (United States)

    Flowers, H. Jared; Hightower, Joseph E.

    2013-01-01

    Technological advances represent opportunities to enhance and supplement traditional fisheries sampling approaches. One example with growing importance for fisheries research is hydroacoustic technologies such as side-scan sonar. Advantages of side-scan sonar over traditional techniques include the ability to sample large areas efficiently and the potential to survey fish without physical handling-important for species of conservation concern, such as endangered sturgeons. Our objectives were to design an efficient survey methodology for sampling Atlantic Sturgeon Acipenser oxyrinchus by using side-scan sonar and to developmethods for analyzing these data. In North Carolina and South Carolina, we surveyed six rivers thought to contain varying abundances of sturgeon by using a combination of side-scan sonar, telemetry, and video cameras (i.e., to sample jumping sturgeon). Lower reaches of each river near the saltwater-freshwater interface were surveyed on three occasions (generally successive days), and we used occupancy modeling to analyze these data.We were able to detect sturgeon in five of six rivers by using these methods. Side-scan sonar was effective in detecting sturgeon, with estimated gear-specific detection probabilities ranging from 0.2 to 0.5 and river-specific occupancy estimates (per 2-km river segment) ranging from 0.0 to 0.8. Future extensions of this occupancy modeling framework will involve the use of side-scan sonar data to assess sturgeon habitat and abundance in different river systems.

  19. Like a virgin (mother): analysis of data from a longitudinal, US population representative sample survey

    OpenAIRE

    Herring, Amy H; Attard, Samantha M; Gordon-Larsen, Penny; Joyner, William H; Halpern, Carolyn T

    2013-01-01

    Objective To estimate the incidence of self report of pregnancy without sexual intercourse (virgin pregnancy) and factors related to such reporting, in a population representative group of US adolescents and young adults. Design Longitudinal, population representative sample survey. Setting Nationally representative, multiethnic National Longitudinal Study of Adolescent Health, United States. Participants 7870 women enrolled at wave I (1995) and completing the most recent wave of data collect...

  20. INTEGRATED SURVEY FOR ARCHITECTURAL RESTORATION: A METHODOLOGICAL COMPARISON OF TWO CASE STUDIES

    Directory of Open Access Journals (Sweden)

    G. Bianchi

    2016-06-01

    Full Text Available A preliminary survey campaign is essential in projects of restoration, urban renewal, rebuilding or promotion of architectural heritage. Today several survey techniques allow full 3D object restitution and modelling that provides a richer description than simple 2D representations. However, the amount of data to collect increases dramatically and a trade-off between efficiency and productivity from one side and assuring accuracy and completeness of the results on the other must be found. Depending on the extent and the complexity of the task, a single technique or a combination of several ones might be employed. Especially when documentation at different scales and with different levels of detail are foreseen, the latter will likely be necessary. The paper describes two architectural surveys in Italy: the old village of Navelli (AQ, affected by the earthquake in 2009, and the two most relevant remains in Codiponte (MS, damaged by the earthquake in 2013, both in the context of a project of restoration and conservation. In both sites, a 3D survey was necessary to represent effectively the objects. An integrated survey campaign was performed in both cases, which consists of a GPS network as support for georeferencing, an aerial survey and a field survey made by laser scanner and close range photogrammetry. The two case studies, thanks to their peculiarities, can be taken as exemplar to wonder if the integration of different surveying techniques is today still mandatory or, considering the technical advances of each technology, it is in fact just optional.

  1. HandiVIH--A population-based survey to understand the vulnerability of people with disabilities to HIV and other sexual and reproductive health problems in Cameroon: protocol and methodological considerations.

    Science.gov (United States)

    De Beaudrap, Pierre; Pasquier, Estelle; Tchoumkeu, Alice; Touko, Adonis; Essomba, Frida; Brus, Aude; Desgrées du Loû, Annabel; Aderemi, Toyin Janet; Hanass-Hancock, Jill; Eide, Arne Henning; Mont, Daniel; Mac-Seing, Muriel; Beninguisse, Gervais

    2016-02-04

    In resource-limited countries, people with disabilities seem to be particularly vulnerable to HIV infection due to barriers to accessing information and services, frequent exposure to sexual violence and social exclusion. However, they have often been left behind in the HIV response, probably because of the lack of reliable epidemiological data measuring this vulnerability. Multiple challenges in conducting good quality epidemiological surveys on people with disabilities require innovative methods to better understand the link between disability and HIV. This paper describes how the design and methods of the HandiVIH study were adapted to document the vulnerability of people with disabilities to HIV, and to compare their situation with that of people without disabilities. The HandiVIH project aims to combine quantitative and qualitative data. The quantitative component is a cross-sectional survey with a control group conducted in Yaoundé (Cameroon). A two-phase random sampling is used (1) to screen people with disabilities from the general population using the Washington Group questionnaire and, (2) to create a matched control group. An HIV test is proposed to each study participant. Additionally, a questionnaire including a life-event interview is used to collect data on respondents' life-course history of social isolation, employment, sexual partnership, HIV risk factors and fertility. Before the cross-sectional survey, a qualitative exploratory study was implemented to identify challenges in conducting the survey and possible solutions. Information on people with disabilities begging in the streets and members of disabled people's organisations is collected separately. This study has been approved by the two ethical committees. Special attention has been paid on how to adapt the consenting process to persons with intellectual disabilities. The methodological considerations discussed in this paper may contribute to the development of good practices for

  2. Development Methodology for an Integrated Legal Cadastre

    NARCIS (Netherlands)

    Hespanha, J.P.

    2012-01-01

    This Thesis describes the research process followed in order to achieve a development methodology applicable to the reform of cadastral systems with a legal basis. It was motivated by the author’s participation in one of the first surveying and mapping operations for a digital cadastre in Portugal,

  3. Formerly utilized MED/AEC sites remedial action program. Radiological survey of the Middlesex Sampling Plant, Middlesex, New Jersey. Final report

    International Nuclear Information System (INIS)

    1977-11-01

    The results of a radiological survey of the former Middlesex Sampling Plant, Middlesex, New Jersey, are presented in this report. The surveyed property served as a uranium ore sampling plant during the 1940's and early 1950's. It was released for unrestricted use in 1968 following a radiological survey by the Atomic Energy Commission and is now a reserve training center for the U.S. Marine Sixth Motor Transport Battalion. The present survey was undertaken to determine whether the existing radiological status of the property is consistent with current health guidelines and radiation protection practices. The radiological survey included measurement of residual alpha and beta-gamma contamination levels, radon and radon daughter concentrations in buildings, external gamma radiation levels on the site and on adjacent property, and radium concentrations in soil on the site and on adjacent property. Surface contamination levels exceeded U.S. Nuclear Regulatory Commission (NRC) guidelines and 222 Rn concentration levels exceeded the non-occupational maximum permissible concentration MPC/sub a/ of 3 pCi/liter in some structures. These results indicate the possible need for extensive radon and radon daughter measurements in structures both onsite and offsite over periods as suggested by the U.S. Surgeon General

  4. CHAracteristics of research studies that iNfluence practice: a GEneral survey of Canadian orthopaedic Surgeons (CHANGES): a pilot survey.

    Science.gov (United States)

    de Sa, Darren; Thornley, Patrick; Evaniew, Nathan; Madden, Kim; Bhandari, Mohit; Ghert, Michelle

    2015-01-01

    Evidence Based Medicine (EBM) is increasingly being applied to inform clinical decision-making in orthopaedic surgery. Despite the promotion of EBM in Orthopaedic Surgery, the adoption of results from high quality clinical research seems highly unpredictable and does not appear to be driven strictly by randomized trial data. The objective of this study was to pilot a survey to determine if we could identify surgeon opinions on the characteristics of research studies that are perceived as being most likely to influence clinical decision-making among orthopaedic surgeons in Canada. A 28-question electronic survey was distributed to active members of the Canadian Orthopaedic Association (COA) over a period of 11 weeks. The questionnaire sought to analyze the influence of both extrinsic and intrinsic characteristics of research studies and their potential to influence practice patterns. Extrinsic factors included the perceived journal quality and investigator profiles, economic impact, peer/patient/industry influence and individual surgeon residency/fellowship training experiences. Intrinsic factors included study design, sample size, and outcomes reported. Descriptive statistics are provided. Of the 109 members of the COA who opened the survey, 95 (87%) completed the survey in its entirety. The overall response rate was 11% (95/841). Surgeons achieved consensus on the influence of three key designs on their practices: 1) randomized controlled trials 94 (99%), 2) meta-analysis 83 (87%), and 3) systematic reviews 81 (85%). Sixty-seven percent of surgeons agreed that studies with sample sizes of 101-500 or more were more likely to influence clinical practice than smaller studies (n = design influencing adoption included 1) reputation of the investigators (99%) and 2) perceived quality of the journal (75%). Although study design and sample size (i.e. minimum of 100 patients) have some influence on clinical decision making, surgeon respondents are equally influenced

  5. Sampling and analytical methodologies for instrumental neutron activation analysis of airborne particulate matter

    International Nuclear Information System (INIS)

    1992-01-01

    The IAEA supports a number of projects having to do with the analysis of airborne particulate matter by nuclear techniques. Most of this work involves the use of activation analysis in its various forms, particularly instrumental neutron activation analysis (INAA). This technique has been widely used in many different countries for the analysis of airborne particulate matter, and there are already many publications in scientific journals, books and reports describing such work. The present document represents an attempt to summarize the most important features of INAA as applied to the analysis of airborne particulate matter. It is intended to serve as a set of guidelines for use by participants in the IAEA's own programmes, and other scientists, who are not yet fully experienced in the application of INAA to airborne particulate samples, and who wish either to make a start on using this technique or to improve their existing procedures. The methodologies for sampling described in this document are of rather general applicability, although they are presented here in a way that takes account of the particular requirements arising from the use of INAA as the analytical technique. The analytical part of the document, however, is presented in a form that is applicable only to INAA. (Subsequent publications in this series are expected to deal specifically with other nuclear related techniques such as energy dispersive X ray fluorescence (ED-XRF) and particle induced X ray emission (PIXE) analysis). Although the methods and procedures described here have been found through experience to yield acceptable results, they should not be considered mandatory. Any other procedure used should, however, be chosen to be capable of yielding results at least of equal quality to those described

  6. Sampling and analytical methodologies for instrumental neutron activation analysis of airborne particulate matter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-01

    The IAEA supports a number of projects having to do with the analysis of airborne particulate matter by nuclear techniques. Most of this work involves the use of activation analysis in its various forms, particularly instrumental neutron activation analysis (INAA). This technique has been widely used in many different countries for the analysis of airborne particulate matter, and there are already many publications in scientific journals, books and reports describing such work. The present document represents an attempt to summarize the most important features of INAA as applied to the analysis of airborne particulate matter. It is intended to serve as a set of guidelines for use by participants in the IAEA's own programmes, and other scientists, who are not yet fully experienced in the application of INAA to airborne particulate samples, and who wish either to make a start on using this technique or to improve their existing procedures. The methodologies for sampling described in this document are of rather general applicability, although they are presented here in a way that takes account of the particular requirements arising from the use of INAA as the analytical technique. The analytical part of the document, however, is presented in a form that is applicable only to INAA. (Subsequent publications in this series are expected to deal specifically with other nuclear related techniques such as energy dispersive X ray fluorescence (ED-XRF) and particle induced X ray emission (PIXE) analysis). Although the methods and procedures described here have been found through experience to yield acceptable results, they should not be considered mandatory. Any other procedure used should, however, be chosen to be capable of yielding results at least of equal quality to those described.

  7. Benchmarking survey for recycling.

    Energy Technology Data Exchange (ETDEWEB)

    Marley, Margie Charlotte; Mizner, Jack Harry

    2005-06-01

    This report describes the methodology, analysis and conclusions of a comparison survey of recycling programs at ten Department of Energy sites including Sandia National Laboratories/New Mexico (SNL/NM). The goal of the survey was to compare SNL/NM's recycling performance with that of other federal facilities, and to identify activities and programs that could be implemented at SNL/NM to improve recycling performance.

  8. Sampling in health geography: reconciling geographical objectives and probabilistic methods. An example of a health survey in Vientiane (Lao PDR

    Directory of Open Access Journals (Sweden)

    Bochaton Audrey

    2007-06-01

    Full Text Available Abstract Background Geographical objectives and probabilistic methods are difficult to reconcile in a unique health survey. Probabilistic methods focus on individuals to provide estimates of a variable's prevalence with a certain precision, while geographical approaches emphasise the selection of specific areas to study interactions between spatial characteristics and health outcomes. A sample selected from a small number of specific areas creates statistical challenges: the observations are not independent at the local level, and this results in poor statistical validity at the global level. Therefore, it is difficult to construct a sample that is appropriate for both geographical and probability methods. Methods We used a two-stage selection procedure with a first non-random stage of selection of clusters. Instead of randomly selecting clusters, we deliberately chose a group of clusters, which as a whole would contain all the variation in health measures in the population. As there was no health information available before the survey, we selected a priori determinants that can influence the spatial homogeneity of the health characteristics. This method yields a distribution of variables in the sample that closely resembles that in the overall population, something that cannot be guaranteed with randomly-selected clusters, especially if the number of selected clusters is small. In this way, we were able to survey specific areas while minimising design effects and maximising statistical precision. Application We applied this strategy in a health survey carried out in Vientiane, Lao People's Democratic Republic. We selected well-known health determinants with unequal spatial distribution within the city: nationality and literacy. We deliberately selected a combination of clusters whose distribution of nationality and literacy is similar to the distribution in the general population. Conclusion This paper describes the conceptual reasoning behind

  9. Sampling in health geography: reconciling geographical objectives and probabilistic methods. An example of a health survey in Vientiane (Lao PDR).

    Science.gov (United States)

    Vallée, Julie; Souris, Marc; Fournet, Florence; Bochaton, Audrey; Mobillion, Virginie; Peyronnie, Karine; Salem, Gérard

    2007-06-01

    Geographical objectives and probabilistic methods are difficult to reconcile in a unique health survey. Probabilistic methods focus on individuals to provide estimates of a variable's prevalence with a certain precision, while geographical approaches emphasise the selection of specific areas to study interactions between spatial characteristics and health outcomes. A sample selected from a small number of specific areas creates statistical challenges: the observations are not independent at the local level, and this results in poor statistical validity at the global level. Therefore, it is difficult to construct a sample that is appropriate for both geographical and probability methods. We used a two-stage selection procedure with a first non-random stage of selection of clusters. Instead of randomly selecting clusters, we deliberately chose a group of clusters, which as a whole would contain all the variation in health measures in the population. As there was no health information available before the survey, we selected a priori determinants that can influence the spatial homogeneity of the health characteristics. This method yields a distribution of variables in the sample that closely resembles that in the overall population, something that cannot be guaranteed with randomly-selected clusters, especially if the number of selected clusters is small. In this way, we were able to survey specific areas while minimising design effects and maximising statistical precision. We applied this strategy in a health survey carried out in Vientiane, Lao People's Democratic Republic. We selected well-known health determinants with unequal spatial distribution within the city: nationality and literacy. We deliberately selected a combination of clusters whose distribution of nationality and literacy is similar to the distribution in the general population. This paper describes the conceptual reasoning behind the construction of the survey sample and shows that it can be

  10. Performance-based methodology for assessing seismic vulnerability and capacity of buildings

    Science.gov (United States)

    Shibin, Lin; Lili, Xie; Maosheng, Gong; Ming, Li

    2010-06-01

    This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacitydemand-diagram method. The spectral displacement ( S d ) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between S d and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.

  11. Issues in environmental survey design

    International Nuclear Information System (INIS)

    Iachan, R.

    1989-01-01

    Several environmental survey design issues are discussed and illustrated with surveys designed by Research Triangle Institute statisticians. Issues related to sampling and nonsampling errors are illustrated for indoor air quality surveys, radon surveys, pesticide surveys, and occupational and personal exposure surveys. Sample design issues include the use of auxiliary information (e.g. for stratification), and sampling in time. We also discuss the reduction and estimation of nonsampling errors, including nonresponse and measurement bias

  12. Bibliographic survey on methodologies for development of health database of the population in case of cancer occurrences; Levantamento bibliografico sobre metodologias para elaboracao de um banco de dados da saude da populacao em casos de ocorrencias de cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cavinato, Christianne C.; Andrade, Delvonei A. de; Sabundjian, Gaiane, E-mail: christiannecobellocavinato@gmail.com, E-mail: delvonei@ipen.br, E-mail: gdjian@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Diz, Maria Del Pilar E., E-mail: maria.pilar@icesp.org.br [Instituto do Cancer do Estado de Sao Paulo (ICESP), Sao Paulo, SP (Brazil)

    2014-07-01

    The objective is to make a survey of existing methodologies and for the development of public health database, focusing on health (fatal and nonfatal cancer) of the population surrounding a nuclear facility, for purposes of calculating the environmental cost of the same. From methodologies found to develop this type of database, a methodology will be developed to be applied to the internal public of IPEN/CNEN-SP, Brazil, as a pre-test for the acquisition of health information desired.

  13. Online Public Access Catalog User Studies: A Review of Research Methodologies, March 1986-November 1989.

    Science.gov (United States)

    Seymour, Sharon

    1991-01-01

    Review of research methodologies used in studies of online public access catalog (OPAC) users finds that a variety of research methodologies--e.g., surveys, transaction log analysis, interviews--have been used with varying degrees of expertise. It is concluded that poor research methodology resulting from limited training and resources limits the…

  14. Network Sampling with Memory: A proposal for more efficient sampling from social networks

    Science.gov (United States)

    Mouw, Ted; Verdery, Ashton M.

    2013-01-01

    Techniques for sampling from networks have grown into an important area of research across several fields. For sociologists, the possibility of sampling from a network is appealing for two reasons: (1) A network sample can yield substantively interesting data about network structures and social interactions, and (2) it is useful in situations where study populations are difficult or impossible to survey with traditional sampling approaches because of the lack of a sampling frame. Despite its appeal, methodological concerns about the precision and accuracy of network-based sampling methods remain. In particular, recent research has shown that sampling from a network using a random walk based approach such as Respondent Driven Sampling (RDS) can result in high design effects (DE)—the ratio of the sampling variance to the sampling variance of simple random sampling (SRS). A high design effect means that more cases must be collected to achieve the same level of precision as SRS. In this paper we propose an alternative strategy, Network Sampling with Memory (NSM), which collects network data from respondents in order to reduce design effects and, correspondingly, the number of interviews needed to achieve a given level of statistical power. NSM combines a “List” mode, where all individuals on the revealed network list are sampled with the same cumulative probability, with a “Search” mode, which gives priority to bridge nodes connecting the current sample to unexplored parts of the network. We test the relative efficiency of NSM compared to RDS and SRS on 162 school and university networks from Add Health and Facebook that range in size from 110 to 16,278 nodes. The results show that the average design effect for NSM on these 162 networks is 1.16, which is very close to the efficiency of a simple random sample (DE=1), and 98.5% lower than the average DE we observed for RDS. PMID:24159246

  15. Sampling knowledge: the hermeneutics of snowball sampling in qualitative research

    OpenAIRE

    Noy, Chaim

    2008-01-01

    During the past two decades we have witnessed a rather impressive growth of theoretical innovations and conceptual revisions of epistemological and methodological approaches within constructivist-qualitative quarters of the social sciences. Methodological discussions have commonly addressed a variety of methods for collecting and analyzing empirical material, yet the critical grounds upon which these were reformulated have rarely been extended to embrace sampling concepts and procedures. The ...

  16. Pesquisa Mundial de Saúde: aspectos metodológicos e articulação com a Organização Mundial da Saúde World Health Survey: methodological aspects and interface with the World Health Organization

    Directory of Open Access Journals (Sweden)

    Célia Landmann Szwarcwald

    2008-05-01

    financing and in health status, the proposal received countless criticisms from both conceptual and methodological viewpoints. During the redesign phase, in order to provide information about the health status of the population, the WHO proposed the application of the World Health Survey (WHS. In Brazil, the WHS was carried in 2003 for establishing consistent parameters to evaluate heath status and health care responsiveness, in addition to measuring socioeconomic health inequalities. The survey interviewed 5,000 individuals, aged 18 and above, nationwide. The sample design had three selection stages. In the first stage, 250 census tracts were systematically selected with probability proportional to size. In the second stage, households were selected with equal probability using an inverse sample design to assure 20 interviews by sector. In each household, just one adult (18 years or more was selected with equal probability to respond to the individual questionnaire. A modular questionnaire was translated and adapted from the one originally proposed by the WHO. Sample weights were based on the inverse of probabilities of inclusion in the sample calculated for each selection stage. In this paper, we describe the methodological aspects of the survey and the interface process with the WHO to conduct the WHS in Brazil.

  17. Balanced sampling

    NARCIS (Netherlands)

    Brus, D.J.

    2015-01-01

    In balanced sampling a linear relation between the soil property of interest and one or more covariates with known means is exploited in selecting the sampling locations. Recent developments make this sampling design attractive for statistical soil surveys. This paper introduces balanced sampling

  18. Mapping neighborhood scale survey responses with uncertainty metrics

    Directory of Open Access Journals (Sweden)

    Charles Robert Ehlschlaeger

    2016-12-01

    Full Text Available This paper presents a methodology of mapping population-centric social, infrastructural, and environmental metrics at neighborhood scale. This methodology extends traditional survey analysis methods to create cartographic products useful in agent-based modeling and geographic information analysis. It utilizes and synthesizes survey microdata, sub-upazila attributes, land use information, and ground truth locations of attributes to create neighborhood scale multi-attribute maps. Monte Carlo methods are employed to combine any number of survey responses to stochastically weight survey cases and to simulate survey cases' locations in a study area. Through such Monte Carlo methods, known errors from each of the input sources can be retained. By keeping individual survey cases as the atomic unit of data representation, this methodology ensures that important covariates are retained and that ecological inference fallacy is eliminated. These techniques are demonstrated with a case study from the Chittagong Division in Bangladesh. The results provide a population-centric understanding of many social, infrastructural, and environmental metrics desired in humanitarian aid and disaster relief planning and operations wherever long term familiarity is lacking. Of critical importance is that the resulting products have easy to use explicit representation of the errors and uncertainties of each of the input sources via the automatically generated summary statistics created at the application's geographic scale.

  19. Survey and selection of assessment methodologies for GAVE options

    International Nuclear Information System (INIS)

    Weterings, R.

    1999-05-01

    The Dutch government is interested in the possibilities for a market introduction of new gaseous and liquid energy carriers. To this purpose the GAVE-programme was recently set up. This study is carried out within the framework of the GAVE-programme and aims at the selection of methodologies for assessing the technological, economic, ecological and social perspectives of these new energy options (so-called GAVE-options). Based on the results of these assessments the Dutch ministries of Housing, Planning and Environment (VROM) and Economic Affairs (EZ) will decide at the end of 1999 about starting demonstration projects of promising energy carriers

  20. Design methodology of Dutch banknotes

    Science.gov (United States)

    de Heij, Hans A. M.

    2000-04-01

    Since the introduction of a design methodology for Dutch banknotes, the quality of Dutch paper currency has improved in more than one way. The methodology is question provides for (i) a design policy, which helps fix clear objectives; (ii) design management, to ensure a smooth cooperation between the graphic designer, printer, papermaker an central bank, (iii) a program of requirements, a banknote development guideline for all parties involved. This systematic approach enables an objective selection of design proposals, including security features. Furthermore, the project manager obtains regular feedback from the public by conducting market surveys. Each new design of a Netherlands Guilder banknote issued by the Nederlandsche Bank of the past 50 years has been an improvement on its predecessor in terms of value recognition, security and durability.

  1. [Sampling and measurement methods of the protocol design of the China Nine-Province Survey for blindness, visual impairment and cataract surgery].

    Science.gov (United States)

    Zhao, Jia-liang; Wang, Yu; Gao, Xue-cheng; Ellwein, Leon B; Liu, Hu

    2011-09-01

    To design the protocol of the China nine-province survey for blindness, visual impairment and cataract surgery to evaluate the prevalence and main causes of blindness and visual impairment, and the prevalence and outcomes of the cataract surgery. The protocol design was began after accepting the task for the national survey for blindness, visual impairment and cataract surgery from the Department of Medicine, Ministry of Health, China, in November, 2005. The protocol in Beijing Shunyi Eye Study in 1996 and Guangdong Doumen County Eye Study in 1997, both supported by World Health Organization, was taken as the basis for the protocol design. The relative experts were invited to discuss and prove the draft protocol. An international advisor committee was established to examine and approve the draft protocol. Finally, the survey protocol was checked and approved by the Department of Medicine, Ministry of Health, China and Prevention Program of Blindness and Deafness, WHO. The survey protocol was designed according to the characteristics and the scale of the survey. The contents of the protocol included determination of target population and survey sites, calculation of the sample size, design of the random sampling, composition and organization of the survey teams, determination of the examinee, the flowchart of the field work, survey items and methods, diagnostic criteria of blindness and moderate and sever visual impairment, the measures of the quality control, the methods of the data management. The designed protocol became the standard and practical protocol for the survey to evaluate the prevalence and main causes of blindness and visual impairment, and the prevalence and outcomes of the cataract surgery.

  2. THE ALFALFA H α SURVEY. I. PROJECT DESCRIPTION AND THE LOCAL STAR FORMATION RATE DENSITY FROM THE FALL SAMPLE

    International Nuclear Information System (INIS)

    Sistine, Angela Van; Salzer, John J.; Janowiecki, Steven; Sugden, Arthur; Giovanelli, Riccardo; Haynes, Martha P.; Jaskot, Anne E.; Wilcots, Eric M.

    2016-01-01

    The ALFALFA H α survey utilizes a large sample of H i-selected galaxies from the ALFALFA survey to study star formation (SF) in the local universe. ALFALFA H α contains 1555 galaxies with distances between ∼20 and ∼100 Mpc. We have obtained continuum-subtracted narrowband H α images and broadband R images for each galaxy, creating one of the largest homogeneous sets of H α images ever assembled. Our procedures were designed to minimize the uncertainties related to the calculation of the local SF rate density (SFRD). The galaxy sample we constructed is as close to volume-limited as possible, is a robust statistical sample, and spans a wide range of galaxy environments. In this paper, we discuss the properties of our Fall sample of 565 galaxies, our procedure for deriving individual galaxy SF rates, and our method for calculating the local SFRD. We present a preliminary value of log(SFRD[ M ⊙ yr −1 Mpc −3 ]) = −1.747 ± 0.018 (random) ±0.05 (systematic) based on the 565 galaxies in our Fall sub-sample. Compared to the weighted average of SFRD values around z ≈ 2, our local value indicates a drop in the global SFRD of a factor of 10.2 over that lookback time.

  3. Air pollution monitoring - a methodological approach

    International Nuclear Information System (INIS)

    Trajkovska Trpevska, Magdalena

    2002-01-01

    Methodology for monitoring the emission of polluters in the air is a complex concept that in general embraces following fazes: sampling, laboratory treatment, and interpretation of results. In Company for technological and laboratory investigation and environmental protection - Mining Institute Skopje, the control of emission of polluters in the air is performing according methodology based in general on the recommendation of standard VDI 2.066 prescribe from Ministry of Ecology in Germany, because adequate legislation in our country does not exist. In this article the basic treatment of methodology for the air polluters emission control is presented. (Original)

  4. Sampling and analysis plan for the preoperational environmental survey for the immobilized low activity waste (ILAW) project W-465

    International Nuclear Information System (INIS)

    Mitchell, R.M.

    1998-01-01

    This document provides a detailed description of the Sampling and Analysis Plan for the Preoperational Survey to be conducted at the Immobilized Low Activity Waste (ILAW) Project Site in the 200 East Area

  5. A random cluster survey and a convenience sample give comparable estimates of immunity to vaccine preventable diseases in children of school age in Victoria, Australia.

    Science.gov (United States)

    Kelly, Heath; Riddell, Michaela A; Gidding, Heather F; Nolan, Terry; Gilbert, Gwendolyn L

    2002-08-19

    We compared estimates of the age-specific population immunity to measles, mumps, rubella, hepatitis B and varicella zoster viruses in Victorian school children obtained by a national sero-survey, using a convenience sample of residual sera from diagnostic laboratories throughout Australia, with those from a three-stage random cluster survey. When grouped according to school age (primary or secondary school) there was no significant difference in the estimates of immunity to measles, mumps, hepatitis B or varicella. Compared with the convenience sample, the random cluster survey estimated higher immunity to rubella in samples from both primary (98.7% versus 93.6%, P = 0.002) and secondary school students (98.4% versus 93.2%, P = 0.03). Despite some limitations, this study suggests that the collection of a convenience sample of sera from diagnostic laboratories is an appropriate sampling strategy to provide population immunity data that will inform Australia's current and future immunisation policies. Copyright 2002 Elsevier Science Ltd.

  6. Appalachian National Scenic Trail pilot survey

    Science.gov (United States)

    Stan Zarnoch; Michael Bowker; Ken Cordell; Matt Owens; Gary T. Green; Allison Ginn

    2011-01-01

    Visitation statistics on the Appalachian National Scenic Trail (AT) are important for management and Federal Government reporting purposes. However, no survey methodology has been developed to obtain accurate trailwide estimates over linear trails that traverse many hundreds of back-country miles. This research develops a stratified random survey design which utilizes...

  7. The measurement invariance of job diagnostic survey (JDS) across three university student groups

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Gomez, M.; Marin-Garcia, J.A.; Girado Omeara, M.

    2016-07-01

    The main purpose of this study is to apply a multigroup confirmatory analysis to examine the measurement invariance (MI) of the adapted version of the Job Diagnosis Survey (JDS) as a measurement tool that analyses the relationship between the features of teaching methodologies with university students’ motivation and satisfaction across data collected on different degrees and academic years. Design/methodology/approach: Confirmatory factor analysis was carried out using a multigroup structural equation model, using the program EQS 6.1 to test the invariance of the adapted version of JDS in a sample constituted by 535 student of a Spanish public university. The assessment of invariance included the levels of configural, metric, scalar, covariance and latent variables invariance. Several goodness-of-fit measures were assessed... (Author)

  8. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 128 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Tonsina area in the Chugach Mountains, Valdez quadrangle, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical databases of both agencies

  9. BMR in a Brazilian adult probability sample: the Nutrition, Physical Activity and Health Survey.

    Science.gov (United States)

    Anjos, Luiz A; Wahrlich, Vivian; Vasconcellos, Mauricio Tl

    2014-04-01

    To measure BMR in a probability sample of adults from an urban city of Brazil and to compare indirectly measured BMR (BMRi) with BMR predicted from different equations. BMR data were obtained by indirect calorimetry and estimated by different predictive equations (Schofield; Harris and Benedict; Henry and Rees). Anthropometric and body composition measures were also obtained. The Nutrition, Physical Activity and Health Survey (PNAFS), a household survey conducted in Niterói, Rio de Janeiro state, Brazil. Representative sample of 529 adults (aged ≥20 years; 339 females) living in Niterói, Rio de Janeiro state, Brazil. Mean BMRi values were 5839.7 (se 73.9) kJ/d and 4758.1 (se 39.5) kJ/d for men and women, respectively. Predicted BMR by all equations was significantly higher (difference between means and 95% CI did not include zero) than BMRi in both men and women of all ages. Overall bias in BMR (predicted BMR minus BMRi) using the Schofield equations (overestimation of about 20%) was higher than when using the Henry and Rees equations (13% and 16% overestimation for males and females, respectively). The percentage of individuals whose BMR predicted by the Schofield equations fell within 10% of BMRi was very low (7.8% and 14.1% of males nd females, respectively). Current available predictive equations of BMR are not adequate to estimate BMR in Brazilians living in Niterói, Rio de Janeiro, Brazil.

  10. Scientists' attitudes on science and values: Case studies and survey methods in philosophy of science.

    Science.gov (United States)

    Steel, Daniel; Gonnerman, Chad; O'Rourke, Michael

    2017-06-01

    This article examines the relevance of survey data of scientists' attitudes about science and values to case studies in philosophy of science. We describe two methodological challenges confronting such case studies: 1) small samples, and 2) potential for bias in selection, emphasis, and interpretation. Examples are given to illustrate that these challenges can arise for case studies in the science and values literature. We propose that these challenges can be mitigated through an approach in which case studies and survey methods are viewed as complementary, and use data from the Toolbox Dialogue Initiative to illustrate this claim. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The Canadian Human Activity Pattern Survey: report of methods and population surveyed.

    Science.gov (United States)

    Leech, J A; Wilby, K; McMullen, E; Laporte, K

    1996-01-01

    The assessment of health risk due to environmental contaminants depends upon accurate estimates of the distribution of population exposures. Exposure assessment, in turn, requires information on the time people spend in micro-environments and their activities during periods of exposure. This paper describes preliminary results including study methodology and population sampled in a large Canadian survey of time-activity patterns. A 24-hour diary recall survey was performed in 2381 households (representing a 65% response rate) to describe in detail the timing, location and activity pattern of one household member (the adult or child with the next birthday). Four cities (Toronto, Vancouver, Edmonton and Saint John, NB) and their suburbs were sampled by random-digit dialling over a nine-month period in 1994/1995. Supplemental questionnaires inquiring about sociodemographic information, house and household characteristics and potential exposure to toxins in the air and water were also administered. In general, the results show that respondents spend the majority of their time indoors (88.6%) with smaller proportions of time outdoors (6.1%) and in vehicles (5.3%). Children under the age of 12 spend more time both indoors and outdoors and less time in transit than do adults. The data from this study will be used to define more accurately the exposure of Canadians to a variety of toxins in exposure assessment models and to improve upon the accuracy of risk assessment for a variety of acute and chronic health effects known or suspected to be related to environmental exposures.

  12. Survey of statistical and sampling needs for environmental monitoring of commercial low-level radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Eberhardt, L.L.; Thomas, J.M.

    1986-07-01

    This project was designed to develop guidance for implementing 10 CFR Part 61 and to determine the overall needs for sampling and statistical work in characterizing, surveying, monitoring, and closing commercial low-level waste sites. When cost-effectiveness and statistical reliability are of prime importance, then double sampling, compositing, and stratification (with optimal allocation) are identified as key issues. If the principal concern is avoiding questionable statistical practice, then the applicability of kriging (for assessing spatial pattern), methods for routine monitoring, and use of standard textbook formulae in reporting monitoring results should be reevaluated. Other important issues identified include sampling for estimating model parameters and the use of data from left-censored (less than detectable limits) distributions

  13. Bar Frequency & Galaxy Host Properties using the Spitzer Survey of Stellar Structure in Galaxies (S4G)

    Science.gov (United States)

    Sheth, Kartik; Mizusawa, T.; Kim, T.; Munoz-Mateos, J.; Regan, M. W.; de Swardt, B.; Gadotti, D.; S4G Team

    2011-01-01

    Using the volume limited sample of 2,331 nearby galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G), we have classified the frequency of barred spiral galaxies. The literature abounds with frequency ranges from as low as 20% to as high as 80% but these variations are driven by the quality of the data, the sample size and the methodology of the studies. Using the 3.6 and 4.5 micron IRAC images from S4G, we are able to make a definitive measurement of the local bar fraction as a function of the galaxy host and environment. We present the results from this survey and discuss how the current bar fraction compares to the declining frequency of bars from the present day to z 1.

  14. Evaluating tablet computers as a survey tool in rural communities.

    Science.gov (United States)

    Newell, Steve M; Logan, Henrietta L; Guo, Yi; Marks, John G; Shepperd, James A

    2015-01-01

    Although tablet computers offer advantages in data collection over traditional paper-and-pencil methods, little research has examined whether the 2 formats yield similar responses, especially with underserved populations. We compared the 2 survey formats and tested whether participants' responses to common health questionnaires or perceptions of usability differed by survey format. We also tested whether we could replicate established paper-and-pencil findings via tablet computer. We recruited a sample of low-income community members living in the rural southern United States. Participants were 170 residents (black = 49%; white = 36%; other races and missing data = 15%) drawn from 2 counties meeting Florida's state statutory definition of rural with 100 persons or fewer per square mile. We randomly assigned participants to complete scales (Center for Epidemiologic Studies Depression Inventory and Regulatory Focus Questionnaire) along with survey format usability ratings via paper-and-pencil or tablet computer. All participants rated a series of previously validated posters using a tablet computer. Finally, participants completed comparisons of the survey formats and reported survey format preferences. Participants preferred using the tablet computer and showed no significant differences between formats in mean responses, scale reliabilities, or in participants' usability ratings. Overall, participants reported similar scales responses and usability ratings between formats. However, participants reported both preferring and enjoying responding via tablet computer more. Collectively, these findings are among the first data to show that tablet computers represent a suitable substitute among an underrepresented rural sample for paper-and-pencil methodology in survey research. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  15. Population trends, survival, and sampling methodologies for a population of Rana draytonii

    Science.gov (United States)

    Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A.W.; Halstead, Brian J.

    2017-01-01

    Estimating population trends provides valuable information for resource managers, but monitoring programs face trade-offs between the quality and quantity of information gained and the number of sites surveyed. We compared the effectiveness of monitoring techniques for estimating population trends of Rana draytonii (California Red-legged Frog) at Point Reyes National Seashore, California, USA, over a 13-yr period. Our primary goals were to: 1) estimate trends for a focal pond at Point Reyes National Seashore, and 2) evaluate whether egg mass counts could reliably estimate an index of abundance relative to more-intensive capture–mark–recapture methods. Capture–mark–recapture (CMR) surveys of males indicated a stable population from 2005 to 2009, despite low annual apparent survival (26.3%). Egg mass counts from 2000 to 2012 indicated that despite some large fluctuations, the breeding female population was generally stable or increasing, with annual abundance varying between 26 and 130 individuals. Minor modifications to egg mass counts, such as marking egg masses, can allow estimation of egg mass detection probabilities necessary to convert counts to abundance estimates, even when closure of egg mass abundance cannot be assumed within a breeding season. High egg mass detection probabilities (mean per-survey detection probability = 0.98 [0.89–0.99]) indicate that egg mass surveys can be an efficient and reliable method for monitoring population trends of federally threatened R. draytonii. Combining egg mass surveys to estimate trends at many sites with CMR methods to evaluate factors affecting adult survival at focal populations is likely a profitable path forward to enhance understanding and conservation of R. draytonii.

  16. Experience sampling methodology in mental health research: new insights and technical developments.

    Science.gov (United States)

    Myin-Germeys, Inez; Kasanova, Zuzana; Vaessen, Thomas; Vachon, Hugo; Kirtley, Olivia; Viechtbauer, Wolfgang; Reininghaus, Ulrich

    2018-06-01

    In the mental health field, there is a growing awareness that the study of psychiatric symptoms in the context of everyday life, using experience sampling methodology (ESM), may provide a powerful and necessary addition to more conventional research approaches. ESM, a structured self-report diary technique, allows the investigation of experiences within, and in interaction with, the real-world context. This paper provides an overview of how zooming in on the micro-level of experience and behaviour using ESM adds new insights and additional perspectives to standard approaches. More specifically, it discusses how ESM: a) contributes to a deeper understanding of psychopathological phenomena, b) allows to capture variability over time, c) aids in identifying internal and situational determinants of variability in symptomatology, and d) enables a thorough investigation of the interaction between the person and his/her environment and of real-life social interactions. Next to improving assessment of psychopathology and its underlying mechanisms, ESM contributes to advancing and changing clinical practice by allowing a more fine-grained evaluation of treatment effects as well as by providing the opportunity for extending treatment beyond the clinical setting into real life with the development of ecological momentary interventions. Furthermore, this paper provides an overview of the technical details of setting up an ESM study in terms of design, questionnaire development and statistical approaches. Overall, although a number of considerations and challenges remain, ESM offers one of the best opportunities for personalized medicine in psychiatry, from both a research and a clinical perspective. © 2018 World Psychiatric Association.

  17. THE ALFALFA H α SURVEY. I. PROJECT DESCRIPTION AND THE LOCAL STAR FORMATION RATE DENSITY FROM THE FALL SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Sistine, Angela Van [Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Salzer, John J.; Janowiecki, Steven [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States); Sugden, Arthur [Department of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115 (United States); Giovanelli, Riccardo; Haynes, Martha P. [Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853 (United States); Jaskot, Anne E. [Department of Astronomy, Smith College, Northampton, MA 01063 (United States); Wilcots, Eric M. [Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2016-06-10

    The ALFALFA H α survey utilizes a large sample of H i-selected galaxies from the ALFALFA survey to study star formation (SF) in the local universe. ALFALFA H α contains 1555 galaxies with distances between ∼20 and ∼100 Mpc. We have obtained continuum-subtracted narrowband H α images and broadband R images for each galaxy, creating one of the largest homogeneous sets of H α images ever assembled. Our procedures were designed to minimize the uncertainties related to the calculation of the local SF rate density (SFRD). The galaxy sample we constructed is as close to volume-limited as possible, is a robust statistical sample, and spans a wide range of galaxy environments. In this paper, we discuss the properties of our Fall sample of 565 galaxies, our procedure for deriving individual galaxy SF rates, and our method for calculating the local SFRD. We present a preliminary value of log(SFRD[ M {sub ⊙} yr{sup −1} Mpc{sup −3}]) = −1.747 ± 0.018 (random) ±0.05 (systematic) based on the 565 galaxies in our Fall sub-sample. Compared to the weighted average of SFRD values around z ≈ 2, our local value indicates a drop in the global SFRD of a factor of 10.2 over that lookback time.

  18. Recruiting and retaining youth and young adults: challenges and opportunities in survey research for tobacco control.

    Science.gov (United States)

    Cantrell, Jennifer; Hair, Elizabeth C; Smith, Alexandria; Bennett, Morgane; Rath, Jessica Miller; Thomas, Randall K; Fahimi, Mansour; Dennis, J Michael; Vallone, Donna

    2018-03-01

    Evaluation studies of population-based tobacco control interventions often rely on large-scale survey data from numerous respondents across many geographic areas to provide evidence of their effectiveness. Significant challenges for survey research have emerged with the evolving communications landscape, particularly for surveying hard-to-reach populations such as youth and young adults. This study combines the comprehensive coverage of an address-based sampling (ABS) frame with the timeliness of online data collection to develop a nationally representative longitudinal cohort of young people aged 15-21. We constructed an ABS frame, partially supplemented with auxiliary data, to recruit this hard-to-reach sample. Branded and tested mail-based recruitment materials were designed to bring respondents online for screening, consent and surveying. Once enrolled, respondents completed online surveys every 6 months via computer, tablet or smartphone. Numerous strategies were utilized to enhance retention and representativeness RESULTS: Results detail sample performance, representativeness and retention rates as well as device utilization trends for survey completion among youth and young adult respondents. Panel development efforts resulted in a large, nationally representative sample with high retention rates. This study is among the first to employ this hybrid ABS-to-online methodology to recruit and retain youth and young adults in a probability-based online cohort panel. The approach is particularly valuable for conducting research among younger populations as it capitalizes on their increasing access to and comfort with digital communication. We discuss challenges and opportunities of panel recruitment and retention methods in an effort to provide valuable information for tobacco control researchers seeking to obtain representative, population-based samples of youth and young adults in the U.S. as well as across the globe. © Article author(s) (or their employer

  19. Surveillance System for Risk and Protective Factors for Chronic Diseases by Telephone Survey (Vigitel): changes in weighting methodology.

    Science.gov (United States)

    Bernal, Regina Tomie Ivata; Iser, Betine Pinto Moehlecke; Malta, Deborah Carvalho; Claro, Rafael Moreira

    2017-01-01

    to introduce the methodology used to calculate post-stratification weights of the 2012 Surveillance System for Risk and Protective Factors for Chronic Diseases by Telephone Survey (Vigitel) and to compare the trends of indicators estimated by cell-by-cell weighting and raking methods. in this panel of cross-sectional studies, the prevalences of smokers, overweight, and intake of fruits and vegetables from 2006 to 2012 were estimated using the cell-by-cell weighting and raking methods. there were no differences in time trends of the indicators estimated by both methods, but the prevalence of smokers estimated by the raking method was lower than the estimated by cell-by-cell weighting, whilst the prevalence of fruit and vegetable intake was higher; for overweight, there was no difference between the methods. raking method presented higher accuracy of the estimates when compared to cell-by-cell weighting method, proving to be most convenient, although it presents register coverage bias.

  20. Some Findings Concerning Requirements in Agile Methodologies

    Science.gov (United States)

    Rodríguez, Pilar; Yagüe, Agustín; Alarcón, Pedro P.; Garbajosa, Juan

    Agile methods have appeared as an attractive alternative to conventional methodologies. These methods try to reduce the time to market and, indirectly, the cost of the product through flexible development and deep customer involvement. The processes related to requirements have been extensively studied in literature, in most cases in the frame of conventional methods. However, conclusions of conventional methodologies could not be necessarily valid for Agile; in some issues, conventional and Agile processes are radically different. As recent surveys report, inadequate project requirements is one of the most conflictive issues in agile approaches and better understanding about this is needed. This paper describes some findings concerning requirements activities in a project developed under an agile methodology. The project intended to evolve an existing product and, therefore, some background information was available. The major difficulties encountered were related to non-functional needs and management of requirements dependencies.

  1. Sample Loss and Survey Bias in Estimates of Social Security Beneficiaries: A Tale of Two Surveys.

    OpenAIRE

    John L. Czajka; James Mabli; Scott Cody

    2008-01-01

    Data from the Census Bureau’s Survey of Income and Program Participation (SIPP) and the Current Population Survey (CPS) provide information on current and potential beneficiaries served by Social Security Administration (SSA) programs. SSA also links administrative records to the records of survey respondents who provide Social Security numbers. These matched data expand the content of the SIPP and CPS files to fields available only through SSA and Internal Revenue Service records—such as l...

  2. The study of evaluation methodology of the aging and degradation researches

    International Nuclear Information System (INIS)

    Cho, C. J.; Park, Z. H.; Jeong, I. S.

    2001-01-01

    To judge the usefulness of aging related researches like PLIM (Plant lifetime Management) and aging related degradation, et. al. in PSR(Periodic Safety Review), the evaluation methodology of the R and D have been proposed up to now are reviewed. The infometric methodology is considered to be the optimum method for the evaluation of the nuclear related researches. And finally, to increase the objectiveness and reliability of the infometric methodology in the aging and degradation researches, the indexes of safety, technology and economics are introduced. From this study, the infometric methodology has the advantage of the actual engineering evaluation in the nuclear related researches with other methodologies, but for the further research, the effective construction of DB and survey of various statistics in the technical reports and papers are needed

  3. A study on assessment methodology of surveillance test interval and allowed outage time

    International Nuclear Information System (INIS)

    Che, Moo Seong; Cheong, Chang Hyeon; Lee, Byeong Cheol

    1996-07-01

    The objectives of this study is the development of methodology by which assessing the optimizes Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korea nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches is performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method

  4. A study on assessment methodology of surveillance test interval and allowed outage time

    Energy Technology Data Exchange (ETDEWEB)

    Che, Moo Seong; Cheong, Chang Hyeon; Lee, Byeong Cheol [Seoul Nationl Univ., Seoul (Korea, Republic of)] (and others)

    1996-07-15

    The objectives of this study is the development of methodology by which assessing the optimizes Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korea nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches is performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method.

  5. Are consumer surveys valuable as a service improvement tool in health services? A critical appraisal.

    Science.gov (United States)

    Patwardhan, Anjali; Patwardhan, Prakash

    2009-01-01

    In the recent climate of consumerism and consumer focused care, health and social care needs to be more responsive than ever before. Consumer needs and preferences can be elicited with accepted validity and reliability only by strict methodological control, customerisation of the questionnaire and skilled interpretation. To construct, conduct, interpret and implement improved service provision, requires a trained work force and infrastructure. This article aims to appraise various aspects of consumer surveys and to assess their value as effective service improvement tools. The customer is the sole reason organisations exist. Consumer surveys are used worldwide as service and quality of care improvement tools by all types of service providers including health service providers. The article critically appraises the value of consumer surveys as service improvement tools in health services tool and its future applications. No one type of survey is the best or ideal. The key is the selection of the correct survey methodology, unique and customised for the particular type/aspect of care being evaluated. The method used should reflect the importance of the information required. Methodological rigor is essential for the effectiveness of consumer surveys as service improvement tools. Unfortunately so far there is no universal consensus on superiority of one particular methodology over another or any benefit of one specific methodology in a given situation. More training and some dedicated resource allocation is required to develop consumer surveys. More research is needed to develop specific survey methodology and evaluation techniques for improved validity and reliability of the surveys as service improvement tools. Measurement of consumer preferences/priorities, evaluation of services and key performance scores, is not easy. Consumer surveys seem impressive tools as they provide the customer a voice for change or modification. However, from a scientific point

  6. A national survey of musculoskeletal impairment in Rwanda: prevalence, causes and service implications.

    Directory of Open Access Journals (Sweden)

    Oluwarantimi Atijosan

    Full Text Available BACKGROUND: Accurate information on the prevalence and causes of musculoskeletal impairment (MSI is lacking in low income countries. We present a new survey methodology that is based on sound epidemiological principles and is linked to the World Health Organisation's International Classification of Functioning. METHODS: Clusters were selected with probability proportionate to size. Households were selected within clusters through compact segment sampling. 105 clusters of 80 people (all ages were included. All participants were screened for MSI by a physiotherapist and medical assistant. Possible cases plus a random sample of 10% of non-MSI cases were examined further to ascertain diagnosis, aetiology, quality of life, and treatment needs. FINDINGS: 6757 of 8368 enumerated individuals (80.8% were screened. There were 352 cases, giving an overall prevalence for MSI of 5.2%. (95% CI 4.5-5.9 The prevalence of MSI increased with age and was similar in men and women. Extrapolating these estimates, there are approximately 488,000 MSI diagnoses in Rwanda. Only 8.2% of MSI cases were severe, while the majority were moderate (43.7% or mild (46.3%. Diagnostic categories comprised 11.5% congenital, 31.3% trauma, 3.8% infection, 9.0% neurological, and 44.4% non-traumatic non infective acquired. The most common individual diagnoses were joint disease (13.3%, angular limb deformity (9.7% and fracture mal- and non-union (7.2%. 96% of all cases required further treatment. INTERPRETATION: This survey demonstrates a large burden of MSI in Rwanda, which is mostly untreated. The survey methodology will be useful in other low income countries, to assist with planning services and monitoring trends.

  7. Improving the Network Scale-Up Estimator: Incorporating Means of Sums, Recursive Back Estimation, and Sampling Weights.

    Directory of Open Access Journals (Sweden)

    Patrick Habecker

    Full Text Available Researchers interested in studying populations that are difficult to reach through traditional survey methods can now draw on a range of methods to access these populations. Yet many of these methods are more expensive and difficult to implement than studies using conventional sampling frames and trusted sampling methods. The network scale-up method (NSUM provides a middle ground for researchers who wish to estimate the size of a hidden population, but lack the resources to conduct a more specialized hidden population study. Through this method it is possible to generate population estimates for a wide variety of groups that are perhaps unwilling to self-identify as such (for example, users of illegal drugs or other stigmatized populations via traditional survey tools such as telephone or mail surveys--by asking a representative sample to estimate the number of people they know who are members of such a "hidden" subpopulation. The original estimator is formulated to minimize the weight a single scaling variable can exert upon the estimates. We argue that this introduces hidden and difficult to predict biases, and instead propose a series of methodological advances on the traditional scale-up estimation procedure, including a new estimator. Additionally, we formalize the incorporation of sample weights into the network scale-up estimation process, and propose a recursive process of back estimation "trimming" to identify and remove poorly performing predictors from the estimation process. To demonstrate these suggestions we use data from a network scale-up mail survey conducted in Nebraska during 2014. We find that using the new estimator and recursive trimming process provides more accurate estimates, especially when used in conjunction with sampling weights.

  8. The VLA Sky Survey

    Science.gov (United States)

    Lacy, Mark; VLASS Survey Team, VLASS Survey Science Group

    2018-01-01

    The VLA Sky Survey (VLASS), which began in September 2017, is a seven year project to image the entire sky north of Declination -40 degrees in three epochs. The survey is being carried out in I,Q and U polarization at a frequency of 2-4GHz, and a resolution of 2.5 arcseconds, with each epoch being separated by 32 months. Raw data from the survey, along with basic "quicklook" images are made freely available shortly after observation. Within a few months, NRAO will begin making available further basic data products, including refined images and source lists. In this talk I shall describe the science goals and methodology of the survey, the current survey status, and some early results, along with plans for collaborations with external groups to produce enhanced, high level data products.

  9. Engagement with HIV prevention treatment and care among female sex workers in Zimbabwe: a respondent driven sampling survey.

    Science.gov (United States)

    Cowan, Frances M; Mtetwa, Sibongile; Davey, Calum; Fearon, Elizabeth; Dirawo, Jeffrey; Wong-Gruenwald, Ramona; Ndikudze, Theresa; Chidiya, Samson; Benedikt, Clemens; Busza, Joanna; Hargreaves, James R

    2013-01-01

    To determine the HIV prevalence and extent of engagement with HIV prevention and care among a representative sample of Zimbabwean sex workers working in Victoria Falls, Hwange and Mutare. Respondent driven sampling (RDS) surveys conducted at each site. Sex workers were recruited using respondent driven sampling with each respondent limited to recruiting 2 peers. Participants completed an interviewer-administered questionnaire and provided a finger prick blood sample for HIV antibody testing. Statistical analysis took account of sampling method. 870 women were recruited from the three sites. HIV prevalence was between 50 and 70%. Around half of those confirmed HIV positive were aware of their HIV status and of those 50-70% reported being enrolled in HIV care programmes. Overall only 25-35% of those with laboratory-confirmed HIV were accessing antiretroviral therapy. Among those reporting they were HIV negative, 21-28% reported having an HIV test in the last 6 months. Of those tested HIV negative, most (65-82%) were unaware of their status. Around two-thirds of sex workers reported consistent condom use with their clients. As in other settings, sex workers reported high rates of gender based violence and police harassment. This survey suggests that prevalence of HIV is high among sex workers in Zimbabwe and that their engagement with prevention, treatment and care is sub-optimal. Intensifying prevention and care interventions for sex workers has the potential to markedly reduce HIV and social risks for sex workers, their clients and the general population in Zimbabwe and elsewhere in the region.

  10. Demonstrating the Potential for Web-Based Survey Methodology with a Case Study.

    Science.gov (United States)

    Mertler, Craig

    2002-01-01

    Describes personal experience with using the Internet to administer a teacher-motivation and job-satisfaction survey to elementary and secondary teachers. Concludes that advantages of Web-base surveys, such as cost savings and efficiency of data collection, outweigh disadvantages, such as the limitations of listservs. (Contains 10 references.)…

  11. Gamma ray auto absorption correction evaluation methodology

    International Nuclear Information System (INIS)

    Gugiu, Daniela; Roth, Csaba; Ghinescu, Alecse

    2010-01-01

    Neutron activation analysis (NAA) is a well established nuclear technique, suited to investigate the microstructural or elemental composition and can be applied to studies of a large variety of samples. The work with large samples involves, beside the development of large irradiation devices with well know neutron field characteristics, the knowledge of perturbing phenomena and adequate evaluation of correction factors like: neutron self shielding, extended source correction, gamma ray auto absorption. The objective of the works presented in this paper is to validate an appropriate methodology for gamma ray auto absorption correction evaluation for large inhomogeneous samples. For this purpose a benchmark experiment has been defined - a simple gamma ray transmission experiment, easy to be reproduced. The gamma ray attenuation in pottery samples has been measured and computed using MCNP5 code. The results show a good agreement between the computed and measured values, proving that the proposed methodology is able to evaluate the correction factors. (authors)

  12. SDSS-II SUPERNOVA SURVEY: AN ANALYSIS OF THE LARGEST SAMPLE OF TYPE IA SUPERNOVAE AND CORRELATIONS WITH HOST-GALAXY SPECTRAL PROPERTIES

    International Nuclear Information System (INIS)

    Wolf, Rachel C.; Gupta, Ravi R.; Sako, Masao; Fischer, John A.; March, Marisa C.; Fischer, Johanna-Laina; D’Andrea, Chris B.; Smith, Mathew; Kessler, Rick; Scolnic, Daniel M.; Jha, Saurabh W.; Campbell, Heather; Nichol, Robert C.; Olmstead, Matthew D.; Richmond, Michael; Schneider, Donald P.

    2016-01-01

    Using the largest single-survey sample of Type Ia supernovae (SNe Ia) to date, we study the relationship between properties of SNe Ia and those of their host galaxies, focusing primarily on correlations with Hubble residuals (HRs). Our sample consists of 345 photometrically classified or spectroscopically confirmed SNe Ia discovered as part of the SDSS-II Supernova Survey (SDSS-SNS). This analysis utilizes host-galaxy spectroscopy obtained during the SDSS-I/II spectroscopic survey and from an ancillary program on the SDSS-III Baryon Oscillation Spectroscopic Survey that obtained spectra for nearly all host galaxies of SDSS-II SN candidates. In addition, we use photometric host-galaxy properties from the SDSS-SNS data release such as host stellar mass and star formation rate. We confirm the well-known relation between HR and host-galaxy mass and find a 3.6 σ significance of a nonzero linear slope. We also recover correlations between HR and host-galaxy gas-phase metallicity and specific star formation rate as they are reported in the literature. With our large data set, we examine correlations between HR and multiple host-galaxy properties simultaneously and find no evidence of a significant correlation. We also independently analyze our spectroscopically confirmed and photometrically classified SNe Ia and comment on the significance of similar combined data sets for future surveys.

  13. Design of the South East Asian Nutrition Survey (SEANUTS): a four-country multistage cluster design study.

    Science.gov (United States)

    Schaafsma, Anne; Deurenberg, Paul; Calame, Wim; van den Heuvel, Ellen G H M; van Beusekom, Christien; Hautvast, Jo; Sandjaja; Bee Koon, Poh; Rojroongwasinkul, Nipa; Le Nguyen, Bao Khanh; Parikh, Panam; Khouw, Ilse

    2013-09-01

    Nutrition is a well-known factor in the growth, health and development of children. It is also acknowledged that worldwide many people have dietary imbalances resulting in over- or undernutrition. In 2009, the multinational food company FrieslandCampina initiated the South East Asian Nutrition Survey (SEANUTS), a combination of surveys carried out in Indonesia, Malaysia, Thailand and Vietnam, to get a better insight into these imbalances. The present study describes the general study design and methodology, as well as some problems and pitfalls encountered. In each of these countries, participants in the age range of 0·5-12 years were recruited according to a multistage cluster randomised or stratified random sampling methodology. Field teams took care of recruitment and data collection. For the health status of children, growth and body composition, physical activity, bone density, and development and cognition were measured. For nutrition, food intake and food habits were assessed by questionnaires, whereas in subpopulations blood and urine samples were collected to measure the biochemical status parameters of Fe, vitamins A and D, and DHA. In Thailand, the researchers additionally studied the lipid profile in blood, whereas in Indonesia iodine excretion in urine was analysed. Biochemical data were analysed in certified laboratories. Study protocols and methodology were aligned where practically possible. In December 2011, data collection was finalised. In total, 16,744 children participated in the present study. Information that will be very relevant for formulating nutritional health policies, as well as for designing innovative food and nutrition research and development programmes, has become available.

  14. Variability in "1"8F-FDG PET/CT methodology of acquisition, reconstruction and analysis for oncologic imaging: state survey

    International Nuclear Information System (INIS)

    Fischer, Andreia C.F. da S.; Druzian, Aline C.; Bacelar, Alexandre; Pianta, Diego B.; Silva, Ana M. Marques da

    2016-01-01

    The SUV in "1"8F-FDG PET/CT oncological imaging is useful for cancer diagnosis, staging and treatment assessment. There are, however, several factors that can give rise to bias in SUV measurements. When using SUV as a diagnostic tool, one needs to minimize the variability in this measurement by standardization of patient preparation, acquisition and reconstruction parameters. The aim of this study is to evaluate the methodological variability in PET/CT acquisition in Rio Grande do Sul State. For that, in each department, a questionnaire was applied to survey technical information from PET/CT systems and about the acquisitions and analysis methods utilized. All departments implement quality assurance programs consistent with (inter)national recommendations. However, the acquisition and reconstruction methods of acquired PET data differ. The implementation of a harmonized strategy for quantifying the SUV is suggested, in order to obtain greater reproducibility and repeatability. (author)

  15. Controlled sample program publication No. 1: characterization of rock samples

    International Nuclear Information System (INIS)

    Ames, L.L.

    1978-10-01

    A description is presented of the methodology used and the geologic parameters measured on several rocks which are being used in round-robin laboratory and nuclide adsorption methodology experiments. Presently investigators from various laboratories are determining nuclide distribution coefficients utilizing numerous experimental techniques. Unfortunately, it appears that often the resultant data are dependent not only on the type of groundwater and rock utilized, but also on the experimentor or method used. The Controlled Sample Program is a WISAP (Waste Isolation Safety Assessment Program) attempt to resolve the apparent method and dependencies and to identify individual experimenter's bias. The rock samples characterized in an interlaboratory Kd methodology comparison program include Westerly granite, Argillaceous shale, Oolitic limestone, Sentinel Gap basalt, Conasauga shale, Climax Stock granite, anhydrite, Magenta dolomite and Culebra dolomite. Techniques used in the characterization include whole rock chemical analysis, X-ray diffraction, optical examination, electron microprobe elemental mapping, and chemical analysis of specific mineral phases. Surface areas were determined by the B.E.T. and ethylene glycol sorption methods. Cation exchange capacities were determined with 85 Sr, but were of questionable value for the high calcium rocks. A quantitative mineralogy was also estimated for each rock. Characteristics which have the potential of strongly affecting radionuclide Kd values such as the presence of sulfides, water-soluble, pH-buffering carbonates, glass, and ferrous iron were listed for each rock sample

  16. [Health services access survey for Colombian households].

    Science.gov (United States)

    Arrivillaga, Marcela; Aristizabal, Juan Carlos; Pérez, Mauricio; Estrada, Victoria Eugenia

    The aim of this study was to design and validate a health services access survey for households in Colombia to provide a methodological tool that allows the country to accumulate evidence of real-life access conditions experienced by the Colombian population. A validation study with experts and a pilot study were performed. It was conducted in the municipality of Jamundi, located in the department of Valle del Cauca, Colombia. Probabilistic, multistage and stratified cluster sampling was carried out. The final sample was 215 households. The survey was composed of 63 questions divided into five modules: socio-demographic profile of the head of the household or adult informant, household socioeconomic profile, access to preventive services, access to curative and rehabilitative services and household out of pocket expenditure. In descriptive terms, the promotion of preventive services only reached 44%; the use of these services was always highest among children younger than one year old and up to the age of ten. The perceived need for emergency medical care and hospitalisation was between 82% and 85%, but 36% perceived the quality of care to be low or very low. Delays were experienced in medical visits with GPs and specialists. The designed survey is valid, relevant and representative of access to health services in Colombia. Empirically, the pilot showed institutional weaknesses in a municipality of the country, indicating that health coverage does not in practice mean real and effective access to health services. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Infall and outflow motions towards a sample of massive star-forming regions from the RMS survey

    Science.gov (United States)

    Cunningham, N.; Lumsden, S. L.; Moore, T. J. T.; Maud, L. T.; Mendigutía, I.

    2018-06-01

    We present the results of an outflow and infall survey towards a distance-limited sample of 31 massive star-forming regions drawn from the Red MSX source (RMS) survey. The presence of young, active outflows is identified from SiO (8-7) emission and the infall dynamics are explored using HCO+/H13CO+ (4-3) emission. We investigate if the infall and outflow parameters vary with source properties, exploring whether regions hosting potentially young active outflows show similarities or differences with regions harbouring more evolved, possibly momentum-driven, `fossil' outflows. SiO emission is detected towards approximately 46 per cent of the sources. When considering sources with and without an SiO detection (i.e. potentially active and fossil outflows, respectively), only the 12CO outflow velocity shows a significant difference between samples, indicating SiO is more prevalent towards sources with higher outflow velocities. Furthermore, we find the SiO luminosity increases as a function of the Herschel 70 μm to WISE 22 μm flux ratio, suggesting the production of SiO is prevalent in younger, more embedded regions. Similarly, we find tentative evidence that sources with an SiO detection have a smaller bolometric luminosity-to-mass ratio, indicating SiO (8-7) emission is associated with potentially younger regions. We do not find a prevalence towards sources displaying signatures of infall in our sample. However, the higher energy HCO+ transitions may not be the best suited tracer of infall at this spatial resolution in these regions.

  18. India's energy security: A sample of business, government, civil society, and university perspectives

    International Nuclear Information System (INIS)

    Bambawale, Malavika Jain; Sovacool, Benjamin K.

    2011-01-01

    This article explores the concept of energy security perceived and understood by a sample of government, business, civil society, and university stakeholders in India. Based on a literature review, the authors hypothesize what energy experts suggest energy security is for India. The article then tests these hypotheses through the use of a survey completed by 172 Indian respondents. The article begins by describing its methodology before summarizing the results of the literature review to distill seven working hypotheses related to energy security in India. These hypotheses relate to (1) security of energy supply, (2) equitable access to energy services, (3) research and development of new energy technologies, (4) energy efficiency and conservation, (5) self-sufficiency and trade in energy fuels, (6) nuclear power, and (7) the energy-water nexus. It then tests these hypotheses with our survey instrument before concluding with implications for energy policy in India and beyond. - Research highlights: → We measured the concept of energy security for India through a survey that tested the importance of 16 dimensions. → For our sample of respondents from India, as hypothesized, security of fossil fuel supply, R and D in new technologies, centralized energy systems, and the availability of clean water emerged as important dimensions. → Equitable access to energy and low energy intensity did not emerge as important dimensions of energy security for our sample even though we hypothesized them to be so.

  19. METHODOLOGICAL PROPOSAL FOR COMPILING THE ILO UNEMPLOYMENT WITH MONTHLY PERIODICITY

    Directory of Open Access Journals (Sweden)

    Silvia PISICĂ

    2011-08-01

    Full Text Available Development of methodology for deriving the monthly unemployment statistics directly from the quarterly Labour Force Survey (LFS results by econometric modeling meets the requirements of insuring the information on short-term needed for employment policies, aiming to achieve the objectives of Europe 2020. Estimated monthly data series according to the methodology allow assessment of short-term trends in unemployment measured according to the criteria of the International Labour Organisation (ILO in terms of comparability with European statistics.

  20. Research Methodologies in Supply Chain Management

    DEFF Research Database (Denmark)

    Kotzab, Herbert

    . Within the 36 chapters 70 authors bring together a rich selection of theoretical and practical examples of how research methodologies are applied in supply chain management. The book contains papers on theoretical implications as well as papers on a range of key methods, such as modelling, surveys, case...... studies or action research. It will be of great interest to researchers in the area of supply chain management and logistics, but also to neighbouring fields, such as network management or global operations.......While supply chain management has risen to great prominence in recent year, there are hardly related developments in research methodologies. Yet, as supply chains cover more than one company, one central issue is how to collect and analyse data along the whole or relevant part of the supply chain...

  1. Assessing the Ecological Footprint of Ecotourism Packages: A Methodological Proposition

    Directory of Open Access Journals (Sweden)

    Maria Serena Mancini

    2018-06-01

    Full Text Available Tourism represents a key economic sector worldwide, constituting great leverage for local economic development but also putting noticeable environmental pressures on local natural resources. Ecotourism may be a viable alternative to mass tourism to minimize impacts on ecosystems, but it needs shared sustainability standards and monitoring tools to evaluate impacts. This paper presents a first methodological proposition to calculate the environmental impact of ecotourism packages through the use of an ad-hoc, customized version of the Ecological Footprint methodology. It follows a participatory, bottom-up approach to collecting input data for the four main services (Accommodation, Food & Drinks, Activity & Service, and Mobility & Transfer provided to tourists through the use of surveys and stakeholders engagement. The outcome of our approach materializes in an excel-based ecotourism workbook capable of processing input data collected through surveys and returning Ecological Footprint values for specific ecotourism packages. Although applied to ecotourism in Mediterranean Protected Areas within the context of the DestiMED project, we believe that the methodology and approach presented here can constitute a blueprint and a benchmark for future studies dealing with the impact of ecotourism packages.

  2. Geotechnical site assessment methodology

    International Nuclear Information System (INIS)

    Tunbridge, L.W.; Richards, L.R.

    1985-09-01

    The reports comprising this volume concern the research conducted on geotechnical site assessment methodology at the Carwynnen test mine in granites in Cornwall, with particular reference to the effect of structures imposed by discontinuities on the engineering behaviour of rock masses. The topics covered are: in-situ stress measurements using (a) the hydraulic fracturing method, or (b) the US Bureau of Mines deformation probe; scanline discontinuity survey - coding form and instructions, and data; applicability of geostatistical estimation methods to scalar rock properties; comments on in-situ stress at the Carwynnen test mine and the state of stress in the British Isles. (U.K.)

  3. A Generalizable Methodology for Quantifying User Satisfaction

    Science.gov (United States)

    Huang, Te-Yuan; Chen, Kuan-Ta; Huang, Polly; Lei, Chin-Laung

    Quantifying user satisfaction is essential, because the results can help service providers deliver better services. In this work, we propose a generalizable methodology, based on survival analysis, to quantify user satisfaction in terms of session times, i. e., the length of time users stay with an application. Unlike subjective human surveys, our methodology is based solely on passive measurement, which is more cost-efficient and better able to capture subconscious reactions. Furthermore, by using session times, rather than a specific performance indicator, such as the level of distortion of voice signals, the effects of other factors like loudness and sidetone, can also be captured by the developed models. Like survival analysis, our methodology is characterized by low complexity and a simple model-developing process. The feasibility of our methodology is demonstrated through case studies of ShenZhou Online, a commercial MMORPG in Taiwan, and the most prevalent VoIP application in the world, namely Skype. Through the model development process, we can also identify the most significant performance factors and their impacts on user satisfaction and discuss how they can be exploited to improve user experience and optimize resource allocation.

  4. Effort versus Reward: Preparing Samples for Fungal Community Characterization in High-Throughput Sequencing Surveys of Soils.

    Directory of Open Access Journals (Sweden)

    Zewei Song

    Full Text Available Next generation fungal amplicon sequencing is being used with increasing frequency to study fungal diversity in various ecosystems; however, the influence of sample preparation on the characterization of fungal community is poorly understood. We investigated the effects of four procedural modifications to library preparation for high-throughput sequencing (HTS. The following treatments were considered: 1 the amount of soil used in DNA extraction, 2 the inclusion of additional steps (freeze/thaw cycles, sonication, or hot water bath incubation in the extraction procedure, 3 the amount of DNA template used in PCR, and 4 the effect of sample pooling, either physically or computationally. Soils from two different ecosystems in Minnesota, USA, one prairie and one forest site, were used to assess the generality of our results. The first three treatments did not significantly influence observed fungal OTU richness or community structure at either site. Physical pooling captured more OTU richness compared to individual samples, but total OTU richness at each site was highest when individual samples were computationally combined. We conclude that standard extraction kit protocols are well optimized for fungal HTS surveys, but because sample pooling can significantly influence OTU richness estimates, it is important to carefully consider the study aims when planning sampling procedures.

  5. A PROMPT METHODOLOGY TO GEOREFERENCE COMPLEX HYPOGEA ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    S. Troisi

    2017-02-01

    Full Text Available Actually complex underground structures and facilities occupy a wide space in our cities, most of them are often unsurveyed; cable duct, drainage system are not exception. Furthermore, several inspection operations are performed in critical air condition, that do not allow or make more difficult a conventional survey. In this scenario a prompt methodology to survey and georeferencing such facilities is often indispensable. A visual based approach was proposed in this paper; such methodology provides a 3D model of the environment and the path followed by the camera using the conventional photogrammetric/Structure from motion software tools. The key-role is played by the lens camera; indeed, a fisheye system was employed to obtain a very wide field of view (FOV and therefore high overlapping among the frames. The camera geometry is in according to a forward motion along the axis camera. Consequently, to avoid instability of bundle adjustment algorithm a preliminary calibration of camera was carried out. A specific case study was reported and the accuracy achieved.

  6. a Prompt Methodology to Georeference Complex Hypogea Environments

    Science.gov (United States)

    Troisi, S.; Baiocchi, V.; Del Pizzo, S.; Giannone, F.

    2017-02-01

    Actually complex underground structures and facilities occupy a wide space in our cities, most of them are often unsurveyed; cable duct, drainage system are not exception. Furthermore, several inspection operations are performed in critical air condition, that do not allow or make more difficult a conventional survey. In this scenario a prompt methodology to survey and georeferencing such facilities is often indispensable. A visual based approach was proposed in this paper; such methodology provides a 3D model of the environment and the path followed by the camera using the conventional photogrammetric/Structure from motion software tools. The key-role is played by the lens camera; indeed, a fisheye system was employed to obtain a very wide field of view (FOV) and therefore high overlapping among the frames. The camera geometry is in according to a forward motion along the axis camera. Consequently, to avoid instability of bundle adjustment algorithm a preliminary calibration of camera was carried out. A specific case study was reported and the accuracy achieved.

  7. Combining users' activity survey and simulators to evaluate human activity recognition systems.

    Science.gov (United States)

    Azkune, Gorka; Almeida, Aitor; López-de-Ipiña, Diego; Chen, Liming

    2015-04-08

    Evaluating human activity recognition systems usually implies following expensive and time-consuming methodologies, where experiments with humans are run with the consequent ethical and legal issues. We propose a novel evaluation methodology to overcome the enumerated problems, which is based on surveys for users and a synthetic dataset generator tool. Surveys allow capturing how different users perform activities of daily living, while the synthetic dataset generator is used to create properly labelled activity datasets modelled with the information extracted from surveys. Important aspects, such as sensor noise, varying time lapses and user erratic behaviour, can also be simulated using the tool. The proposed methodology is shown to have very important advantages that allow researchers to carry out their work more efficiently. To evaluate the approach, a synthetic dataset generated following the proposed methodology is compared to a real dataset computing the similarity between sensor occurrence frequencies. It is concluded that the similarity between both datasets is more than significant.

  8. Combining Users’ Activity Survey and Simulators to Evaluate Human Activity Recognition Systems

    Directory of Open Access Journals (Sweden)

    Gorka Azkune

    2015-04-01

    Full Text Available Evaluating human activity recognition systems usually implies following expensive and time-consuming methodologies, where experiments with humans are run with the consequent ethical and legal issues. We propose a novel evaluation methodology to overcome the enumerated problems, which is based on surveys for users and a synthetic dataset generator tool. Surveys allow capturing how different users perform activities of daily living, while the synthetic dataset generator is used to create properly labelled activity datasets modelled with the information extracted from surveys. Important aspects, such as sensor noise, varying time lapses and user erratic behaviour, can also be simulated using the tool. The proposed methodology is shown to have very important advantages that allow researchers to carry out their work more efficiently. To evaluate the approach, a synthetic dataset generated following the proposed methodology is compared to a real dataset computing the similarity between sensor occurrence frequencies. It is concluded that the similarity between both datasets is more than significant.

  9. Combining Users' Activity Survey and Simulators to Evaluate Human Activity Recognition Systems

    Science.gov (United States)

    Azkune, Gorka; Almeida, Aitor; López-de-Ipiña, Diego; Chen, Liming

    2015-01-01

    Evaluating human activity recognition systems usually implies following expensive and time-consuming methodologies, where experiments with humans are run with the consequent ethical and legal issues. We propose a novel evaluation methodology to overcome the enumerated problems, which is based on surveys for users and a synthetic dataset generator tool. Surveys allow capturing how different users perform activities of daily living, while the synthetic dataset generator is used to create properly labelled activity datasets modelled with the information extracted from surveys. Important aspects, such as sensor noise, varying time lapses and user erratic behaviour, can also be simulated using the tool. The proposed methodology is shown to have very important advantages that allow researchers to carry out their work more efficiently. To evaluate the approach, a synthetic dataset generated following the proposed methodology is compared to a real dataset computing the similarity between sensor occurrence frequencies. It is concluded that the similarity between both datasets is more than significant. PMID:25856329

  10. Survey of the prevalence and methodology of quality assurance for B-mode ultrasound image quality among veterinary sonographers.

    Science.gov (United States)

    Hoscheit, Larry P; Heng, Hock Gan; Lim, Chee Kin; Weng, Hsin-Yi

    2018-05-01

    Image quality in B-mode ultrasound is important as it reflects the diagnostic accuracy and diagnostic information provided during clinical scanning. Quality assurance programs for B-mode ultrasound systems/components are comprised of initial quality acceptance testing and subsequent regularly scheduled quality control testing. The importance of quality assurance programs for B-mode ultrasound image quality using ultrasound phantoms is well documented in the human medical and medical physics literature. The purpose of this prospective, cross-sectional, survey study was to determine the prevalence and methodology of quality acceptance testing and quality control testing of image quality for ultrasound system/components among veterinary sonographers. An online electronic survey was sent to 1497 members of veterinary imaging organizations: the American College of Veterinary Radiology, the Veterinary Ultrasound Society, and the European Association of Veterinary Diagnostic Imaging, and a total of 167 responses were received. The results showed that the percentages of veterinary sonographers performing quality acceptance testing and quality control testing are 42% (64/151; 95% confidence interval 34-52%) and 26% (40/156: 95% confidence interval 19-33%) respectively. Of the respondents who claimed to have quality acceptance testing or quality control testing of image quality in place for their ultrasound system/components, 0% have performed quality acceptance testing or quality control testing correctly (quality acceptance testing 95% confidence interval: 0-6%, quality control testing 95% confidence interval: 0-11%). Further education and guidelines are recommended for veterinary sonographers in the area of quality acceptance testing and quality control testing for B-mode ultrasound equipment/components. © 2018 American College of Veterinary Radiology.

  11. National nutrition surveys in Europe: a review on the current status in the 53 countries of the WHO European region.

    Science.gov (United States)

    Rippin, Holly L; Hutchinson, Jayne; Evans, Charlotte E L; Jewell, Jo; Breda, Joao J; Cade, Janet E

    2018-01-01

    The objectives of this study were (1) to determine the coverage of national nutrition surveys in the 53 countries monitored by the World Health Organization (WHO) Regional Office for Europe and identify gaps in provision, (2) to describe relevant survey attributes and (3) to check whether energy and nutrients are reported with a view to providing information for evidence-based nutrition policy planning. Dietary survey information was gathered using three methods: (1) direct email to survey authors and other relevant contacts, (2) systematic review of literature databases and (3) general web-based searches. Survey characteristics relating to time frame, sampling and dietary methodology and nutrients reported were tabled from all relevant surveys found since 1990. Fifty-three countries of the WHO Regional Office for Europe, which have need for an overview of dietary surveys across the life course. European individuals (adults and children) in national diet surveys. A total of 109 nationally representative dietary surveys undertaken post-1990 were found across 34 countries. Of these, 78 surveys from 33 countries were found post-2000, and of these, 48 surveys from 27 countries included children and 60 surveys from 30 countries included adults. No nationally representative surveys were found for 19 of 53 countries, mainly from Central and Eastern Europe. Multiple 24hr recall and food diaries were the most common dietary assessment methods. Only 22 countries reported energy and nutrient intakes from post-2000 surveys; macronutrients were more widely reported than micronutrients. Less than two-thirds of WHO Europe countries have nationally representative diet surveys, mainly collected post-2000. The main availability gaps lie in Central and Eastern European countries, where nutrition policies may therefore lack an appropriate evidence base. Dietary methodological differences may limit the scope for inter-country comparisons.

  12. National nutrition surveys in Europe: a review on the current status in the 53 countries of the WHO European region

    Directory of Open Access Journals (Sweden)

    Holly L. Rippin

    2018-04-01

    Full Text Available Objectives: The objectives of this study were (1 to determine the coverage of national nutrition surveys in the 53 countries monitored by the World Health Organization (WHO Regional Office for Europe and identify gaps in provision, (2 to describe relevant survey attributes and (3 to check whether energy and nutrients are reported with a view to providing information for evidence-based nutrition policy planning. Design: Dietary survey information was gathered using three methods: (1 direct email to survey authors and other relevant contacts, (2 systematic review of literature databases and (3 general web-based searches. Survey characteristics relating to time frame, sampling and dietary methodology and nutrients reported were tabled from all relevant surveys found since 1990. Setting: Fifty-three countries of the WHO Regional Office for Europe, which have need for an overview of dietary surveys across the life course. Subjects: European individuals (adults and children in national diet surveys. Results: A total of 109 nationally representative dietary surveys undertaken post-1990 were found across 34 countries. Of these, 78 surveys from 33 countries were found post-2000, and of these, 48 surveys from 27 countries included children and 60 surveys from 30 countries included adults. No nationally representative surveys were found for 19 of 53 countries, mainly from Central and Eastern Europe. Multiple 24hr recall and food diaries were the most common dietary assessment methods. Only 22 countries reported energy and nutrient intakes from post-2000 surveys; macronutrients were more widely reported than micronutrients. Conclusions: Less than two-thirds of WHO Europe countries have nationally representative diet surveys, mainly collected post-2000. The main availability gaps lie in Central and Eastern European countries, where nutrition policies may therefore lack an appropriate evidence base. Dietary methodological differences may limit the scope for

  13. A Methodology To Incorporate The Safety Culture Into Probabilistic Safety Assessments

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sunghyun; Kim, Namyeong; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of)

    2015-10-15

    In order to incorporate organizational factors into PSA, a methodology needs to be developed. Using the AHP to weigh organizational factors as well as the SLIM to rate those factors, a methodology is introduced in this study. The safety issues related to nuclear safety culture have occurred increasingly. The quantification tool has to be developed in order to include the organizational factor into Probabilistic Safety Assessments. In this study, the state-of-the-art for the organizational evaluation methodologies has been surveyed. This study includes the research for organizational factors, maintenance process, maintenance process analysis models, a quantitative methodology using Analytic Hierarchy Process, Success Likelihood Index Methodology. The purpose of this study is to develop a methodology to incorporate the safety culture into PSA for obtaining more objective risk than before. The organizational factor considered in nuclear safety culture might affect the potential risk of human error and hardware-failure. The safety culture impact index to monitor the plant safety culture can be assessed by applying the developed methodology into a nuclear power plant.

  14. A Methodology To Incorporate The Safety Culture Into Probabilistic Safety Assessments

    International Nuclear Information System (INIS)

    Park, Sunghyun; Kim, Namyeong; Jae, Moosung

    2015-01-01

    In order to incorporate organizational factors into PSA, a methodology needs to be developed. Using the AHP to weigh organizational factors as well as the SLIM to rate those factors, a methodology is introduced in this study. The safety issues related to nuclear safety culture have occurred increasingly. The quantification tool has to be developed in order to include the organizational factor into Probabilistic Safety Assessments. In this study, the state-of-the-art for the organizational evaluation methodologies has been surveyed. This study includes the research for organizational factors, maintenance process, maintenance process analysis models, a quantitative methodology using Analytic Hierarchy Process, Success Likelihood Index Methodology. The purpose of this study is to develop a methodology to incorporate the safety culture into PSA for obtaining more objective risk than before. The organizational factor considered in nuclear safety culture might affect the potential risk of human error and hardware-failure. The safety culture impact index to monitor the plant safety culture can be assessed by applying the developed methodology into a nuclear power plant

  15. Reduction in alert fatigue in an assisted electronic prescribing system, through the Lean Six Sigma methodology.

    Science.gov (United States)

    Cuéllar Monreal, Mª Jesús; Reig Aguado, Jorge; Font Noguera, Isabel; Poveda Andrés, José Luis

    2017-01-01

    To reduce the alert fatigue in our Assisted Electronic Prescribing System (AEPS), through the Lean Six Sigma (LSS) methodology. An observational (transversal) and retrospective study, in a general hospital with 850 beds and AEPS. The LSS methodology was followed in order to evaluate the alert fatigue situation in the AEPS system, to implement improvements, and to assess outcomes. The alerts generated during two trimesters studied (before and after the intervention) were analyzed. In order to measure the qualitative indicators, the most frequent alert types were analyzed, as well as the molecules responsible for over 50% of each type of alert. The action by the prescriber was analyzed in a sample of 496 prescriptions that generated such alerts. For each type of alert and molecule, there was a prioritization of the improvements to be implemented according to the alert generated and its quality. A second survey evaluated the pharmacist action for the alerts most highly valued by physicians. The problem, the objective, the work team and the project schedule were defined. A survey was designed in order to understand the opinion of the client about the alert system in the program. Based on the surveys collected (n = 136), the critical characteristics and the quanti/qualitative indicators were defined. Sixty (60) fields in the alert system were modified, corresponding to 32 molecules, and this led to a 28% reduction in the total number of alerts. Regarding quality indicators, false po sitive results were reduced by 25% (p < 0.05), 100% of those alerts ignored with justification were sustained, and there were no significant differences in user adherence to the system. The project improvements and outcomes were reviewed by the work team. LSS methodology has demonstrated being a valid tool for the quantitative and qualitative improvement of the alert system in an Assisted Electronic Prescription Program, thus reducing alert fatigue. Copyright AULA MEDICA EDICIONES 2014

  16. Point process models for spatio-temporal distance sampling data from a large-scale survey of blue whales

    KAUST Repository

    Yuan, Yuan; Bachl, Fabian E.; Lindgren, Finn; Borchers, David L.; Illian, Janine B.; Buckland, Stephen T.; Rue, Haavard; Gerrodette, Tim

    2017-01-01

    Distance sampling is a widely used method for estimating wildlife population abundance. The fact that conventional distance sampling methods are partly design-based constrains the spatial resolution at which animal density can be estimated using these methods. Estimates are usually obtained at survey stratum level. For an endangered species such as the blue whale, it is desirable to estimate density and abundance at a finer spatial scale than stratum. Temporal variation in the spatial structure is also important. We formulate the process generating distance sampling data as a thinned spatial point process and propose model-based inference using a spatial log-Gaussian Cox process. The method adopts a flexible stochastic partial differential equation (SPDE) approach to model spatial structure in density that is not accounted for by explanatory variables, and integrated nested Laplace approximation (INLA) for Bayesian inference. It allows simultaneous fitting of detection and density models and permits prediction of density at an arbitrarily fine scale. We estimate blue whale density in the Eastern Tropical Pacific Ocean from thirteen shipboard surveys conducted over 22 years. We find that higher blue whale density is associated with colder sea surface temperatures in space, and although there is some positive association between density and mean annual temperature, our estimates are consistent with no trend in density across years. Our analysis also indicates that there is substantial spatially structured variation in density that is not explained by available covariates.

  17. Point process models for spatio-temporal distance sampling data from a large-scale survey of blue whales

    KAUST Repository

    Yuan, Yuan

    2017-12-28

    Distance sampling is a widely used method for estimating wildlife population abundance. The fact that conventional distance sampling methods are partly design-based constrains the spatial resolution at which animal density can be estimated using these methods. Estimates are usually obtained at survey stratum level. For an endangered species such as the blue whale, it is desirable to estimate density and abundance at a finer spatial scale than stratum. Temporal variation in the spatial structure is also important. We formulate the process generating distance sampling data as a thinned spatial point process and propose model-based inference using a spatial log-Gaussian Cox process. The method adopts a flexible stochastic partial differential equation (SPDE) approach to model spatial structure in density that is not accounted for by explanatory variables, and integrated nested Laplace approximation (INLA) for Bayesian inference. It allows simultaneous fitting of detection and density models and permits prediction of density at an arbitrarily fine scale. We estimate blue whale density in the Eastern Tropical Pacific Ocean from thirteen shipboard surveys conducted over 22 years. We find that higher blue whale density is associated with colder sea surface temperatures in space, and although there is some positive association between density and mean annual temperature, our estimates are consistent with no trend in density across years. Our analysis also indicates that there is substantial spatially structured variation in density that is not explained by available covariates.

  18. Ochratoxin A in raisins and currants: basic extraction procedure used in two small marketing surveys of the occurrence and control of the heterogeneity of the toxins in samples.

    Science.gov (United States)

    Möller, T E; Nyberg, M

    2003-11-01

    A basic extraction procedure for analysis of ochratoxin A (OTA) in currants and raisins is described, as well as the occurrence of OTA and a control of heterogeneity of the toxin in samples bought for two small marketing surveys 1999/2000 and 2001/02. Most samples in the surveys were divided into two subsamples that were individually prepared as slurries and analysed separately. The limit of quantification for the method was estimated as 0.1 microg kg(-1) and recoveries of 85, 90 and 115% were achieved in recovery experiments at 10, 5 and 0.1 microg kg(-1), respectively. Of all 118 subsamples analysed in the surveys, 96 (84%) contained ochratoxin A at levels above the quantification level and five samples (4%) contained more than the European Community legislation of 10 microg kg(-1). The OTA concentrations found in the first survey were in the range Big differences were often achieved between individual subsamples of the original sample, which indicate a wide heterogeneous distribution of the toxin. Data from the repeatability test as well as recovery experiments from the same slurries showed that preparation of slurries as described here seemed to give a homogeneous and representative sample. The extraction with the basic sodium bicarbonate-methanol mixture used in the surveys gave similar or somewhat higher OTA values on some samples tested in a comparison with a weak phosphoric acid water-methanol extraction mixture.

  19. On a Modular Approach to the Design of Integrated Social Surveys

    Directory of Open Access Journals (Sweden)

    Ioannidis Evangelos

    2016-06-01

    Full Text Available This article considers a modular approach to the design of integrated social surveys. The approach consists of grouping variables into ‘modules’, each of which is then allocated to one or more ‘instruments’. Each instrument is then administered to a random sample of population units, and each sample unit responds to all modules of the instrument. This approach offers a way of designing a system of integrated social surveys that balances the need to limit the cost and the need to obtain sufficient information. The allocation of the modules to instruments draws on the methodology of split questionnaire designs. The composition of the instruments, that is, how the modules are allocated to instruments, and the corresponding sample sizes are obtained as a solution to an optimisation problem. This optimisation involves minimisation of respondent burden and data collection cost, while respecting certain design constraints usually encountered in practice. These constraints may include, for example, the level of precision required and dependencies between the variables. We propose using a random search algorithm to find approximate optimal solutions to this problem. The algorithm is proved to fulfil conditions that ensure convergence to the global optimum and can also produce an efficient design for a split questionnaire.

  20. Rationale, design, methodology and sample characteristics for the Vietnam pre-conceptual micronutrient supplementation trial (PRECONCEPT: a randomized controlled study

    Directory of Open Access Journals (Sweden)

    Nguyen Phuong H

    2012-10-01

    Full Text Available Abstract Background Low birth weight and maternal anemia remain intractable problems in many developing countries. The adequacy of the current strategy of providing iron-folic acid (IFA supplements only during pregnancy has been questioned given many women enter pregnancy with poor iron stores, the substantial micronutrient demand by maternal and fetal tissues, and programmatic issues related to timing and coverage of prenatal care. Weekly IFA supplementation for women of reproductive age (WRA improves iron status and reduces the burden of anemia in the short term, but few studies have evaluated subsequent pregnancy and birth outcomes. The Preconcept trial aims to determine whether pre-pregnancy weekly IFA or multiple micronutrient (MM supplementation will improve birth outcomes and maternal and infant iron status compared to the current practice of prenatal IFA supplementation only. This paper provides an overview of study design, methodology and sample characteristics from baseline survey data and key lessons learned. Methods/design We have recruited 5011 WRA in a double-blind stratified randomized controlled trial in rural Vietnam and randomly assigned them to receive weekly supplements containing either: 1 2800 μg folic acid 2 60 mg iron and 2800 μg folic acid or 3 MM. Women who become pregnant receive daily IFA, and are being followed through pregnancy, delivery, and up to three months post-partum. Study outcomes include birth outcomes and maternal and infant iron status. Data are being collected on household characteristics, maternal diet and mental health, anthropometry, infant feeding practices, morbidity and compliance. Discussion The study is timely and responds to the WHO Global Expert Consultation which identified the need to evaluate the long term benefits of weekly IFA and MM supplementation in WRA. Findings will generate new information to help guide policy and programs designed to reduce the burden of anemia in women and

  1. Evaluation of carbon monoxide in blood samples from the second health and nutrition survey. Progress report No. 1

    Energy Technology Data Exchange (ETDEWEB)

    Radford, E.P.

    1976-01-01

    This is a study of carbon monoxide (CO) in the blood of human subjects participating in the Second National Health and Nutrition Survey (HANES II), a detailed study of health indicators in sample populations of many communities throughout the U.S. The purpose of this aspect of the survey is to evaluate the levels of blood carboxyhemoglobin in normal individuals of all ages in typical U.S. communities, from whom accurate histories and clinical studies are available. This report gives results of the first of three years of analyses. A careful calibration of the analytical method has been completed, and more than 3000 blood samples have been analyzed. Although smoking histories are not yet available to permit evaluation of carboxyhemoglobin in non-smokers, in children under 12 years of age, blood COHb has been found to be consistently low, with less than 3% greater than 1.5% COHb. These preliminary results suggest that urban exposure to carbon monoxide among the general population is not now significant in the U.S., at least during the period of these early examinations.

  2. A performance assessment methodology for low-level waste facilities

    International Nuclear Information System (INIS)

    Kozak, M.W.; Chu, M.S.Y.; Mattingly, P.A.

    1990-07-01

    A performance assessment methodology has been developed for use by the US Nuclear Regulatory Commission in evaluating license applications for low-level waste disposal facilities. This report provides a summary of background reports on the development of the methodology and an overview of the models and codes selected for the methodology. The overview includes discussions of the philosophy and structure of the methodology and a sequential procedure for applying the methodology. Discussions are provided of models and associated assumptions that are appropriate for each phase of the methodology, the goals of each phase, data required to implement the models, significant sources of uncertainty associated with each phase, and the computer codes used to implement the appropriate models. In addition, a sample demonstration of the methodology is presented for a simple conceptual model. 64 refs., 12 figs., 15 tabs

  3. The efficacy of respondent-driven sampling for the health assessment of minority populations.

    Science.gov (United States)

    Badowski, Grazyna; Somera, Lilnabeth P; Simsiman, Brayan; Lee, Hye-Ryeon; Cassel, Kevin; Yamanaka, Alisha; Ren, JunHao

    2017-10-01

    Respondent driven sampling (RDS) is a relatively new network sampling technique typically employed for hard-to-reach populations. Like snowball sampling, initial respondents or "seeds" recruit additional respondents from their network of friends. Under certain assumptions, the method promises to produce a sample independent from the biases that may have been introduced by the non-random choice of "seeds." We conducted a survey on health communication in Guam's general population using the RDS method, the first survey that has utilized this methodology in Guam. It was conducted in hopes of identifying a cost-efficient non-probability sampling strategy that could generate reasonable population estimates for both minority and general populations. RDS data was collected in Guam in 2013 (n=511) and population estimates were compared with 2012 BRFSS data (n=2031) and the 2010 census data. The estimates were calculated using the unweighted RDS sample and the weighted sample using RDS inference methods and compared with known population characteristics. The sample size was reached in 23days, providing evidence that the RDS method is a viable, cost-effective data collection method, which can provide reasonable population estimates. However, the results also suggest that the RDS inference methods used to reduce bias, based on self-reported estimates of network sizes, may not always work. Caution is needed when interpreting RDS study findings. For a more diverse sample, data collection should not be conducted in just one location. Fewer questions about network estimates should be asked, and more careful consideration should be given to the kind of incentives offered to participants. Copyright © 2017. Published by Elsevier Ltd.

  4. Methodological issues associated with collecting sensitive information over the telephone - experience from an Australian non-suicidal self-injury (NSSI prevalence study

    Directory of Open Access Journals (Sweden)

    Fullerton Simon

    2011-02-01

    Full Text Available Abstract Background Collecting population data on sensitive issues such as non-suicidal self-injury (NSSI is problematic. Case note audits or hospital/clinic based presentations only record severe cases and do not distinguish between suicidal and non-suicidal intent. Community surveys have largely been limited to school and university students, resulting in little much needed population-based data on NSSI. Collecting these data via a large scale population survey presents challenges to survey methodologists. This paper addresses the methodological issues associated with collecting this type of data via CATI. Methods An Australia-wide population survey was funded by the Australian Government to determine prevalence estimates of NSSI and associations, predictors, relationships to suicide attempts and suicide ideation, and outcomes. Computer assisted telephone interviewing (CATI on a random sample of the Australian population aged 10+ years of age from randomly selected households, was undertaken. Results Overall, from 31,216 eligible households, 12,006 interviews were undertaken (response rate 38.5%. The 4-week prevalence of NSSI was 1.1% (95% ci 0.9-1.3% and lifetime prevalence was 8.1% (95% ci 7.6-8.6. Methodological concerns and challenges in regard to collection of these data included extensive interviewer training and post interview counselling. Ethical considerations, especially with children as young as 10 years of age being asked sensitive questions, were addressed prior to data collection. The solution required a large amount of information to be sent to each selected household prior to the telephone interview which contributed to a lower than expected response rate. Non-coverage error caused by the population of interest being highly mobile, homeless or institutionalised was also a suspected issue in this low prevalence condition. In many circumstances the numbers missing from the sampling frame are small enough to not cause worry

  5. A call to improve sampling methodology and reporting in young novice driver research.

    Science.gov (United States)

    Scott-Parker, B; Senserrick, T

    2017-02-01

    Young drivers continue to be over-represented in road crash fatalities despite a multitude of research, communication and intervention. Evidence-based improvement depends to a great extent upon research methodology quality and its reporting, with known limitations in the peer-review process. The aim of the current research was to review the scope of research methodologies applied in 'young driver' and 'teen driver' research and their reporting in four peer-review journals in the field between January 2006 and December 2013. In total, 806 articles were identified and assessed. Reporting omissions included participant gender (11% of papers), response rates (49%), retention rates (39%) and information regarding incentives (44%). Greater breadth and specific improvements in study designs and reporting are thereby identified as a means to further advance the field. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  6. Geochemical drainage surveys for uranium: sampling and analytical methods based on trial surveys in Pennsylvania

    International Nuclear Information System (INIS)

    Rose, A.W.; Keith, M.L.; Suhr, N.H.

    1976-01-01

    Geochemical surveys near sandstone-type uranium prospects in northeastern and north-central Pennsylvania show that the deposits can be detected by carefully planned stream sediment surveys, but not by stream water surveys. Stream waters at single sites changed in U content by x10 to 50 during the 18 months of our studies, and even near known prospects, contain less than 0.2 ppB U most of the time. Uranium extractable from stream sediment by acetic acid--H 2 O 2 provides useful contrast between mineralized and nonmineralized drainages of a square mile or less; total U in sediment does not. High organic material results in increased U content of sediments and must be corrected. Changes in U content of sediment with time reach a maximum of x3 and appear to be of short duration. A sediment of about 200 mi 2 near Jim Thorpe detects anomalies extending over several square miles near known occurrences and a second anomaly about two miles northeast of Penn Haven Jct. A similar survey in Lycoming-Sullivan Counties shows anomalous zones near known prospects of the Beaver Lake area and northwest of Muncy Creek. As, Mn, Pb, and V are enriched in the mineralized zones, and perhaps in surrounding halo zones, but do not appear to be pathfinder elements useful for reconnaissance exploration

  7. Using Social Media and Targeted Snowball Sampling to Survey a Hard-to-reach Population: A Case Study

    Directory of Open Access Journals (Sweden)

    Gary Dusek

    2015-08-01

    Full Text Available Response rates to the academic surveys used in quantitative research are decreasing and have been for several decades among both individuals and organizations. Given this trend, providing doctoral students an opportunity to complete their dissertations in a timely and cost effective manner may necessitate identifying more innovative and relevant ways to collect data while maintaining appropriate research standards and rigor. The case of a research study is presented which describes the data collection process used to survey a hard-to-reach population. It details the use of social media, in this case LinkedIn, to facilitate the distribution of the web-based survey. A roadmap to illustrate how this data collection process unfolded is presented, as well as several “lessons learned” during this journey. An explanation of the considerations that impacted the sampling design is provided. The goal of this case study is to provide researchers, including doctoral students, with realistic expectations and an awareness of the benefits and risks associated with the use of this method of data collection.

  8. Latest developments on safety analysis methodologies at the Juzbado plant

    International Nuclear Information System (INIS)

    Zurron-Cifuentes, Oscar; Ortiz-Trujillo, Diego; Blanco-Fernandez, Luis A.

    2010-01-01

    Over the last few years the Juzbado Plant has developed and implemented several analysis methodologies to cope with specific issues regarding safety management. This paper describes the three most outstanding of them, so as to say, the Integrated Safety Analysis (ISA) project, the adaptation of the MARSSIM methodology for characterization surveys of radioactive contamination spots, and the programme for the Systematic Review of the Operational Conditions of the Safety Systems (SROCSS). Several reasons motivated the decision to implement such methodologies, such as Regulator requirements, operational experience and of course, the strong commitment of ENUSA to maintain the highest standards of nuclear industry on all the safety relevant activities. In this context, since 2004 ENUSA is undertaking the ISA project, which consists on a systematic examination of plant's processes, equipment, structures and personnel activities to ensure that all relevant hazards that could result in unacceptable consequences have been adequately evaluated and the appropriate protective measures have been identified. On the other hand and within the framework of a current programme to ensure the absence of radioactive contamination spots on unintended areas, the MARSSIM methodology is being applied as a tool to conduct the radiation surveys and investigation of potentially contaminated areas. Finally, the SROCSS programme was initiated earlier this year 2009 to assess the actual operating conditions of all the systems with safety relevance, aiming to identify either potential non-conformities or areas for improvement in order to ensure their high performance after years of operation. The following paragraphs describe the key points related to these three methodologies as well as an outline of the results obtained so far. (authors)

  9. Annual Omnibus Survey: A survey of life in Qatar 2014

    OpenAIRE

    Diop, Abdoulaye; Gengler, Justin John; Khan, Mohammad N.; Traugott, Michael; Elawad, Elmogiera Fadlallh; Al Ansari, Majed; Le, Kien T.; El-Maghraby, Engi; Elkassem, Rima Charbaji; Qutteina, Yara; Al Khulaifi, Buthaina; Nasrallah, Catherine; Al Subaey, Mohammed; Mustafa, Semsia Al-Ali; Alqassass, Haneen

    2015-01-01

    This Executive Summary presents the highlights of the 2014 Omnibus survey, the fourth in a series of Omnibus surveys since 2010. The surveys were carried out by the Social and Economic Survey Research Institute (SESRI) of Qatar University. Each Omnibus survey interviews a large and representative sample of Qatari citizens, resident expatriates and laborers. In these surveys, we asked a number of questions covering several topics of importance to Qatari society, including their ...

  10. Final report of the documentation of the methodology designed by PESENCA for the development of local concepts of energy supply

    International Nuclear Information System (INIS)

    1991-01-01

    A report is presented about the methodology designed by PESENCA for the development of local concepts of energy supply in the Atlantic Costa of Colombia; are includes localization, executor institutions, their organization, the global studies and database in the different projects. It is indicated the selection of investigation and planning areas, the consulted entities and the design of methodological instruments as forms of surveys control. The sampling strategies and the design of preparation of databases are described. It is indicated the selection, training and the specific activities for each area like the delimitation of the work area, the design of the work and the field work; equally the analysis of results in electric power terms, firewood and rest of biomass. An analysis of the socioeconomic situation of the area is made and concepts are elaborated on energy solutions

  11. Lifting the veil: a typological survey of the methodological features of Islamic ethical reasoning on biomedical issues.

    Science.gov (United States)

    Abdur-Rashid, Khalil; Furber, Steven Woodward; Abdul-Basser, Taha

    2013-04-01

    We survey the meta-ethical tools and institutional processes that traditional Islamic ethicists apply when deliberating on bioethical issues. We present a typology of these methodological elements, giving particular attention to the meta-ethical techniques and devices that traditional Islamic ethicists employ in the absence of decisive or univocal authoritative texts or in the absence of established transmitted cases. In describing how traditional Islamic ethicists work, we demonstrate that these experts possess a variety of discursive tools. We find that the ethical responsa-i.e., the products of the application of the tools that we describe-are generally characterized by internal consistency. We also conclude that Islamic ethical reasoning on bioethical issues, while clearly scripture-based, is also characterized by strong consequentialist elements and possesses clear principles-based characteristics. The paper contributes to the study of bioethics by familiarizing non-specialists in Islamic ethics with the role, scope, and applicability of key Islamic ethical concepts, such as "aims" (maqāṣid), "universals" (kulliyyāt), "interest" (maṣlaḥa), "maxims" (qawā`id), "controls" (ḍawābit), "differentiators" (furūq), "preponderization" (tarjīḥ), and "extension" (tafrī`).

  12. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods.

    Science.gov (United States)

    Kleinschmidt, R; Watson, D

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km(2)), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h(-1) (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  13. Hepatitis C bio-behavioural surveys in people who inject drugs-a systematic review of sensitivity to the theoretical assumptions of respondent driven sampling.

    Science.gov (United States)

    Buchanan, Ryan; Khakoo, Salim I; Coad, Jonathan; Grellier, Leonie; Parkes, Julie

    2017-07-11

    New, more effective and better-tolerated therapies for hepatitis C (HCV) have made the elimination of HCV a feasible objective. However, for this to be achieved, it is necessary to have a detailed understanding of HCV epidemiology in people who inject drugs (PWID). Respondent-driven sampling (RDS) can provide prevalence estimates in hidden populations such as PWID. The aims of this systematic review are to identify published studies that use RDS in PWID to measure the prevalence of HCV, and compare each study against the STROBE-RDS checklist to assess their sensitivity to the theoretical assumptions underlying RDS. Searches were undertaken in accordance with PRISMA systematic review guidelines. Included studies were English language publications in peer-reviewed journals, which reported the use of RDS to recruit PWID to an HCV bio-behavioural survey. Data was extracted under three headings: (1) survey overview, (2) survey outcomes, and (3) reporting against selected STROBE-RDS criteria. Thirty-one studies met the inclusion criteria. They varied in scale (range 1-15 survey sites) and the sample sizes achieved (range 81-1000 per survey site) but were consistent in describing the use of standard RDS methods including: seeds, coupons and recruitment incentives. Twenty-seven studies (87%) either calculated or reported the intention to calculate population prevalence estimates for HCV and two used RDS data to calculate the total population size of PWID. Detailed operational and analytical procedures and reporting against selected criteria from the STROBE-RDS checklist varied between studies. There were widespread indications that sampling did not meet the assumptions underlying RDS, which led to two studies being unable to report an estimated HCV population prevalence in at least one survey location. RDS can be used to estimate a population prevalence of HCV in PWID and estimate the PWID population size. Accordingly, as a single instrument, it is a useful tool for

  14. High prevalence of thiamine (vitamin B1) deficiency in early childhood among a nationally representative sample of Cambodian women of childbearing age and their children

    DEFF Research Database (Denmark)

    Whitfield, Kyly C; Smith, Geoffry; Chamnan, Chhoun

    2017-01-01

    the thiamine status (measured as erythrocyte thiamine diphosphate concentrations; eThDP) among a representative sample of Cambodian women of childbearing age (15-49 y) and their young children (6-69 mo). METHODOLOGY/PRINCIPLE FINDINGS: Samples for this cross-sectional analysis were collected as part...... of a national micronutrient survey linked to the Cambodian Demographic and Health Survey (CDHS) 2014. One-sixth of households taking part in the CDHS were randomly selected and re-visited for additional blood sampling for eThDP analysis (719 women and 761 children). Thiamine status was assessed using different...... cut-offs from literature. Women were mean (SD) 30 (6) y, and children (46% girls) were 41 (17) mo. Women had lower mean (95% CI) eThDP of 150 nmol/L (146-153) compared to children, 174 nmol/L (171-179; P

  15. Experimental study of a methodology for Fission-track Dating without neutron irradiation

    International Nuclear Information System (INIS)

    Hadler, J.C.; Iunes, P.J.; Tello, C.A.; Chemale, F.; Kawashita, K.; Curvo, E.A.C.; Santos, F.G.S.; Gasparini, T.E.; Moreira, P.A.F.P.; Guedes, S.

    2009-01-01

    To carry out the dating by the Fission Track Method (FTM) the international community that works with this method employs methodologies in which the mineral to be dated must be irradiated with neutrons. Such irradiation, performed in a nuclear reactor, demand a relatively long waiting time so that the activity of the sample attain a proper level for handling. The present work aims to establish a methodology that makes possible the dating by FTM using a mass spectrometer instead of a nuclear reactor. This methodology was applied to apatite samples from Durango, Mexico.

  16. The SAGES Legacy Unifying Globulars and Galaxies survey (SLUGGS): sample definition, methods, and initial results

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, Jean P.; Romanowsky, Aaron J.; Jennings, Zachary G.; Pota, Vincenzo; Kader, Justin; Roediger, Joel C.; Villaume, Alexa; Arnold, Jacob A.; Woodley, Kristin A. [University of California Observatories, 1156 High Street, Santa Cruz, CA 95064 (United States); Strader, Jay [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Forbes, Duncan A.; Pastorello, Nicola; Usher, Christopher; Blom, Christina; Kartha, Sreeja S. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Foster, Caroline; Spitler, Lee R., E-mail: jbrodie@ucsc.edu [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia)

    2014-11-20

    We introduce and provide the scientific motivation for a wide-field photometric and spectroscopic chemodynamical survey of nearby early-type galaxies (ETGs) and their globular cluster (GC) systems. The SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey is being carried out primarily with Subaru/Suprime-Cam and Keck/DEIMOS. The former provides deep gri imaging over a 900 arcmin{sup 2} field-of-view to characterize GC and host galaxy colors and spatial distributions, and to identify spectroscopic targets. The NIR Ca II triplet provides GC line-of-sight velocities and metallicities out to typically ∼8 R {sub e}, and to ∼15 R {sub e} in some cases. New techniques to extract integrated stellar kinematics and metallicities to large radii (∼2-3 R {sub e}) are used in concert with GC data to create two-dimensional (2D) velocity and metallicity maps for comparison with simulations of galaxy formation. The advantages of SLUGGS compared with other, complementary, 2D-chemodynamical surveys are its superior velocity resolution, radial extent, and multiple halo tracers. We describe the sample of 25 nearby ETGs, the selection criteria for galaxies and GCs, the observing strategies, the data reduction techniques, and modeling methods. The survey observations are nearly complete and more than 30 papers have so far been published using SLUGGS data. Here we summarize some initial results, including signatures of two-phase galaxy assembly, evidence for GC metallicity bimodality, and a novel framework for the formation of extended star clusters and ultracompact dwarfs. An integrated overview of current chemodynamical constraints on GC systems points to separate, in situ formation modes at high redshifts for metal-poor and metal-rich GCs.

  17. A framework for inference about carnivore density from unstructured spatial sampling of scat using detector dogs

    Science.gov (United States)

    Thompson, Craig M.; Royle, J. Andrew; Garner, James D.

    2012-01-01

    Wildlife management often hinges upon an accurate assessment of population density. Although undeniably useful, many of the traditional approaches to density estimation such as visual counts, livetrapping, or mark–recapture suffer from a suite of methodological and analytical weaknesses. Rare, secretive, or highly mobile species exacerbate these problems through the reality of small sample sizes and movement on and off study sites. In response to these difficulties, there is growing interest in the use of non-invasive survey techniques, which provide the opportunity to collect larger samples with minimal increases in effort, as well as the application of analytical frameworks that are not reliant on large sample size arguments. One promising survey technique, the use of scat detecting dogs, offers a greatly enhanced probability of detection while at the same time generating new difficulties with respect to non-standard survey routes, variable search intensity, and the lack of a fixed survey point for characterizing non-detection. In order to account for these issues, we modified an existing spatially explicit, capture–recapture model for camera trap data to account for variable search intensity and the lack of fixed, georeferenced trap locations. We applied this modified model to a fisher (Martes pennanti) dataset from the Sierra National Forest, California, and compared the results (12.3 fishers/100 km2) to more traditional density estimates. We then evaluated model performance using simulations at 3 levels of population density. Simulation results indicated that estimates based on the posterior mode were relatively unbiased. We believe that this approach provides a flexible analytical framework for reconciling the inconsistencies between detector dog survey data and density estimation procedures.

  18. Soil Radiological Characterisation Methodology

    International Nuclear Information System (INIS)

    Attiogbe, Julien; Aubonnet, Emilie; De Maquille, Laurence; De Moura, Patrick; Desnoyers, Yvon; Dubot, Didier; Feret, Bruno; Fichet, Pascal; Granier, Guy; Iooss, Bertrand; Nokhamzon, Jean-Guy; Ollivier Dehaye, Catherine; Pillette-Cousin, Lucien; Savary, Alain

    2014-12-01

    This report presents the general methodology and best practice approaches which combine proven existing techniques for sampling and characterisation to assess the contamination of soils prior to remediation. It is based on feedback of projects conducted by main French nuclear stakeholders involved in the field of remediation and dismantling (EDF, CEA, AREVA and IRSN). The application of this methodology will enable the project managers to obtain the elements necessary for the drawing up of files associated with remediation operations, as required by the regulatory authorities. It is applicable to each of the steps necessary for the piloting of remediation work-sites, depending on the objectives targeted (release into the public domain, re-use, etc.). The main part describes the applied statistical methodology with the exploratory analysis and variogram data, identification of singular points and their location. The results obtained permit assessment of a mapping to identify the contaminated surface and subsurface areas. It stakes the way for radiological site characterisation since the initial investigations from historical and functional analysis to check that the remediation objectives have been met. It follows an example application from the feedback of the remediation of a contaminated site on the Fontenay aux Roses facility. It is supplemented by a glossary of main terms used in the field from different publications or international standards. This technical report is a support of the ISO Standard ISO ISO/TC 85/SC 5 N 18557 'Sampling and characterisation principles for soils, buildings and infrastructures contaminated by radionuclides for remediation purposes'. (authors) [fr

  19. 78 FR 47677 - DOE Activities and Methodology for Assessing Compliance With Building Energy Codes

    Science.gov (United States)

    2013-08-06

    ... methodology report, however, for convenience the key points of the methodology are listed below with the... fundamentally different sampling plans and research methodologies? Are there ways to encourage owners and...

  20. Joint analysis of galaxy-galaxy lensing and galaxy clustering: Methodology and forecasts for Dark Energy Survey

    International Nuclear Information System (INIS)

    Park, Y.; Krause, E.; Dodelson, S.; Jain, B.; Amara, A.

    2016-01-01

    Here, the joint analysis of galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth function of large-scale structure. Anticipating a near future application of this analysis to Dark Energy Survey (DES) measurements of galaxy positions and shapes, we develop a practical approach to modeling the assumptions and systematic effects affecting the joint analysis of small-scale galaxy-galaxy lensing and large-scale galaxy clustering. Introducing parameters that characterize the halo occupation distribution (HOD), photometric redshift uncertainties, and shear measurement errors, we study how external priors on different subsets of these parameters affect our growth constraints. Degeneracies within the HOD model, as well as between the HOD and the growth function, are identified as the dominant source of complication, with other systematic effects being subdominant. The impact of HOD parameters and their degeneracies necessitate the detailed joint modeling of the galaxy sample that we employ. We conclude that DES data will provide powerful constraints on the evolution of structure growth in the Universe, conservatively/optimistically constraining the growth function to 7.9%/4.8% with its first-year data that cover over 1000 square degrees, and to 3.9%/2.3% with its full five-year data that will survey 5000 square degrees, including both statistical and systematic uncertainties.

  1. The outlier sample effects on multivariate statistical data processing geochemical stream sediment survey (Moghangegh region, North West of Iran)

    International Nuclear Information System (INIS)

    Ghanbari, Y.; Habibnia, A.; Memar, A.

    2009-01-01

    In geochemical stream sediment surveys in Moghangegh Region in north west of Iran, sheet 1:50,000, 152 samples were collected and after the analyze and processing of data, it revealed that Yb, Sc, Ni, Li, Eu, Cd, Co, as contents in one sample is far higher than other samples. After detecting this sample as an outlier sample, the effect of this sample on multivariate statistical data processing for destructive effects of outlier sample in geochemical exploration was investigated. Pearson and Spear man correlation coefficient methods and cluster analysis were used for multivariate studies and the scatter plot of some elements together the regression profiles are given in case of 152 and 151 samples and the results are compared. After investigation of multivariate statistical data processing results, it was realized that results of existence of outlier samples may appear as the following relations between elements: - true relation between two elements, which have no outlier frequency in the outlier sample. - false relation between two elements which one of them has outlier frequency in the outlier sample. - complete false relation between two elements which both have outlier frequency in the outlier sample

  2. Implied Volatility Surface: Construction Methodologies and Characteristics

    OpenAIRE

    Cristian Homescu

    2011-01-01

    The implied volatility surface (IVS) is a fundamental building block in computational finance. We provide a survey of methodologies for constructing such surfaces. We also discuss various topics which can influence the successful construction of IVS in practice: arbitrage-free conditions in both strike and time, how to perform extrapolation outside the core region, choice of calibrating functional and selection of numerical optimization algorithms, volatility surface dynamics and asymptotics.

  3. Cluster-sample surveys and lot quality assurance sampling to evaluate yellow fever immunisation coverage following a national campaign, Bolivia, 2007.

    Science.gov (United States)

    Pezzoli, Lorenzo; Pineda, Silvia; Halkyer, Percy; Crespo, Gladys; Andrews, Nick; Ronveaux, Olivier

    2009-03-01

    To estimate the yellow fever (YF) vaccine coverage for the endemic and non-endemic areas of Bolivia and to determine whether selected districts had acceptable levels of coverage (>70%). We conducted two surveys of 600 individuals (25 x 12 clusters) to estimate coverage in the endemic and non-endemic areas. We assessed 11 districts using lot quality assurance sampling (LQAS). The lot (district) sample was 35 individuals with six as decision value (alpha error 6% if true coverage 70%; beta error 6% if true coverage 90%). To increase feasibility, we divided the lots into five clusters of seven individuals; to investigate the effect of clustering, we calculated alpha and beta by conducting simulations where each cluster's true coverage was sampled from a normal distribution with a mean of 70% or 90% and standard deviations of 5% or 10%. Estimated coverage was 84.3% (95% CI: 78.9-89.7) in endemic areas, 86.8% (82.5-91.0) in non-endemic and 86.0% (82.8-89.1) nationally. LQAS showed that four lots had unacceptable coverage levels. In six lots, results were inconsistent with the estimated administrative coverage. The simulations suggested that the effect of clustering the lots is unlikely to have significantly increased the risk of making incorrect accept/reject decisions. Estimated YF coverage was high. Discrepancies between administrative coverage and LQAS results may be due to incorrect population data. Even allowing for clustering in LQAS, the statistical errors would remain low. Catch-up campaigns are recommended in districts with unacceptable coverage.

  4. A bench-scale biotreatability methodology to evaluate field bioremediation

    International Nuclear Information System (INIS)

    Saberiyan, A.G.; MacPherson, J.R. Jr.; Moore, R.; Pruess, A.J.; Andrilenas, J.S.

    1995-01-01

    A bench-scale biotreatability methodology was designed to assess field bioremediation of petroleum contaminated soil samples. This methodology was performed successfully on soil samples from more than 40 sites. The methodology is composed of two phases, characterization and experimentation. The first phase is physical, chemical, and biological characterization of the contaminated soil sample. This phase determines soil parameters, contaminant type, presence of indigenous contaminant-degrading bacteria, and bacterial population size. The second phase, experimentation, consists of a respirometry test to measure the growth of microbes indirectly (via generation of CO 2 ) and the consumption of their food source directly (via contaminant loss). Based on a Monod kinetic analysis, the half-life of a contaminant can be calculated. Abiotic losses are accounted for based on a control test. The contaminant molecular structure is used to generate a stoichiometric equation. The stoichiometric equation yields a theoretical ratio for mg of contaminant degraded per mg of CO 2 produced. Data collected from the respirometry test are compared to theoretical values to evaluate bioremediation feasibility

  5. A synthesis of convenience survey and other data to estimate undiagnosed HIV infection among men who have sex with men in England and Wales.

    Science.gov (United States)

    Walker, Kate; Seaman, Shaun R; De Angelis, Daniela; Presanis, Anne M; Dodds, Julie P; Johnson, Anne M; Mercey, Danielle; Gill, O Noel; Copas, Andrew J

    2011-10-01

    Hard-to-reach population subgroups are typically investigated using convenience sampling, which may give biased estimates. Combining information from such surveys, a probability survey and clinic surveillance, can potentially minimize the bias. We developed a methodology to estimate the prevalence of undiagnosed HIV infection among men who have sex with men (MSM) in England and Wales aged 16-44 years in 2003, making fuller use of the available data than earlier work. We performed a synthesis of three data sources: genitourinary medicine clinic surveillance (11 380 tests), a venue-based convenience survey including anonymous HIV testing (3702 MSM) and a general population sexual behaviour survey (134 MSM). A logistic regression model to predict undiagnosed infection was fitted to the convenience survey data and then applied to the MSMs in the population survey to estimate the prevalence of undiagnosed infection in the general MSM population. This estimate was corrected for selection biases in the convenience survey using clinic surveillance data. A sensitivity analysis addressed uncertainty in our assumptions. The estimated prevalence of undiagnosed HIV in MSM was 2.4% [95% confidence interval (95% CI 1.7-3.0%)], and between 1.6% (95% CI 1.1-2.0%) and 3.3% (95% CI 2.4-4.1%) depending on assumptions; corresponding to 5500 (3390-7180), 3610 (2180-4740) and 7570 (4790-9840) men, and undiagnosed fractions of 33, 24 and 40%, respectively. Our estimates are consistent with earlier work that did not make full use of data sources. Reconciling data from multiple sources, including probability-, clinic- and venue-based convenience samples can reduce bias in estimates. This methodology could be applied in other settings to take full advantage of multiple imperfect data sources.

  6. Comparative analysis as a basic research orientation: Key methodological problems

    Directory of Open Access Journals (Sweden)

    N P Narbut

    2015-12-01

    Full Text Available To date, the Sociological Laboratory of the Peoples’ Friendship University of Russia has accumulated a vast experience in the field of cross-cultural studies reflected in the publications based on the results of mass surveys conducted in Moscow, Maikop, Beijing, Guangzhou, Prague, Belgrade, and Pristina. However, these publications mainly focus on the comparisons of the empirical data rather than methodological and technical issues, that is why the aim of this article is to identify key problems of the comparative analysis in cross-cultural studies that become evident only if you conduct an empirical research yourself - from the first step of setting the problem and approving it by all the sides (countries involved to the last step of interpreting and comparing the data obtained. The authors are sure that no sociologist would ever doubt the necessity and importance of comparative analysis in the broadest sense of the word, but at the same time very few are ready to discuss its key methodological challenges and prefer to ignore them completely. We summarize problems of the comparative analysis in sociology as follows: (1 applying research techniques to the sample in another country - both in translating and adapting them to different social realities and worldview (in particular, the problematic status of standardization and qualitative approach; (2 choosing “right” respondents to question and relevant cases (cultures to study; (3 designing the research scheme, i.e. justifying the sequence of steps (what should go first - methodology or techniques; (4 accepting the procedures that are correct within one country for cross-cultural work (whether or not that is an appropriate choice.

  7. Microphysics evolution and methodology

    International Nuclear Information System (INIS)

    Dionisio, J.S.

    1990-01-01

    A few general features of microscopics evolution and their relationship with microscopics methodology are briefly surveyed. Several pluri-disciplinary and interdisciplinary aspects of microscopics research are also discussed in the present scientific context. The need for an equilibrium between individual tendencies and collective constraints required by team work, already formulated thirty years ago by Frederic Joliot, is particularly stressed in the present conjuncture of Nuclear Research favouring very large team projects and discouraging individual initiatives. The increasing importance of the science of science (due to their multiple social, economical, ecological aspects) and the stronger competition between national and international tendencies of scientific (and technical) cooperation are also discussed. (author)

  8. Explaining health care expenditure variation: large-sample evidence using linked survey and health administrative data.

    Science.gov (United States)

    Ellis, Randall P; Fiebig, Denzil G; Johar, Meliyanni; Jones, Glenn; Savage, Elizabeth

    2013-09-01

    Explaining individual, regional, and provider variation in health care spending is of enormous value to policymakers but is often hampered by the lack of individual level detail in universal public health systems because budgeted spending is often not attributable to specific individuals. Even rarer is self-reported survey information that helps explain this variation in large samples. In this paper, we link a cross-sectional survey of 267 188 Australians age 45 and over to a panel dataset of annual healthcare costs calculated from several years of hospital, medical and pharmaceutical records. We use this data to distinguish between cost variations due to health shocks and those that are intrinsic (fixed) to an individual over three years. We find that high fixed expenditures are positively associated with age, especially older males, poor health, obesity, smoking, cancer, stroke and heart conditions. Being foreign born, speaking a foreign language at home and low income are more strongly associated with higher time-varying expenditures, suggesting greater exposure to adverse health shocks. Copyright © 2013 John Wiley & Sons, Ltd.

  9. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Zane Hills, Hughes and Shungnak quadrangles, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential.The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska.For this report, DGGS funded reanalysis of 105 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Zane Hills area in the Hughes and Shungnak quadrangles, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical databases of both agencies.

  10. A methodology for digital soil mapping in poorly-accessible areas

    NARCIS (Netherlands)

    Cambule, A.; Rossiter, D.G.; Stoorvogel, J.J.

    2013-01-01

    Effective soil management requires knowledge of the spatial patterns of soil variation within the landscape to enable wise land use decisions. This is typically obtained through time-consuming and costly surveys. The aim of this study was to develop a cost-efficient methodology for digital soil

  11. The environmental survey manual

    International Nuclear Information System (INIS)

    1987-08-01

    The purpose of this manual is to provide guidance to the Survey and Sampling and Analysis teams that conduct the one-time Environmental Survey of the major US Department of Energy (DOE) operating facilities. This manual includes a discussion of DOE's policy on environmental issues, a review of statutory guidance as it applies to the Survey, the procedures and protocols to be used by the Survey teams, criteria for the use of the Survey teams in evaluating existing environmental data for the Survey effort, generic technical checklists used in every Survey, health and safety guidelines for the personnel conducting the Survey, including the identification of potential hazards, prescribed protective equipment, and emergency procedures, the required formats for the Survey reports, guidance on identifying environmental problems that need immediate attention by the Operations Office responsible for the particular facility, and procedures and protocols for the conduct of sampling and analysis

  12. Guide to the design and application of online questionnaire surveys.

    Science.gov (United States)

    Regmi, Pramod R; Waithaka, Elizabeth; Paudyal, Anjana; Simkhada, Padam; van Teijlingen, Edwin

    2016-12-01

    Collecting research data through traditional approaches (face-to-face, postal or telephone survey) can be costly and time consuming. The emerging data collection approach based on internet/e-based technologies (e.g. online platforms and email), is a relatively cost effective survey alternative. These novel data collection strategies can collect large amounts of data from participants in a short time frame. Similarly, they also seem to be feasible and effective in collecting data on sensitive issues or with samples they are generally hard to reach, for example, men who have sex with men (MSM) or migrants. As a significant proportion of the population currently in the world are digitally connected, the shift from postal (paper-pencil) or telephone towards online survey use in research is in the interests of researchers in academia as well as in the commercial world. However, compared to designing and executing paper version of the questionnaire, there is limited literature to help a starting researcher with the design and a use of online questionnaires. This short paper highlights issues around: a) methodological aspect of online questionnaire survey; b) online survey planning and management; and c) ethical concerns that may arise while using this option. We believe that this paper will be useful for researchers who want to gain knowledge or apply this approach in their research.

  13. Methodological exploratory study applied to occupational epidemiology

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Janete C.G. Gaburo; Vasques, MOnica Heloisa B.; Fontinele, Ricardo S.; Sordi, Gian Maria A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: janetegc@ipen.br

    2007-07-01

    The utilization of epidemiologic methods and techniques has been object of practical experimentation and theoretical-methodological reflection in health planning and programming process. Occupational Epidemiology is the study of the causes and prevention of diseases and injuries from exposition and risks in the work environment. In this context, there is no intention to deplete such a complex theme but to deal with basic concepts of Occupational Epidemiology, presenting the main characteristics of the analysis methods used in epidemiology, as investigate the possible determinants of exposition (chemical, physical and biological agents). For this study, the social-demographic profile of the IPEN-CNEN/SP work force was used. The knowledge of this reference population composition is based on sex, age, educational level, marital status and different occupations, aiming to know the relation between the health aggravating factors and these variables. The methodology used refers to a non-experimental research based on a theoretical methodological practice. The work performed has an exploratory character, aiming a later survey of indicators in the health area in order to analyze possible correlations related to epidemiologic issues. (author)

  14. Methodological exploratory study applied to occupational epidemiology

    International Nuclear Information System (INIS)

    Carneiro, Janete C.G. Gaburo; Vasques, MOnica Heloisa B.; Fontinele, Ricardo S.; Sordi, Gian Maria A.

    2007-01-01

    The utilization of epidemiologic methods and techniques has been object of practical experimentation and theoretical-methodological reflection in health planning and programming process. Occupational Epidemiology is the study of the causes and prevention of diseases and injuries from exposition and risks in the work environment. In this context, there is no intention to deplete such a complex theme but to deal with basic concepts of Occupational Epidemiology, presenting the main characteristics of the analysis methods used in epidemiology, as investigate the possible determinants of exposition (chemical, physical and biological agents). For this study, the social-demographic profile of the IPEN-CNEN/SP work force was used. The knowledge of this reference population composition is based on sex, age, educational level, marital status and different occupations, aiming to know the relation between the health aggravating factors and these variables. The methodology used refers to a non-experimental research based on a theoretical methodological practice. The work performed has an exploratory character, aiming a later survey of indicators in the health area in order to analyze possible correlations related to epidemiologic issues. (author)

  15. Measuring our Universe from Galaxy Redshift Surveys.

    Science.gov (United States)

    Lahav, Ofer; Suto, Yasushi

    2004-01-01

    Galaxy redshift surveys have achieved significant progress over the last couple of decades. Those surveys tell us in the most straightforward way what our local Universe looks like. While the galaxy distribution traces the bright side of the Universe, detailed quantitative analyses of the data have even revealed the dark side of the Universe dominated by non-baryonic dark matter as well as more mysterious dark energy (or Einstein's cosmological constant). We describe several methodologies of using galaxy redshift surveys as cosmological probes, and then summarize the recent results from the existing surveys. Finally we present our views on the future of redshift surveys in the era of precision cosmology.

  16. A study on assessment methodology of surveillance test interval and Allowed Outage Time

    Energy Technology Data Exchange (ETDEWEB)

    Che, Moo Seong; Cheong, Chang Hyeon; Ryu, Yeong Woo; Cho, Jae Seon; Heo, Chang Wook; Kim, Do Hyeong; Kim, Joo Yeol; Kim, Yun Ik; Yang, Hei Chang [Seoul National Univ., Seoul (Korea, Republic of)

    1997-07-15

    Objectives of this study is the development of methodology by which assesses the optimization of Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korean nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches are performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method. In the second year of this study, the sensitivity analyses about the failure factors of the components are performed in the bases of the assessment methodologies of the first study, the interaction modeling of the STI and AOT is quantified. And the reliability assessment methodology about the diesel generator is reviewed and applied to the PSA code.

  17. A study on assessment methodology of surveillance test interval and Allowed Outage Time

    International Nuclear Information System (INIS)

    Che, Moo Seong; Cheong, Chang Hyeon; Ryu, Yeong Woo; Cho, Jae Seon; Heo, Chang Wook; Kim, Do Hyeong; Kim, Joo Yeol; Kim, Yun Ik; Yang, Hei Chang

    1997-07-01

    Objectives of this study is the development of methodology by which assesses the optimization of Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korean nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches are performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method. In the second year of this study, the sensitivity analyses about the failure factors of the components are performed in the bases of the assessment methodologies of the first study, the interaction modeling of the STI and AOT is quantified. And the reliability assessment methodology about the diesel generator is reviewed and applied to the PSA code

  18. Diseño y metodología de la Encuesta Nacional de Salud 2000 National Health Survey 2000: design and methodology

    Directory of Open Access Journals (Sweden)

    Jaime Sepúlveda

    2007-01-01

    Full Text Available OBJETIVO: Como parte del Sistema de Encuestas Nacionales de Salud, durante los últimos meses de 1999 y los primeros tres del año 2000 se realizó la Encuesta Nacional de Salud de México (ENSA 2000. Se estudió la accesibilidad, calidad, utilización y cobertura de los Servicios de Salud; de modo adicional se actualizaron los marcadores serológicos de enfermedades infecciosas prevenibles por vacunación, infecciones de transmisión sexual y hepatitis. MATERIAL Y MÉTODOS: Para la ENSA 2000 se seleccionaron tres grupos etarios y a los utilizadores de los servicios de salud. Se captó la información mediante entrevista directa y se tomaron muestras biológicas para análisis clínicos y medidas de parámetros biológicos y somatométricos. El diseño muestral de la ENSA 2000 fue probabilístico, polietápico, estratificado y de conglomerados. El tamaño de la muestra fue de 1 470 viviendas por estado, para un total de 47 040 viviendas a nivel nacional; los factores de expansión se modificaron por la falta de respuesta y la posestratificación. El personal operativo se capacitó y estandarizó para mantener una alta respuesta, en especial para las muestras de sangre. RESULTADOS: En total se obtuvieron 83 157 muestras de sangre de las 94 000 esperadas (respuesta de 88% que se mantuvieron refrigeradas en tanto se ubicaron en el laboratorio del Instituto Nacional de Salud Pública donde se prepararon cuatro alícuotas y se congelaron a -150° C hasta el análisis.OBJECTIVE: The 2000 Mexican National Health Survey (NHS was created as part of the System for National Health Surveys conducted during the last months of 1999 and the first three of 2000. The 2000 NHS is a probabilistic survey of households from which users of health services were selected according to three age groups. Information was gathered through direct interviews with appropriate informants. Biological samples were taken for clinical tests as well as for measuring biological and

  19. Results and evaluation of a survey to estimate Pacific walrus population size, 2006

    Science.gov (United States)

    Speckman, Suzann G.; Chernook, Vladimir I.; Burn, Douglas M.; Udevitz, Mark S.; Kochnev, Anatoly A.; Vasilev, Alexander; Jay, Chadwick V.; Lisovsky, Alexander; Fischbach, Anthony S.; Benter, R. Bradley

    2011-01-01

    In spring 2006, we conducted a collaborative U.S.-Russia survey to estimate abundance of the Pacific walrus (Odobenus rosmarus divergens). The Bering Sea was partitioned into survey blocks, and a systematic random sample of transects within a subset of the blocks was surveyed with airborne thermal scanners using standard strip-transect methodology. Counts of walruses in photographed groups were used to model the relation between thermal signatures and the number of walruses in groups, which was used to estimate the number of walruses in groups that were detected by the scanner but not photographed. We also modeled the probability of thermally detecting various-sized walrus groups to estimate the number of walruses in groups undetected by the scanner. We used data from radio-tagged walruses to adjust on-ice estimates to account for walruses in the water during the survey. The estimated area of available habitat averaged 668,000 km2 and the area of surveyed blocks was 318,204 km2. The number of Pacific walruses within the surveyed area was estimated at 129,000 with 95% confidence limits of 55,000 to 507,000 individuals. This value can be used by managers as a minimum estimate of the total population size.

  20. Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease: Methodology and Baseline Sample Characteristics.

    Science.gov (United States)

    Byun, Min Soo; Yi, Dahyun; Lee, Jun Ho; Choe, Young Min; Sohn, Bo Kyung; Lee, Jun-Young; Choi, Hyo Jung; Baek, Hyewon; Kim, Yu Kyeong; Lee, Yun-Sang; Sohn, Chul-Ho; Mook-Jung, Inhee; Choi, Murim; Lee, Yu Jin; Lee, Dong Woo; Ryu, Seung-Ho; Kim, Shin Gyeom; Kim, Jee Wook; Woo, Jong Inn; Lee, Dong Young

    2017-11-01

    The Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (KBASE) aimed to recruit 650 individuals, aged from 20 to 90 years, to search for new biomarkers of Alzheimer's disease (AD) and to investigate how multi-faceted lifetime experiences and bodily changes contribute to the brain changes or brain pathologies related to the AD process. All participants received comprehensive clinical and neuropsychological evaluations, multi-modal brain imaging, including magnetic resonance imaging, magnetic resonance angiography, [ 11 C]Pittsburgh compound B-positron emission tomography (PET), and [ 18 F]fluorodeoxyglucose-PET, blood and genetic marker analyses at baseline, and a subset of participants underwent actigraph monitoring and completed a sleep diary. Participants are to be followed annually with clinical and neuropsychological assessments, and biannually with the full KBASE assessment, including neuroimaging and laboratory tests. As of March 2017, in total, 758 individuals had volunteered for this study. Among them, in total, 591 participants-291 cognitively normal (CN) old-aged individuals, 74 CN young- and middle-aged individuals, 139 individuals with mild cognitive impairment (MCI), and 87 individuals with AD dementia (ADD)-were enrolled at baseline, after excluding 162 individuals. A subset of participants (n=275) underwent actigraph monitoring. The KBASE cohort is a prospective, longitudinal cohort study that recruited participants with a wide age range and a wide distribution of cognitive status (CN, MCI, and ADD) and it has several strengths in its design and methodologies. Details of the recruitment, study methodology, and baseline sample characteristics are described in this paper.