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Sample records for case control studies

  1. Case-control studies in neurosurgery.

    Science.gov (United States)

    Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

    2014-08-01

    Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

  2. Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.

    Science.gov (United States)

    Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

    2017-06-05

    Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. Published by Elsevier Ltd.

  3. Methodology Series Module 2: Case-control Studies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

  4. Case-control studies in diabetes. Do they really use a case-control design?

    Science.gov (United States)

    Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

    2017-07-01

    Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

  5. Accounting for control mislabeling in case-control biomarker studies.

    Science.gov (United States)

    Rantalainen, Mattias; Holmes, Chris C

    2011-12-02

    In biomarker discovery studies, uncertainty associated with case and control labels is often overlooked. By omitting to take into account label uncertainty, model parameters and the predictive risk can become biased, sometimes severely. The most common situation is when the control set contains an unknown number of undiagnosed, or future, cases. This has a marked impact in situations where the model needs to be well-calibrated, e.g., when the prediction performance of a biomarker panel is evaluated. Failing to account for class label uncertainty may lead to underestimation of classification performance and bias in parameter estimates. This can further impact on meta-analysis for combining evidence from multiple studies. Using a simulation study, we outline how conventional statistical models can be modified to address class label uncertainty leading to well-calibrated prediction performance estimates and reduced bias in meta-analysis. We focus on the problem of mislabeled control subjects in case-control studies, i.e., when some of the control subjects are undiagnosed cases, although the procedures we report are generic. The uncertainty in control status is a particular situation common in biomarker discovery studies in the context of genomic and molecular epidemiology, where control subjects are commonly sampled from the general population with an established expected disease incidence rate.

  6. Hospital visitors as controls in case-control studies

    Directory of Open Access Journals (Sweden)

    Gulnar Azevedo S Mendonça

    2001-10-01

    Full Text Available OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute in Rio de Janeiro (Brazil. METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk, but not statistically significant. Family history of breast cancer was a risk factor in Models 2 and 3, but no association was found in Model 1. In multivariate analysis a significant risk of breast cancer was found when there was a family history of breast cancer in Models 2 and 3 but not in Model 1. CONCLUSIONS: These results indicate that while investigating risk factors unrelated to family history of cancer, the use of hospital visitors as controls may be a valid and feasible alternative.

  7. Case Studies in Modelling, Control in Food Processes.

    Science.gov (United States)

    Glassey, J; Barone, A; Montague, G A; Sabou, V

    This chapter discusses the importance of modelling and control in increasing food process efficiency and ensuring product quality. Various approaches to both modelling and control in food processing are set in the context of the specific challenges in this industrial sector and latest developments in each area are discussed. Three industrial case studies are used to demonstrate the benefits of advanced measurement, modelling and control in food processes. The first case study illustrates the use of knowledge elicitation from expert operators in the process for the manufacture of potato chips (French fries) and the consequent improvements in process control to increase the consistency of the resulting product. The second case study highlights the economic benefits of tighter control of an important process parameter, moisture content, in potato crisp (chips) manufacture. The final case study describes the use of NIR spectroscopy in ensuring effective mixing of dry multicomponent mixtures and pastes. Practical implementation tips and infrastructure requirements are also discussed.

  8. Case-Control Studies - An Efficient Observational Study Design

    NARCIS (Netherlands)

    van Stralen, Karlijn J.; Dekker, Friedo W.; Zoccali, Carmine; Jager, Kitty J.

    2010-01-01

    Case-control studies are an efficient research method for investigating risk factors of a disease. The method involves the comparison of the odds of exposure in a patient group with that of the odds of exposure in a control group. As only a minority of the population is included in the study, less

  9. Pilot case-control study of paediatric falls from windows.

    Science.gov (United States)

    Johnston, Brian D; Quistberg, D Alexander; Shandro, Jamie R; Partridge, Rebecca L; Song, Hyun Rae; Ebel, Beth E

    2011-12-01

    Unintentional falls from windows are an important cause of paediatric morbidity. There have been no controlled studies to identify modifiable environmental risk factors for window falls in young children. The authors have piloted a case-control study to test procedures for case identification, subject enrolment, and environmental data collection. Case windows were identified when a child 0-9 years old presented for care after a fall from that window. Control windows were identified (1) from the child's home and (2) from the home of an age- and gender-matched child seeking care for an injury diagnosis not related to a window fall. Study staff visited enrolled homes to collect window measurements and conduct window screen performance tests. The authors enrolled and collected data on 18 case windows, 18 in-home controls, and 14 matched community controls. Six potential community controls were contacted for every one enrolled. Families who completed the home visit viewed study procedures positively. Case windows were more likely than community controls to be horizontal sliders (100% vs 50%), to have deeper sills (6.28 vs 4.31 inches), to be higher above the exterior surface (183 vs 82 inches), and to have screens that failed below a threshold derived from the static pressure of a 3-year-old leaning against the mesh (60.0% vs 16.7%). Case windows varied very little from in-home controls. Case-control methodology can be used to study risk factors for paediatric falls from windows. Recruitment of community controls is challenging but essential, because in-home controls tend to be over-matched on important variables. A home visit allows direct measurement of window type, height, sill depth, and screen performance. These variables should all be investigated in subsequent, larger studies covering major housing markets.

  10. Homocyst(e)ine and cardiovascular disease: a systematic review of the evidence with special emphasis on case-control studies and nested case-control studies.

    Science.gov (United States)

    Ford, Earl S; Smith, S Jay; Stroup, Donna F; Steinberg, Karen K; Mueller, Patricia W; Thacker, Stephen B

    2002-02-01

    Elevated concentrations of homocyst(e)ine are thought to increase the risk of vascular diseases including coronary heart disease and cerebrovascular disease. We searched MEDLINE (1966-1999), EMBASE (1974-1999), SciSearch (1974- 1999), and Dissertation Abstracts (1999) for articles and theses about homocyst(e)ine concentration and coronary heart disease and cerebrovascular disease. We included 57 publications (3 cohort studies, 12 nested case-control studies, 42 case-control studies) that reported results on 5518 people with coronary heart disease (11,068 control subjects) and 1817 people with cerebrovascular disease (4787 control subjects) in our analysis. For coronary heart disease, the summary odds ratios (OR) for a 5-micromol/l increase in homocyst(e)ine concentration were 1.06 (95% CI : 0.99-1.13) for 2 publications of cohort studies, 1.23 (95% CI : 1.07-1.41) for 10 publications of nested case-control studies, and 1.70 (95% CI : 1.50-1.93) for 26 publications of case-control studies. For cerebrovascular disease, the summary OR for a 5-micromol/l increase in homocyst(e)ine concentration were 1.10 (95% CI : 0.94-1.28) for 2 publications of cohort studies, 1.58 (95% CI : 1.35-1.85) for 5 publications of nested case-control studies, and 2.16 (95% CI : 1.65-2.82) for 17 publications of case-control studies. Prospective studies offer weaker support than case-control studies for an association between homocyst(e)ine concentration and cardiovascular disease. Although other lines of evidence support a role for homocyst(e)ine in the pathogenesis of cardiovascular disease, more information from prospective epidemiological studies or clinical trials is needed to clarify this role.

  11. Matched case-control studies: a review of reported statistical methodology

    Directory of Open Access Journals (Sweden)

    Niven DJ

    2012-04-01

    Full Text Available Daniel J Niven1, Luc R Berthiaume2, Gordon H Fick1, Kevin B Laupland11Department of Critical Care Medicine, Peter Lougheed Centre, Calgary, 2Department of Community Health Sciences, University of Calgary, Calgary, Alberta, CanadaBackground: Case-control studies are a common and efficient means of studying rare diseases or illnesses with long latency periods. Matching of cases and controls is frequently employed to control the effects of known potential confounding variables. The analysis of matched data requires specific statistical methods.Methods: The objective of this study was to determine the proportion of published, peer reviewed matched case-control studies that used statistical methods appropriate for matched data. Using a comprehensive set of search criteria we identified 37 matched case-control studies for detailed analysis.Results: Among these 37 articles, only 16 studies were analyzed with proper statistical techniques (43%. Studies that were properly analyzed were more likely to have included case patients with cancer and cardiovascular disease compared to those that did not use proper statistics (10/16 or 63%, versus 5/21 or 24%, P = 0.02. They were also more likely to have matched multiple controls for each case (14/16 or 88%, versus 13/21 or 62%, P = 0.08. In addition, studies with properly analyzed data were more likely to have been published in a journal with an impact factor listed in the top 100 according to the Journal Citation Reports index (12/16 or 69%, versus 1/21 or 5%, P ≤ 0.0001.Conclusion: The findings of this study raise concern that the majority of matched case-control studies report results that are derived from improper statistical analyses. This may lead to errors in estimating the relationship between a disease and exposure, as well as the incorrect adaptation of emerging medical literature.Keywords: case-control, matched, dependent data, statistics

  12. Population versus hospital controls for case-control studies on cancers in Chinese hospitals.

    Science.gov (United States)

    Li, Lin; Zhang, Min; Holman, D'Arcy

    2011-12-15

    Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

  13. Population versus hospital controls for case-control studies on cancers in Chinese hospitals

    Directory of Open Access Journals (Sweden)

    Li Lin

    2011-12-01

    Full Text Available Abstract Background Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. Methods We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs and 95% confidence intervals (CIs were obtained using conditional logistic regression analyses. Results The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93. For exposure of green tea drinking, the adjusted ORs (95% CIs comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83 and 0.21 (0.27, 0.74 for three cancers combined, 0.06 (0.01, 0.61 and 0.07 (0.01, 0.47 for breast cancer, 0.52 (0.29, 0.94 and 0.45 (0.25, 0.82 for colorectal cancer, 0.65 (0.08, 5.63 and 0.57 (0.07, 4.79 for leukemia using hospital and population controls respectively. Conclusions The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

  14. Assessment of global phase uncertainty in case-control studies

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    van Houwelingen Hans C

    2009-09-01

    Full Text Available Abstract Background In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The measure 1 quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: and based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. Results A new global relative efficiency measure was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Conclusion Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk.

  15. Association Between Anemia and Cerebral Venous Thrombosis: Case-Control Study

    NARCIS (Netherlands)

    Coutinho, Jonathan M.; Zuurbier, Susanna M.; Gaartman, Aafke E.; Dikstaal, Arienne A.; Stam, Jan; Middeldorp, Saskia; Cannegieter, Suzanne C.

    2015-01-01

    Anemia is often considered to be a risk factor for cerebral venous thrombosis (CVT), but this assumption is mostly based on case reports. We investigated the association between anemia and CVT in a controlled study. Unmatched case-control study: cases were adult patients with CVT included in a

  16. Case-control vaccine effectiveness studies: Data collection, analysis and reporting results.

    Science.gov (United States)

    Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

    2017-06-05

    The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection

  17. Case-control study on uveal melanoma (RIFA: rational and design

    Directory of Open Access Journals (Sweden)

    Schmidt-Pokrzywniak Andrea

    2004-08-01

    Full Text Available Abstract Background Although a rare disease, uveal melanoma is the most common primary intraocular malignancy in adults, with an incidence rate of up to 1.0 per 100,000 persons per year in Europe. Only a few consistent risk factors have been identified for this disease. We present the study design of an ongoing incident case-control study on uveal melanoma (acronym: RIFA study that focuses on radiofrequency radiation as transmitted by radio sets and wireless telephones, occupational risk factors, phenotypical characteristics, and UV radiation. Methods/Design We conduct a case-control study to identify the role of different exposures in the development of uveal melanoma. The cases of uveal melanoma were identified at the Division of Ophthalmology, University of Essen, a referral centre for tumours of the eye. We recruit three control groups: population controls, controls sampled from those ophthalmologists who referred cases to the Division of Ophthalmology, University of Duisburg-Essen, and sibling controls. For each case the controls are matched on sex and age (five year groups, except for sibling controls. The data are collected from the study participants by short self-administered questionnaire and by telephone interview. During and at the end of the field phase, the data are quality-checked. To estimate the effect of exposures on uveal melanoma risk, we will use conditional logistic regression that accounts for the matching factors and allows to control for potential confounding.

  18. Struggling doctors in specialist training: a case control study

    DEFF Research Database (Denmark)

    O'Neill, Lotte; Norberg, Karen; Thomsen, Maria

    ), or transferred (i.e. had unplanned changes in place of training/ward due to failure to thrive or due to inadequate development of competences), or dropped out (i.e. were dismissed from, had resigned from, or changed their speciality). Controls were a random sample of doctors in the source population, who were......Abstract summary The aim of this cummulative incidence case-control study was to examine: if struggling trainees in medical specialist training (cases) tended to struggle already in medical school or not compared to non-struggling controls, and which performance indicators during medical school...... seemed to predict struggling in postgraduate education if any. The study design is rooted in epidemiological methodology. Struggling doctors in specialist training: a case-control study. It has been reported in the international literature, that around 3-10% of doctors in post-garduate specialist...

  19. Patterned genital injury in cases of rape - A case-control study

    DEFF Research Database (Denmark)

    Astrup, Birgitte Schmidt; Ravn, Pernille; Thomsen, Jørgen Lange

    2013-01-01

    A pattern of genital injury that separates trauma seen in sexual assault cases from trauma seen following consensual sexual intercourse has been a matter of debate. This study aimed at clarifying the question by eliminating as many confounders as possible in a prospective, case-control setup. A t...

  20. The Misconception of Case-Control Studies in the Plastic Surgery Literature: A Literature Audit.

    Science.gov (United States)

    Hatchell, Alexandra C; Farrokhyar, Forough; Choi, Matthew

    2017-06-01

    Case-control study designs are commonly used. However, many published case-control studies are not true case-controls and are in fact mislabeled. The purpose of this study was to identify all case-control studies published in the top three plastic surgery journals over the past 10 years, assess which were truly case-control studies, clarify the actual design of the articles, and address common misconceptions. MEDLINE, Embase, and Web of Science databases were searched for case-control studies in the three highest-impact factor plastic surgery journals (2005 to 2015). Two independent reviewers screened the resulting titles, abstracts, and methods, if applicable, to identify articles labeled as case-control studies. These articles were appraised and classified as true case-control studies or non-case-control studies. The authors found 28 articles labeled as case-control studies. However, only six of these articles (21 percent) were truly case-control designs. Of the 22 incorrectly labeled studies, one (5 percent) was a randomized controlled trial, three (14 percent) were nonrandomized trials, two (9 percent) were prospective comparative cohort designs, 14 (64 percent) were retrospective comparative cohort designs, and two (9 percent) were cross-sectional designs. The mislabeling was worse in recent years, despite increases in evidence-based medicine awareness. The majority of published case-control studies are not in fact case-control studies. This misunderstanding is worsening with time. Most of these studies are actually comparative cohort designs. However, some studies are truly clinical trials and thus a higher level of evidence than originally proposed.

  1. A case-control study assessing depression in patients with periodontitis

    Directory of Open Access Journals (Sweden)

    Shiyamali Sundararajan

    2017-01-01

    Full Text Available Background: Chronic periodontitis is an inflammatory disease of the supporting structures of the tooth. One of the important non-oral risk factors for periodontitis is psychosocial stress and depression. Depression affects oral health by affecting the immune system through its effects on hypothalamic pituitary axis system. Periodontal inflammatory surface area (PISA is a system used to assess inflammatory burden in the periodontal tissue. Aim: The aim of this study is to assess the relationship between PISA and depression. Settings and Design: The design of the study is case-control study. Materials and Methods: The study design is a case-control study with forty patients each in case and control groups. The periodontal inflammatory level was assessed by PISA system and the levels of depression was assessed by using Beck's Depression Inventory (BDI. Statistical Analysis: Student's t-test was used to compare PISA and BDI scores. The BDI score (mean ± standard deviation [SD] for controls was 12.75 ± 6.82 compared to 22.73 ± 4.40 for the cases. The comparison (t = 7.78 was statistically significant at P < 0.0001. The PISA score (mean ± SD for controls was 210.47 ± 76.80 compared to the PISA score of 1069.50 ± 204.21 for cases which was statistically significant (t = 24.90; P < 0.0001. Results: Significantly higher BDI scores were observed in patients with chronic periodontitis than healthy controls. Conclusion: This study clearly reveals a significant association between the severity of depression and inflammatory burden.

  2. Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

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    Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

    2014-08-15

    Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. 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.

  3. The Glioma International Case-Control Study

    DEFF Research Database (Denmark)

    Amirian, E. Susan; Armstrong, Georgina N; Zhou, Renke

    2016-01-01

    Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly...... describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen...

  4. Colon cancer controls versus population controls in case-control studies of occupational risk factors

    DEFF Research Database (Denmark)

    Kaerlev, Linda; Lynge, Elsebeth; Sabroe, Svend

    2004-01-01

    are interchangeable with the experience for population controls. Patient controls may even be preferable from population controls under certain conditions. In this study we examine if colon cancer patients can serve as surrogates for proper population controls in case-control studies of occupational risk factors...... about occupational, medical and life style conditions. RESULTS: No statistical significant difference for educational level, medical history or smoking status was seen between the two control groups. There was evidence of a higher alcohol intake, less frequent work as a farmer and less exposure...... to pesticides among colon cancer controls. CONCLUSIONS: Use of colon cancer controls may provide valid exposure estimates in studies of many occupational risk factors for cancer, but not for studies on exposure related to farming....

  5. Risk Factors for Anemia in Pregnancy: A Case Control Study

    Directory of Open Access Journals (Sweden)

    Rutuja Pundkar

    2017-12-01

    Full Text Available Background: Aim of the study was to find the risk factors leading to Anemia in pregnancy. The main objective was to study the various sociodemographic factors leading to anemia. And to assess the knowledge about anemia among study participants. Material and methods: The present Case control study was carried out at Primary Health Centre, to determine the risk factors leading to anemia in pregnancy. A total of 308 pregnant females were registered. Among them two groups were made, group I cases and group II controls. Each group had 50 cases each. Laboratory test were done and females having hemoglobin less than 11mg/dl were considered anemic. Anemic females were considered cases and females having Hb >11mg/dl were considered controls. Data analysis was done using SPSS software. Results: The overall mean haemoglobin (Hb was 11.55g/dL in controls, whereas it was seen that among the cases it was 9.58g/dL.It would seem that diet, family size, education, social class, gravida and parity are associated with anemia in pregnancy. Conclusion: After adjusting for all the possible covariates there seems to be significant association between Hb levels and age group, education level, family size, diet, gravida and parity.

  6. Hypothyroidism among SLE patients: Case-control study.

    Science.gov (United States)

    Watad, Abdulla; Mahroum, Naim; Whitby, Aaron; Gertel, Smadar; Comaneshter, Doron; Cohen, Arnon D; Amital, Howard

    2016-05-01

    The prevalence of hypothyroidism in SLE patients varies considerably and early reports were mainly based on small cohorts. To investigate the association between SLE and hypothyroidism. Patients with SLE were compared with age and sex-matched controls regarding the proportion of hypothyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study was performed utilizing the medical database of Clalit Health Services. The study included 5018 patients with SLE and 25,090 age and sex-matched controls. The proportion of hypothyroidism in patients with SLE was increased compared with the prevalence in controls (15.58% and 5.75%, respectively, Phypothyroidism (odds ratio 2.644, 95% confidence interval 2.405-2.908). Patients with SLE have a greater proportion of hypothyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of the possibility of thyroid dysfunction. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Selective serotonin reuptake inhibitors and gastrointestinal bleeding: a case-control study.

    Directory of Open Access Journals (Sweden)

    Alfonso Carvajal

    Full Text Available BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs have been associated with upper gastrointestinal (GI bleeding. Given their worldwide use, even small risks account for a large number of cases. This study has been conducted with carefully collected information to further investigate the relationship between SSRIs and upper GI bleeding. METHODS: We conducted a case-control study in hospitals in Spain and in Italy. Cases were patients aged ≥18 years with a primary diagnosis of acute upper GI bleeding diagnosed by endoscopy; three controls were matched by sex, age, date of admission (within 3 months and hospital among patients who were admitted for elective surgery for non-painful disorders. Exposures to SSRIs, other antidepressants and other drugs were defined as any use of these drugs in the 7 days before the day on which upper gastrointestinal bleeding started (index day. RESULTS: 581 cases of upper GI bleeding and 1358 controls were considered eligible for the study; no differences in age or sex distribution were observed between cases and controls after matching. Overall, 4.0% of the cases and 3.3% of controls used an SSRI antidepressant in the week before the index day. No significant risk of upper GI bleeding was encountered for SSRI antidepressants (adjusted odds ratio, 1.06, 95% CI, 0.57-1.96 or for whichever other grouping of antidepressants. CONCLUSIONS: The results of this case-control study showed no significant increase in upper GI bleeding with SSRIs and provide good evidence that the magnitude of any increase in risk is not greater than 2.

  8. Determinants of podoconiosis, a case control study | Feleke ...

    African Journals Online (AJOL)

    The sample size was calculated using Epi-info soft ware: 95% CI, 85% power, control to case ratio of 2:1, expected frequency of barefoot among controls 50%, odds ratio of 1.5 and non-response rate of 10% yielding 1148 study participants. Binary logistic regression was used to identify the determinants of Podoconiosis.

  9. A case-control study of risk factors for epithelial ovarian cancer

    Directory of Open Access Journals (Sweden)

    Ghaem Maghami Noori F

    2001-09-01

    Full Text Available Ovarian cancer is second prevalent cancer among gynecologic malignancies and the most common type of ovarian cancer is epithelial form (85-90 percent. To detect the risk factors for the epithelial ovarian cancer, a case-control study was conducted in Valieasr hospital in 1988. In this study, 118 cases with epithelial ovarian cancer (according histological records and 240 controls without any gynecological cancer in gynecologic clinic had been interviewed. For data analysis, T-test, Chi2 test and logistic regression have been used at a =0.05 as level of significance. The mean age in cases was 50±13 and in controls was 49.9±12 years, without significant different. The mean number of pregnancies and parity in cases was less than controls, significantly (P<0.03. The mean months of breast feeding in cases was less than controls (54.9±71.2 versus 82.4±62.7 (P<0.001. The cases had a lower mean age of menarch than controls (P=0.03. 58 percent of cases and 21.3 percent of controls hadn't used any contraception methods (P=0.00001. The mean years of contraception was significantly less in cases versus controls (P<0.001. The odds ratio for epithelial ovarian cancer was 0.24 (95 percent CI: 0.13-0.48 in OCP users, 0.47 (95 percent CI: 0.005-0.43 in TL method, and was 0.41 (95 percent CI: 0.22-0.76 in other contraception methods, relative to women who hadn't used any contraception methods. This study reveals that epithelial ovarian cancer risk increases significantly with earlier menarch, decreasing number of pregnancy, deliveries duration of breast feeding and use of contraception methods. Use of contraception pill and tubal ligation method decreases risk of epithelial ovarian cancer.

  10. Reducing selection bias in case-control studies from rare disease registries.

    Science.gov (United States)

    Cole, J Alexander; Taylor, John S; Hangartner, Thomas N; Weinreb, Neal J; Mistry, Pramod K; Khan, Aneal

    2011-09-12

    In clinical research of rare diseases, where small patient numbers and disease heterogeneity limit study design options, registries are a valuable resource for demographic and outcome information. However, in contrast to prospective, randomized clinical trials, the observational design of registries is prone to introduce selection bias and negatively impact the validity of data analyses. The objective of the study was to demonstrate the utility of case-control matching and the risk-set method in order to control bias in data from a rare disease registry. Data from the International Collaborative Gaucher Group (ICGG) Gaucher Registry were used as an example. A case-control matching analysis using the risk-set method was conducted to identify two groups of patients with type 1 Gaucher disease in the ICGG Gaucher Registry: patients with avascular osteonecrosis (AVN) and those without AVN. The frequency distributions of gender, decade of birth, treatment status, and splenectomy status were presented for cases and controls before and after matching. Odds ratios (and 95% confidence intervals) were calculated for each variable before and after matching. The application of case-control matching methodology results in cohorts of cases (i.e., patients with AVN) and controls (i.e., patients without AVN) who have comparable distributions for four common parameters used in subject selection: gender, year of birth (age), treatment status, and splenectomy status. Matching resulted in odds ratios of approximately 1.00, indicating no bias. We demonstrated bias in case-control selection in subjects from a prototype rare disease registry and used case-control matching to minimize this bias. Therefore, this approach appears useful to study cohorts of heterogeneous patients in rare disease registries.

  11. A prevalence-based association test for case-control studies.

    Science.gov (United States)

    Ryckman, Kelli K; Jiang, Lan; Li, Chun; Bartlett, Jacquelaine; Haines, Jonathan L; Williams, Scott M

    2008-11-01

    Genetic association is often determined in case-control studies by the differential distribution of alleles or genotypes. Recent work has demonstrated that association can also be assessed by deviations from the expected distributions of alleles or genotypes. Specifically, multiple methods motivated by the principles of Hardy-Weinberg equilibrium (HWE) have been developed. However, these methods do not take into account many of the assumptions of HWE. Therefore, we have developed a prevalence-based association test (PRAT) as an alternative method for detecting association in case-control studies. This method, also motivated by the principles of HWE, uses an estimated population allele frequency to generate expected genotype frequencies instead of using the case and control frequencies separately. Our method often has greater power, under a wide variety of genetic models, to detect association than genotypic, allelic or Cochran-Armitage trend association tests. Therefore, we propose PRAT as a powerful alternative method of testing for association.

  12. Should Controls With Respiratory Symptoms Be Excluded From Case-Control Studies of Pneumonia Etiology? Reflections From the PERCH Study.

    Science.gov (United States)

    Higdon, Melissa M; Hammitt, Laura L; Deloria Knoll, Maria; Baggett, Henry C; Brooks, W Abdullah; Howie, Stephen R C; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; Murdoch, David R; Scott, J Anthony G; Thea, Donald M; Driscoll, Amanda J; Karron, Ruth A; Park, Daniel E; Prosperi, Christine; Zeger, Scott L; O'Brien, Katherine L; Feikin, Daniel R

    2017-06-15

    Many pneumonia etiology case-control studies exclude controls with respiratory illness from enrollment or analyses. Herein we argue that selecting controls regardless of respiratory symptoms provides the least biased estimates of pneumonia etiology. We review 3 reasons investigators may choose to exclude controls with respiratory symptoms in light of epidemiologic principles of control selection and present data from the Pneumonia Etiology Research for Child Health (PERCH) study where relevant to assess their validity. We conclude that exclusion of controls with respiratory symptoms will result in biased estimates of etiology. Randomly selected community controls, with or without respiratory symptoms, as long as they do not meet the criteria for case-defining pneumonia, are most representative of the general population from which cases arose and the least subject to selection bias. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  13. Laryngeal sarcoidosis: a case-control study.

    Science.gov (United States)

    Duchemann, Boris; Lavolé, Armelle; Naccache, Jean-Marc; Nunes, Hilario; Benzakin, Sylvain; Lefevre, Marine; Kambouchner, Marianne; Périé, Sophie; Valeyre, Dominique; Cadranel, Jacques

    2014-10-20

    We undertook a study on a series of laryngeal sarcoidosis (LS), a very rare and often threatening localization to better specify laryngeal manifestations, sarcoidosis clinical expression and long-term follow-up. This was a retrospective case-control study. All LS patients from two French centers were included and compared to sarcoidosis patients without laryngeal localization with two controls for one patient. Twelve consecutive LS patients were recruited between 1993 and 2011. LS revealed sarcoidosis in eight cases (67%). The most common symptoms were hoarseness (77%), inspiratory dyspnea (38%) and dysphagia (38%). Epidemiological characterisics were not different. Extrapulmonary localizations were significantly more common in LS patients than in controls (92% vs. 54%, p=0.02), particularly lupus pernio (25% vs. 0%, p=0.03) and nasosinusal involvement (83% vs. 4%, p<0.01) while thoracic involvement was less frequent (58% vs 100%, p < 0.01). Treatment rates were higher in the LS group (92% vs. 58%, p=0.04), and treatment duration was longer (median: 81 vs. 13 months, p=0.04), with frequent long-term treatment (67%, N=8/12). Two patients underwent surgery. One patient needed temporary tracheostomy during the course of the disease; Remission rates were lower in LS patients (9% vs. 58% at 2 years p<0.01). Eventually, there was no death nor definitive tracheotomy. LS is a rare condition that is often associated to other loco-regional localizations. LS are often difficult to manage. Survival is good but may require a medico-surgical approach.

  14. Case-control study of gadodiamide-related nephrogenic systemic fibrosis

    DEFF Research Database (Denmark)

    Marckmann, Peter; Skov, Lone; Rossen, Kristian

    2007-01-01

    exposed to gadodiamide develop nephrogenic systemic fibrosis. METHODS: We conducted a case-control study of 19 histologically verified cases and 19 sex- and age-matched controls. All subjects had chronic renal failure when exposed to gadodiamide. Clinical, biochemical and pharmacological data were.......02). CONCLUSIONS: Increasing cumulative gadodiamide exposure, high-dose epoietin-beta treatment, and higher serum concentrations of ionized calcium and phosphate increase the risk of gadodiamide-related nephrogenic systemic fibrosis in renal failure patients. Severe cases seem to develop primarily among patients......BACKGROUND: Nephrogenic systemic fibrosis may be caused by gadolinium (Gd)-containing magnetic resonance imaging contrast agents. Most reported cases were associated with one particular agent, gadodiamide. Yet, unidentified cofactors might explain why only a minority of renal failure patients...

  15. Reducing selection bias in case-control studies from rare disease registries

    Directory of Open Access Journals (Sweden)

    Mistry Pramod K

    2011-09-01

    Full Text Available Abstract Background In clinical research of rare diseases, where small patient numbers and disease heterogeneity limit study design options, registries are a valuable resource for demographic and outcome information. However, in contrast to prospective, randomized clinical trials, the observational design of registries is prone to introduce selection bias and negatively impact the validity of data analyses. The objective of the study was to demonstrate the utility of case-control matching and the risk-set method in order to control bias in data from a rare disease registry. Data from the International Collaborative Gaucher Group (ICGG Gaucher Registry were used as an example. Methods A case-control matching analysis using the risk-set method was conducted to identify two groups of patients with type 1 Gaucher disease in the ICGG Gaucher Registry: patients with avascular osteonecrosis (AVN and those without AVN. The frequency distributions of gender, decade of birth, treatment status, and splenectomy status were presented for cases and controls before and after matching. Odds ratios (and 95% confidence intervals were calculated for each variable before and after matching. Results The application of case-control matching methodology results in cohorts of cases (i.e., patients with AVN and controls (i.e., patients without AVN who have comparable distributions for four common parameters used in subject selection: gender, year of birth (age, treatment status, and splenectomy status. Matching resulted in odds ratios of approximately 1.00, indicating no bias. Conclusions We demonstrated bias in case-control selection in subjects from a prototype rare disease registry and used case-control matching to minimize this bias. Therefore, this approach appears useful to study cohorts of heterogeneous patients in rare disease registries.

  16. Suspected survivor bias in case-control studies: stratify on survival time and use a negative control.

    Science.gov (United States)

    van Rein, Nienke; Cannegieter, Suzanne C; Rosendaal, Frits R; Reitsma, Pieter H; Lijfering, Willem M

    2014-02-01

    Selection bias in case-control studies occurs when control selection is inappropriate. However, selection bias due to improper case sampling is less well recognized. We describe how to recognize survivor bias (i.e., selection on exposed cases) and illustrate this with an example study. A case-control study was used to analyze the effect of statins on major bleedings during treatment with vitamin K antagonists. A total of 110 patients who experienced such bleedings were included 18-1,018 days after the bleeding complication and matched to 220 controls. A protective association of major bleeding for exposure to statins (odds ratio [OR]: 0.56; 95% confidence interval: 0.29-1.08) was found, which did not become stronger after adjustment for confounding factors. These observations lead us to suspect survivor bias. To identify this bias, results were stratified on time between bleeding event and inclusion, and repeated for a negative control (an exposure not related to survival): blood group non-O. The ORs for exposure to statins increased gradually to 1.37 with shorter time between outcome and inclusion, whereas ORs for the negative control remained constant, confirming our hypothesis. We recommend the presented method to check for overoptimistic results, that is, survivor bias in case-control studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Risk factors associated with lipomyelomeningocele: a case-control study.

    Science.gov (United States)

    Esmaeili, Arash; Hanaei, Sara; Fadakar, Kaveh; Dadkhah, Sahar; Arjipour, Mahdi; Habibi, Zohreh; Nejat, Farideh; El Khashab, Mostafa

    2013-01-01

    In general, it seems that both genetic and environmental factors play important roles in the induction of neural tube defects. Lipomyelomeningocele (LipoMMC) is a rather common type of closed neural tube defect, but only limited studies have investigated the potential risk factors of this anomaly. Therefore, the purpose of this case-control study was to investigate the risk factors involved in LipoMMC formation. Various risk factors were evaluated in 35 children between 1 month and 10 years of age with LipoMMC in a hospital-based case-control study. The 2 control arms consisted of 35 children with myelomeningocele (MMC group) and 35 children with congenital anomalies other than central nervous system problems (control group). All groups were matched for age and visited the same hospital. A structured questionnaire was used for the collection of all data, including the mothers' weight and height during pregnancy, education, reproductive history, previous abortions, and socioeconomic status, as well as the parents' consanguinity and family history of the same anomalies. Univariate analysis of the children with LipoMMC compared to the control group showed that the use of periconceptional folic acid supplementation was significantly lower in the MMC and LipoMMC groups compared to the control group. In addition, comparison of the MMC and control groups revealed statistically significant differences regarding the use of folic acid and maternal obesity. In multivariate analysis, use of folic acid in the periconceptional period and during the first trimester was an independent risk factor for LipoMMC and MMC. Furthermore, maternal obesity was a significantly positive risk factor for MMC. The probable risk factors for LipoMMC were investigated in this case-control study. Consumption of folic acid in the periconceptional period and during the first trimester is an independent protective factor against LipoMMC. It seems that larger studies are needed to examine other possible

  18. Retrospective exposure assessment and quality control in an international multi-centre case-control study

    DEFF Research Database (Denmark)

    Tinnerberg, H; Heikkilä, P; Huici-Montagud, A

    2003-01-01

    The paper presents the exposure assessment method and quality control procedure used in an international, multi-centre case-control study within a joint Nordic and Italian cohort. This study was conducted to evaluate whether occupational exposure to carcinogens influenced the predictivity of high...... was higher among the original assessors (the assessor from the same country as the subject) than the average prevalence assessed by the other four in the quality control round. The original assessors classified more job situations as exposed than the others. Several reasons for this are plausible: real...... country-specific differences, differences in information available to the home assessor and the others and misunderstandings or difficulties in translation of information. To ensure the consistency of exposure assessments in international retrospective case-control studies it is important to have a well...

  19. Risk Factors Profile of Shoulder Dystocia in Oman: A Case Control Study

    OpenAIRE

    Maha M. Al-Khaduri; Rania Mohammed Abudraz; Sayed G. Rizvi; Yahya M. Al-Farsi

    2014-01-01

    Objective: This study aimed to assess the risk factor profile of shoulder dystocia and associated neonatal complications in Oman, a developing Arab country. Methods: A retrospective case-control study was conducted among 111 cases with dystocia and 111 controls, identified during 1994-2006 period in a tertiary care hospital in Oman. Controls were randomly selected among women who did not have dystocia, and were matched to cases on the day of delivery. Data related to potential risk factor...

  20. Case-control study of fetal microchimerism and breast cancer.

    Directory of Open Access Journals (Sweden)

    Vijayakrishna K Gadi

    2008-03-01

    Full Text Available Prior pregnancy is known to protect against development of breast cancer. Recent studies have demonstrated that pregnancy has the capacity to establish small numbers of immunologically active fetal-derived cells in the mother, a phenomenon known as fetal microchimerism (FMc. We asked whether presence of FMc, routinely acquired during pregnancy, is a protective factor for breast cancer.DNA extracts from peripheral blood specimens were obtained from a population-based case-control study of risk factors for breast cancer in women 21 to 45 years old. Specimens were tested with quantitative PCR for presence and concentrations of male DNA presumed to derive from prior pregnancies with a male fetus. Odds ratios (OR and 95% confidence intervals (CI were estimated with consideration of multiple established reproductive and environmental risk factors for breast cancer. FMc results were generated on 99 parous women, 54 with primary invasive breast cancer and 45 general population controls. FMc prevalence was 56% (25/45 and 26% (14/54 in controls and cases, respectively. Women harboring FMc were less likely to have had breast cancer (OR = 0.29, 95% CI 0.11-0.83; p = 0.02, adjusting for age, number of children, birth of a son, history of miscarriage, and total DNA tested. In addition, FMc concentrations were higher in controls versus cases (p = 0.01. Median concentrations were 2 (0-78 and 0 (0-374 fetal genomes/10(6 maternal genomes in controls and cases, respectively.Results suggest that the enigma of why some parous women are not afforded protection from breast cancer by pregnancy might in part be explained by differences in FMc. Mechanistic studies of FMc-derived protection against breast cancer are warranted.

  1. Dengue infection and miscarriage: a prospective case control study.

    Directory of Open Access Journals (Sweden)

    Peng Chiong Tan

    Full Text Available BACKGROUND: Dengue is the most prevalent mosquito borne infection worldwide. Vertical transmissions after maternal dengue infection to the fetus and pregnancy losses in relation to dengue illness have been reported. The relationship of dengue to miscarriage is not known. METHOD: We aimed to establish the relationship of recent dengue infection and miscarriage. Women who presented with miscarriage (up to 22 weeks gestation to our hospital were approached to participate in the study. For each case of miscarriage, we recruited 3 controls with viable pregnancies at a similar gestation. A brief questionnaire on recent febrile illness and prior dengue infection was answered. Blood was drawn from participants, processed and the frozen serum was stored. Stored sera were thawed and then tested in batches with dengue specific IgM capture ELISA, dengue non-structural protein 1 (NS1 antigen and dengue specific IgG ELISA tests. Controls remained in the analysis if their pregnancies continued beyond 22 weeks gestation. Tests were run on 116 case and 341 control sera. One case (a misdiagnosed viable early pregnancy plus 45 controls (39 lost to follow up and six subsequent late miscarriages were excluded from analysis. FINDINGS: Dengue specific IgM or dengue NS1 antigen (indicating recent dengue infection was positive in 6/115 (5·2% cases and 5/296 (1·7% controls RR 3·1 (95% CI 1·0-10 P = 0·047. Maternal age, gestational age, parity and ethnicity were dissimilar between cases and controls. After adjustments for these factors, recent dengue infection remained significantly more frequently detected in cases than controls (AOR 4·2 95% CI 1·2-14 P = 0·023. INTERPRETATION: Recent dengue infections were more frequently detected in women presenting with miscarriage than in controls whose pregnancies were viable. After adjustments for confounders, the positive association remained.

  2. Qat use and esophageal cancer in Ethiopia: A pilot case-control study.

    Directory of Open Access Journals (Sweden)

    Maria E Leon

    Full Text Available Qat (Catha edulis chewing is reported to induce lesions in the buccal mucosa, irritation of the esophagus, and esophageal reflux. Case series suggest a possible etiological role in oral and esophageal cancers. This pilot study aimed to generate preliminary estimates of the magnitude and direction of the association between qat use and esophageal cancer (EC risk and to inform the logistics required to conduct a multi-center case-control study.Between May 2012 and May 2013, 73 EC cases (including 12 gastro-esophageal junction cases and 133 controls matched individually on sex, age, and residence were enrolled at two endoscopy clinics and a cancer treatment hospital in Addis Ababa. A face-to-face structured questionnaire was administered. Qat use was defined as ever having chewed qat once a week or more frequently for at least one year. Odds ratios were calculated using conditional logistic regression.Only 8% of cases resided in Addis Ababa. Qat use was more frequent in cases (36% than in controls (26%. A 2-fold elevation in EC risk was observed in ever qat chewers compared with never users in unadjusted conditional logistic regression (OR = 2.12; 95% CI = 0.94, 4.74, an association that disappeared after adjusting for differences in tobacco use, consumption of alcohol and green vegetables, education level, and religion (OR = 0.95; 0.22, 4.22. Among never tobacco users, however, a non-significant increase in EC risk was suggested in ever qat users also after adjustment. Increases in EC risk were observed with ever tobacco use, alcohol consumption, low consumption of green vegetables, a salty diet, illiteracy, and among Muslims; the four latter associations were significant.This pilot study generated EC risk estimates in association with a habit practiced by millions of people and never before studied in a case-control design. Results must be interpreted cautiously in light of possible selection bias, with some demographics such as education level

  3. Analgesics use and ESRD in younger age: a case-control study

    Directory of Open Access Journals (Sweden)

    Moehner Sabine

    2007-12-01

    Full Text Available Abstract Background An ad hoc peer-review committee was jointly appointed by Drug Authorities and Industry in Germany, Austria and Switzerland in 1999/2000 to review the evidence for a causal relation between phenacetin-free analgesics and nephropathy. The committee found the evidence as inconclusive and requested a new case-control study of adequate design. Methods We performed a population-based case-control study with incident cases of end-stage renal disease (ESRD under the age of 50 years and four age and sex-matched neighborhood controls in 170 dialysis centers (153 in Germany, and 17 in Austria from January 1, 2001 to December 31, 2004. Data on lifetime medical history, risk factors, treatment, job exposure and intake of analgesics were obtained in a standardized face-to-face interview using memory aids to enhance accuracy. Study design, study performance, analysis plan, and study report were approved by an independent international advisory committee and by the Drug Authorities involved. Unconditional logistic regression analyses were performed. Results The analysis included 907 cases and 3,622 controls who had never used phenacetin-containing analgesics in their lifetime. The use of high cumulative lifetime dose (3rd tertile of analgesics in the period up to five years before dialysis was not associated with later ESRD. Adjusted odds ratios with 95% confidence intervals were 0.8 (0.7 – 1.0 and 1.0 (0.8 – 1.3 for ever- compared with no or low use and high use compared with low use, respectively. The same results were found for all analgesics and for mono-, and combination preparations with and without caffeine. No increased risk was shown in analyses stratifying for dose and duration. Dose-response analyses showed that analgesic use was not associated with an increased risk for ESRD up to 3.5 kg cumulative lifetime dose (98 % of the cases with ESRD. While the large subgroup of users with a lifetime dose up to 0.5 kg (278 cases and

  4. Obstacles to action in arthritis: a community case-control study.

    Science.gov (United States)

    Hutton, Ingrid; Gamble, Greg; McLean, Grant; Butcher, Hugh; Gow, Peter; Dalbeth, Nicola

    2009-07-01

    Despite the benefits of physical activity, people with arthritis are less active than the general population. The aim of this study was to determine the motivators and obstacles to physical activity for adults with arthritis. Participants were identified from the Obstacles to Action Study, a community based study of 8163 adults, which explored barriers and motivators to physical activity. A 1:1 case-control study was designed; cases were identified as those participants who reported arthritis (n = 1106). Each case was matched with an age, sex and ethnicity-matched non-arthritis control (n = 1106). Cases were less likely to achieve recommended physical activity targets (58.8% vs. 68.1% P = 0.00001). Furthermore, fewer people with arthritis believed that physical activity would help them lead healthy lives (86.7% vs. 91.3% P = 0.006) or viewed physical activity as a priority (53.8% vs. 59.8% P = 0.005). Cases were less confident in their abilities to try a new activity (37.1% vs. 43.7% P = 0.002) or maintain a healthy weight (65.0% vs. 74.3% P = 0.00001). Cases also reported greater negative impact scores for barriers to activity, particularly arthritis, accessibility, cost and discomfort while exercising. Motivators and environmental barriers to activity were similar for cases and controls. These findings persisted after adjusting for educational level, body mass index and comorbidities. People with arthritis are less active and demonstrate different attitudes toward physical activity. Although people with arthritis identify similar environmental barriers, they have different psychosocial barriers. In order to design effective physical activity programs for people with arthritis, these barriers must be specifically addressed.

  5. Periodontal disease and spontaneous preterm birth: a case control study

    Directory of Open Access Journals (Sweden)

    Eley Barry

    2006-07-01

    Full Text Available Abstract Background Several studies have suggested an association between periodontal disease and prematurity but this finding has not been consistently observed. Methods Case control study. Cases (n = 50 were women who had delivered after spontaneous preterm labor at Results There was no difference in the proportion of sites with significant attachment loss (≥3 mm: Cases-3.2%, Controls-2.2% p = 0.21. The gingival crevicular fluid concentrations of elastase and gingipain were elevated in cases vs. controls 238.8 uU/ul vs. 159.6 uU/ul p = .007 and 2.70 uU/ul vs. 1.56 uU/ul p = .001. On multivariate analysis, the mean log concentration of elastase, but not of gingipain, remained a significant predictor of preterm labor p = .0.015. Conclusion We found no evidence that clinical periodontal disease is associated with spontaneous preterm birth. Elevated gingival crevicular fluid levels of elastase were associated with preterm birth but further research is needed before this can be assumed to be a causal relationship.

  6. External radiotherapy prior to thyroid cancer: A case-control study

    International Nuclear Information System (INIS)

    Hallquist, A.; Loefroth, P.O.; Hardell, L.

    1993-01-01

    The aim of this investigation was to study previous radiotherapy of malignant diseases as a risk factor for thyroid cancer. By using the Swedish Cancer Registry all cases of thyroid cancer with another malignant disease at least one year previously and living within the catchment area of the hospital were traced. During 1959-1989 a total of 1056 cases of thyroid cancer were identified. Of these, 37 had had another previous malignant disease and they constituted the cases in this study. As controls four persons with at least two malignant diseases, thyroid cancer excluded, were selected for each case from the same cancer registry. Ten (27.0%) of the 37 patients with thyroid cancer as a second tumor had earlier been irradiated with the treatment dose including the thyroid gland as compared with 34 (24.5%) of the 139 control patients. Eight of the ten cases with previous irradiation of the thyroid gland had papillary cancer. The median latency was 13 years. The estimated radiation dose in the thyroid varied between 3 and 40 Gy. External radiotherapy gave a crude odds ratio of 1.1 with 95% confidence interval = 0.5-2.8 for thyroid cancer. The weighted odds ratio was calculated to 2.3 with confidence interval = 0.5-8.9. This case-control study gave a nonsignificantly increased odds ratio for thyroid cancer in patients with external radiotherapy including the thyroid gland. 26 refs., 4 tabs

  7. Nutritional risk assessment for Hip fracture, A Case control study

    OpenAIRE

    Torbergsen, Anne Cathrine

    2016-01-01

    The study was conducted at Oslo University Hospital, Norway. Patients were included from September 2009 until April 2011. In total 116 patients and 73 healthy non-fractured controls participated. The study has 3 parts. In the first part, we studied micronutrients and the risk of hip fracture in a case control study. In the second part, we conducted a randomized controlled nutrition intervention trial and finally, in the third part, we studied if micronutrients were associated with delirium in...

  8. Risk Factors For Ectopic Pregnancy : A Case Control Study

    Directory of Open Access Journals (Sweden)

    Deshmukh J.S

    1999-01-01

    Full Text Available Research question: Which are the risk factors for ectopic pregnancy . Objective: To study the strength of association between hypothesised risk factors and ectopic pregnancy. Study design: Unmatched case- control study. Setting: Government Medical College, Hospital, Nagpur. Participants: 133 cases of ectopic pregnancy and equal number of controls (non pregnant women admitted to study hospital. Study variables : Pelvic inflammatory diseases, sexually transmitted diseases, IUD use at conception , past use of IUD, prior ectopic pregnancy, OC pills use at the time of conception, past use of OC pills, induced abortion, spontaneous abortion, infertility and pelvic and abdominal surgery. Statistical analysis: Odds ratios & their 95% CI, Pearson’s chi square test, unconditional logistic regression analysis and population attributable risk proportion. Results : Use of IUD at conception, prior ectopic pregnancy , pelvic inflammatory disease, sexually transmitted diseases, infertility, OC pills use at the time of conception, past use of IUD and induced abortion were found to be significantly associated with ectopic pregnancy. Conclusion: Identification of these risk factors for etopic pregnancy shall help in early detection and appropriate management in an individual case and it may help in devising a comprehensive preventive strategy for ectopic pregnancy

  9. Response rates in case-control studies of cancer by era of fieldwork and by characteristics of study design.

    Science.gov (United States)

    Xu, Mengting; Richardson, Lesley; Campbell, Sally; Pintos, Javier; Siemiatycki, Jack

    2018-04-09

    The purpose of this study was to describe time trends in response rates in case-control studies of cancer and identify study design factors that influence response rate. We reviewed 370 case-control studies of cancer published in 12 journals during indicator years in each of the last four decades. We estimated time trends of response rates and reasons for nonresponse in each of the following types of study subjects: cases, medical source controls, and population controls. We also estimated response rates according to characteristics of study context. Median response rates among cases and population controls were between 75% and 80% in the 1970s. Between 1971 and 2010, study response rates declined by 0.31% per year for cases and 0.78% for population controls. Only a minority of studies reported reasons for nonparticipation; subject refusal was the most common reported reason. Studies conducted in North America had lower median response rates than studies conducted in Europe. In-person and telephone interviews elicited higher response rates than mail questionnaires. Response rates from case-control studies of cancer have declined, and this could threaten the validity of results derived from these studies. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Violence against Women and Gastroschisis: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Daniel Ruiz

    2013-10-01

    Full Text Available Background: Gastroschisis, a birth defect characterized by herniated fetal abdominal wall, occurs more commonly in infants born to teenage and young mothers. Ischemia of the vascular vitelline vessels is the likely mechanism of pathogenesis. Given that chronic stress and violence against women are risk factors for cardiovascular disease we explored whether these may represent risk factors for gastroschisis, when they occur during pregnancy. A case-control study was conducted, with 15 incident cases of children born with gastroschisis in the Region of Murcia, Spain, from December 2007 to June 2013. Forty concurrent controls were recruited at gestation weeks 20–24 or post-partum. All mothers of cases and controls completed a comprehensive, in-person, ‘green sheet’ questionnaire on environmental exposures. Results: Mothers of children with gastroschisis were younger, smoked more cigarettes per week relative to controls, were exposed to higher amounts of illegal drugs, and suffered from domestic violence more frequently than the controls. Multivariable logistic regression analysis highlights periconceptional ‘gender-related violence’ (OR: 16.6, 95% CI 2.7 to 101.7 and younger maternal age (OR 1.1, 95% CI 1.0–1.3. Conclusions: Violence against pregnant women is associated with birth defects, and should be studied in more depth as a cause-effect teratogenic. Psychosocial risk factors, including gender-based violence, are important for insuring the health and safety of the pregnant mother and the fetus.

  11. Sample size calculations for case-control studies

    Science.gov (United States)

    This R package can be used to calculate the required samples size for unconditional multivariate analyses of unmatched case-control studies. The sample sizes are for a scalar exposure effect, such as binary, ordinal or continuous exposures. The sample sizes can also be computed for scalar interaction effects. The analyses account for the effects of potential confounder variables that are also included in the multivariate logistic model.

  12. Drug and alcohol crash risk : a case-control study.

    Science.gov (United States)

    2016-12-01

    This study used a case-control design to estimate the risk of crashes involving drivers using drugs, alcohol or both. Data was collected in Virginia Beach, Virginia, for 20 months. The study obtained biological measures on more than 3,000 crash...

  13. Role of nutrition in pre-eclampsia and eclampsia cases, a case control study

    Directory of Open Access Journals (Sweden)

    Punyatoya Bej

    2014-12-01

    Full Text Available Background: Preeclampsia and eclampsia during pregnancy contribute to maternal and fetal morbidity as well as mortality. The identification of the role of maternal nutrition during pregnancy will help in reducing morbidity and mortality. Aims & Objective: The objective of this study is to find out the role of nutrition, in the form of total calorie, protein, fruits, iron, folic acid and calcium intake in the development of preeclampsia and eclampsia among pregnant women in a tertiary level hospital. Material Methods: After ethical approval and informed consent, 122 women who delivered beyond 22 weeks of gestation and diagnosed as preeclampsia or eclampsia were selected. Simultaneously, 122 controls with no diagnosis of preeclampsia or eclampsia were selected from the post natal ward. Cases and controls were administered the same pre-tested questionnaire containing questions related to food and micronutrient intake by cases and control. Results: Logistic regression was applied in the statistical analysis. The factors that were found to be significant predictors of risk for development of preeclampsia and eclampsia were higher calorie intake (adjusted Odds Ratio (OR 14.12 [6.41-43.23] P < 0.001, less protein intake (adjusted OR 3.87 [1.97-8.01] P < 0.001 during pregnancy. Fruits intake in both cases and controls were similar. 77.9% of cases and 84.4% of controls had taken iron tablets during their antenatal period. 75.4% of cases and 82.8% of controls had taken calcium tablets during their antenatal period. Iron and calcium intake is not significantly associated with development of preeclampsia and eclampsia. Conclusion: Higher calorie intake and less protein intake during pregnancy were associated with development of preeclampsia and eclampsia. Fruits intake, iron and calcium intake were not associated with development of preeclampsia and eclampsia

  14. Risk factors for gallbladder cancer: a case-control study.

    Science.gov (United States)

    Jain, Kajal; Sreenivas, V; Velpandian, T; Kapil, Umesh; Garg, Pramod Kumar

    2013-04-01

    Risk factors for gallbladder cancer (GBC) except gallstones are not well known. The objective was to study the risk factors for GBC. In a case-control study, 200 patients with GBC, 200 healthy controls and 200 gallstones patients as diseased controls were included prospectively. The risk factors studied were related to socioeconomic profile, life style, reproduction, diet and bile acids. On comparing GBC patients (mean age 51.7 years; 130 females) with healthy controls, risk factors were chemical exposure [odd ratios (OR): 7.0 (2.7-18.2); p < 0.001)], family history of gallstones [OR: 5.3 (1.5-18.9); p < 0.01)], tobacco [OR: 4.1 (1.8-9.7); p < 0.001)], fried foods [OR: 3.1 (1.7-5.6); p < 0.001], joint family [OR: 3.2 (1.7-6.2); p < 0.001], long interval between meals [OR: 1.4 (1.2-1.6); p < 0.001] and residence in Gangetic belt [OR: 3.3 (1.8-6.2); p < 0.001]. On comparing GBC cases with gallstone controls, risk factors were female gender [OR: 2.4 (1.3-4.3); p = 0.004], residence in Gangetic belt [OR: 2.3 (1.2-4.4); p = 0.012], fried foods [OR: 2.5 (1.4-4.4); p < 0.001], diabetes [OR: 2.7 (1.2-6.4); p = 0.02)], tobacco [OR 3.8 (1.7-8.1); p < 0.001)] and joint family [OR: 2.1 (1.2-3.4); p = 0.004]. The ratio of secondary to primary bile acids was significantly higher in GBC cases than gallstone controls (20.8 vs. 0.44). Fried foods, tobacco, chemical exposure, family history of gallstones, residence in Gangetic belt and secondary bile acids were significant risk factors for GBC. Copyright © 2012 UICC.

  15. A case-control study of risk factors for male infertility in Southern ...

    African Journals Online (AJOL)

    Aim: The purpose of this study was to evaluate the association between selected potential socio-demographic and behavioural risk factors and infertility in Nigeria males. Methods: The study consisted of cases and controls. The cases were 150 males with proven male infertility, while the controls were 150 fertile males with ...

  16. Case-Control Studies of Sporadic Enteric Infections: A Review and Discussion of Studies Conducted Internationally from 1990 to 2009

    Science.gov (United States)

    Fullerton, Kathleen E.; Scallan, Elaine; Kirk, Martyn D.; Mahon, Barbara E.; Angulo, Frederick J.; de Valk, Henriette; van Pelt, Wilfrid; Gauci, Charmaine; Hauri, Anja M.; Majowicz, Shannon; O’Brien, Sarah J.

    2015-01-01

    Epidemiologists have used case-control studies to investigate enteric disease outbreaks for many decades. Increasingly, case-control studies are also used to investigate risk factors for sporadic (not outbreak-associated) disease. While the same basic approach is used, there are important differences between outbreak and sporadic disease settings that need to be considered in the design and implementation of the case-control study for sporadic disease. Through the International Collaboration on Enteric Disease “Burden of Illness” Studies (the International Collaboration), we reviewed 79 case-control studies of sporadic enteric infections caused by nine pathogens that were conducted in 22 countries and published from 1990 through to 2009. We highlight important methodological and study design issues (including case definition, control selection, and exposure assessment) and discuss how approaches to the study of sporadic enteric disease have changed over the last 20 years (e.g., making use of more sensitive case definitions, databases of controls, and computer-assisted interviewing). As our understanding of sporadic enteric infections grows, methods and topics for case-control studies are expected to continue to evolve; for example, advances in understanding of the role of immunity can be used to improve control selection, the apparent protective effects of certain foods can be further explored, and case-control studies can be used to provide population-based measures of the burden of disease. PMID:22443481

  17. Association of Serum Uric Acid with Preeclampsia: A Case Control Study

    Directory of Open Access Journals (Sweden)

    Razia Sultana

    2013-07-01

    Full Text Available Background: Preeclampsia (PE is still one of the important causes of maternal and fetal mortality in Bangladesh. Many researches have been done to identify a unique screening test that would predict the risk of developing PE before the classic symptoms appear. One of the most accessible and easiest screening tests is serum uric acid measurement. Numerous studies have demonstrated a relation between elevated maternal serum uric acid levels and adverse maternal and fetal outcome. Among several pathophysiologic factors the most commonly accepted explanation for hyperuricemia in PE is increased reabsorption and decreased excretion of uric acid.Objective: The aim of the present study was to assess the association of serum uric acid with preeclampsia.Materials and method: A case control study was conducted in the department of Biochemistry, Dhaka Medical College, Dhaka from July 2010 to June 2011. A total number of 100 pregnant women in third trimester of pregnancy attending in Obstetrics and Gynaecology department of Dhaka Medical College Hospital were selected purposively as study subjects. Among them 50 pregnant women with preeclampsia were selected as cases and 50 normal healthy pregnant women as controls.Results: Most of the study subjects were within 21 – 30 years of age group and mean age in case and control was 24.06±3.71 and 24.66±3.22 years respectively, which was not statistically different. Mean gestational age in case and control was 33.50±2.55 weeks and 33.60±2.95 weeks respectively, which was also not statistically different. Among the study subjects majority was primi in both groups (case 76%, contol 58% showing no statistical significance. Majority of the subjects in both groups were irregular in their antenatal checkup (case 52%, contol 40%. Uric acid concentration was measured in all the study subjects. The mean serum uric acid concentration in cases and controls were 7.01±1.90 mg/dl and 4.55±1.63 mg/dl respectively. This

  18. Brain-relevant antibodies in first-episode psychosis: a matched case-control study.

    Science.gov (United States)

    Gaughran, Fiona; Lally, John; Beck, Katherine; McCormack, Ruaidhri; Gardner-Sood, Poonam; Coutinho, Ester; Jacobson, Leslie; Lang, Bethan; Sainz-Fuertes, Ricardo; Papanastasiou, Evangelos; Di Forti, Marta; Nicholson, Tim; Vincent, Angela; Murray, Robin M

    2018-06-01

    There has been much recent excitement about the possibility that some cases of psychosis may be wholly due to brain-reactive antibodies, with antibodies to N-methyl-D-aspartate receptor (NMDAR) and the voltage-gated potassium channel (VGKC)-complex reported in a few patients with first-episode psychosis (FEP). Participants were recruited from psychiatric services in South London, UK, from 2009 to 2011 as part of the Genetics and Psychosis study. We conducted a case-control study to examine NMDAR and VGKC-complex antibody levels and rates of antibody positivity in 96 patients presenting with FEP and 98 controls matched for age and sex. Leucine-rich glioma inactiviated-1 (LGI1) and contactin-associated protein (CASPR) antibodies were also measured. Notably, patients with suspicion of organic disease were excluded. VGKC-complex antibodies were found in both cases (n = 3) and controls (n = 2). NMDAR antibody positivity was seen in one case and one control. Either LGI1-Abs or CASPR2-Abs were found in three cases and three controls. Neuronal antibody staining, consistent with the above results or indicating potential novel antigens, was overall positive in four patients but also in six controls. Overall, antibody positivity was at low levels only and not higher in cases than in controls. This case-control study of the prevalence of antibodies in FEP does not provide evidence to support the hypothesis that FEP is associated with an immune-mediated process in a subgroup of patients. Nevertheless, as other bio-clinical factors may influence the effect of such antibodies in a given individual, and patients with organic neurological disease may be misdiagnosed as FEP, the field requires more research to put these findings in context.

  19. Aetiology of handball injuries : a case-control study

    NARCIS (Netherlands)

    Dirx, M.; Bouter, L. M.; de Geus, G. H.

    This article presents the results of a case-control study regarding the background to handball injuries among players of 12 years and older. Data were collected by means of a written questionnaire on the nature, location and direct causes of the injuries as well as information on risk factors.

  20. Misclassification of Case-Control Studies in Neurosurgery and Proposed Solutions.

    Science.gov (United States)

    Esene, Ignatius Ngene; Mbuagbaw, Lawrence; Dechambenoit, Gilbert; Reda, Wael; Kalangu, Kazadi K

    2018-04-01

    Case-control studies (CCS) and cohort studies (CS) are common research designs in neurosurgery. But the term case-control study is frequently misused in the neurosurgical literature, with many articles reported as CCS, even although their methodology does not respect the basic components of a CCS. We sought to estimate the extent of these discrepancies in neurosurgical literature, explore factors contributing to mislabeling, and shed some light on study design reporting. We identified 31 top-ranking pure neurosurgical journals and searched them for articles reported as CCS, either in the title or in the abstract. The articles were read to determine if they really were CCS according to STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. Article assessment was conducted in duplicate (agreement [κ statistics] = 99.82%). Two hundred and twenty-four articles met our inclusion criteria, 133 of which (59.38%) correctly labeled the case-control design, whereas 91 (40.62%) misclassified this study design. Cohort studies (CS) were the most common design mislabeled as case-control studies in 76 articles (33.93%), 57 of which (25.45%) were retrospective CS. The mislabeling of CCS impairs the appropriate indexing, classification, and sorting of evidence. Mislabeling CS for CCS leads to a downgrading of evidence as CS represent the highest level of evidence for observational studies. Odds ratios instead of relative risk are reported for these studies, resulting in a distortion of the measurement of the effect size, compounded when these are summarized in systematic reviews and pooled in meta-analyses. Many studies reported as CCS are not true CCS. Reporting guidelines should include items that ensure that studies are labeled correctly. STROBE guidelines should be implemented in assessment of observational studies. Researchers in neurosurgery need better training in research methods and terminology. We also recommend accrued vigilance from

  1. Exposure to pistachio pesticides and stillbirth: a case-control study.

    Science.gov (United States)

    Razi, Saeid; Rezaeian, Mohsen; Dehkordi, Fatemeh Ghani; Manshoori, Azita; Goujani, Reza; Vazirinejad, Reza

    2016-01-01

    Stillbirth is an undesirable outcome of pregnancy. In light of the increasing use of pesticides and growing concerns about the possible health effects of agricultural pesticides, we investigated the effect of exposure to pistachio pesticides on stillbirth in pregnant mothers. This case-control study was conducted in Rafsanjan, Iran from 2011 to 2012. A total of 125 females who had a recent stillbirth were included as the case group, and 250 controls were selected from females who had a recent live birth. For each case, two controls with the nearest propensity score to the case were selected. Data were collected using a protocol developed by the researcher that involved interviewing respondents and reviewing their medical records. Conditional multivariate and univariate logistic regression analysis were performed and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. The ORs of stillbirth in mothers living in pistachio gardens and those who were exposed to sprayed pesticides, in comparison to the controls, were 14.1 (95% CI, 3.3 to 63.4) and 5.0 (95% CI, 1.2 to 28.6), respectively. No significant differences were found in stillbirth rates according to the distance between the mother's residence and a pistachio garden or involvement in agricultural activities. The results of our study showed that exposure to pistachio pesticides during pregnancy may increase the likelihood of stillbirth in mothers.

  2. Risk factors for measles among adults in Tianjin, China: Who should be controls in a case-control study?

    Science.gov (United States)

    Wagner, Abram L; Boulton, Matthew L; Gillespie, Brenda W; Zhang, Ying; Ding, Yaxing; Carlson, Bradley F; Luo, Xiaoyan; Montgomery, JoLynn P; Wang, Xiexiu

    2017-01-01

    Control groups in previous case-control studies of vaccine-preventable diseases have included people immune to disease. This study examines risk factors for measles acquisition among adults 20 to 49 years of age in Tianjin, China, and compares findings using measles IgG antibody-negative controls to all controls, both IgG-negative and IgG-positive. Measles cases were sampled from a disease registry, and controls were enrolled from community registries in Tianjin, China, 2011-2015. Through a best subsets selection procedure, we compared which variables were selected at different model sizes when using IgG-negative controls or all controls. We entered risk factors for measles in two separate logistic regression models: one with measles IgG-negative controls and the other with all controls. The study included 384 measles cases and 1,596 community controls (194 IgG-negative). Visiting a hospital was an important risk factor. For specialty hospitals, the odds ratio (OR) was 4.53 (95% confidence interval (CI): 1.28, 16.03) using IgG-negative controls, and OR = 5.27 (95% CI: 2.73, 10.18) using all controls. Variables, such as age or length of time in Tianjin, were differentially selected depending on the control group. Individuals living in Tianjin ≤3 years had 2.87 (95% CI: 1.46, 5.66) times greater odds of measles case status compared to all controls, but this relationship was not apparent for IgG-negative controls. We recommend that case-control studies examining risk factors for infectious diseases, particularly in the context of transmission dynamics, consider antibody-negative controls as the gold standard.

  3. [Application of nested case-control study on safe evaluation of post-marketing traditional Chinese medicine injection].

    Science.gov (United States)

    Xiao, Ying; Zhao, Yubin; Xie, Yanming

    2011-10-01

    The nested case-control study design (or the case-control in a cohort study) is described here as a new study design used in safe evaluation of post-marketing traditional Chinese medicine injection. In the nested case-control study, cases of a disease that occur in a defined cohort are identified and, for each, a specified number of matched controls is selected from among those in the cohort who have not developed the disease by the time of disease occurrence in the case. For many research questions, the nested case-control design potentially offers impressive reductions in costs and efforts of data collection and analysis compared with the full cohort approach, with relatively minor loss in statistical efficiency. The nested case-control design is particularly advantageous for studies in safe evaluation of post-marketing traditional Chinese medicine injection. Some examples of the application of nested case-control study were given.

  4. Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

    2016-01-01

    Background Leptospira can be found in soil. However, it is unclear whether occupational exposure to soil may represent a risk for Leptospira infection in humans. Therefore, we sought to determine the association of Leptospira IgG seroprevalence with the occupation of gardener, and to determine the epidemiological characteristics of gardeners associated with Leptospira exposure. Methods We performed a case-control study in 168 gardeners and 168 age- and gender-matched control subjects without gardening occupation in Durango City, Mexico. The seroprevalence of anti-Leptospira IgG antibodies in cases and controls was determined using an enzyme immunoassay. Bivariate and multivariate analyses were used to assess the association of Leptospira exposure and the characteristics of the gardeners. Results Anti-Leptospira IgG antibodies were found in 10 (6%) of 168 gardeners and in 15 (8.9%) of 168 control subjects (odds ratio (OR): 0.64; 95% confidence interval (CI): 0.28 - 1.48; P = 0.40). Multivariate analysis showed that Leptospira seropositivity was positively associated with female gender (OR: 5.82; 95% CI: 1.11 - 30.46; P = 0.03), and negatively associated with eating while working (OR: 0.21; 95% CI: 0.05 - 0.87; P = 0.03). In addition, multivariate analysis showed that high anti-Leptospira levels were associated with consumption of boar meat (OR: 28.00; 95% CI: 1.20 - 648.80; P = 0.03). Conclusions This is the first case-control study of Leptospira exposure in gardeners. Results do not support an association of Leptospira exposure with the occupation of gardener. However, further studies to confirm the lack of this association are needed. The potential role of consumption of boar meat in Leptospira infection deserves further investigation. PMID:26668679

  5. Baldness and testicular cancer: the EPSAM case-control study.

    Science.gov (United States)

    Moirano, G; Zugna, D; Grasso, C; Lista, P; Ciuffreda, L; Segnan, N; Merletti, F; Richiardi, L

    2016-03-01

    The etiology of testicular cancer is largely unexplained. Research has mainly focused on prenatal exposures, especially to sex hormones, while less attention has been paid to exposures that may act also postnatally. As baldness has been previously associated with testicular cancer risk we focused on baldness and body hairiness, which are both associated with androgen activity. We used data of the Postnatal Exposures and Male Health (EPSAM) study, a case-control study on testicular cancer conducted in the Province of Turin, Italy, involving cases diagnosed between 1997 and 2008. Information was collected using mailed questionnaires. Analyses included 255 cases and 459 controls. We calculated ORs and 95% CIs to estimate testicular cancer risk among those who developed baldness and among those with body hairiness. We found an inverse association between testicular cancer and baldness (OR: 0.67, 95% CI: 0.46-0.98) and body hairiness (OR: 0.78, 95% CI: 0.53-1.16), although the latter had wider CIs. The inverse association between baldness and testicular cancer is consistent with the results from previous studies. These results suggest that androgens activity may influence testicular cancer risk. © 2016 American Society of Andrology and European Academy of Andrology.

  6. The lack of selection bias in a snowball sampled case-control study on drug abuse.

    Science.gov (United States)

    Lopes, C S; Rodrigues, L C; Sichieri, R

    1996-12-01

    Friend controls in matched case-control studies can be a potential source of bias based on the assumption that friends are more likely to share exposure factors. This study evaluates the role of selection bias in a case-control study that used the snowball sampling method based on friendship for the selection of cases and controls. The cases selected fro the study were drug abusers located in the community. Exposure was defined by the presence of at least one psychiatric diagnosis. Psychiatric and drug abuse/dependence diagnoses were made according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) criteria. Cases and controls were matched on sex, age and friendship. The measurement of selection bias was made through the comparison of the proportion of exposed controls selected by exposed cases (p1) with the proportion of exposed controls selected by unexposed cases (p2). If p1 = p2 then, selection bias should not occur. The observed distribution of the 185 matched pairs having at least one psychiatric disorder showed a p1 value of 0.52 and a p2 value of 0.51, indicating no selection bias in this study. Our findings support the idea that the use of friend controls can produce a valid basis for a case-control study.

  7. Risk factors for idiopathic orbital inflammation: a case-control study

    NARCIS (Netherlands)

    Bijlsma, Ward R.; van Gils, Carla H.; Paridaens, Dion; Mourits, Maarten P.; Kalmann, Rachel

    2011-01-01

    Objective To identify risk factors involved in the development of idiopathic orbital inflammation (IOI). Methods Case-control study of 69 adults who had had a first episode of IOI and 296 adult controls with rhegmatogenous retinal detachment (RD) selected from three orbital centres in The

  8. A case-control study: occupational cooking and the risk of uveal melanoma

    Directory of Open Access Journals (Sweden)

    Marr Anja

    2010-10-01

    Full Text Available Abstract Background A European-wide population based case-control study (European rare cancer study undertaken in nine European countries examined risk factors for uveal melanoma. They found a positive association between cooks and the risk of uveal melanoma. In our study we examine whether cooks or people who worked in cook related jobs have an increased uveal melanoma risk. Methods We conducted a case-control study during 2002 and 2005. Overall, 1653 eligible subjects (age range: 20-74 years, living in Germany participated. Interviews were conducted with 459 incident uveal melanoma cases, 827 population controls, 180 ophthalmologist controls and 187 sibling controls. Data on occupational exposure were obtained from a self-administered postal questionnaire and a computer-assisted telephone interview. We used conditional logistic regression to estimate odds ratios adjusting for the matching factors. Results Overall, we did not observe an increased risk of uveal melanoma among people who worked as cooks or who worked in cook related jobs. When we restricted the source population of our study to the population of the Federal State of Northrhine-Westphalia, we observed an increased risk among subjects who were categorized as cooks in the cases-control analysis. Conclusion Our results are in conflict with former results of the European rare cancer study. Considering the rarity of the disease laboratory in vitro studies of human uveal melanoma cell lines should be done to analyze potential exposure risk factors like radiation from microwaves, strong light from incandescent ovens, or infrared radiation.

  9. Circulating folate levels and colorectal adenoma: a case-control study and a meta-analysis.

    Science.gov (United States)

    Park, Yeong Mi; Youn, Jiyoung; Cho, Chang Ho; Kim, Sung Hi; Lee, Jung Eun

    2017-10-01

    The relationship between folate and colorectal neoplasia remains controversial. We examined the association between serum folate concentrations and colorectal adenomas in a case-control study of Korean adults and conducted a meta-analysis. Our case-control study included 113 pairs of case and control who underwent colonoscopy and provided blood samples. We used multivariable conditional logistic regression models to obtain the odds ratios and 95% confidence interval (CIs). For meta-analysis, we identified the relevant studies by searching the PubMed database up to February 2017, included our case-control study and combined the study-specific relative risks (RRs) using a random-effects model. In this case-control study, we included 58 men and 55 women with colorectal adenomas and sex and fasting status matched the controls. We did not find any significant association between the serum folate levels and colorectal adenomas in either men or women. For meta-analysis, a total of eleven studies were included in our analysis and classified into two groups; polyp clearance group (PC) for the studies that included participants who underwent endoscopies and had their polyps removed at baseline; and no polyp clearance group (NPC) for the studies that included participants whose histories of endoscopies were unknown or who underwent their first endoscopies. Four PC (1,311 cases and 1,672 non-cases) and eight NPC studies (3,501 cases and 11,347 non-cases) were included. The combined RRs (95% CIs) comparing the bottom with the top categories of circulating folate levels were 1.07 (0.97-1.18) for the NPC group but 1.45 (1.16-1.74) for the PC group. Low circulating folate levels were associated with new adenoma formation.

  10. Association between smoking habits and acne vulgaris. A case-control study

    Directory of Open Access Journals (Sweden)

    Alice Mannocci

    2012-09-01

    Full Text Available

    Background: acne vulgaris, is one of the most common skin disorder. Previous studies about the role of smoke in the pathogenesis of acne reported contradictory results. The aim of this study was to conduct a case-control study investigating the relationship between tobacco smoking and acne.

    Methods: a case-control study was performed during the period September 2009 - February 2010. A questionnaire was administrated to each participant, to assess the association acne - smoke. Cases were outpatients of the Dermatologic Ambulatory of the “Fiorini” Hospital, Sapienza University of Rome (Italy. Controls were age and gender-matched to the cases. The ratio cases-controls was 1:2. A univariate and a multiple logistic regression analysis were conducted; Odds Ratio (OR and the relative 95% confidence interval (95%CI were assessed. The statistical significance was set at p < 0.05.

    Results: crude OR for the association acne - smoke was 7.26 (IC=2.27-23.18; adjusted OR for sex and age was 5.47 (IC=1.67-17.97. Of 93 cases, 6 had a severe grade of acne (6.5%, 19 had an intermediate grade of acne (20.4%, and 68 had a mild grade of acne (73.1%. No one of the smokers had a severe grade of acne, one had an intermediate grade of acne and 11 had mild acne; these differences are not statistically significant.

    Conclusions: the association between acne and smoke shows an increased risk (OR=7.26 with a statistically significant CI. Moreover, people ≥ 18 years of age have twice the risk compared to persons < 18 years of age (OR=2.31.

  11. Exposure to pistachio pesticides and stillbirth: a case-control study

    Directory of Open Access Journals (Sweden)

    Saeid Razi

    2016-04-01

    Full Text Available OBJECTIVES Stillbirth is an undesirable outcome of pregnancy. In light of the increasing use of pesticides and growing concerns about the possible health effects of agricultural pesticides, we investigated the effect of exposure to pistachio pesticides on stillbirth in pregnant mothers. METHODS This case-control study was conducted in Rafsanjan, Iran from 2011 to 2012. A total of 125 females who had a recent stillbirth were included as the case group, and 250 controls were selected from females who had a recent live birth. For each case, two controls with the nearest propensity score to the case were selected. Data were collected using a protocol developed by the researcher that involved interviewing respondents and reviewing their medical records. Conditional multivariate and univariate logistic regression analysis were performed and odds ratios (ORs and 95% confidence intervals (CIs were calculated. RESULTS The ORs of stillbirth in mothers living in pistachio gardens and those who were exposed to sprayed pesticides, in comparison to the controls, were 14.1 (95% CI, 3.3 to 63.4 and 5.0 (95% CI, 1.2 to 28.6, respectively. No significant differences were found in stillbirth rates according to the distance between the mother’s residence and a pistachio garden or involvement in agricultural activities. CONCLUSIONS The results of our study showed that exposure to pistachio pesticides during pregnancy may increase the likelihood of stillbirth in mothers.

  12. Campylobacteriosis in New Zealand: results of a case-control study.

    OpenAIRE

    Eberhart-Phillips, J; Walker, N; Garrett, N; Bell, D; Sinclair, D; Rainger, W; Bates, M

    1997-01-01

    STUDY OBJECTIVE: To identify and assess the contributions of major risk factors for campylobacteriosis in New Zealand. DESIGN: Case-control study. Home interviews were conducted over nine months using a standardised questionnaire to assess recent food consumption and other exposures. SETTING: Four centres in New Zealand with high notification rates of campylobacter infections--Auckland, Hamilton, Wellington, and Christchurch. PARTICIPANTS: Case patients were 621 people notified between 1 June...

  13. Risk factors for neural tube defects in Riyadh City, Saudi Arabia: Case-control study.

    Science.gov (United States)

    Salih, Mustafa A M; Murshid, Waleed R; Mohamed, Ashry Gad; Ignacio, Lena C; de Jesus, Julie E; Baabbad, Rubana; El Bushra, Hassan M

    2014-01-01

    Both genetic and non-genetic environmental factors are involved in the etiology of neural tube defects (NTD) which affect 0.5-2/1000 pregnancies worldwide. This study aimed to explore the risk factors for the development of NTD in Saudi population, and highlight identifiable and preventable causes. Similar studies are scarce in similar populations ofthe Arabian Peninsula and North Africa. This is an unmatched concurrent case-control study including NTD cases born at King Khalid University Hospital, Riyadh during a 4-year period (2002-2006). The case-control study included 25 cases and 125 controls (case: control ratio of 1:5). Years of formal education, employment, household environment (including availability of air conditioning) and rate of parental consanguinity did not differ between mothers of cases and controls. Significantly higher proportion of mothers of cases had history of stillbirth compared to control mothers (16% vs 4.1%, P=0.02). Also family history of hydrocephalus and congenital anomalies were more prevalent in cases than controls (P values=0.0000 and 0.003, respectively). There was significant protective effect of periconceptional folic acid consumption both prior to conception (OR 0.02, 95% CI 0.00-0.07) and during the first 6 weeks of conception (OR 0.13, 95% CI 0.04-0.39). Further research, including a larger cohort, is required to enable ascertainment of gene-nutrient and gene environment interactions associated with NTD in Saudi Arabia.

  14. Potential risk factors for diabetic neuropathy: a case control study

    Directory of Open Access Journals (Sweden)

    Nooraei Mahdi

    2005-12-01

    Full Text Available Abstract Background Diabetes mellitus type II afflicts at least 2 million people in Iran. Neuropathy is one of the most common complications of diabetes and lowers the patient's quality of life. Since neuropathy often leads to ulceration and amputation, we have tried to elucidate the factors that can affect its progression. Methods In this case-control study, 110 diabetic patients were selected from the Shariati Hospital diabetes clinic. Michigan Neuropathic Diabetic Scoring (MNDS was used to differentiate cases from controls. The diagnosis of neuropathy was confirmed by nerve conduction studies (nerve conduction velocity and electromyography. The multiple factors compared between the two groups included consumption of angiotensin converting enzyme inhibitors (ACEI, blood pressure, serum lipid level, sex, smoking, method of diabetes control and its quality. Results Statistically significant relationships were found between neuropathy and age, gender, quality of diabetes control and duration of disease (P values in the order: 0.04, 0.04, Conclusion In this study, hyperglycemia was the only modifiable risk factor for diabetic neuropathy. Glycemic control reduces the incidence of neuropathy, slows its progression and improves the diabetic patient's quality of life. More attention must be paid to elderly male diabetic patients with poor diabetes control with regard to regular foot examinations and more practical education.

  15. Comparative study of control selection in a national population-based case-control study: Estimating risk of smoking on cancer deaths in Chinese men.

    Science.gov (United States)

    Jiang, Jingmei; Liu, Boqi; Nasca, Philip C; Han, Wei; Zou, Xiaonong; Zeng, Xianjia; Tian, Xiaobing; Wu, Yanping; Zhao, Ping; Li, Junyao

    2009-10-28

    To assess the validation of a novel control selection design by comparing the consistency between the new design and a routine design in a large case-control study that was incorporated into a nationwide mortality survey in China. A nationwide mortality study was conducted during 1989-1991. Surviving spouses or other relatives of all adults who died during 1986-1988 provided detailed information about their own as well as the deceased person's smoking history. In this study, 130,079 males who died of various smoking-related cancers at age 35 or over were taken as cases, while 103,248 male surviving spouses (same age range with cases) of women who died during the same period and 49,331 males who died from causes other than those related to smoking were used as control group 1 and control group 2, respectively. Consistency in the results when comparing cases with each of the control groups was assessed. Consistency in the results was observed in the analyses using different control groups although cancer deaths varied with region and age. Equivalence could be ascertained using a 15% criterion in most cancer deaths which had high death rates in urban areas, but they were uncertain for most cancers in rural areas irrespective of whether the hypothesis testing showed significant differences or not. Sex-matched living spouse control design as an alternative control selection for a case-control study is valid and feasible, and the basic principles of the equivalence study are also supported by epidemiological survey data.

  16. Microbial Characteristics of Peri-Implantitis : A Case-Control Study

    NARCIS (Netherlands)

    de Waal, Y C M; Eijsbouts, H V L C; Winkel, E G; van Winkelhoff, A J

    BACKGROUND: Aim of this case-control study was to compare oral microbiological characteristics of subjects with healthy peri-implant conditions and subjects with peri-implantitis and to explore the influence of various patient-related and implant-related factors on the microbiological

  17. Social capital and adverse treatment outcomes of tuberculosis: a case-control study.

    Science.gov (United States)

    Deshmukh, P R; Mundra, A; Dawale, A

    2017-08-01

    'Social capital' refers to social norms, relationships, networks and values that affect the functioning and development of society. Social capital influences health positively, but its role in the treatment outcomes of tuberculosis (TB) is not known. To study the role of social capital in determining adverse TB treatment outcomes. Of 516 patients registered under the Revised National Tuberculosis Control Programme in 2014 in Wardha Tuberculosis Unit, Wardha, India, we included 88 patients with adverse treatment outcomes as cases and 187 controls from among those without adverse outcomes. Multiple logistic regression was used to compare standardised Z-scores. A greater proportion of controls than cases belonged to higher quartiles of social capital and its domains than cases, and the mean standardised Z-score was also consistently higher among controls than cases. Respectively 47% and 15% of cases and controls were in the poorest quartile of social capital, whereas respectively 10% and 33% of cases and controls were in the richest quartile. Each unit increase in Z-score of overall social capital reduced the odds of adverse treatment outcomes by 63.1%. Appropriate interventions for building social capital for TB patients and linking them with the programme would improve programme performance.

  18. Hygiene behaviour and hospitalized severe childhood diarrhoea: a case-control study.

    OpenAIRE

    Baltazar, J. C.; Tiglao, T. V.; Tempongko, S. B.

    1993-01-01

    The relationship between personal and domestic hygiene behaviour and hospitalized childhood diarrhoea was examined in a case-control study of 356 cases and 357 controls from low-income families in metropolitan Manila. Indices of hygiene behaviour were defined for overall cleanliness, kitchen hygiene, and living conditions. Only the indices for overall cleanliness and kitchen hygiene were significantly associated with diarrhoea. An increasing excess risk of hospitalization with severe diarrhoe...

  19. Candidate gene analysis of spontaneous preterm delivery: New insights from re-analysis of a case-control study using case-parent triads and control-mother dyads

    Directory of Open Access Journals (Sweden)

    Myking Solveig

    2011-12-01

    Full Text Available Abstract Background Spontaneous preterm delivery (PTD has a multifactorial etiology with evidence of a genetic contribution to its pathogenesis. A number of candidate gene case-control studies have been performed on spontaneous PTD, but the results have been inconsistent, and do not fully assess the role of how two genotypes can impact outcome. To elucidate this latter point we re-analyzed data from a previously published case-control candidate gene study, using a case-parent triad design and a hybrid design combining case-parent triads and control-mother dyads. These methods offer a robust approach to genetic association studies for PTD compared to traditional case-control designs. Methods The study participants were obtained from the Norwegian Mother and Child Cohort Study (MoBa. A total of 196 case triads and 211 control dyads were selected for the analysis. A case-parent triad design as well as a hybrid design was used to analyze 1,326 SNPs from 159 candidate genes. We compared our results to those from a previous case-control study on the same samples. Haplotypes were analyzed using a sliding window of three SNPs and a pathway analysis was performed to gain biological insight into the pathophysiology of preterm delivery. Results The most consistent significant fetal gene across all analyses was COL5A2. The functionally similar COL5A1 was significant when combining fetal and maternal genotypes. PON1 was significant with analytical approaches for single locus association of fetal genes alone, but was possibly confounded by maternal effects. Focal adhesion (hsa04510, Cell Communication (hsa01430 and ECM receptor interaction (hsa04512 were the most constant significant pathways. Conclusion This study suggests a fetal association of COL5A2 and a combined fetal-maternal association of COL5A1 with spontaneous PTD. In addition, the pathway analysis implied interactions of genes affecting cell communication and extracellular matrix.

  20. Lumbar lordosis and pars interarticularis fractures: a case-control study

    International Nuclear Information System (INIS)

    Bugg, William G.; Lewis, Mark; Juette, Arne; Cahir, John G.; Toms, Andoni P.

    2012-01-01

    The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

  1. Lumbar lordosis and pars interarticularis fractures: a case-control study

    Energy Technology Data Exchange (ETDEWEB)

    Bugg, William G; Lewis, Mark; Juette, Arne; Cahir, John G; Toms, Andoni P [Cotman Centre, Norwich Radiology Academy, Norwich, Norfolk (United Kingdom)

    2012-07-15

    The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

  2. Lumbar lordosis and pars interarticularis fractures: a case-control study

    Energy Technology Data Exchange (ETDEWEB)

    Bugg, William G.; Lewis, Mark; Juette, Arne; Cahir, John G.; Toms, Andoni P. [Cotman Centre, Norwich Radiology Academy, Norwich, Norfolk (United Kingdom)

    2012-07-15

    The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

  3. [Child abuse in Tlaxcala: a case-control study].

    Science.gov (United States)

    Herrada-Huidobro, A; Nazar-Beutelspacher, A; Cassaball-Núñez, M; Vega-Ramos, R; Nava-Cruz, C B

    1992-01-01

    A longitudinal, retrospective and descriptive study about child abuse was carried out in the Hospitals of the Tlaxcala Secretariat of Health, Mexico. The information was obtained from hospitalized children's charts between January first and November 30, 1991. The charts included were those belonging to zero to 14 year old children with injuries, poisoning, and II-III degrees of malnutrition. Four child-abuse criteria were established: physical, sexual, non organic malnutrition and mixed (physical and non organic malnutrition). Two control groups were defined. Different patterns were observed between accidental and non accidental injuries, malnutrition and poisoning among the case and the control groups. The study provides useful information for the integral diagnosis of child abuse in hospitalized children.

  4. Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

    Science.gov (United States)

    Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

    2001-01-01

    Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

  5. Dietary and lifestyle characteristics of colorectal cancer in Jordan: a case-control study.

    Science.gov (United States)

    Arafa, Mostafa A; Waly, Mostafa I; Jriesat, Sahar; Al Khafajei, Ahmed; Sallam, Sunny

    2011-01-01

    We evaluated dietary pattern and lifestyle characteristics of patients with colorectal cancer (CRC) in Jordan. The case-control study included 220 recently diagnosed CRC cases and 220 age and gender matched healthy subjects as a control group. The participating CRC cases had lower dietary intake of fibre, folate, vitamin B12, β-carotene, vitamin C and selenium as compared to controls (P<0.05). The frequency of consumption of fruits and vegetables was also lower among CRC cases, while the frequency of consumption of red meat and saturated fat was higher and positively associated with CRC risk. Furthermore, family history for CRC played a positive role and the majority of CRC cases and controls had a low physical activity level. A sedentary lifestyle and a diet low in fruits and vegetables, and high in animal red meat and saturated fat, appeared associated with CRC among the studied Jordanian subjects. This is consistent with the reported CRC studies in developed nations indicating global causal effects for this tumour type.

  6. Case-control study of mesothelioma in the shipyard industry

    International Nuclear Information System (INIS)

    Correa-Villasenor, A.

    1987-01-01

    A nested case-control study was undertaken to investigate the relationship between occupational exposures to asbestos and low-level gamma radiation and mesothelioma. One hundred nineteen cases and four hundred fifty-two latency-matched controls were selected. Analyses were conducted using the conditional maximum likelihood estimate of the odds ratio and conditional logistic regression for matched sets. The results from the analyses revealed a relationship between asbestos exposure and mesothelioma; the strength of this relationship increased with the intensity and duration of the asbestos exposure. Exposure to low-level gamma radiation was also associated with an increased risk of mesothelioma. There was no interaction between asbestos and radiation. Shipyard employment in non-asbestos jobs and male gender were also found to be associated with mesothelioma

  7. Hygiene behaviour and hospitalized severe childhood diarrhoea: a case-control study.

    Science.gov (United States)

    Baltazar, J C; Tiglao, T V; Tempongko, S B

    1993-01-01

    The relationship between personal and domestic hygiene behaviour and hospitalized childhood diarrhoea was examined in a case-control study of 356 cases and 357 controls from low-income families in metropolitan Manila. Indices of hygiene behaviour were defined for overall cleanliness, kitchen hygiene, and living conditions. Only the indices for overall cleanliness and kitchen hygiene were significantly associated with diarrhoea. An increasing excess risk of hospitalization with severe diarrhoea was noted as the ratings for standards of hygiene became lower, and this excess risk persisted even after controlling for confounding variables. The implications of our findings for the control of diarrhoeal disease are discussed.

  8. Thyroid cancer in French Polynesia: a population based case control study

    International Nuclear Information System (INIS)

    Brindel, P.; Doyon, F.; Adjadj, E.; Vathaire, F. de; Drozdovitch, V.; Bouville, A.; Paoaafaite, J.; Teuri, J.

    2006-01-01

    Full text of publication follows: Because a previous study had shown that registered thyroid cancer incidence is higher among natives of French Polynesia (FP) than in other Maori populations from Hawaii and New-Zealand, a case-control study of thyroid cancer coordinated by Unit 605 of INSERM was conducted in FP. The main objective was to assess the potential role of atmospheric nuclear weapons tests performed by France between 1966 and 1974 on such a high incidence. The study included 600 subjects born and residing in FP: 229 cases of differentiated thyroid carcinoma diagnosed between 1979 and 2004, aged up to 30 years old at start of nuclear weapons testing and 371 control s matched on gender and birth date randomly selected from t he FP registry of births. Face to face interviews were conducted from 2002 to 2004 by specialized investigators native from FP who received a specific formation for this study. Addresses were collected from the territorial medical insurance, which covers all the inhabitants, whatever their professional status. Detailed information about nutrition at time of interview and at the end of adolescence was collected by means of a semi-quantitative method using pictures. Data concerning residence, hormonal and reproductive life, familial and personal background of thyroid pathologies and cancers, and professional and environmental exposure to carcinogens were also collected. For each study subject, radiation thyroid dose was estimated taking into account residential history and dietary habits of the subject and deposition densities of radionuclides reconstructed for each island where the subject resided during the testing period. The iodine intake will be estimated from the dietary questionnaire, as well as from mass-spectrometry measurements of stable iodine in nail clippings, which were collected during the interviews. Among the 229 cases, 89% were females, 54% declared themselves as of pure Maori origin, another 36% of Maori-Asian or Maori

  9. On the Analysis of Case-Control Studies in Cluster-correlated Data Settings.

    Science.gov (United States)

    Haneuse, Sebastien; Rivera-Rodriguez, Claudia

    2018-01-01

    In resource-limited settings, long-term evaluation of national antiretroviral treatment (ART) programs often relies on aggregated data, the analysis of which may be subject to ecological bias. As researchers and policy makers consider evaluating individual-level outcomes such as treatment adherence or mortality, the well-known case-control design is appealing in that it provides efficiency gains over random sampling. In the context that motivates this article, valid estimation and inference requires acknowledging any clustering, although, to our knowledge, no statistical methods have been published for the analysis of case-control data for which the underlying population exhibits clustering. Furthermore, in the specific context of an ongoing collaboration in Malawi, rather than performing case-control sampling across all clinics, case-control sampling within clinics has been suggested as a more practical strategy. To our knowledge, although similar outcome-dependent sampling schemes have been described in the literature, a case-control design specific to correlated data settings is new. In this article, we describe this design, discuss balanced versus unbalanced sampling techniques, and provide a general approach to analyzing case-control studies in cluster-correlated settings based on inverse probability-weighted generalized estimating equations. Inference is based on a robust sandwich estimator with correlation parameters estimated to ensure appropriate accounting of the outcome-dependent sampling scheme. We conduct comprehensive simulations, based in part on real data on a sample of N = 78,155 program registrants in Malawi between 2005 and 2007, to evaluate small-sample operating characteristics and potential trade-offs associated with standard case-control sampling or when case-control sampling is performed within clusters.

  10. Risk Factors Profile of Shoulder Dystocia in Oman: A Case Control Study

    Science.gov (United States)

    Al-Khaduri, Maha M.; Abudraz, Rania Mohammed; Al-Farsi, Yahya M.

    2014-01-01

    Objective This study aimed to assess the risk factor profile of shoulder dystocia and associated neonatal complications in Oman, a developing Arab country. Methods A retrospective case-control study was conducted among 111 cases with dystocia and 111 controls, identified during 1994-2006 period in a tertiary care hospital in Oman. Controls were randomly selected among women who did not have dystocia, and were matched to cases on the day of delivery. Data related to potential risk factors, delivery, and obstetric complications were collected. Results Dystocia was significantly associated with older maternal age, higher parity, larger BMI, diabetes, and previous record of dystocia. In addition, dystocia was associated more with vacuum and forceps deliveries. Routine traction (51%) was the most used manoeuvre. Among dystocia cases, 13% were associated with fetal complications of which Erb’s Palsy was the most prevalent (79%). Conclusion Our finding of significant associations with risk factors lays out the ground to develop a predictability index for shoulder dystocia, which would help in making it preventable. Further p rospective studies are required to confirm the obtained results. PMID:25337307

  11. Risk Factors Profile of Shoulder Dystocia in Oman: A Case Control Study

    Directory of Open Access Journals (Sweden)

    Maha M. Al-Khaduri

    2014-09-01

    Full Text Available Objective: This study aimed to assess the risk factor profile of shoulder dystocia and associated neonatal complications in Oman, a developing Arab country. Methods: A retrospective case-control study was conducted among 111 cases with dystocia and 111 controls, identified during 1994-2006 period in a tertiary care hospital in Oman. Controls were randomly selected among women who did not have dystocia, and were matched to cases on the day of delivery. Data related to potential risk factors, delivery, and obstetric complications were collected. Results: Dystocia was significantly associated with older maternal age, higher parity, larger BMI, diabetes, and previous record of dystocia. In addition, dystocia was associated more with vacuum and forceps deliveries. Routine traction (51% was the most used manoeuvre. Among dystocia cases, 13% were associated with fetal complications of which Erb’s Palsy was the most prevalent (79%. Conclusion: Our finding of significant associations with risk factors lays out the ground to develop a predictability index for shoulder dystocia, which would help in making it preventable. Further prospective studies are required to confirm the obtained results.

  12. Analysis of single nucleotide polymorphisms in case-control studies.

    Science.gov (United States)

    Li, Yonghong; Shiffman, Dov; Oberbauer, Rainer

    2011-01-01

    Single nucleotide polymorphisms (SNPs) are the most common type of genetic variants in the human genome. SNPs are known to modify susceptibility to complex diseases. We describe and discuss methods used to identify SNPs associated with disease in case-control studies. An outline on study population selection, sample collection and genotyping platforms is presented, complemented by SNP selection, data preprocessing and analysis.

  13. The use of the bootstrap in the analysis of case-control studies with missing data

    DEFF Research Database (Denmark)

    Siersma, Volkert Dirk; Johansen, Christoffer

    2004-01-01

    nonparametric bootstrap, bootstrap confidence intervals, missing values, multiple imputation, matched case-control study......nonparametric bootstrap, bootstrap confidence intervals, missing values, multiple imputation, matched case-control study...

  14. Radon and Lung Cancer Case-Control Study in Middle Ural

    International Nuclear Information System (INIS)

    Kirdin, I.A.; Lezhnin, V.L.; Yarmoshenko, I.V.; Ekidin, A.

    2001-01-01

    Full text: The pilot phase of radon and lung cancer case-control study has been performed in Karpinsk and Pervouralsk towns of Middle Ural region of Russia. The case group consists of 341 persons with lung cancer and living in that towns at least five previous years. The lung cancer diagnoses were carefully verified by instrumental techniques and 70% of its were morphologically validated. The persons for the control group (448) were chosen from the population living in that towns at least five years taking into account the age and sex. The special epidemiological questionnaire was developed which includes the items by the groups of factors as follow: clinical data, social factors, chronic lung diseases, life habit, tobacco smoking, alcohol drinking, diet preference etc. The epidemiological questionnaires were fulfilled for each member of case and control groups. Radon gas concentration and thoron equilibrium equivalent concentration measurements had been performed using nuclear track detectors and grab sampling accordingly in the dwellings of case and control groups members. By preliminary estimation the odds ratios are 1, 0.91, 1.2, 1.1 in the ranges of radon and thoron equilibrium equivalent concentration 0-6, 3-13, 13-36 and 36-370 Bq/m 3 respectively. The deeper and more rigorous analysis as well as different independent approaches will be discussed in the paper.(author)

  15. High risk human papillomavirus in the periodontium : A case control study.

    Science.gov (United States)

    Shipilova, Anna; Dayakar, Manjunath Mundoor; Gupta, Dinesh

    2017-01-01

    Human papilloma viruses (HPVs) are small DNA viruses that have been identified in periodontal pocket as well as gingival sulcus. High risk HPVs are also associated with a subset of head and neck carcinomas. It is thought that the periodontium could be a reservoir for HPV. 1. Detection of Human Papilloma virus (HPV) in periodontal pocket as well as gingival of patients having localized chronic periodontitis and gingival sulcus of periodontally healthy subjects. 2. Quantitative estimation of E6 and E7 mRNA in subjects showing presence of HPV3. To assess whether periodontal pocket is a reservoir for HPV. This case-control study included 30 subjects with localized chronic Periodontitis (cases) and 30 periodontally healthy subjects (controls). Two samples were taken from cases, one from periodontal pocket and one from gingival sulcus and one sample was taken from controls. Samples were collected in the form of pocket scrapings and gingival sulcus scrapings from cases and controls respectively. These samples were sent in storage media for identification and estimation of E6/E7 mRNA of HPV using in situ hybridization and flow cytometry. Statistical analysis was done by using, mean, percentage and Chi Square test. A statistical package SPSS version 13.0 was used to analyze the data. P value oral cancer, periodontitis and HPV. However prospective studies are required to further explore this link.

  16. Characteristics and prognosis of pneumococcal endocarditis: a case-control study.

    Science.gov (United States)

    Daudin, M; Tattevin, P; Lelong, B; Flecher, E; Lavoué, S; Piau, C; Ingels, A; Chapron, A; Daubert, J-C; Revest, M

    2016-06-01

    Case series have suggested that pneumococcal endocarditis is a rare disease, mostly reported in patients with co-morbidities but no underlying valve disease, with a rapid progression to heart failure, and high mortality. We performed a case-control study of 28 patients with pneumococcal endocarditis (cases), and 56 patients with non-pneumococcal endocarditis (controls), not matched for sex and age, during the years 1991-2013, in one referral centre. Alcoholism (39.3% versus 10.7%; p endocarditis. Cardiac surgery was required in 64.3% of patients with pneumococcal endocarditis, much earlier than in patients with non-pneumococcal endocarditis (mean time from symptom onset, 14.1 ± 18.2 versus 69.0 ± 61.1 days). In-hospital mortality rates were similar (7.1% versus 12.5%). Streptococcus pneumoniae causes rapidly progressive endocarditis requiring life-saving early cardiac surgery in most cases. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  17. Putative periodontopathic bacteria and herpesviruses in pregnant women: a case-control study

    OpenAIRE

    Lu, Haixia; Zhu, Ce; Li, Fei; Xu, Wei; Tao, Danying; Feng, Xiping

    2016-01-01

    Little is known about herpesvirus and putative periodontopathic bacteria in maternal chronic periodontitis. The present case-control study aimed to explore the potential relationship between putative periodontopathic bacteria and herpesviruses in maternal chronic periodontitis.Saliva samples were collected from 36 pregnant women with chronic periodontitis (cases) and 36 pregnant women with healthy periodontal status (controls). Six putative periodontopathic bacteria (Porphyromonas gingivalis ...

  18. Waterparks are high risk for cryptosporidiosis: A case-control study in Victoria, 2015.

    Science.gov (United States)

    de Gooyer, Tanyth E; Gregory, Joy; Easton, Marion; Stephens, Nicola; Fearnley, Emily; Kirk, Martyn

    2017-06-30

    An increase in notifications of cryptosporidiosis was observed in Victoria between March and April 2015. Cases mostly resided in one metropolitan region and hypothesis-generating interviews identified common exposures to aquatic facilities. We conducted a case-control study to determine exposure source(s) and facilitate control measures. Laboratory-confirmed cases of cryptosporidiosis from the region of interest notified between 1 March and 23 April 2015 were included. Controls residing in the same region were recruited from participants in a population health survey and frequency matched (2 per case) by age group. Details of exposure to potential risk factors were collected using a standardised telephone questionnaire for the 14-days prior to illness for cases, and an analogous exposure period for controls. Univariable and multivariable logistic regression were used to determine risk factors associated with illness using STATA SE 13.1. Thirty cases and 66 controls were included in the study. Half the cases were less than 12 years of age and 62% were female. Illness was most strongly associated with recreational water exposure at any waterpark (adjusted odds ratio (aOR)=73.5; 95% confidence interval (CI):6.74-802), and specifically at Victorian waterparks (aOR=45.6; 95% CI:5.20-399). Cases were linked with attendance at either a waterpark in the region or an adjacent region. As a result of this investigation, hyperchlorination was completed at identified facilities and swim hygiene information distributed. This study reinforces the potential for recreational water facilities, particularly waterparks, to act as a transmission source of Cryptosporidium infections. Continued communication to patrons is required to ensure healthy swimming practice in Victorian aquatic facilities.

  19. Adaptation of Chain Event Graphs for use with Case-Control Studies in Epidemiology.

    Science.gov (United States)

    Keeble, Claire; Thwaites, Peter Adam; Barber, Stuart; Law, Graham Richard; Baxter, Paul David

    2017-09-26

    Case-control studies are used in epidemiology to try to uncover the causes of diseases, but are a retrospective study design known to suffer from non-participation and recall bias, which may explain their decreased popularity in recent years. Traditional analyses report usually only the odds ratio for given exposures and the binary disease status. Chain event graphs are a graphical representation of a statistical model derived from event trees which have been developed in artificial intelligence and statistics, and only recently introduced to the epidemiology literature. They are a modern Bayesian technique which enable prior knowledge to be incorporated into the data analysis using the agglomerative hierarchical clustering algorithm, used to form a suitable chain event graph. Additionally, they can account for missing data and be used to explore missingness mechanisms. Here we adapt the chain event graph framework to suit scenarios often encountered in case-control studies, to strengthen this study design which is time and financially efficient. We demonstrate eight adaptations to the graphs, which consist of two suitable for full case-control study analysis, four which can be used in interim analyses to explore biases, and two which aim to improve the ease and accuracy of analyses. The adaptations are illustrated with complete, reproducible, fully-interpreted examples, including the event tree and chain event graph. Chain event graphs are used here for the first time to summarise non-participation, data collection techniques, data reliability, and disease severity in case-control studies. We demonstrate how these features of a case-control study can be incorporated into the analysis to provide further insight, which can help to identify potential biases and lead to more accurate study results.

  20. Mental illness, poverty and stigma in India: a case-control study.

    Science.gov (United States)

    Trani, Jean-Francois; Bakhshi, Parul; Kuhlberg, Jill; Narayanan, Sreelatha S; Venkataraman, Hemalatha; Mishra, Nagendra N; Groce, Nora E; Jadhav, Sushrut; Deshpande, Smita

    2015-02-23

    To assess the effect of experienced stigma on depth of multidimensional poverty of persons with severe mental illness (PSMI) in Delhi, India, controlling for gender, age and caste. Matching case (hospital)-control (population) study. University Hospital (cases) and National Capital Region (controls), India. A case-control study was conducted from November 2011 to June 2012. 647 cases diagnosed with schizophrenia or affective disorders were recruited and 647 individuals of same age, sex and location of residence were matched as controls at a ratio of 1:2:1. Individuals who refused consent or provided incomplete interview were excluded. Higher risk of poverty due to stigma among PSMI. 38.5% of PSMI compared with 22.2% of controls were found poor on six dimensions or more. The difference in multidimensional poverty index was 69% between groups with employment and income of the main contributors. Multidimensional poverty was strongly associated with stigma (OR 2.60, 95% CI 1.27 to 5.31), scheduled castes/scheduled tribes/other backward castes (2.39, 1.39 to 4.08), mental illness (2.07, 1.25 to 3.41) and female gender (1.87, 1.36 to 2.58). A significant interaction between stigma, mental illness and gender or caste indicates female PSMI or PSMI from 'lower castes' were more likely to be poor due to stigma than male controls (ppoverty linked to SMI are pervasive and intertwined. In particular for low caste and women, it is a strong predictor of poverty. Exclusion from employment linked to negative attitudes and lack of income are the highest contributors to multidimensional poverty, increasing the burden for the family. Mental health professionals need to be aware of and address these issues. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Importance of Internal Audit and Internal Control in an organization - Case Study

    OpenAIRE

    Bubilek, Olga

    2017-01-01

    This research is a descriptive case study of a company. It presents concepts of the internal audit and internal control based on an example of a Finnish company. The research examines the role and importance that internal audit and internal controls have in an organization. The main research question is “What is the role and importance of internal audit and internal control in an organization” Additional sub-questions relating to the case company that will allow for better understanding of...

  2. Nutritional variables and work-related accidents: a case-control study.

    Science.gov (United States)

    de Medeiros, M A T; Zangirolani, Lia Thieme Oikawa; Cordeiro, Ricardo Carlos; da Costa, Proença Rossana Pacheco; Diez-Garcia, Rosa Wanda

    2014-01-01

    Nutritional aspects are important for the prevention of diseases and disorders, and few studies have focused on the relationship between risk of work injury and nutritional variables. This study aimed to verify whether nutritional variables constitute risk factors for work-related accidents. 1,422 industrial workers (600 cases plus 822 controls). A case-control study was carried out in an industrial city in south-east Brazil. A multiple logistic regression model was adjusted using work-related accidents as the response variable and nutritional variables as predictors. The associations were assessed by Odds Ratio (OR), with a p-value work-related accidents were (a) attending formal education for an above average number of years (OR=0.91, pwork-related accidents. This indicates the need, during the formulation of policies for these kinds of government benefits, to include nutrition aspects in order to minimize work-related accidents risks.

  3. Comparison of two control groups for estimation of oral cholera vaccine effectiveness using a case-control study design.

    Science.gov (United States)

    Franke, Molly F; Jerome, J Gregory; Matias, Wilfredo R; Ternier, Ralph; Hilaire, Isabelle J; Harris, Jason B; Ivers, Louise C

    2017-10-13

    Case-control studies to quantify oral cholera vaccine effectiveness (VE) often rely on neighbors without diarrhea as community controls. Test-negative controls can be easily recruited and may minimize bias due to differential health-seeking behavior and recall. We compared VE estimates derived from community and test-negative controls and conducted bias-indicator analyses to assess potential bias with community controls. From October 2012 through November 2016, patients with acute watery diarrhea were recruited from cholera treatment centers in rural Haiti. Cholera cases had a positive stool culture. Non-cholera diarrhea cases (test-negative controls and non-cholera diarrhea cases for bias-indicator analyses) had a negative culture and rapid test. Up to four community controls were matched to diarrhea cases by age group, time, and neighborhood. Primary analyses included 181 cholera cases, 157 non-cholera diarrhea cases, 716 VE community controls and 625 bias-indicator community controls. VE for self-reported vaccination with two doses was consistent across the two control groups, with statistically significant VE estimates ranging from 72 to 74%. Sensitivity analyses revealed similar, though somewhat attenuated estimates for self-reported two dose VE. Bias-indicator estimates were consistently less than one, with VE estimates ranging from 19 to 43%, some of which were statistically significant. OCV estimates from case-control analyses using community and test-negative controls were similar. While bias-indicator analyses suggested possible over-estimation of VE estimates using community controls, test-negative analyses suggested this bias, if present, was minimal. Test-negative controls can be a valid low-cost and time-efficient alternative to community controls for OCV effectiveness estimation and may be especially relevant in emergency situations. Copyright © 2017. Published by Elsevier Ltd.

  4. High risk human papillomavirus in the periodontium : A case control study

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    Anna Shipilova

    2017-01-01

    Full Text Available Background: Human papilloma viruses (HPVs are small DNA viruses that have been identified in periodontal pocket as well as gingival sulcus. High risk HPVs are also associated with a subset of head and neck carcinomas. It is thought that the periodontium could be a reservoir for HPV. Aims: 1. Detection of Human Papilloma virus (HPV in periodontal pocket as well as gingival of patients having localized chronic periodontitis and gingival sulcus of periodontally healthy subjects. 2. Quantitative estimation of E6 and E7 mRNA in subjects showing presence of HPV3. To assess whether periodontal pocket is a reservoir for HPV. Settings and Design: This case-control study included 30 subjects with localized chronic Periodontitis (cases and 30 periodontally healthy subjects (controls. Two samples were taken from cases, one from periodontal pocket and one from gingival sulcus and one sample was taken from controls. Methods and Materials: Samples were collected in the form of pocket scrapings and gingival sulcus scrapings from cases and controls respectively. These samples were sent in storage media for identification and estimation of E6/E7 mRNA of HPV using in situ hybridization and flow cytometry. Statistical analysis: Statistical analysis was done by using, mean, percentage and Chi Square test. A statistical package SPSS version 13.0 was used to analyze the data. P value < 0.05 was considered as statistically significant. Results: pocket samples as well as sulcus samples for both cases and controls were found to contain HPV E6/E7 mRNAInterpretation and Conclusion: Presence of HPV E6/E7 mRNA in periodontium supports the hypothesis that periodontal tissues serve as a reservoir for latent HPV and there may be a synergy between oral cancer, periodontitis and HPV. However prospective studies are required to further explore this link.

  5. Psychiatric morbidity in psoriasis: A case-control study

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    Sunil Goyal

    2017-01-01

    Full Text Available Objective: Psoriasis is a chronic, relapsing and disfiguring dermatological disorder with a significant effect on occupational, social, and other areas of functioning. Psychological stress has been known to have a significant role in the onset and exacerbation of this illness. To study the prevalence of psychiatric morbidity in psoriasis and the influence of specified demographic, psychological, social and illness-related variables. Methods: The study was carried out at a tertiary care hospital in a large urban setup. In this case–control study, 100 cases of psoriasis were studied in comparison with healthy controls who were matched for sociodemographic profile. The participants were given a sociodemographic questionnaire, clinical profile sheet, and psoriasis area and severity index (PASI. General Health Questionnaire-12 (GHQ-12 was used to screen for psychological distress, and subsequently, Hospital Anxiety and Depression Scale for screening for depression and anxiety and World Health Organization Quality of Life-BREF scale for assessing the quality of life (QOL were administered. The results obtained were analyzed for evaluating the psychiatric morbidity and its various correlates. Appropriate statistical analysis was done using SPSS 21. Results: Using GHQ-12 cutoff score (≥3 for psychological distress, the overall prevalence of psychological distress was significantly more in cases of in comparison to healthy controls with an odds ratio of 8.54 (95% confidence interval 3.16–23.07, P < 0.0001. Statistical analysis showed a statistically significant correlation of educational status with QOL and severity of skin lesions (PASI with anxiety level. Severe skin lesions, more so on visible body parts were associated more commonly with psychological distress. Conclusions: All patients of psoriasis should be educated about the nature of the illness and screened for psychological distress. Dermatologists and family members should be educated to

  6. Selection of controls in case-control studies on maternal medication use and risk of birth defects

    NARCIS (Netherlands)

    Bakker, M.K.; de Walle, H.E.; Dequito, A.; van den Berg, P.B.; de Jong-van den Berg, L.T.

    BACKGROUND:: In case-control studies on teratogenic risks of maternal drug use during pregnancy, the use of normal or malformed controls may lead to recall-bias or selection bias. This can be avoided by using controls with a genetic disorder. However, researchers are hesitant to use these as

  7. Risk factors for cataract: A case control study

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    Ughade Suresh

    1998-01-01

    Full Text Available The present study was designed as a hospital-based, group-matched, case-control investigation into the risk factors associated with age-related cataract in central India. The study included 262 cases of age-related cataract and an equal number of controls. A total of 21 risk factors were evaluated: namely, low socioeconomic status (SES, illiteracy, marital status, history of diarrhoea, history of diabetes, glaucoma, use of cholinesterase inhibitors, steroids, spironolactone, nifedipine, analgesics, myopia early in life, renal failure, heavy smoking, heavy alcohol consumption, hypertension, low body mass index (BMI, use of cheaper cooking fuel, working in direct sunlight, family history of cataract, and occupational exposure. In univariate analysis, except marital status, low BMI, renal failure, use of steroids, spironolactone, analgesics, and occupational exposure, all 14 other risk factors were found significantly associated with age-related cataract. Unconditional multiple logistic regression analysis confirmed the significance of low SES, illiteracy, history of diarrhoea, diabetes, glaucoma, myopia, smoking, hypertension and cheap cooking fuel. The etiological role of these risk factors in the outcome of cataract is confirmed by the estimates of attributable risk proportion. The estimates of population attributable risk proportion for these factors highlight the impact of elimination of these risk factors on the reduction of cataract in this population.

  8. Co-Prevalence of Tremor with Spasmodic Dysphonia: A Case-Control Study

    Science.gov (United States)

    White, Laura; Klein, Adam; Hapner, Edie; Delgaudio, John; Hanfelt, John; Jinnah, H. A.; Johns, Michael

    2011-01-01

    OBJECTIVES/HYPOTHESIS The aim of this study was to define the co-prevalence of tremor with spasmodic dysphonia (SD). STUDY DESIGN A single institution prospective, case-control study was performed from May 2010 to July 2010. METHODS Consecutive patients with SD (cases) and other voice disorders (controls) were enrolled prospectively. Each participant underwent a voice evaluation and an evaluation for tremor. RESULTS 146 voice disorder controls and 128 patients with SD were enrolled. 26% of patients with SD had vocal tremor, 21% had non-vocal tremor. Patients with SD were 2.8 times more likely to have co-prevalent tremor than the control group (OR = 2.81; 95% CI, 1.55 to 5.08) and only 35% of patients with SD had been seen by a neurologist for the evaluation of dystonia and tremor. CONCLUSIONS Tremor is highly prevalent in patients with SD. It is important for each patient diagnosed with SD to undergo an evaluation for tremor, this is especially important in patients diagnosed with vocal tremor. Level of evidence 3b. PMID:21792965

  9. Can iridology detect susceptibility to cancer? A prospective case-controlled study.

    Science.gov (United States)

    Münstedt, Karsten; El-Safadi, Samer; Brück, Friedel; Zygmunt, Marek; Hackethal, Andreas; Tinneberg, Hans-Rudolf

    2005-06-01

    This prospective case-control study aimed to investigate the value of iridology as a diagnostic tool in detecting some common cancers. One hundred ten (110) subjects were enrolled in the study: 68 subjects had histologically proven cancers of the breast, ovary, uterus, prostate, or colorectum, and 42 were control subjects. All subjects were examined by an experienced practitioner of iridology, who was unaware of their gender or medical details. He was allowed to suggest up to five diagnoses for each subject and his results were then compared with each subject's medical diagnosis to determine the accuracy of iridology in detecting malignancy. Iridology identified the correct diagnosis in only 3 cases (sensitivity, 0.04). Iridology was of no value in diagnosing the cancers investigated in this study.

  10. Modified metabolic syndrome and second cancers in women: A case control study.

    Science.gov (United States)

    Ortiz-Mendoza, Carlos-Manuel; Pérez-Chávez, Ernesto; Fuente-Vera, Tania-Angélica De-la

    2016-01-01

    According to some studies, the metabolic syndrome causes diverse primary cancers; however, there is no evidence about metabolic syndrome impact on second cancers development in women. To find out the implication of the modified metabolic syndrome in women with second cancers. This was a case-control study, at a general hospital in Mexico City, in women with second cancers (cases) and age-matched women with only one neoplasm (controls). The analysis comprised: Tumor (s), anthropometric features, and body mass index (BMI); moreover, presence of diabetes mellitus, hypertension, and fasting serum levels of total cholesterol, triglycerides and glucose. The sample was of nine cases and 27 controls. In cases, the metabolic syndrome (diabetes mellitus or glucose > 99 mg/dL + hypertension or blood pressure ≥ 135/85 mm Hg + triglycerides > 149 mg/dL or BMI ≥ 30 kg/m 2 ) was more frequent (odds ratio 20.8, 95% confidence interval: 1.9-227.1). Our results suggest that in women, the modified metabolic syndrome may be a risk factor for second cancers.

  11. Modified metabolic syndrome and second cancers in women: A case control study

    Directory of Open Access Journals (Sweden)

    Carlos-Manuel Ortiz-Mendoza

    2016-01-01

    Full Text Available Background: According to some studies, the metabolic syndrome causes diverse primary cancers; however, there is no evidence about metabolic syndrome impact on second cancers development in women. Aim: To find out the implication of the modified metabolic syndrome in women with second cancers. Materials and Methods: This was a case-control study, at a general hospital in Mexico City, in women with second cancers (cases and age-matched women with only one neoplasm (controls. The analysis comprised: Tumor (s, anthropometric features, and body mass index (BMI; moreover, presence of diabetes mellitus, hypertension, and fasting serum levels of total cholesterol, triglycerides and glucose. Results: The sample was of nine cases and 27 controls. In cases, the metabolic syndrome (diabetes mellitus or glucose > 99 mg/dL + hypertension or blood pressure ≥ 135/85 mm Hg + triglycerides > 149 mg/dL or BMI ≥ 30 kg/m 2 was more frequent (odds ratio 20.8, 95% confidence interval: 1.9-227.1. Conclusion: Our results suggest that in women, the modified metabolic syndrome may be a risk factor for second cancers.

  12. Adipokines as Possible New Predictors of Cardiovascular Diseases: A Case Control Study

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    Laura Pala

    2012-01-01

    Full Text Available Background and Aims. The secretion of several adipocytokines, such as adiponectin, retinol-binding protein 4 (RBP4, adipocyte fatty acid binding protein (aFABP, and visfatin, is altered in subjects with abdominal adiposity; these endocrine alterations could contribute to increased cardiovascular risk. The aim of the study was to assess the relationship among adiponectin, RBP4, aFABP, and visfatin, and incident cardiovascular disease. Methods and Results. A case-control study, nested within a prospective cohort, on 2945 subjects enrolled for a diabetes screening program was performed. We studied 18 patients with incident fatal or nonfatal IHD (Ischemic Heart Disease or CVD (Cerebrovascular Disease, compared with 18 matched control subjects. Circulating adiponectin levels were significantly lower in cases of IHD with respect to controls. Circulating RBP4 levels were significantly increased in CVD and decreased in IHD with respect to controls. Circulating aFABP4 levels were significantly increased in CVD, while no difference was associated with IHD. Circulating visfatin levels were significantly lower in cases of both CVD and IHD with respect to controls, while no difference was associated with CVD. Conclusions. The present study confirms that low adiponectin is associated with increased incidents of IHD, but not CVD, and suggests, for the first time, a major effect of visfatin, aFABP, and RBP4 in the development of cardiovascular disease.

  13. Identifying risk factors for blindness from primary open-angle glaucoma by race: a case-control study.

    Science.gov (United States)

    Williams, Andrew M; Huang, Wei; Muir, Kelly W; Stinnett, Sandra S; Stone, Jordan S; Rosdahl, Jullia A

    2018-01-01

    To examine the factors associated with blindness from primary open-angle glaucoma (POAG) among black and white patients at our institution. For this retrospective, case-control study, patients legally blind from POAG ("cases") were matched on age, race, and gender with non-blind POAG patients ("controls"). Thirty-seven black case-control pairs and 19 white case-control pairs were included in this study. Clinical variables were compared at initial presentation and over the course of follow-up. Black case-control pairs and white case-control pairs had similar characteristics at presentation, including cup-to-disc ratio and number of glaucoma medications. However, over the course of follow-up, black cases underwent significantly more glaucoma surgeries than matched controls (2.4 versus 1.2, p =0.001), whereas white cases and controls had no significant difference in glaucoma operations (0.9 versus 0.6, p =0.139). Our analysis found that glaucoma surgery is associated with blindness in black patients (odds ratio [OR] 1.6, 95% CI 1.1-2.2) but not in white patients (OR 1.5, 95% CI 0.7-3.2). Black and white case-control pairs with POAG shared similar risk factors for blindness at presentation. However, over the follow-up period, black cases required significantly more glaucoma surgeries compared to black controls, whereas there was no significant difference in surgery between white cases and controls. There was no difference in medication changes in either case-control set.

  14. An Epidemiological Study of Accidents in a Construction Industry: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Malakouti J.

    2013-01-01

    Full Text Available Background and Objectives: Despite science and technology development and their application in various industries, accidents continue to occur in many workplaces. This study was designed and carried out with the aim of epidemiological survey of accident among workers of a tunneling industry.Methods: This study was conducted on 144 out of a total of 440 employees of a tunneling project who were at risk of occupational accidents. 48 workers with a history of occupational accident over the past two years were selected as case group and 96 workers of the same project were selected as control group. The data were collected through a designed checklist and analyzed using logistic regression, chi-square and independent t tests.Results: A significant association was observed between accident rate and different age groups (p<0.05. There was a significant relationship (p=0.016 in the case of sport activities between case and control groups, and significant relationships were observed between two groups regarding education (p=0.057 and smoking (p=0.06, but there was no significant relationships between accident occurrence with marital status, residence in workplace, job related education, job experience, chronic diseases and obesity.Conclusion: The results of this study clarify the necessity of the use of epidemiological data in preventive and control measures in workplaces. Therefore, Developing programs for determination of physical and mental capacity of workers are essential to employ them in jobs commensurate with their abilities, especially in older workers.

  15. A case-control study of Yersinia enterocolitica infections in Auckland.

    Science.gov (United States)

    Satterthwaite, P; Pritchard, K; Floyd, D; Law, B

    1999-10-01

    To identify major risk factors for Yersinia enterocolitica (YE) and identify measures to reduce YE infections. A prospective case control study, group age matched, using 186 cases of YE identified by community pathology laboratories and 379 randomly selected controls. Conducted between April 1995 and June 1996 in Auckland, New Zealand. Face-to-face interviews used a standardised questionnaire examining exposures to factors potentially associated with YE infections including untreated water, unreticulated sewerage, consumption of selected foods, selected food handling practices and socio-demographic factors. Multivariate logistic regression was used to calculate adjusted odds ratios for the potential risk factors. Population attributable risk (PAR) was calculated for significant exposures. Having more than two people living in the home was more common among cases than controls (OR = 2.2). Town supply water (OR = 0.2), reticulated sewerage (OR = 0.34) and looking after a young child (OR = 0.51) were significantly less common. Of the meats, only pork (OR = 1.34) had a higher consumption rate, while bacon (OR = 0.75) and smallgoods (OR = 0.73) were consumed less frequently by cases than controls. Eating food from a sandwich bar was more frequent among cases (OR = 1.18). Fruit and vegetable consumption was marginally less (OR = 0.98). The population attributable risk of these factors was 0.89, implying that 89% of YE would be eliminated if adverse exposures were removed. The risk of YE illness is increased by contact with untreated water, unreticulated sewerage and consumption of pork. Investigation of non-town water supply, informal sewerage systems and methods of preparation and consumption of pork are recommended to determine how YE enters the human food chain.

  16. Externalizing behavior and impulsivity in the children of alcoholics: A case-control study

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    Ayyanar Sugaparaneetharan

    2016-01-01

    Full Text Available Context: Reduced behavioural inhibition, characterized by impulsivity and disruptive behaviour disorders, has been identified as a developmental precursor of alcoholism with a considerable genetic component. Aims: The present study aimed to assess whether children of fathers with alcohol dependence have high impulsivity and externalizing behaviours. Setting and Design: Observational case-control study, done in a tertiary care teaching hospital of Southern India. Materials and Methods: The present case-control study recruited 50 children aged 7 to 14 years of fathers with alcohol dependence and 50 age- and gender-matched children of fathers without alcohol dependence. The two groups were compared using the DSM-IV-TR criteria for ADHD, the Barratt Impulsivity Scale (BIS and the Child Behaviour Checklist (CBCL. Statistical Analysis Used: Descriptive statistics used to summarise the study findings. Cases and controls were compared on BIS and CBCL scores using a general linear model (GLM. All analyses were two tailed and test P value <0.05 was considered significant. Results: The children of fathers with alcohol dependence were more likely to meet criteria for ADHD (30% versus 10%, χ2 = 6.250, P = 0.012. After controlling for age and gender, impulsivity scores on the BIS tended to be higher in the cases (F = 2.410, P = 0.055 than controls, mainly in the non-planning domains (F = 3.650, P = 0.008. Similarly, externalizing behaviours on CBCL were more common in the cases than controls (F = 2.817, P = 0.029. Conclusions: Children of fathers with alcohol dependence had greater impulsivity and externalizing behaviours. This may represent a behavioural phenotype as well as a potential target for early intervention.

  17. A case-control study of airways obstruction among construction workers.

    Science.gov (United States)

    Dement, John; Welch, Laura; Ringen, Knut; Quinn, Patricia; Chen, Anna; Haas, Scott

    2015-10-01

    While smoking is the major cause of chronic obstructive pulmonary disease (COPD), occupational exposures to vapors, gases, dusts, and fumes (VGDF) increase COPD risk. This case-control study estimated the risk of COPD attributable to occupational exposures among construction workers. The study population included 834 cases and 1243 controls participating in a national medical screening program for older construction workers between 1997 and 2013. Qualitative exposure indices were developed based on lifetime work and exposure histories. Approximately 18% (95% CI = 2-24%) of COPD risk can be attributed to construction-related exposures, which are additive to the risk contributed by smoking. A measure of all VGDF exposures combined was a strong predictor of COPD risk. Construction workers are at increased risk of COPD as a result of broad and complex effects of many exposures acting independently or interactively. Control methods should be implemented to prevent worker exposures, and smoking cessation should be promoted. © 2015 The Authors. American Journal of Industrial Medicine Published by Wiley Periodicals, Inc.

  18. Clinical implications of antiretroviral drug interactions with warfarin: a case-control study.

    Science.gov (United States)

    Esterly, John S; Darin, Kristin M; Gerzenshtein, Lana; Othman, Fidah; Postelnick, Michael J; Scarsi, Kimberly K

    2013-06-01

    Warfarin, a frequently prescribed anticoagulant with a narrow therapeutic index, is susceptible to drug-drug interactions with antiretroviral therapy (ART). This study compared the warfarin maintenance dose (WMD) between patients receiving and not receiving ART and evaluated predictors of warfarin dosage among those on ART. This was a case-control (1:2) study. Cases were HIV-infected patients receiving warfarin and protease inhibitor (PI)- and/or non-nucleoside reverse transcriptase inhibitor (NNRTI)-based ART. Controls were randomly selected HIV-uninfected patients receiving warfarin. The WMD was compared between cases and controls and between cases on varying ART regimens. Bivariate comparisons were performed and a linear regression model was developed to identify predictors of WMD. We identified 18 case and 36 control patients eligible for inclusion. Cases were younger than controls (mean age: 45.8 versus 63.1 years, P African American (50.0% versus 22.2%, P=0.04). ART was classified as PI-based (n=9), NNRTI-based (n=7) and PI + NNRTI-based (n=2). The WMD (mean ± SD) differed between cases and controls (8.6  ±  3.4 mg versus 5.1 ± 1.5 mg, P ART regimens (PI: 8.8  ±  4.5 mg; NNRTI: 8.6   ± 1.8 mg; PI + NNRTI: 7.3  ±  3.3 mg; P = 0.86). Race and ritonavir dose were independent predictors of WMD, predicting an increase of 3.9 mg (95% CI: 0.88-6.98, P = 0.02) if a patient was African American or 3.7 mg (95% CI: 0.53-6.89, P = 0.03) if the total daily ritonavir dose was 200 mg. The required WMD was significantly higher in patients receiving ART. Prompt dose titration to achieve a higher WMD with vigilant monitoring may be required due to these drug-drug interactions.

  19. On estimation of time-dependent attributable fraction from population-based case-control studies.

    Science.gov (United States)

    Zhao, Wei; Chen, Ying Qing; Hsu, Li

    2017-09-01

    Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

  20. Sexual Dysfunction in Breast Cancer: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Mandana Ebrahimi

    2015-02-01

    Full Text Available Background: Sexual dysfunction in breast cancer patients is considered as a common and distressing problem. Considering the increasing number of breast cancer survivors living for longer periods of time with the disease and the importance of their quality of life, we conducted the present study to compare the sexual functioning in breast cancer patients with their healthy counterparts.Methods: In this case-control study, breast cancer patients who completed their treatment protocol and were followed up for at least six months were included. The controls were healthy women with normal clinical breast examinations. All subjects filled-in the Persian version of Female Sexual Function Index questionnaire.Results: A total of 165 subjects including 71 breast cancer patients and 94 healthy women were studied. The frequency of sexual dysfunction in cases and controls was 52.6% and 47.4%, respectively (P = 0.09. There were no significant differences between the two groups regarding domain scores, except for vaginal lubrication (P = 0.045. Logistic regression analysis indicated that significant determinants of sexual dysfunction in breast cancer group was patients' age (OR = 4.0, 95%CI: 1.3 – 11.5, P = 0.01 and age of the spouse (OR= 9.8, 95% CI: 1.8-51.9, P= 0.007, while in controls, only emotional relationship with the husband was the significant predictive factor (OR = 6.3, 95%CI: 1.9 – 20.5, P = 0.002.Conclusions: Our findings indicated that sexual dysfunction is prevalent in Iranian women regardless of their physical health status. The frequency of vaginal dryness in breast cancer patients was significantly higher than controls. Age of the patient and the spouse (>40 were the only significant predictors of sexual dysfunction among women with breast cancer. Preventive strategies, sexual education and access to effective treatment should be planned in supportive care of breast cancer patients.

  1. Effect of alpha amylase on early childhood caries: a matched case-control study

    OpenAIRE

    Mojarad, Farzad; Department of Pediatric Dentistry, School of Dentistry, Hamadan University of Medical Sciences, Hamadan; Fazlollahifar, Samira; Department of Pediatric Dentistry, School of Dentistry, Hamadan University of Medical Sciences, Hamadan; Poorolajal, Jalal; Research Center for Health Sciences, Department of Epidemiology & Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan; Hajilooi, Mehrdad; Department of Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan

    2013-01-01

    Objectives: There are a few studies addressing the relationship between salivary alpha-amylase and dental caries. This study was implemented in order to investigate the effect of salivary alpha-amylase level on early childhood caries (ECC).Materials and Methods: In this matched case-control study, which was carried out from November 2011 to March 2012 in Hamadan City, the west of Iran, mean levels of salivary alpha-amylase of 84 ECC-active cases were compared to that of 84 ECC-free controls u...

  2. Environmental and occupational risk factors for progressive supranuclear palsy: Case-control study.

    Science.gov (United States)

    Litvan, Irene; Lees, Peter S J; Cunningham, Christopher R; Rai, Shesh N; Cambon, Alexander C; Standaert, David G; Marras, Connie; Juncos, Jorge; Riley, David; Reich, Stephen; Hall, Deborah; Kluger, Benzi; Bordelon, Yvette; Shprecher, David R

    2016-05-01

    The cause of progressive supranuclear palsy (PSP) is largely unknown. Based on evidence for impaired mitochondrial activity in PSP, we hypothesized that the disease may be related to exposure to environmental toxins, some of which are mitochondrial inhibitors. This multicenter case-control study included 284 incident PSP cases of 350 cases and 284 age-, sex-, and race-matched controls primarily from the same geographical areas. All subjects were administered standardized interviews to obtain data on demographics, residential history, and lifetime occupational history. An industrial hygienist and a toxicologist unaware of case status assessed occupational histories to estimate past exposure to metals, pesticides, organic solvents, and other chemicals. Cases and controls were similar on demographic factors. In unadjusted analyses, PSP was associated with lower education, lower income, more smoking pack-years, more years of drinking well water, more years living on a farm, more years living 1 mile from an agricultural region, more transportation jobs, and more jobs with exposure to metals in general. However, in adjusted models, only more years of drinking well water was significantly associated with PSP. There was an inverse association with having a college degree. We did not find evidence for a specific causative chemical exposure; higher number of years of drinking well water is a risk factor for PSP. This result remained significant after adjusting for income, smoking, education and occupational exposures. This is the first case-control study to demonstrate PSP is associated with environmental factors. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

  3. Individual Correlates of Podoconiosis in Areas of Varying Endemicity: A Case-Control Study

    Science.gov (United States)

    Molla, Yordanos B.; Le Blond, Jennifer S.; Wardrop, Nicola; Baxter, Peter; Atkinson, Peter M.; Newport, Melanie J.; Davey, Gail

    2013-01-01

    Background Podoconiosis is a non-filarial form of elephantiasis resulting in lymphedema of the lower legs. Previous studies have suggested that podoconiosis arises from the interplay of individual and environmental factors. Here, our aim was to understand the individual-level correlates of podoconiosis by comparing 460 podoconiosis-affected individuals and 707 unaffected controls. Methods/principal findings This was a case-control study carried out in six kebeles (the lowest governmental administrative unit) in northern Ethiopia. Each kebele was classified into one of three endemicity levels: ‘low’ (prevalence 5%). A total of 142 (30.7%) households had two or more cases of podoconiosis. Compared to controls, the majority of the cases, especially women, were less educated (OR = 1.7, 95% CI = 1.3 to 2.2), were unmarried (OR = 3.4, 95% CI = 2.6–4.6) and had lower income (t = −4.4, p<0.0001). On average, cases started wearing shoes ten years later than controls. Among cases, age of first wearing shoes was positively correlated with age of onset of podoconiosis (r = 0.6, t = 12.5, p<0.0001). Among all study participants average duration of shoe wearing was less than 30 years. Between both cases and controls, people in ‘high’ and ‘medium’ endemicity kebeles were less likely than people in ‘low’ endemicity areas to ‘ever’ have owned shoes (OR = 0.5, 95% CI = 0.4–0.7). Conclusions Late use of shoes, usually after the onset of podoconiosis, and inequalities in education, income and marriage were found among cases, particularly among females. There were clustering of cases within households, thus interventions against podoconiosis will benefit from household-targeted case tracing. Most importantly, we identified a secular increase in shoe-wearing over recent years, which may give opportunities to promote shoe-wearing without increasing stigma among those at high risk of podoconiosis. PMID:24340109

  4. Individual correlates of podoconiosis in areas of varying endemicity: a case-control study.

    Directory of Open Access Journals (Sweden)

    Yordanos B Molla

    Full Text Available Podoconiosis is a non-filarial form of elephantiasis resulting in lymphedema of the lower legs. Previous studies have suggested that podoconiosis arises from the interplay of individual and environmental factors. Here, our aim was to understand the individual-level correlates of podoconiosis by comparing 460 podoconiosis-affected individuals and 707 unaffected controls.This was a case-control study carried out in six kebeles (the lowest governmental administrative unit in northern Ethiopia. Each kebele was classified into one of three endemicity levels: 'low' (prevalence 5%. A total of 142 (30.7% households had two or more cases of podoconiosis. Compared to controls, the majority of the cases, especially women, were less educated (OR = 1.7, 95% CI = 1.3 to 2.2, were unmarried (OR = 3.4, 95% CI = 2.6-4.6 and had lower income (t = -4.4, p<0.0001. On average, cases started wearing shoes ten years later than controls. Among cases, age of first wearing shoes was positively correlated with age of onset of podoconiosis (r = 0.6, t = 12.5, p<0.0001. Among all study participants average duration of shoe wearing was less than 30 years. Between both cases and controls, people in 'high' and 'medium' endemicity kebeles were less likely than people in 'low' endemicity areas to 'ever' have owned shoes (OR = 0.5, 95% CI = 0.4-0.7.Late use of shoes, usually after the onset of podoconiosis, and inequalities in education, income and marriage were found among cases, particularly among females. There were clustering of cases within households, thus interventions against podoconiosis will benefit from household-targeted case tracing. Most importantly, we identified a secular increase in shoe-wearing over recent years, which may give opportunities to promote shoe-wearing without increasing stigma among those at high risk of podoconiosis.

  5. Identification and medical utilization of incident cases of alcohol dependence: A population-based case-control study.

    Science.gov (United States)

    Pan, Chun-Hung; Li, Min-Shan; Yang, Tien-Wey; Huang, Ming-Chyi; Su, Sheng-Shiang; Hung, Yen-Ni; Chen, Chiao-Chicy; Kuo, Chian-Jue

    2018-05-05

    Patients with alcohol dependence (AD) often seek help from medical professionals due to alcohol-related diseases, but the overall distribution of medical specialties identifying new AD cases is unclear. We investigated how such cases were identified and how medical resources were utilized before the identification of AD in a nationwide cohort. We enrolled a population-based cohort (N = 1,000,000) using the National Health Insurance Research Database of Taiwan; 8181 cases with incident AD were retrieved between January 1, 2000, and December 31, 2010. For this nested case-control study, four controls were matched for age and sex with each case based on risk-set sampling. We measured various dimensions of medical utilization before AD was diagnosed, including department visited, physical comorbidity, and medication used. Conditional logistic regression was used for estimating the variables associated with AD. Patients living in less urbanized areas who were unemployed were more likely to develop AD. The highest proportions (34.2%) of AD cases were identified in the internal medicine department, followed by the emergency (22.3%) and psychiatry (18.7%) departments. AD patients had a higher risk of comorbid chronic hepatic disease (adjusted RR = 2.72, p identification of AD than controls. AD patients also had greater numbers of hospital admissions than controls, including non-psychiatric and psychiatric hospitalizations. Outpatient visit numbers were similar for AD patients and controls. The findings indicate that clinicians providing care in diverse medical settings should be prepared to screen for unhealthy alcohol use and to mitigate its detrimental effects. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Association between bullous pemphigoid and neurologic diseases: a case-control study.

    Science.gov (United States)

    Casas-de-la-Asunción, E; Ruano-Ruiz, J; Rodríguez-Martín, A M; Vélez García-Nieto, A; Moreno-Giménez, J C

    2014-11-01

    In the past 10 years, bullous pemphigoid has been associated with other comorbidities and neurologic and psychiatric conditions in particular. Case series, small case-control studies, and large population-based studies in different Asian populations, mainland Europe, and the United Kingdom have confirmed this association. However, no data are available for the Spanish population. This was an observational, retrospective, case-control study with 1:2 matching. Fifty-four patients with bullous pemphigoid were selected. We compared the percentage of patients in each group with concurrent neurologic conditions, ischemic heart disease, diabetes, chronic obstructive pulmonary disease, and solid tumors using univariate logistic regression. An association model was constructed with conditional multiple logistic regression. The case group had a significantly higher percentage of patients with cerebrovascular accident and/or transient ischemic attack (odds ratio [OR], 3.06; 95% CI, 1.19-7.87], dementia (OR, 5.52; 95% CI, 2.19-13.93), and Parkinson disease (OR, 5; 95% CI, 1.57-15.94). A significantly higher percentage of cases had neurologic conditions (OR, 6.34; 95% CI, 2.89-13.91). Dementia and Parkinson disease were independently associated with bullous pemphigoid in the multivariate analysis. Patients with bullous pemphigoid have a higher frequency of neurologic conditions. Copyright © 2013 Elsevier España, S.L.U. and AEDV. All rights reserved.

  7. A retrospective likelihood approach for efficient integration of multiple omics factors in case-control association studies.

    Science.gov (United States)

    Balliu, Brunilda; Tsonaka, Roula; Boehringer, Stefan; Houwing-Duistermaat, Jeanine

    2015-03-01

    Integrative omics, the joint analysis of outcome and multiple types of omics data, such as genomics, epigenomics, and transcriptomics data, constitute a promising approach for powerful and biologically relevant association studies. These studies often employ a case-control design, and often include nonomics covariates, such as age and gender, that may modify the underlying omics risk factors. An open question is how to best integrate multiple omics and nonomics information to maximize statistical power in case-control studies that ascertain individuals based on the phenotype. Recent work on integrative omics have used prospective approaches, modeling case-control status conditional on omics, and nonomics risk factors. Compared to univariate approaches, jointly analyzing multiple risk factors with a prospective approach increases power in nonascertained cohorts. However, these prospective approaches often lose power in case-control studies. In this article, we propose a novel statistical method for integrating multiple omics and nonomics factors in case-control association studies. Our method is based on a retrospective likelihood function that models the joint distribution of omics and nonomics factors conditional on case-control status. The new method provides accurate control of Type I error rate and has increased efficiency over prospective approaches in both simulated and real data. © 2015 Wiley Periodicals, Inc.

  8. National Case-Control Study of Homicide Offending and Methamphetamine Use

    Science.gov (United States)

    Stretesky, Paul B.

    2009-01-01

    The purpose of this study is to examine the relationship between methamphetamine use and homicide. To carry out this study, data from the National Household Survey on Drug Abuse and Survey of Inmates in State and Federal Correctional Facilities were combined to create a case-control design. The main exposure measure is methamphetamine use and the…

  9. Inverse association between atopy and melanoma: A case-control study

    NARCIS (Netherlands)

    Marasigan, V. (Vivien); M.-A. Morren (Marie-Anne); J. Lambert; Medaer, K. (Karen); Fieuws, S. (Steffen); T.E.C. Nijsten (Tamar); Garmyn, M. (Marjan)

    2017-01-01

    textabstractHeightened cutaneous immune surveillance in atopic patients may inhibit development of melanoma. The aim of this study was to analyse the association between atopy and melanoma (development and outcome). A total of 188 cases of melanoma and 596 healthy controls were interviewed by

  10. Modelling and Control of HIV/AIDS Propagation - A Case Study of ...

    African Journals Online (AJOL)

    Modelling and Control of HIV/AIDS Propagation - A Case Study of the Ashanti Region of Ghana. ... Open Access DOWNLOAD FULL TEXT ... in the Ashanti Region of Ghana for the period 1982 to 2001 with a view to assessing the level and impact of the pandemic as well as the effectiveness of the existing control measures.

  11. OPTIMIZED REAL-TIME CONTROL OF COMBINED SEWERAGE SYSTEMS: TWO CASE STUDIES

    Science.gov (United States)

    The paper presents results of two case studies of Real-Time Control (RTC) alternatives evaluations that were conducted on portions of sewerage systems near Paris, France and in Quebec City, Canada, respectively. The studies were performed at real-scale demonstration sites. RTC ...

  12. Leadership change: A case study analysis of strategy and control systems development

    Directory of Open Access Journals (Sweden)

    Alaudin Ahmadasri

    2017-01-01

    Full Text Available This paper reports on how a change of leadership at the CEO-level influences strategic practices and control systems development. The case study describes how the new chief executive developed and communicated his vision and strategy through control systems and structural change. The findings indicate that senior employees’ involvement in strategic plan development (through SLT mechanism in this case brought clarity and assurance to them. Meetings are important control mechanisms to structure the sharing of information and to enhance employee commitment and help decision making. It is argued leadership manifests through the interactions of leader with employees in many control practices. The findings have implications for family-owned businesses that are facing imminent change in leadership. They benefit founders/top managers that are about to change leadership of entrepreneurial firm to the next level by highlighting the importance of preparing leader’s capacity for an effective leadership role. The study also highlights some important factors which are seldom discussed in control theories.

  13. Neuropsychiatric manifestation of celiac disease: A case-control study in North India

    Directory of Open Access Journals (Sweden)

    Mahendra Nimel

    2016-01-01

    Full Text Available Background: Celiac disease (CD is an immune-mediated disease dependent on gluten. Prevalence of CD is about 1% and beside gastrointestinal complaints, neuropsychiatric symptoms may represent an atypical feature of CD. Some studies suggest that a gluten-free diet is effective in treating them. Settings and Design: This case-control study of 49 cases was done during the period of January to March 2013. Aim: To know the spectrum of psychiatric manifestations and cognitive functions in children with CD. Materials and Methods: We took 49 diagnosed cases of CD (based on the demonstration of IgA tissue transglutaminase antibodies and duodenal biopsy and compared with demographically matched control group (n = 50 on Seguin Form Board Test for cognitive functions and Behavioral Summarized Evaluation-Revised scale for assessment of psychiatric and behavior disturbances. All possible psychiatric diagnosis was made on the basis of International Statistical Classification of Disease and Related Health Problems-Tenth Revision criteria. Statistical Analysis: Statistical analyses were done by using Chi-square test and two-tailed P-values. Results: Neuropsychiatric manifestations were seen in 29% of cases as against 4% of controls which was statistically significant (P=0.001. Only four cases and 1 control fount to be mild mental retardation (P = 0.16. Autism, dyslexia, developmental delay, disruptive behavior disorder, and tic disorder present in cases were not found. Conclusion: Clinical manifestations of CD vary from typical malabsorption syndrome to neuropsychiatric manifestations. Those psychiatric patients who are not responding to standard pharmacological modalities, a diagnosis of CD should be taken into consideration. Only behavioral problem can be the sole clinical manifestation of CD.

  14. Selection bias in population-based cancer case-control studies due to incomplete sampling frame coverage.

    Science.gov (United States)

    Walsh, Matthew C; Trentham-Dietz, Amy; Gangnon, Ronald E; Nieto, F Javier; Newcomb, Polly A; Palta, Mari

    2012-06-01

    Increasing numbers of individuals are choosing to opt out of population-based sampling frames due to privacy concerns. This is especially a problem in the selection of controls for case-control studies, as the cases often arise from relatively complete population-based registries, whereas control selection requires a sampling frame. If opt out is also related to risk factors, bias can arise. We linked breast cancer cases who reported having a valid driver's license from the 2004-2008 Wisconsin women's health study (N = 2,988) with a master list of licensed drivers from the Wisconsin Department of Transportation (WDOT). This master list excludes Wisconsin drivers that requested their information not be sold by the state. Multivariate-adjusted selection probability ratios (SPR) were calculated to estimate potential bias when using this driver's license sampling frame to select controls. A total of 962 cases (32%) had opted out of the WDOT sampling frame. Cases age <40 (SPR = 0.90), income either unreported (SPR = 0.89) or greater than $50,000 (SPR = 0.94), lower parity (SPR = 0.96 per one-child decrease), and hormone use (SPR = 0.93) were significantly less likely to be covered by the WDOT sampling frame (α = 0.05 level). Our results indicate the potential for selection bias due to differential opt out between various demographic and behavioral subgroups of controls. As selection bias may differ by exposure and study base, the assessment of potential bias needs to be ongoing. SPRs can be used to predict the direction of bias when cases and controls stem from different sampling frames in population-based case-control studies.

  15. Sensory impairments and wrist fractures: A case-control study

    Directory of Open Access Journals (Sweden)

    Bergthora Baldursdottir

    2017-12-01

    Full Text Available Objectives: To investigate vestibular function, foot sensation, postural control and functional abilities, and to evaluate whether these variables are associated with fall-related wrist fracture. Methods: A case-control study was conducted with 98 subjects, age range 50–75 years, who had sustained a fall-related wrist fracture. Forty-eight sex-, age- and physical activity-matched individuals, with no previous history of wrist fracture, served as controls. Measurements included: head-shake test (HST, tuning fork, biothesiometer, Semmes-Weinstein monofilaments (MF, Sensory Organization Test (SOT, Five-Times-Sit-to-Stand Test (FTSTS, 10-m walk test (10MWT, Activities-specific Balance Confidence (ABC, and the Dizziness Handicap Inventory (DHI scales. Logistic regression models were used to determine associations of variables with a fall-related wrist fracture. Results: Vestibular asymmetry was apparent in 82% of wrist fracture subjects and 63% of controls (p = 0.012. Plantar pressure sensation (p <0.001, SOT composite scores (p < 0.001, 10MWT (p <0.001, FTSTS (p <0.001, ABC (p <0.001 and DHI (p <0.005 were significantly poorer among cases than controls. A positive HST (odds ratio (OR 5.424; p = 0.008 and monofilament sensation (OR 3.886; p = 0.014 showed the strongest associations with having a fall-related wrist fracture. Conclusion: Asymmetrical vestibular function and reduced plantar pressure sensation are associated with fall-related wrist fractures among the ageing population. These factors are potential targets for future interventions.

  16. Determinants of Internet Addiction among Adolescents: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Artemis Tsitsika

    2011-01-01

    Full Text Available Internet Addiction (IA is associated with adverse psychosocial development and mental disorders. The study aims were to evaluate the psychosocial profiles and psychiatric comorbidities associated with IA among adolescents. A case-control study was conducted among 129 adolescents in the outpatient setting of the Adolescent Health Unit of the Second University Department of Pediatrics in Athens, Greece. The case group consisted of 86 adolescents with IA as evaluated following psychiatric interview with two independent examiners. The control group consisted of 43 adolescents without IA, frequency matched for age and gender with case group participants. The study findings indicated that adolescents with IA were significantly more likely to have divorced parents (p = 0.012 and/or dysfunctional familial relationships (p < 0.0001. The proportion of adolescents with poor academic performance (p < 0.0001 and unexcused school absences (p = 0.004 was greater among those with IA. Moreover, approximately two-thirds of the adolescents with IA were engaged in high-risk behaviors (p < 0.0001. Finally, adolescents with IA were 3.89 times more likely to present with comorbid psychiatric conditions (CI 95%: 1.19–12.70, including depression (10.5 vs. 0%; p = 0.022. Adolescent IA is associated with deterred familial functions, poor academic performance, engagement in high-risk behaviors, and an augmented likelihood for depression.

  17. Perinatal mortality and associated risk factors: a case control study ...

    African Journals Online (AJOL)

    BACKGROUND: Perinatal mortality is reported to be five times higher in developing than in developed nations. Little is known about the commonly associated risk factors for perinatal mortality in Southern Nations National Regional State of Ethiopia. METHODS: A case control study for perinatal mortality was conducted in ...

  18. Internet-based control recruitment for a case-control study of major risk factors for stroke in Korea: lessons from the experience.

    Science.gov (United States)

    Park, Jong-Moo; Cho, Yong-Jin; Lee, Kyung Bok; Park, Tai Hwan; Lee, Soo Joo; Han, Moon-Ku; Ko, Youngchai; Lee, Jun; Cha, Jae-Kwan; Lee, Byung-Chul; Yu, Kyung-Ho; Oh, Mi-Sun; Lee, Ji Sung; Lee, Juneyoung; Bae, Hee-Joon

    2014-01-01

    This study aimed to estimate the population-attributable risks (PARs) of 9 major risk factors for stroke in Korea through a case-control study and to test the feasibility and validity of internet-based control recruitment. From April 2008 to September 2009, controls were enrolled via internet after providing consent for participation through a web-based survey. The cases included patients who were admitted to the participating centers due to acute stroke or transient ischemic attack within 7 days of onset during the study period. Each control was age- and sex-matched with 2 cases. Adjusted odd ratios, age-standardized prevalence, and PARs were estimated for the 9 major risk factors using the prevalence of risk factors in the control group and the age and sex characteristics from Korea's national census data. In total, 1041 controls were matched to 2082 stroke cases. Because of a shortage of elderly controls in the internet-based recruitment, 248 controls were recruited off-line. The PARs were 23.44%, 10.95%, 51.32%, and 6.35% for hypertension, diabetes, smoking, and stroke history, respectively. Hypercholesterolemia, atrial fibrillation, obesity, coronary heart disease, and a family history of stroke were not associated with stroke. Comparison with education and religion of the control group with that mentioned in the national census data showed a notable difference. The study results imply that internet-based control recruitment for a case-control study requires careful selection of risk factors with high self-awareness and effective strategies to facilitate the recruitment of elderly participants. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  19. Residents in difficulty—just slower learners? A case-control study

    DEFF Research Database (Denmark)

    O'Neill, Lotte; Norberg, Karen; Thomsen, Maria

    2014-01-01

    were matched for graduation year. Medical school exam failures, grades, completion time, and academic dispensations as predictors of case status were examined with conditional logistic regression. RESULTS In total 89 cases and 343 controls were identified. The total number of medical school re......-examinations and the time it took to complete medical school were significant individual predictors of subsequent difficulties (deceleration, transferral or dropout) in residency whereas average medical school grades were not. CONCLUSIONS Residents in difficulty eventually reached similar competence levels as controls...... during medical school; however, they needed more exam attempts and longer time to complete their studies, and so seemed to be slower learners. A change from “fixed-length variable-outcome programmes” to “fixed-outcome variable-length programmes” has been proposed as a way of dealing with the fact...

  20. Case studies in control putting theory to work

    CERN Document Server

    Juričić, Đani

    2013-01-01

    Case Studies in Control presents a framework to facilitate the use of advanced control concepts in real systems based on two decades of research and over 150 successful applications for industrial end-users from various backgrounds. In successive parts the text approaches the problem of putting the theory to work from both ends, theoretical and practical. The first part begins with a stress on solid control theory and the shaping of that theory to solve particular instances of practical problems. It emphasizes the need to establish by experiment whether a model-derived solution will perform properly in reality. The second part focuses on real industrial applications based on the needs and requirements of end-users. Here, the engineering approach is dominant but with theoretical input of varying degree depending on the particular process involved. Following the illustrations of the progress that can be made from either extreme of the well-known theory–practice divide, the text proceeds to a third part relate...

  1. Case-control study on infant mortality in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Mendes Karina Giane

    2006-01-01

    Full Text Available OBJECTIVE: To identify risk factors associated with infant mortality and, more specifically, with neonatal mortality. METHODS: A case-control study was carried out in the municipality of Caxias do Sul, Southern Brazil. Characteristics of prenatal care and causes of mortality were assessed for all live births in the 2001-2002 period with a completed live-birth certificate and whose mothers lived in the municipality. Cases were defined as all deaths within the first year of life. As controls, there were selected the two children born immediately after each case in the same hospital, who were of the same sex, and did not die within their first year of life. Multivariate analysis was performed using conditional logistic regression. RESULTS: There was a reduction in infant mortality, the greatest reduction was observed in the post-neonatal period. The variables gestational age (<36 weeks, birth weight (<2,500 g, and 5-minute Apgar (<6 remained in the final model of the multivariate analysis, after adjustment. CONCLUSIONS: Perinatal conditions comprise almost the totality of neonatal deaths, and the majority of deaths occur at delivery. The challenge for reducing infant mortality rate in the city is to reduce the mortality by perinatal conditions in the neonatal period.

  2. Organohalogen body burdens in a breast cancer case-control study

    Energy Technology Data Exchange (ETDEWEB)

    Petreas, M.; She, J.; Visita, P.; Winkler, J. [Hazardous Materials Lab., California Dept. of Toxic Substances Control, Berkeley, CA (United States); Hurley, S.; Smith, D.; Reynolds, P. [Environmental Health Investigations Branch, California Dept. of Health Services, Oakland, CA (United States); Jeffrey, S.; Mahoney, E. [Dept. of Surgery, Stanford Univ. School of Medicine, Stanford, CA (United States)

    2004-09-15

    Due to their lipophilic properties, dioxins (PCDD/PCDFs) and other organohalogen compounds bioaccumulate in the food chain, with diet accounting for over 90% of non-occupational exposures. To date, few epidemiologic studies have examined the relationship between dioxins and breast cancer in human populations. Most have examined risks in occupational cohorts or in populations exposed to dioxins from the Seveso accident6-8. Results from these studies have been conflicting and have largely been limited by a lack of individual-level measures of exposure, small numbers of cases, and inability to account for established breast cancer risk factors. Very little is known about the potential health effects of low-level environmental dioxin contamination. We present data on PCDD/PCDFs, organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in adipose tissues of women participating in a breast cancer case-control study centered in the San Francisco Bay Area. In addition, we examine distributions of these chemicals in breast and abdominal adipose of women undergoing mastectomies with concurrent breast reconstruction. If concentrations were equivalent, use of abdominal adipose would greatly enhance the pool for controls for future epidemiological studies.

  3. Intrahousehold resource allocation and child growth in Mozambique: an ethnographic case-control study.

    Science.gov (United States)

    Pfeiffer, J; Gloyd, S; Ramirez Li, L

    2001-07-01

    This study examines the effect of intrahousehold cash income control and decision-making patterns on child growth in the rural town of Sussundenga in Manica Province, Mozambique. A case-control study design was used to examine the influence of men's and women's disaggregated cash incomes on child growth. The research tested whether greater maternal share of household cash income was associated with (1) increased maternal decision-making and bargaining power in the household, and (2) better child growth. Fifty case households, with children 1-4 years old exhibiting poor growth, were matched with 50 control households of similar socioeconomic status in which all children under five demonstrated healthy growth. Data were gathered on gender-specific income generation and expenditure, specific intrahousehold allocation processes, diet, and sociodemographic variables using a formal survey. Key informant interviews, focus groups, and observation over one year provided ethnographic context for the case-control findings. Case-control differences were analyzed using McNemar's test, paired t-test, and conditional logistic regression. In spite of matching households for socioeconomic status, control household incomes were still slightly greater than cases. Male spouse income was also higher among controls while maternal income, and maternal proportion of household income, were not significantly different. Household meat, fish and poultry consumption, and maternal education were significantly greater among control households than cases. Greater maternal share of household income was not associated with greater maternal decision-making around cash. However, mothers must spend what little cash they earn on daily food supplies and usually request additional cash from spouses to cover these costs. There is evidence that if mothers earn enough to cover these socially prescribed costs, they can spend cash for other needs. Above this threshold, women's earnings may confer more

  4. Risk factors for syphilis in women: case-control study

    Directory of Open Access Journals (Sweden)

    Vilma Costa de Macêdo

    2017-08-01

    Full Text Available ABSTRACT OBJECTIVE To determine the sociodemographic, behavioral, and health care factors related to the occurrence of syphilis in women treated at public maternity hospitals. METHODS This is a case-control study (239 cases and 322 controls with women admitted to seven maternity hospitals in the municipality of Recife, Brazil, from July 2013 to July 2014. Eligible women were recruited after the result of the VDRL (Venereal Disease Research Laboratory under any titration. The selection of cases and controls was based on the result of the serology for syphilis using ELISA (enzyme-linked immunosorbent assay. The independent variables were grouped into: sociodemographic, behavioral, clinical and obstetric history, and health care in prenatal care and maternity hospital. Information was obtained by interview, during hospitalization, with the application of a questionnaire. Odds ratios and 95% confidence intervals were estimated using logistic regression to identify the predicting factors of the variable to be explained. RESULTS The logistic regression analysis identified as determinant factors for gestational syphilis: education level of incomplete basic education or illiterate (OR = 2.02, lack of access to telephone (OR = 2.4, catholic religion (OR = 1.70 , four or more pregnancies (OR = 2.2, three or more sexual partners in the last year (OR = 3.1, use of illicit drugs before the age of 18 (OR = 3.0, and use of illicit drugs by the current partner (OR = 1.7. Only one to three prenatal appointments (OR = 3.5 and a previous history of sexually transmitted infection (OR = 9.7 were also identified as determinant factors. CONCLUSIONS Sociodemographic, behavioral, and health care factors are associated with the occurrence of syphilis in women and should be taken into account in the elaboration of universal strategies aimed at the prevention and control of syphilis, but with a focus on situations of greater vulnerability.

  5. Risk factors for syphilis in women: case-control study

    Science.gov (United States)

    de Macêdo, Vilma Costa; de Lira, Pedro Israel Cabral; de Frias, Paulo Germano; Romaguera, Luciana Maria Delgado; Caires, Silvana de Fátima Ferreira; Ximenes, Ricardo Arraes de Alencar

    2017-01-01

    ABSTRACT OBJECTIVE To determine the sociodemographic, behavioral, and health care factors related to the occurrence of syphilis in women treated at public maternity hospitals. METHODS This is a case-control study (239 cases and 322 controls) with women admitted to seven maternity hospitals in the municipality of Recife, Brazil, from July 2013 to July 2014. Eligible women were recruited after the result of the VDRL (Venereal Disease Research Laboratory) under any titration. The selection of cases and controls was based on the result of the serology for syphilis using ELISA (enzyme-linked immunosorbent assay). The independent variables were grouped into: sociodemographic, behavioral, clinical and obstetric history, and health care in prenatal care and maternity hospital. Information was obtained by interview, during hospitalization, with the application of a questionnaire. Odds ratios and 95% confidence intervals were estimated using logistic regression to identify the predicting factors of the variable to be explained. RESULTS The logistic regression analysis identified as determinant factors for gestational syphilis: education level of incomplete basic education or illiterate (OR = 2.02), lack of access to telephone (OR = 2.4), catholic religion (OR = 1.70 ), four or more pregnancies (OR = 2.2), three or more sexual partners in the last year (OR = 3.1), use of illicit drugs before the age of 18 (OR = 3.0), and use of illicit drugs by the current partner (OR = 1.7). Only one to three prenatal appointments (OR = 3.5) and a previous history of sexually transmitted infection (OR = 9.7) were also identified as determinant factors. CONCLUSIONS Sociodemographic, behavioral, and health care factors are associated with the occurrence of syphilis in women and should be taken into account in the elaboration of universal strategies aimed at the prevention and control of syphilis, but with a focus on situations of greater vulnerability. PMID:28832758

  6. Control selection and confounding factors: A lesson from a Japanese case-control study to examine acellular pertussis vaccine effectiveness.

    Science.gov (United States)

    Ohfuji, Satoko; Okada, Kenji; Nakano, Takashi; Ito, Hiroaki; Hara, Megumi; Kuroki, Haruo; Hirota, Yoshio

    2017-08-24

    When using a case-control study design to examine vaccine effectiveness, both the selection of control subjects and the consideration of potential confounders must be the important issues to ensure accurate results. In this report, we described our experience from a case-control study conducted to evaluate the effectiveness of acellular pertussis vaccine combined with diphtheria-tetanus toxoids (DTaP vaccine). Newly diagnosed pertussis cases and age- and sex-matched friend-controls were enrolled, and the history of DTaP vaccination was compared between groups. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for development of pertussis. After adjustment for potential confounders, four doses of DTaP vaccination showed a lower OR for pediatrician-diagnosed pertussis (OR=0.11, 95% CI, 0.01-0.99). In addition, the decreasing OR of four doses vaccination was more pronounced for laboratory-confirmed pertussis (OR=0.07, 95%CI, 0.01-0.82). Besides, positive association with pertussis was observed in subjects with a history of steroid treatment (OR=5.67) and those with a recent contact with a lasting cough (OR=4.12). When using a case-control study to evaluate the effectiveness of vaccines, particularly those for uncommon infectious diseases such as pertussis, the use of friend-controls may be optimal due to the fact that they shared a similar experience for exposure to the pathogen as the cases. In addition, to assess vaccine effectiveness as accurately as possible, the effects of confounding should be adequately controlled with a matching or analysis technique. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. Birth outcomes of cases with isolated atrial septal defect type II--a population-based case-control study.

    Science.gov (United States)

    Vereczkey, Attila; Kósa, Zsolt; Csáky-Szunyogh, Melinda; Urbán, Róbert; Czeizel, Andrew E

    2013-07-01

    In general, epidemiological studies have evaluated cases with congenital cardiovascular abnormalities together. The aim of this study is to describe the birth outcomes of cases with isolated/single atrial septal defect type II (ASD-II, i.e. only a fossa ovalis defect) after surgical correction or lethal outcome in the light of maternal sociodemographic data. Comparison of birth outcomes and maternal characteristics of cases with ASD-II and controls without defect. The population-based Hungarian Case-Control Surveillance of Congenital Abnormalities. Hungarian newborn infants with or without ASD-II. Medically recorded birth outcomes, maternal age and birth order were evaluated. Marital and employment status was based on maternal information. The lifestyle factors were analyzed in a subsample of mothers visited at home based on a personal interview with mothers and their close relatives, and the family consensus was accepted. Mean gestational age at delivery and birthweight, rate of preterm birth and low birthweight, maternal age, birth order, marital and employment status. The evaluation of 471 cases with ASD-II and 38,151 controls without any defects showed a female excess in cases with ASD-II, having shorter gestational age and lower mean birthweight, and thus a higher rate of preterm births and low birthweight. Intrauterine growth restriction and shorter gestational age were found in cases with ASD-II, particularly in female children. These factors may have a general developmental process in which there was not closure of the foramen ovale, thus echocardiographic screening of these babies might be of value. © 2012 The Authors Acta Obstetricia et Gynecologica Scandinavica © 2012 Nordic Federation of Societies of Obstetrics and Gynecology.

  8. Effectiveness of inactivated quadrivalent influenza vaccine in the 2015/2016 season as assessed in both a test-negative case-control study design and a traditional case-control study design.

    Science.gov (United States)

    Kimiya, Takahisa; Shinjoh, Masayoshi; Anzo, Makoto; Takahashi, Hiroki; Sekiguchi, Shinichiro; Sugaya, Norio; Takahashi, Takao

    2018-04-21

    Both traditional case-control studies (TCCSs) and test-negative case-control studies (TNCCSs) are commonly used to assess influenza vaccine effectiveness (VE). To compensate for the fact that observational studies are susceptible to bias, we combined both methods to assess VE in one geographical area during the 2015/2016 season, when influenza A (H1N1)pdm was dominant. Our TNCCS covered 331 children aged 6 months to 15 years who visited our hospital with fever, including 182 with influenza, and our TCCS covered 812 pediatric outpatients aged 6 months to 15 years, including 214 with influenza. Influenza infection and vaccination history were reviewed, and VE was calculated as (1 - odds ratio) × 100. In the TNCCS, VE against influenza A was 68% (95% CI 47-81) overall, and 70% (48-83) for those given two doses; against influenza B, VE was 37% (- 12-64) overall and 49% (2-74) for two doses. In the TCCS, VE against influenza A was 44% (15-63) overall and 44% (13-64) for two doses, and VE against influenza B was 24% (- 19-52) overall and 41% (3-64) for two doses. Both studies confirmed significant VE against influenza A, significant two-dose VE against influenza B, and better two-dose VE than one-dose VE. What is Known: • Influenza vaccine effectiveness (VE) varies from year to year. • Observational studies are conventionally used for VE assessment. However, they are inherently susceptible to bias and confounding. What is New: • This is the first report of influenza VE assessment using more than one observational study and performed in a specific area during the same season. • VE estimates obtained in our traditional case-control study were lower than those in our test-negative case-control study, but both studies found significant VE against influenza.

  9. Risk factors for Creutzfeldt-Jakob disease: a reanalysis of case-control studies.

    NARCIS (Netherlands)

    D.P.W.M. Wientjens (Dorothee); Z. Davanipour; K. Kondo; W.B. Matthews; R.G. Will (Robert); C.M. van Duijn (Cornelia); A. Hofman (Albert)

    1996-01-01

    textabstractTo review the evidence for risk factors of Creutzfeldt-Jakob disease (CJD), we pooled and reanalyzed the raw data of three case-control studies. The pooled data set comprised 178 patients and 333 control subjects. The strength of association between CJD and putative risk factors was

  10. Smoking, alcohol, and coffee consumption preceding Parkinson's disease: a case-control study.

    Science.gov (United States)

    Benedetti, M D; Bower, J H; Maraganore, D M; McDonnell, S K; Peterson, B J; Ahlskog, J E; Schaid, D J; Rocca, W A

    2000-11-14

    To study the association of PD with preceding smoking, alcohol, and coffee consumption using a case-control design. The authors used the medical records linkage system of the Rochester Epidemiology Project to identify 196 subjects who developed PD in Olmsted County, MN, during the years 1976 to 1995. Each incident case was matched by age (+/-1 year) and sex to a general population control subject. The authors reviewed the complete medical records of cases and control subjects to abstract exposure information. For coffee consumption, the authors found an OR of 0.35 (95% CI = 0.16 to 0.78, p = 0.01), a dose-effect trend (p = 0.003), and a later age at PD onset in cases who drank coffee compared with those who never did (median 72 versus 64 years; p = 0.0002). The inverse association with coffee remained significant after adjustment for education, smoking, and alcohol drinking and was restricted to PD cases with onset at age coffee drinking and PD; however, this association does not imply that coffee has a direct protective effect against PD. Alternative explanations for the association should be considered.

  11. Vitamin D and Fracture Risk in Early Childhood: A Case-Control Study

    Science.gov (United States)

    Anderson, Laura N.; Heong, Sze Wing; Chen, Yang; Thorpe, Kevin E.; Adeli, Khosrow; Howard, Andrew; Sochett, Etienne; Birken, Catherine S.; Parkin, Patricia C.; Maguire, Jonathon L.; Abdullah, Kawsari; Anderson, Laura N.; Birken, Catherine S.; Borkhoff, Cornelia M.; Carsley, Sarah; Chen, Yang; Katz-Lavigne, Mikael; Kavikondala, Kanthi; Kowal, Christine; Maguire, Jonathon L.; Mason, Dalah; Omand, Jessica; Parkin, Patricia C.; Persaud, Navindra; van den Heuvel, Meta; Baker, Jillian; Barozzino, Tony; Bonifacio, Joey; Campbell, Douglas; Cheema, Sohail; Chisamore, Brian; Danayan, Karoon; Das, Paul; Derocher, Mary Beth; Do, Anh; Dorey, Michael; Freeman, Sloane; Fung, Keewai; Guiang, Charlie; Handford, Curtis; Hatch, Hailey; Jacobson, Sheila; Kiran, Tara; Knowles, Holly; Kwok, Bruce; Lakhoo, Sheila; Lam-Antoniades, Margarita; Lau, Eddy; Leung, Fok-Han; Loo, Jennifer; Mahmoud, Sarah; Moodie, Rosemary; Morinis, Julia; Naymark, Sharon; Neelands, Patricia; Owen, James; Peer, Michael; Perlmutar, Marty; Persaud, Navindra; Pinto, Andrew; Porepa, Michelle; Ramji, Nasreen; Ramji, Noor; Rosenthal, Alana; Saunderson, Janet; Saxena, Rahul; Sgro, Michael; Shepherd, Susan; Smiltnieks, Barbara; Taylor, Carolyn; Weisdors, Thea; Wijayasinghe, Sheila; Wong, Peter; Ying, Ethel; Young, Elizabeth

    2017-01-01

    Abstract The objective of this study was to evaluate the association of vitamin D intake and serum levels with fracture risk in children under 6 years of age. A case-control study was conducted in Toronto, Ontario, Canada. Cases were recruited from the fracture clinic at the Hospital for Sick Children, and matched controls were obtained from the TARGet Kids! primary-care research network. Controls were matched to cases on age, sex, height, and season. Fracture risk was estimated from conditional logistic regression, with adjustment for skin type, fracture history, waist circumference, outdoor free play, neighborhood income, soda consumption, and child's birth weight. A total of 206 cases were recruited during May 2009–April 2013 and matched to 343 controls. Serum 25-hydroxyvitamin D concentration (per 10-nmol/L increment: adjusted odds ratio (aOR) = 0.95, 95% confidence interval (CI): 0.88, 1.03) and intake of cow's milk (2 cups/day vs. 2 cups/day: aOR = 1.39 (95% CI: 0.85, 2.23)) were not significantly associated with reduced odds of fracture. A statistically significant association was observed between child use of vitamin D supplements and decreased odds of fracture (yes vs. no: aOR = 0.42, 95% CI: 0.25, 0.69). Vitamin D supplementation, but not serum 25-hydroxyvitamin D level or milk intake, was associated with reduced fracture risk among these healthy young children. PMID:28459987

  12. Lichen planus and Hepatitis C: A case-control study | Elagraa ...

    African Journals Online (AJOL)

    Background The exact cause of LP is not known. However, the association of lichen planus with hepatitis C virus (HCV) infection has been reported in literature. A wide variation in the reported prevalence of HCV infection in patients with lichen planus in different geographical areas was observed. This casecontrol study ...

  13. A Matched Case-Control Study of Risk Factors for Breast Cancer Risk in Vietnam

    Directory of Open Access Journals (Sweden)

    J. Nguyen

    2016-01-01

    Full Text Available Background. Vietnam has a low age-standardized incidence of breast cancer, but the incidence is rising rapidly with economic development. We report data from a matched case-control study of risk factors for breast cancer in the largest cancer hospital in Vietnam. Methods. 492 incident breast cancer cases unselected for family history or age at diagnosis and 1306 control women age 25–75 were recruited from the National Cancer Hospital (BVK, Hanoi. Structured interviews were conducted and pathology data was centrally reported at the National Cancer Hospital of Vietnam, in Hanoi. Results. Our analysis included 294 matched pairs. Mean age at diagnosis was 46.7 years. Lower mean parity, older age at first parity, increasing weight and BMI at age 18, and increasing BMI at diagnosis were positively correlated with breast cancer cases compared to controls. Age at first menarche and duration of breastfeeding were not statistically different between cases and controls. Conclusions. In this study we demonstrate that breast cancer in Vietnam is associated with some but not all of the published risk factors from Western populations. Our data is consistent with other studies of breast cancer in Asian populations.

  14. Occupational lifting is associated with hip osteoarthritis: a Japanese case-control study.

    Science.gov (United States)

    Yoshimura, N; Sasaki, S; Iwasaki, K; Danjoh, S; Kinoshita, H; Yasuda, T; Tamaki, T; Hashimoto, T; Kellingray, S; Croft, P; Coggon, D; Cooper, C

    2000-02-01

    Hip osteoarthritis (OA) is a frequent cause of pain and disability in Western countries, but the disorder is less common in Japan. A case-control study in Britain found obesity, hip injury, and occupational lifting to be associated with hip OA among men and women. However, there are few epidemiological studies concerning factors associated with hip OA in Japan. We performed a comparable case-control study of the disorder in Japan, and contrasted the findings with those from Britain. The study was carried out in 2 health districts in Wakayama Prefecture, Japan. Cases were men and women aged > or = 45 years listed for total hip arthroplasty due to OA over one year, and who did not have an established cause of secondary OA (e.g., rheumatoid arthritis, ankylosing spondylitis). For each case, a control was selected randomly from the general population and was individually matched to the case for age, sex, and district of residence. Cases and controls were interviewed with a structured questionnaire about medical history, physical activity, socioeconomic factors, and occupation. Measurements were made of height and weight. One hundred fourteen cases (103 women, 11 men) were compared with 114 controls. We found no relationship between obesity and hip OA (OR = 1.0, 95% CI 0.5-1.9; highest vs lowest thirds of distribution of body mass index). There was, however, a statistically significant association between occupational lifting and hip OA, such that regular lifting of 25 kg in the individual's first job (OR = 3.6, 95% CI 1.3-9.7) or of 50 kg in their main job (OR = 4.0, 95% CI 1.1-14.2) was associated with increased risk of hip OA. These associations remained after adjustment for potential confounding variables. In contrast, those subjects who spent > 2 h each day sitting during their first job were significantly less likely to have the disorder (crude OR = 0.5, 95% CI 0.3-0.9). This association also remained statistically significant after adjustment for potential risk

  15. Case-control study of amyotrophic lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Deapen, D.M.; Henderson, B.E.

    1986-05-01

    The authors conducted a study of 518 amyotrophic lateral sclerosis patients identified between 1977 and 1979 and 518 controls to investigate putative risk factors for this disease. Occupations at risk of electrical exposure were reported more often by patients (odds ratio (OR) = 3.8, 95% confidence interval (CI) = 1.4-13.0) as were electrical shocks producing unconsciousness (OR = 2.8, 95% CI = 1.0-9.9). Although an overall excess of physical trauma associated with unconsciousness was observed in the amyotrophic lateral sclerosis patients (OR = 1.6, 95% CI = 1.0-2.4), the effect was inversely associated with duration of the unconscious episodes, suggesting an effect of recall bias. Only slight differences were found for surgical traumata to the nervous system. Parkinsonism was reported more often among first degree relatives of cases (OR = 2.7, 95% CI = 1.1-7.6). The frequencies of prior poliomyelitis or other central nervous system diseases were similar for patients and controls. Occupational exposure to selected toxic substances was similar for patients and controls except for the manufacture of plastics (OR = 3.7, 95% CI = 1.0-20.5), although few details of these exposures were provided. No differences in occupations with exposure to animal skins or hides were observed.

  16. Dietary patterns and adult asthma: population-based case-control study.

    Science.gov (United States)

    Bakolis, I; Hooper, R; Thompson, R L; Shaheen, S O

    2010-05-01

    Epidemiological studies of diet and asthma have focused on relations with intakes of individual nutrients and foods and evidence has been conflicting. Few studies have examined associations with dietary patterns. We carried out a population-based case-control study of asthma in adults aged between 16 and 50 in South London, UK. Information about usual diet was obtained by food frequency questionnaire and we used principal components analysis to define five dietary patterns in controls. We used logistic and linear regression, controlling for confounders, to relate these patterns to asthma, asthma severity, rhinitis and chronic bronchitis in 599 cases and 854 controls. Overall, there was weak evidence that a 'vegetarian' dietary pattern was positively associated with asthma [adjusted odds ratio comparing top vs bottom quintile of pattern score 1.43 (95% CI: 0.93-2.20), P trend 0.075], and a 'traditional' pattern (meat and vegetables) was negatively associated [OR 0.68 (0.45-1.03), P trend 0.071]. These associations were stronger amongst nonsupplement users (P trend 0.030 and 0.001, respectively), and the association with the 'vegetarian' pattern was stronger amongst whites (P trend 0.008). No associations were observed with asthma severity. A 'prudent' dietary pattern (wholemeal bread, fish and vegetables) was positively associated with chronic bronchitis [OR 2.61 (1.13-6.05), P trend 0.025], especially amongst nonsupplement users (P trend 0.002). Overall there were no clear relations between dietary patterns and adult asthma; associations in nonsupplement users and whites require confirmation. The finding for chronic bronchitis was unexpected and also requires replication.

  17. Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

    Science.gov (United States)

    Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

    2015-07-01

    Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

  18. Is opium a real risk factor for esophageal cancer or just a methodological artifact? Hospital and neighborhood controls in case-control studies.

    Science.gov (United States)

    Shakeri, Ramin; Kamangar, Farin; Nasrollahzadeh, Dariush; Nouraie, Mehdi; Khademi, Hooman; Etemadi, Arash; Islami, Farhad; Marjani, Hajiamin; Fahimi, Saman; Sepehr, Alireza; Rahmati, Atieh; Abnet, Christian C; Dawsey, Sanford M; Brennan, Paul; Boffetta, Paolo; Malekzadeh, Reza; Majdzadeh, Reza

    2012-01-01

    Control selection is a major challenge in epidemiologic case-control studies. The aim of our study was to evaluate using hospital versus neighborhood control groups in studying risk factors of esophageal squamous cell carcinoma (ESCC). We compared the results of two different case-control studies of ESCC conducted in the same region by a single research group. Case definition and enrollment were the same in the two studies, but control selection differed. In the first study, we selected two age- and sex-matched controls from inpatient subjects in hospitals, while for the second we selected two age- and sex-matched controls from each subject's neighborhood of residence. We used the test of heterogeneity to compare the results of the two studies. We found no significant differences in exposure data for tobacco-related variables such as cigarette smoking, chewing Nass (a tobacco product) and hookah (water pipe) usage, but the frequency of opium usage was significantly different between hospital and neighborhood controls. Consequently, the inference drawn for the association between ESCC and tobacco use did not differ between the studies, but it did for opium use. In the study using neighborhood controls, opium use was associated with a significantly increased risk of ESCC (adjusted OR 1.77, 95% CI 1.17-2.68), while in the study using hospital controls, this was not the case (OR 1.09, 95% CI 0.63-1.87). Comparing the prevalence of opium consumption in the two control groups and a cohort enrolled from the same geographic area suggested that the neighborhood controls were more representative of the study base population for this exposure. Hospital and neighborhood controls did not lead us to the same conclusion for a major hypothesized risk factor for ESCC in this population. Our results show that control group selection is critical in drawing appropriate conclusions in observational studies.

  19. Control assessment for heat integrated systems. An industrial case study for ethanol recovery

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Huusom, Jakob Kjøbsted; Sin, Gürkan

    2013-01-01

    Heat integration is essential for reducing the energy consumption of process industries. However, it may render the dynamic operation more interactive and difficult to control. This paper assesses the implications of heat integration in controllability and performance in energy reduction....... The assessment, both on open loop and closed loop, was carried out based on an industrial case study and compared to a modified case without heat integration. Although the heat integrated system displayed a certain deterioration of controllability, the control system made possible an efficient operation....... The reduction of energy consumption achieved thanks to heat integration was considerably larger than the losses due to poor control of the process, confirming the importance of heat integration in energy intensive processes....

  20. Optimizing the construction of devices to control inaccesible surfaces - case study

    Science.gov (United States)

    Niţu, E. L.; Costea, A.; Iordache, M. D.; Rizea, A. D.; Babă, Al

    2017-10-01

    The modern concept for the evolution of manufacturing systems requires multi-criteria optimization of technological processes and equipments, prioritizing associated criteria according to their importance. Technological preparation of the manufacturing can be developed, depending on the volume of production, to the limit of favourable economical effects related to the recovery of the costs for the design and execution of the technological equipment. Devices, as subsystems of the technological system, in the general context of modernization and diversification of machines, tools, semi-finished products and drives, are made in a multitude of constructive variants, which in many cases do not allow their identification, study and improvement. This paper presents a case study in which the multi-criteria analysis of some structures, based on a general optimization method, of novelty character, is used in order to determine the optimal construction variant of a control device. The rational construction of the control device confirms that the optimization method and the proposed calculation methods are correct and determine a different system configuration, new features and functions, and a specific method of working to control inaccessible surfaces.

  1. Case-control study of radon and lung cancer in New Jersey

    International Nuclear Information System (INIS)

    Wilcox, H. B.; Al-Zoughool, M.; Garner, M. J.; Jiang, H.; Klotz, J. B.; Krewski, D.; Nicholson, W. J.; Schoenberg, J. B.; Villeneuve, P. J.; Zielinski, J. M.

    2008-01-01

    Radon is known to cause lung cancer in humans; however, there remain uncertainties about the effects associated with residential exposures. This case-control study of residential radon and lung cancer was conducted in five counties in New Jersey and involved 561 cases and 740 controls. A yearlong α-track detector measurement of radon was completed for ∼93% of all residences lived in at the time of interview (a total of 2063). While the odds ratios (ORs) for whole data were suggestive of an increased risk for exposures >75 Bq m -3 , these associations were not statistically significant. The adjusted excess OR (EOR) per 100 Bq m -3 was -0.13 (95% CI: -0.30 to 0.44) for males, 0.29 (95% CI: -0.12 to 1.70) for females and 0.05 (95% CI: -0.14 to 0.56) for all subjects combined. An analysis of radon effects by histological type of lung cancer showed that the OR was strongest for small/oat cell carcinomas in both males and females. There was no statistical heterogeneity of radon effects by demographic factors (age at disease occurrence, education level and type of respondent). Analysis by categories of smoking status, frequency or duration did not modify the risk estimates of radon on lung cancer. The findings of this study are consistent with an earlier population-based study of radon and lung cancer among New Jersey women, and with the North American pooling of case control radon seven studies, including the previous New Jersey study. Several uncertainties regarding radon measurements and assumptions of exposure history may have resulted in underestimation of a true exposure-response relationship. (authors)

  2. Regional recurrence of oropharyngeal cancer after definitive radiotherapy: a case control study

    International Nuclear Information System (INIS)

    Söderström, Karin; Nilsson, Per; Dalianis, Tina; Kjellén, Elisabeth; Zackrisson, Björn

    2015-01-01

    Elective treatment of lymph nodes in oropharyngeal cancer (OPC) has impact on both regional recurrences (RR) and risk of late side effects. This study was performed to quantify the dose-dependent impact on RR and overall survival (OS) in a prospectively collected cohort of OPC from the ARTSCAN study with emphasis on elective treatment. ARTSCAN is a previously published prospective, randomized, multicentre study of altered radiotherapy (RT) fractionation in head and neck cancer. In ARTSCAN the elective treatment volume for node positive OPC varied significantly between centres due to local treatment principles. All patients with OPC in complete response after primary treatment were eligible for the present case–control study. Cases were patients with RR during five years follow-up. Patients with no recurrence were eligible as controls. Four controls per case were matched according to T- and N-stage. Mean (D mean ) and median (D 50% ) dose for the lymph node level (LNL) of RR in the cases and the corresponding LNL in the controls were analysed with conditional logistic regression. OS was estimated with the Kaplan-Meier method and evaluated by multivariate Cox regression analysis. There was a dose-dependent risk reduction for D 50% in the interval that represented elective treatment (40–50 Gy) (OR = 0.18, p < 0.05) and a trend in the same dose interval for D mean (OR = 0.19, p = 0.07). OS rates at five years were 0.39 (0.24-0.65) for cases and 0.70 (0.62–0.81) for controls (p < 0.001). The Kaplan-Meier and the Cox regression analysis for cases categorised by delivered dose showed an inverse relationship between dose and survival. The cases with RR in a LNL outside planning target volume (PTV) (D mean < 40 Gy) had an OS rate comparable to that of all patients, and those with RR in a LNL in PTV elective (D mean 40–60 Gy) or PTV tumour (D mean >60 Gy) did significantly worse (p < 0.05). The same inverse relationship was also shown for a small subset of patient

  3. Case-control Studies on the Effectiveness of Breast Cancer Screening: Insights from the UK Age Trial.

    Science.gov (United States)

    van der Waal, Daniëlle; Broeders, Mireille J M; Verbeek, André L M; Duffy, Stephen W; Moss, Sue M

    2015-07-01

    Ongoing breast cancer screening programs can only be evaluated using observational study designs. Most studies have observed a reduction in breast cancer mortality, but design differences appear to have resulted in different estimates. Direct comparison of case-control and trial analyses gives more insight into this variation. Here, we performed case-control analyses within the randomized UK Age Trial. The Age Trial assessed the effect of screening on breast cancer mortality in women ages 40-49 years. In our approach, case subjects were defined as breast cancer deaths between trial entry (1991-1997) and 2004. Women were ages 39-41 years at entry. For every case subject, five control subjects were selected. All case subjects were included in analyses of screening invitation (356 case subjects, 1,780 controls), whereas analyses of attendance were restricted to women invited to screening (105 case subjects, 525 age-matched controls). Odds ratios (OR) were estimated with conditional logistic regression. We used and compared two methods to correct for self-selection bias. Screening invitation resulted in a breast cancer mortality reduction of 17% (95% confidence interval [CI]: -36%, +6%), similar to trial results. Different exposure definitions and self-selection adjustments influenced the observed breast cancer mortality reduction. Depending on the method, "ever screened" appeared to be associated with a small reduction (OR: 0.86, 95% CI: 0.40, 1.89) or no reduction (OR: 1.02, 95% CI: 0.48, 2.14) using the two methods of correction. Recent attendance resulted in an adjusted mortality reduction of 36% (95% CI: -69%, +31%) or 45% (95% CI: -71%, +5%). Observational studies, and particularly case-control studies, are an important monitoring tool for breast cancer screening programs. The focus should be on diminishing bias in observational studies and gaining a better understanding of the influence of study design on estimates of mortality reduction.

  4. Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

    OpenAIRE

    Cristina Lopez-del Burgo; Alfredo Gea; Jokin de Irala; Miguel A. Martínez-González; Jorge E. Chavarro; Estefania Toledo

    2015-01-01

    The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the ...

  5. Dietary calcium intake and the risk of colorectal cancer: a case control study

    OpenAIRE

    Han, Changwoo; Shin, Aesun; Lee, Jeonghee; Lee, Jeeyoo; Park, Ji Won; Oh, Jae Hwan; Kim, Jeongseon

    2015-01-01

    Background High intake of dietary calcium has been thought to be a protective factor against colorectal cancer. To explore the dose-response relationship in the associations between dietary calcium intake and colorectal cancer risk by cancer location, we conducted a case-control study among Korean population, whose dietary calcium intake levels are relatively low. Methods The colorectal cancer cases and controls were recruited from the National Cancer Center in Korea between August 2010 and A...

  6. Rationale and design of INTERSTROKE: a global case-control study of risk factors for stroke

    DEFF Research Database (Denmark)

    O'Donnell, M; Serpault, Damien Xavier; Diener, C

    2010-01-01

    with a first stroke within 72 h of hospital presentation in whom CT or MRI is performed. Proxy respondents are used for cases unable to communicate. Etiological and topographical stroke subtype is documented for all cases. Controls are hospital- and community-based, matched for gender, ethnicity and age (+/-5...... years). A questionnaire (cases and controls) is used to acquire information on known and proposed risk factors for stroke. Cardiovascular (e.g. blood pressure) and anthropometric (e.g. waist-to-hip ratio) measurements are obtained at the time of interview. Nonfasting blood samples and random urine......-income countries is inadequate, where a very large burden of stroke occurs. Accordingly, a similar epidemiological study is required for stroke, to inform effective population-based strategies to reduce the risk of stroke. Methods: INTERSTROKE is an international, multicenter case-control study. Cases are patients...

  7. A population-based case-control teratologic study of furazidine, a nitrofuran-derivative treatment during pregnancy.

    Science.gov (United States)

    Czeizel, A E; Rockenbauer, M; Sørensen, H T; Olsen, J

    2000-04-01

    To study human teratogenic potential of furazidine treatment during pregnancy. Pair analysis of cases with congenital abnormalities and matched population controls. The Hungarian Case-Control Surveillance of Congenital Abnormalities. 38,151 pregnant women who had newborn infants without any defects (population control group) and 22,865 pregnant women who had newborns or fetuses with congenital abnormalities between 1980 and 1996. In the case group, 157 (0.7%) and in the control group, 254 (0.7%) pregnant women were treated with furazidine. The case-control pair analysis did not indicate a teratogenic potential of furazidine use during the second to third months of gestation, i.e. in the critical period for major congenital abnormalities. Treatment with furazidine during pregnancy did not show teratogenic risk to the fetus.

  8. Fructose malabsorption in people with and without gout: A case-control study.

    Science.gov (United States)

    Batt, Caitlin; Fanning, Niamh; Drake, Jill; Frampton, Christopher; Gearry, Richard B; Stamp, Lisa K

    2017-10-01

    Higher fructose intake has been associated with hyperuricaemia and gout. Some individuals malabsorb fructose in the small intestine. The aims of this study were to determine the rate of fructose malabsorption and the effects of gout and fructose malabsorption on serum urate in people with and without gout. A total of 100 people with gout (cases) were age and gender matched with one control without gout. After a low fructose diet, fructose malabsorption was measured using a hydrogen and methane breath test with a 35g fructose load. In a subgroup of 35 cases and 35 controls, serum urate response to the fructose load over 240 minutes was measured. There was no significant difference in the rate of fructose malabsorption between cases and controls (48% vs. 52%; p = 0.67). Cases had a significantly lower mean (SEM) serum urate cumulative incremental concentration from baseline-240 minutes (iAUC 0-240 ) compared to controls 0.97 (0.56) vs. 4.78 (0.55); p gout. Allopurinol inhibits the increase in serum urate induced by a fructose load suggesting that people with gout receiving allopurinol may not need to restrict dietary intake of fructose. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Two-stage case-control association study of dopamine-related genes and migraine

    Directory of Open Access Journals (Sweden)

    Pardo Julio

    2009-09-01

    Full Text Available Abstract Background We previously reported risk haplotypes for two genes related with serotonin and dopamine metabolism: MAOA in migraine without aura and DDC in migraine with aura. Herein we investigate the contribution to migraine susceptibility of eight additional genes involved in dopamine neurotransmission. Methods We performed a two-stage case-control association study of 50 tag single nucleotide polymorphisms (SNPs, selected according to genetic coverage parameters. The first analysis consisted of 263 patients and 274 controls and the replication study was composed by 259 cases and 287 controls. All cases were diagnosed according to ICHD-II criteria, were Spanish Caucasian, and were sex-matched with control subjects. Results Single-marker analysis of the first population identified nominal associations of five genes with migraine. After applying a false discovery rate correction of 10%, the differences remained significant only for DRD2 (rs2283265 and TH (rs2070762. Multiple-marker analysis identified a five-marker T-C-G-C-G (rs12363125-rs2283265-rs2242592-rs1554929-rs2234689 risk haplotype in DRD2 and a two-marker A-C (rs6356-rs2070762 risk haplotype in TH that remained significant after correction by permutations. These results, however, were not replicated in the second independent cohort. Conclusion The present study does not support the involvement of the DRD1, DRD2, DRD3, DRD5, DBH, COMT, SLC6A3 and TH genes in the genetic predisposition to migraine in the Spanish population.

  10. Two case studies in river naturalization: planform migration and bank erosion control

    Science.gov (United States)

    Abad, J. D.; Guneralp, I.; Rhoads, B. L.; Garcia, M. H.

    2005-05-01

    A sound understanding of river planform evolution and bank erosion control, along with integration of expertise from several disciplines is required for the development of predictive models for river naturalization. Over the last few years, several methodologies have been presented for naturalization projects, from purely heuristic to more advanced methods. Since the time and space scales of concern in naturalization vary widely, there is a need for appropriate tools at a variety of time and space scales. This study presents two case studies at different scales. The first case study describes the prediction of river planform evolution for a remeandering project based on a simplified two-dimensional hydrodynamic model. The second case study describes the applicability of a Computational Fluid Dynamics (CFD) model for evaluating the effectiveness of bank-erosion control structures in individual meander bends. Understanding the hydrodynamic influence of control structures on flow through bends allows accurate prediction of depositional and erosional distribution patterns, resulting in better assessment on river planform stability, especially for the case of natural complex systems. The first case study introduces a mathematical model for evolution of meandering rivers that can be used in remeandering projects. In United States in particular, several rivers have been channelized in the past causing environmental and ecological problems. Following Newton's third law, "for every action, there is a reaction", naturalization techniques evolve as natural reactive solutions to channelization. This model (herein referred as RVR Meander) can be used as a stand-alone Windows application or as module in a Geographic Information System. The model was applied to the Poplar Creek re-meanderization project and used to evaluate re-meandering alternatives for an approximately 800-meter long reach of Poplar Creek that was straightened in 1938. The second case study describes a

  11. Esophageal cancer among Brazilian agricultural workers: case-control study based on death certificates.

    Science.gov (United States)

    Meyer, Armando; Alexandre, Pedro Celso Braga; Chrisman, Juliana de Rezende; Markowitz, Steven B; Koifman, Rosalina Jorge; Koifman, Sergio

    2011-03-01

    Several studies suggest that agricultural workers are at higher risk to develop and die by certain types of cancer. Esophageal cancer is not commonly listed among these types. However, some recent studies indicated that if there is an association between agricultural working and esophageal cancer, it s more likely to be observed among workers highly exposed to pesticides. In the present study, the magnitude of the association between agricultural working and esophageal cancer mortality was evaluated in a high pesticide use area in Brazil, through a death certificate-based case-control study. Cases were individuals from both genders, 30-59 years old, for whom basic cause of death was ascertained as cancer of the esophagus. For each case, one control was randomly selected from all possible controls for which the basic cause of death was ascertained as different from neoplasm and diseases of the digestive system. In addition, controls matched their cases by sex, age, year of death, and state of residence. Crude and adjusted odds ratios were then calculated to estimate the magnitude of the risk. Results showed that, in general, agricultural workers were at significantly higher risk to die by esophageal cancer, when compared to non-agricultural workers. Stratified analysis also revealed that the magnitude of such risk was slightly higher among illiterate agricultural workers, and simultaneous adjustment for several covariates showed that the risk was quantitatively higher among younger southern agricultural workers. These results suggest the esophageal cancer may be included among those types of cancer etiologically associated to agricultural working. Copyright © 2010 Elsevier GmbH. All rights reserved.

  12. A Case-Control Study of Risk Factors for Salivary Gland Cancer in Canada

    Directory of Open Access Journals (Sweden)

    Sai Yi Pan

    2017-01-01

    Full Text Available Aim. To assess the effect of various lifestyle risk factors on the risk of salivary gland cancer in Canada using data from a population-based case-control study. Methods. Data from a population-based case-control study of 132 incident cases of salivary gland cancer and 3076 population controls were collected through self-administered questionnaire and analysed using unconditional logistic regression. Results. Four or more servings/week of processed meat product was associated with an adjusted odds ratio (OR and corresponding 95% confidence interval (CI of 1.62 (1.02–2.58. Nonsignificantly increased ORs were also related to obesity, >7 drinks/week of alcohol consumption, and occupational exposure to radiation. Furthermore, nonsignificantly decreased ORs were found to be associated with high education level (>12 years (OR=0.65, high consumption of spinach/squash (OR=0.62 and all vegetables/vegetable juices (OR=0.75, and >30 sessions/month of recreational physical activity (OR=0.78. Conclusions. This study suggests positive associations with consumption of processed meat, smoking, obesity, alcohol drinking, and occupational exposure to radiation as well as negative associations with higher education, consumption of spinach/squash, and physical activity, which suggest a role of lifestyle factors in the etiology of salivary gland cancer. However, these findings were based on small number of cases and were nonsignificant. Further larger studies are warranted to confirm our findings.

  13. Publishing Single-Case Research Design Studies That Do Not Demonstrate Experimental Control

    Science.gov (United States)

    Tincani, Matt; Travers, Jason

    2018-01-01

    Demonstration of experimental control is considered a hallmark of high-quality single-case research design (SCRD). Studies that fail to demonstrate experimental control may not be published because researchers are unwilling to submit these papers for publication and journals are unlikely to publish negative results (i.e., the file drawer effect).…

  14. Effectiveness of reactive oral cholera vaccination in rural Haiti: a case-control study and bias-indicator analysis.

    Science.gov (United States)

    Ivers, Louise C; Hilaire, Isabelle J; Teng, Jessica E; Almazor, Charles P; Jerome, J Gregory; Ternier, Ralph; Boncy, Jacques; Buteau, Josiane; Murray, Megan B; Harris, Jason B; Franke, Molly F

    2015-03-01

    Between April and June, 2012, a reactive cholera vaccination campaign was done in Haiti with an oral inactivated bivalent whole-cell vaccine. We aimed to assess the effectiveness of the vaccine in a case-control study and to assess the likelihood of bias in that study in a bias-indicator study. Residents of Bocozel or Grand Saline who were eligible for the vaccination campaign (ie, age ≥12 months, not pregnant, and living in the region at the time of the vaccine campaign) were included. In the primary case-control study, cases had acute watery diarrhoea, sought treatment at one of three participating cholera treatment units, and had a stool sample positive for cholera by culture. For each case, four control individuals who did not seek treatment for acute watery diarrhoea were matched by location of residence, enrolment time (within 2 weeks of the case), and age (1-4 years, 5-15 years, and >15 years). Cases in the bias-indicator study were individuals with acute watery diarrhoea with a negative stool sample for cholera. Controls were selected in the same manner as in the primary case-control study. Trained staff used standard laboratory procedures to do rapid tests and stool cultures from study cases. Participants were interviewed to collect data on sociodemographic characteristics, risk factors for cholera, and self-reported vaccination. Data were analysed by conditional logistic regression, adjusting for matching factors. From Oct 24, 2012, to March 9, 2014, 114 eligible individuals presented with acute watery diarrhoea and were enrolled, 25 of whom were subsequently excluded. 47 participants were analysed as cases in the vaccine effectiveness case-control study and 42 as cases in the bias-indicator study. 33 (70%) of 47 cholera cases self-reported vaccination versus 167 (89%) of 188 controls (vaccine effectiveness 63%, 95% CI 8-85). 27 (57%) of 47 cases had certified vaccination versus 147 (78%) of 188 controls (vaccine effectiveness 58%, 13-80). Neither self

  15. Medical records documentation of constipation preceding Parkinson disease: A case-control study.

    Science.gov (United States)

    Savica, R; Carlin, J M; Grossardt, B R; Bower, J H; Ahlskog, J E; Maraganore, D M; Bharucha, A E; Rocca, W A

    2009-11-24

    Parkinson disease (PD) may affect the autonomic nervous system and may cause constipation; however, few studies have explored constipation preceding the motor onset of PD. We investigated constipation preceding PD using a case-control study design in a population-based sample. Using the medical records-linkage system of the Rochester Epidemiology Project, we identified 196 subjects who developed PD in Olmsted County, MN, from 1976 through 1995. Each incident case was matched by age (+/-1 year) and sex to a general population control. We reviewed the complete medical records of cases and controls in the medical records-linkage system to ascertain the occurrence of constipation preceding the onset of PD (or index year). Constipation preceding PD or the index year was more common in cases than in controls (odds ratio [OR] 2.48; 95% confidence interval [CI] 1.49 to 4.11; p = 0.0005). This association remained significant after adjusting for smoking and coffee consumption (ever vs never), and after excluding constipation possibly induced by drugs. In addition, the association remained significant in analyses restricted to constipation documented 20 or more years before the onset of motor symptoms of PD. Although the association was stronger in women than in men and in patients with PD with rest tremor compared with patients with PD without rest tremor, these differences were not significant. Our findings suggest that constipation occurring as early as 20 or more years before the onset of motor symptoms is associated with an increased risk of Parkinson disease.

  16. Epidural analgesia in labour and neonatal respiratory distress: a case-control study.

    Science.gov (United States)

    Kumar, Manoj; Chandra, Sue; Ijaz, Zainab; Senthilselvan, Ambikaipakan

    2014-03-01

    Epidural analgesia is the commonest mode for providing pain relief in labour, with a combination of bupivacaine and fentanyl most often used in practice. To test whether late-preterm and term neonates exposed to opioids in epidural analgesia in labour are more likely to develop respiratory distress in the immediate neonatal period. A case-control study was conducted of singleton infants born during January 2006 to December 2010. Cases were neonates ≥34 weeks gestation, who developed respiratory distress within 24 h of life requiring supplemental oxygen ≥2 h and/or positive pressure ventilation in the neonatal intensive care unit. Controls were gestation and site-matched neonates who did not develop any respiratory distress within the same period. The information on exposure to epidural analgesia and on potential confounding variables was obtained from the standardised delivery record, routinely filled out on all women admitted to the labour wards. In our study, 206 cases and 206 matched controls were enrolled. Exposure to epidural analgesia was present in 146 (70.9%) cases as compared with 131 (63.6%) of the controls. The association between exposure to epidural analgesia and respiratory distress in neonates was statistically significant upon adjustment for all potential confounders (adjusted OR: 1.75, 95% CI 1.03 to 2.99; p = 0.04). When data was separately analysed for term and late-preterm infants, the results were consistent across these subpopulations, showing no interaction effect. Late-preterm and term infants exposed to maternal epidural analgesia in labour are more likely to develop respiratory distress in the immediate neonatal period.

  17. Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.

    Science.gov (United States)

    Kobeissi, Loulou; Inhorn, Marcia C

    2007-01-01

    The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.

  18. A population-based case-control teratologic study of ampicillin treatment during pregnancy

    DEFF Research Database (Denmark)

    Czeizel, A.E.; Rockenbauer, M.; Sørensen, Henrik Toft

    2001-01-01

    Objective: This was a study of the association between ampicillin treatment during pregnancy and prevalence of different congenital abnormalities. Study Design: The paired analysis of case patients with congenital abnormalities and matched population control subjects was performed in the populati...

  19. Effectiveness of oral polio vaccination against paralytic poliomyelitis: a matched case-control study in Somalia.

    Science.gov (United States)

    Mahamud, Abdirahman; Kamadjeu, Raoul; Webeck, Jenna; Mbaeyi, Chukwuma; Baranyikwa, Marie Therese; Birungi, Julianne; Nurbile, Yassin; Ehrhardt, Derek; Shukla, Hemant; Chatterjee, Anirban; Mulugeta, Abraham

    2014-11-01

    After the last case of type 1 wild poliovirus (WPV1) was reported in 2007, Somalia experienced another outbreak of WPV1 (189 cases) in 2013. We conducted a retrospective, matched case-control study to evaluate the vaccine effectiveness (VE) of oral polio vaccine (OPV). We retrieved information from the Somalia Surveillance Database. A case was defined as any case of acute flaccid paralysis (AFP) with virological confirmation of WPV1. We selected two groups of controls for each case: non-polio AFP cases ("NPAFP controls") matched to WPV1 cases by age, date of onset of paralysis and region; and asymptomatic "neighborhood controls," matched by age. Using conditional logistic regression, we estimated the VE of OPV as (1-odds ratio)×100. We matched 99 WPV cases with 99 NPAFP controls and 134 WPV1 cases with 268 neighborhood controls. Using NPAFP controls, the overall VE was 70% (95% confidence interval [CI], 37-86), 59% (2-83) among 1-3 dose recipients, 77% (95% CI, 46-91) among ≥4 dose recipients. In neighborhood controls, the overall VE was 95% (95% CI, 84-98), 92% (72-98) among 1-3 dose recipients, and 97% (89-99) among ≥4 dose recipients. When the analysis was limited to cases and controls ≤24 months old, the overall VE in NPAFP and neighborhood controls was 95% (95% CI, 65-99) and 97% (95% CI, 76-100), respectively. Among individuals who were fully vaccinated with OPV, vaccination was effective at preventing WPV1 in Somalia. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  20. A Case-control Study of Diphtheria in the High Incidence City of Hyderabad, India.

    Science.gov (United States)

    Allam, Ramesh Reddy; Uthappa, Chengappa Kechamada; Duerst, Rebecca; Sorley, Evan; Udaragudi, Prasada Rao; Kampa, Shankar; Dworkin, Mark S

    2016-03-01

    India accounts for approximately 72% of reported diphtheria cases globally, the majority of which occur in the state of Andhra Pradesh. The aim of this study is to better understand lack of knowledge on diphtheria vaccination and to determine factors associated with diphtheria and low knowledge and negative attitudes. We performed a 1:1 case-control study of hospitalized diphtheria cases in Hyderabad. Eligible case patients were 10 years of age or older, resided within the city of Hyderabad and were diagnosed with diphtheria per the case definition. Patients admitted to the hospital for nonrespiratory communicable diseases and residing in the same geographic region as that of cases were eligible for enrolment as controls : There were no statistical differences in disease outcome by gender, education, economic status and mean room per person sleeping in the house in case and control subjects. Not having heard of diphtheria (adjusted odds ratio: 3.56; 95% confidence intervals: 1.58-8.04] and not believing that vaccines can prevent people from getting diseases (adjusted odds ratio: 3.99; 95% confidence intervals: 1.18-13.45) remained significantly associated with diphtheria on multivariate analysis. To reduce the burden of diphtheria in India, further efforts to educate the public about diphtheria should be considered.

  1. Psychosocial and Psychiatric Factors Associated with Adolescent Suicide: A Case-Control Psychological Autopsy Study

    Science.gov (United States)

    Portzky, Gwendolyn; Audenaert, Kurt; van Heeringen, Kees

    2009-01-01

    This study aimed at the investigation of psychosocial and psychiatric risk factors of adolescent suicide by means of a case-control psychological autopsy study. Relatives and other informants of 19 suicide victims and 19 matched psychiatric controls were interviewed by means of a semi-structured interview schedule. Psychiatric controls included…

  2. Environmental risk factors contributing to traffic accidents in children: a case-control study.

    Science.gov (United States)

    Jamshidi, Ensiyeh; Moradi, Ali; Majdzadeh, Reza

    2017-09-01

    The aim of this study is to identify environmental risk factors related to road accidents in children of Tehran. This case-control study was performed in 2013. The cases were injured pedestrians aged 5-15 who were admitted to major hospitals supervised by Tehran University of Medical Sciences. The sample size for the cases was 273 and for the control group was 546. For the completeness of the clusters, 7 extra persons in case (total = 280) and 14 persons (total = 560) in control group were included. The interference of confounding variables assessed through forward conditional logistic regression. Result shows occurrence of traffic accidents was significantly associate with the width of the alleys or (traffic congestion (OR = 4.1, 95% CI: 2.6-6.4), traffic speed (OR = 2.1, 95% CI: 1.3-3.2) and existence of pedestrian bridges(OR = 4.2, 95% CI: 2.6-6.8). In the light of the important role of environmental factors in the occurrence of child traffic accidents, alleviating structural risk factors in addition to education and enforcement need more systematic efforts and planning by policymakers and urban planners to attain pedestrian safety goals.

  3. Shigellosis Outbreak in Al Batinah South Governorate, Oman; Case-control study

    Directory of Open Access Journals (Sweden)

    Idris Abaidani

    2015-08-01

    Full Text Available Objectives: An outbreak of acute gastroenteritis due to Shigella flexneri occurred in August 2012 in the catchment area of the Wadi Sahtan Health Center in Rustaq, Al Batinah South Governorate, Oman. The aim of this study was to discover possible causes of this outbreak in the villages of Fassa, Rogh and Amk and to measure the risk of exposure among cases and controls. Methods: A case-control study was conducted in September 2012 in Fassa, Rogh and Amk. All households in the three villages were interviewed. Case and control households were compared to determine possible exposure avenues, including place of residence, source of drinking water, hand hygiene levels and practices related to drinking water, food preparation and environmental sanitation. Results: Residing in Fassa (P <0.0001; odds ratio [OR] = 4.86, 95% confidence interval [CI] = 2.22–10.63 and average hand hygiene practices (P = 0.008; OR = 13.97, 95% CI = 1.58–123.36 were associated with an increased risk of contracting shigellosis. No significant differences were found with regards to the other exposure avenues. Conclusion: This was the first study conducted in Oman regarding an outbreak of shigellosis in a community setting. The only variables that significantly impacted the risk of acute gastroenteritis were residing in Fassa and average hand hygiene practices. The source of the outbreak could not be identified. However, septic tank sanitation and water and food consumption practices were not satisfactory in the studied villages. These need to be addressed to prevent similar outbreaks of acute gastroenteritis in this region in the future.

  4. Intra- versus retroplacental hematomas: a retrospective case-control study on pregnancy outcomes.

    Science.gov (United States)

    Ott, Johannes; Pecnik, Philipp; Promberger, Regina; Pils, Sophie; Binder, Julia; Chalubinski, Kinga M

    2017-10-26

    Intrauterine hematomas are a common pregnancy complication. The literature lacks studies about outcomes based on hematoma localization. Thus, we aimed to compare pregnancies complicated by an intraplacental hematoma to cases with a retroplacental hematoma and to a control group. In a retrospective case-control study, 32 women with an intraplacental hematoma, 199 women with a retroplacental hematoma, and a control group consisting of 113 age-matched women with no signs of placental abnormalities were included. Main outcome measures were pregnancy complications. Second-trimester miscarriage was most common in the intraplacental hematoma group (9.4%), followed by women with a retroplacental hematoma (4.2%), and controls (0%; p = 0.007). The intraplacental hematoma group revealed the highest rates for placental insufficiency, intrauterine growth retardation, premature preterm rupture of membranes, preterm labor, preterm delivery hematoma group. When tested in multivariate models, intraplacental hematomas were independent predictors for placental insufficiency (ß = 4.19, p hematoma (p = 0.042). Intra- and retroplacental hematomas have different risk profiles for the affected pregnancy and act as independent risk factors.

  5. Leptospira Exposure and Patients with Liver Diseases: A Case-Control Seroprevalence Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Ramos-Nevárez, Agar; Margarita Cerrillo-Soto, Sandra; Alberto Guido-Arreola, Carlos

    2016-01-01

    The seroepidemiology of Leptospira infection in patients suffering from liver disease has been poorly studied. Information about risk factors associated with infection in liver disease patients may help in the optimal planning of preventive measures. We sought to determine the association of Leptospira IgG seroprevalence and patients with liver diseases, and to determine the characteristics of the patients with Leptospira exposure. We performed a case-control study of 75 patients suffering from liver diseases and 150 age- and gender-matched control subjects. Diagnoses of liver disease included liver cirrhosis, steatosis, chronic hepatitis, acute hepatitis, and amoebic liver abscess. Sera of participants were analyzed for the presence of anti- Leptospira IgG antibodies using a commercially available enzyme immunoassay. Anti-Leptospira IgG antibodies were found in 17 (22.7%) of 75 patients and in 15 (10.0%) of 150 control subjects (OR = 2.32; 95% CI: 1.09-4.94; P=0.03). This is the first age- and gender-matched case control study about Leptospira seroprevalence in patients with liver diseases. Results indicate that Leptospira infection is associated with chronic and acute liver diseases. Results warrants for additional studies on the role of Leptospira exposure in chronic liver disease. PMID:27493589

  6. Placental histology in spontaneous and indicated preterm birth: A case control study

    NARCIS (Netherlands)

    Nijman, Tobias A. J.; van Vliet, Elvira O. G.; Benders, Manon J. N.; Mol, Ben Willem J.; Franx, Arie; Nikkels, Peter G. J.; Oudijk, Martijn A.

    2016-01-01

    Placental pathology is an important contributor in preterm birth, both spontaneous and indicated. The aim of this study was to describe and compare placental histological features of spontaneous preterm birth versus indicated preterm birth. A case control study was performed at the University

  7. A case-control study of the association between ulcerative colitis and hyperthyroidism in an Asian population.

    Science.gov (United States)

    Tsai, Ming-Chieh; Lin, Herng-Ching; Lee, Cha-Ze

    2017-06-01

    Ulcerative colitis (UC) is a chronic relapsing inflammatory disease with significant clinical diversity. However, the aetiology, pathogenesis and optimal treatment of UC remain unclear. The purpose of this case-control study was to investigate the association between previously diagnosed hyperthyroidism and UC using a large population-based data set in Taiwan. The data for this population-based case-control study were retrieved from the Taiwan Longitudinal Health Insurance Database 2005. We included 2709 patients with UC as cases and 8127 sex- and age-matched patients without UC as controls. A conditional logistic regression analysis was conducted to compute the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between UC and prior hyperthyroidism. We found that, in total, 327 of the 10 836 sampled patients (3.02%) had previously been diagnosed with hyperthyroidism. There was a higher proportion of prior hyperthyroidism among cases than controls (4.10% vs 2.66%, Phyperthyroidism was 1.57 (95% CI=1.24-1.98) compared to controls. Similarly, after adjusting for monthly income, geographic location and urbanization level, cases were still more likely to have previously been diagnosed with hyperthyroidism than controls (OR=1.61, 95% CI=1.27-2.05). Furthermore, we analysed the ORs of prior hyperthyroidism between cases and controls according to age group. We found that of the youngest group of sampled patients (18-39 years), cases had the greatest adjusted OR for having previously been diagnosed with hyperthyroidism than controls (OR=1.98, 95% CI=1.04-3.79). This study demonstrated an association between UC and hyperthyroidism. © 2017 John Wiley & Sons Ltd.

  8. A cholera outbreak in Alborz Province, Iran: a matched case-control study.

    Science.gov (United States)

    Moradi, Ghobad; Rasouli, Mohammad Aziz; Mohammadi, Parvin; Elahi, Elham; Barati, Hojatollah

    2016-01-01

    A total of 229 confirmed cholera cases were reported in Alborz Province during an outbreak that lasted from June 2011 to August 2011. This study aimed to identify potential sources of transmission in order to determine suitable interventions in similar outbreaks. In other words, the lessons learned from this retrospective study can be utilized to manage future similar outbreaks. An age-matched and sex-matched case-control study was conducted during the outbreak. For each case, two control subjects were selected from the neighborhood. A case of cholera was defined as a bacteriologically confirmed case with signs and symptoms of cholera. This study was conducted from June 14, 2011 through August 23, 2011. The data were analyzed by calculating odds ratios (ORs) using the logistic regression method. In this outbreak, 229 confirmed cholera cases were diagnosed. The following risk factors were found to be associated with cholera: consumption of unrefrigerated leftover food (OR, 3.05; 95% confidence interval [CI], 1.72 to 5.41), consumption of vegetables and fruits in the previous three days (OR, 2.75; 95% CI, 1.95 to 3.89), and a history of traveling in the previous five days (OR, 5.31; 95% CI, 2.21 to 9.72). Consumption of vegetables and fruits has remained an unresolved risk factor in cholera outbreaks in Iran in recent years. In order to reduce the risk of cholera, sanitary standards for fruits and vegetables should be observed at all points from production to consumption, the population should be educated regarding hygienic food storage during outbreaks, and sanitary standards should be maintained when traveling during cholera outbreaks.

  9. A cholera outbreak in Alborz Province, Iran: a matched case-control study

    Directory of Open Access Journals (Sweden)

    Ghobad Moradi

    2016-05-01

    Full Text Available OBJECTIVES: A total of 229 confirmed cholera cases were reported in Alborz Province during an outbreak that lasted from June 2011 to August 2011. This study aimed to identify potential sources of transmission in order to determine suitable interventions in similar outbreaks. In other words, the lessons learned from this retrospective study can be utilized to manage future similar outbreaks. METHODS: An age-matched and sex-matched case-control study was conducted during the outbreak. For each case, two control subjects were selected from the neighborhood. A case of cholera was defined as a bacteriologically confirmed case with signs and symptoms of cholera. This study was conducted from June 14, 2011 through August 23, 2011. The data were analyzed by calculating odds ratios (ORs using the logistic regression method. RESULTS: In this outbreak, 229 confirmed cholera cases were diagnosed. The following risk factors were found to be associated with cholera: consumption of unrefrigerated leftover food (OR, 3.05; 95% confidence interval [CI], 1.72 to 5.41, consumption of vegetables and fruits in the previous three days (OR, 2.75; 95% CI, 1.95 to 3.89, and a history of traveling in the previous five days (OR, 5.31; 95% CI, 2.21 to 9.72. CONCLUSIONS: Consumption of vegetables and fruits has remained an unresolved risk factor in cholera outbreaks in Iran in recent years. In order to reduce the risk of cholera, sanitary standards for fruits and vegetables should be observed at all points from production to consumption, the population should be educated regarding hygienic food storage during outbreaks, and sanitary standards should be maintained when traveling during cholera outbreaks.

  10. Method for mapping population-based case-control studies: an application using generalized additive models

    Directory of Open Access Journals (Sweden)

    Aschengrau Ann

    2006-06-01

    Full Text Available Abstract Background Mapping spatial distributions of disease occurrence and risk can serve as a useful tool for identifying exposures of public health concern. Disease registry data are often mapped by town or county of diagnosis and contain limited data on covariates. These maps often possess poor spatial resolution, the potential for spatial confounding, and the inability to consider latency. Population-based case-control studies can provide detailed information on residential history and covariates. Results Generalized additive models (GAMs provide a useful framework for mapping point-based epidemiologic data. Smoothing on location while controlling for covariates produces adjusted maps. We generate maps of odds ratios using the entire study area as a reference. We smooth using a locally weighted regression smoother (loess, a method that combines the advantages of nearest neighbor and kernel methods. We choose an optimal degree of smoothing by minimizing Akaike's Information Criterion. We use a deviance-based test to assess the overall importance of location in the model and pointwise permutation tests to locate regions of significantly increased or decreased risk. The method is illustrated with synthetic data and data from a population-based case-control study, using S-Plus and ArcView software. Conclusion Our goal is to develop practical methods for mapping population-based case-control and cohort studies. The method described here performs well for our synthetic data, reproducing important features of the data and adequately controlling the covariate. When applied to the population-based case-control data set, the method suggests spatial confounding and identifies statistically significant areas of increased and decreased odds ratios.

  11. Parental consanguinity and susceptibility to drug abuse among offspring, a case-control study.

    Science.gov (United States)

    Saadat, Mostafa; Vakili-Ghartavol, Roghayyeh

    2010-11-30

    Consanguineous marriage is the union of individuals having at least one common ancestor. It is well established that consanguinity is a potential risk factor for many adverse health outcome of offspring. In the present case-control study we tested the hypothesis of an association between parental consanguinity marriages and risk of offspring substance abuse. The study was performed in Shiraz (Fars province, Iran). Here 156 male drug abusers (case group) and 264 randomly selected healthy blood donors, matched for age and gender as control group, were included in the study. The prevalence of parental consanguineous marriages in the studied sample was 39.1 and 28.0% among cases and controls, respectively. The difference was statistically significant. The substance abusers were more smokers and drinkers compared with the control group. There was significant negative linear trend between drug abuse and level of education. The participants stratified using drinking habits and then the analysis was carried out separately for drinker and non-drinker subjects. Among drinkers, neither before nor after adjusting for smoking status and educational level, parental consanguinity did not show association with risk of substance abuse. Among non-drinkers, after adjusting for smoking status and educational level, parental consanguineous marriage was significantly associated with increased risk of substance abuse. Our study supports a significant relationship between parental consanguinity and drug abuse among non-drinker subjects. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Risk factors associated with hantavirosis fatality: a regional analysis from a case-control study in Brazil

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    Maria Cristina Antunes Willemann

    2014-01-01

    Full Text Available Introduction: In Brazil, hantavirus cardiopulmonary syndrome (HCPS has a high lethality rate that varies by region. This study aimed to identify the risk factors associated with fatal hantavirosis. Methods: This study was a case-control study that included all laboratory confirmed cases of hantavirosis. The cases were stratified by the different Brazilian regions using data from the Notifiable Diseases Information System. “Cases” were patients who progressed to death, whereas “controls” were patients who were cured. The odds ratio (OR and the adjusted OR were calculated. Results: Overall, 158 cases and 281 controls were included in this study. In the Midwest region, the cases were 60% less likely to present with flank pain, and the time between the beginning of symptoms and death was shorter than the time between the beginning of symptoms and a cure. In the Southeast region, the cases were 60% less likely to present with thrombocytopenia or reside in rural areas compared to those who progressed to a cure. Additionally, the cases sought medical assistance, notification and investigation more quickly than the controls. In the Southern region, the cases that died were 70% less likely to be male compared to the controls. Conclusions: HCPS manifests with nonspecific symptoms, and there are few published studies related to the condition, so determining a patient's therapeutic strategy is difficult. This study presents findings from different Brazilian regions and highlights the need for further investigations to improve comprehension about regional risk factors associated with hantavirosis and to reduce morbimortality.

  13. Splenectomy Correlates With Increased Risk of Acute Pancreatitis: A Case-Control Study in Taiwan

    Science.gov (United States)

    Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu

    2016-01-01

    Objective The objective of the study was to investigate the association between splenectomy and acute pancreatitis. Methods We conducted a case-control study using the database of the Taiwan National Health Insurance Program. We included 7666 subjects aged 20–84 years with first-time acute pancreatitis during the period of 1998–2011 as cases and 30 664 randomly selected subjects without acute pancreatitis as controls. Both cases and controls were matched for sex, age, and index year of acute pancreatitis diagnosis. The association of acute pancreatitis with splenectomy was examined using a multivariable unconditional logistic regression model and reported as an odds ratio and its 95% confidence interval (CI). Results After adjustment for covariables, the adjusted odds ratio of acute pancreatitis was 2.90 for subjects with splenectomy (95% CI, 1.39–6.05) compared with subjects without splenectomy. Conclusions Splenectomy is associated with acute pancreatitis. Further studies are necessary to clarify the underlying mechanism. PMID:27087607

  14. Welding and lung cancer in a pooled analysis of case-control studies.

    Science.gov (United States)

    Kendzia, Benjamin; Behrens, Thomas; Jöckel, Karl-Heinz; Siemiatycki, Jack; Kromhout, Hans; Vermeulen, Roel; Peters, Susan; Van Gelder, Rainer; Olsson, Ann; Brüske, Irene; Wichmann, H-Erich; Stücker, Isabelle; Guida, Florence; Tardón, Adonina; Merletti, Franco; Mirabelli, Dario; Richiardi, Lorenzo; Pohlabeln, Hermann; Ahrens, Wolfgang; Landi, Maria Teresa; Caporaso, Neil; Consonni, Dario; Zaridze, David; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Gustavsson, Per; Marcus, Michael; Fabianova, Eleonora; 't Mannetje, Andrea; Pearce, Neil; Tse, Lap Ah; Yu, Ignatius Tak-Sun; Rudnai, Peter; Bencko, Vladimir; Janout, Vladimir; Mates, Dana; Foretova, Lenka; Forastiere, Francesco; McLaughlin, John; Demers, Paul; Bueno-de-Mesquita, Bas; Boffetta, Paolo; Schüz, Joachim; Straif, Kurt; Pesch, Beate; Brüning, Thomas

    2013-11-15

    Several epidemiologic studies have indicated an increased risk of lung cancer among welders. We used the SYNERGY project database to assess welding as a risk factor for developing lung cancer. The database includes data on 15,483 male lung cancer cases and 18,388 male controls from 16 studies in Europe, Canada, China, and New Zealand conducted between 1985 and 2010. Odds ratios and 95% confidence intervals between regular or occasional welding and lung cancer were estimated, with adjustment for smoking, age, study center, and employment in other occupations associated with lung cancer risk. Overall, 568 cases and 427 controls had ever worked as welders and had an odds ratio of developing lung cancer of 1.44 (95% confidence interval: 1.25, 1.67) with the odds ratio increasing for longer duration of welding. In never and light smokers, the odds ratio was 1.96 (95% confidence interval: 1.37, 2.79). The odds ratios were somewhat higher for squamous and small cell lung cancers than for adenocarcinoma. Another 1,994 cases and 1,930 controls had ever worked in occupations with occasional welding. Work in any of these occupations was associated with some elevation of risk, though not as much as observed in regular welders. Our findings lend further support to the hypothesis that welding is associated with an increased risk of lung cancer.

  15. Factors associated with suicide: Case-control study in South Tyrol.

    Science.gov (United States)

    Giupponi, Giancarlo; Innamorati, Marco; Baldessarini, Ross J; De Leo, Diego; de Giovannelli, Francesca; Pycha, Roger; Conca, Andreas; Girardi, Paolo; Pompili, Maurizio

    2018-01-01

    As suicide is related to many factors in addition to psychiatric illness, broad and comprehensive risk-assessment for risk of suicide is required. This study aimed to differentiate nondiagnostic risk factors among suicides versus comparable psychiatric patients without suicidal behavior. We carried out a pilot, case-control comparison of 131 cases of suicide in South Tyrol matched for age and sex with 131 psychiatric controls, using psychological autopsy methods to evaluate differences in clinically assessed demographic, social, and clinical factors, using bivariate conditional Odds Risk comparisons followed by conditional regression modeling controlled for ethnicity. Based on multivariable conditional regression modeling, suicides were significantly more likely to have experienced risk factors, ranking as: [a] family history of suicide or attempt≥[b] recent interpersonal stressors≥[c] childhood traumatic events≥[d] lack of recent clinician contacts≥[e] previous suicide attempt≥[f] non-Italian ethnicity, but did not differ in education, marital status, living situation, or employment, nor by psychiatric or substance-abuse diagnoses. Both recent and early factors were associated with suicide, including lack of recent clinical care, non-Italian cultural subgroup-membership, familial suicidal behavior, and recent interpersonal distress. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. A case-control study estimating accident risk for alcohol, medicines and illegal drugs.

    Directory of Open Access Journals (Sweden)

    Kim Paula Colette Kuypers

    Full Text Available The aim of the present study was to assess the risk of having a traffic accident after using alcohol, single drugs, or a combination, and to determine the concentrations at which this risk is significantly increased.A population-based case-control study was carried out, collecting whole blood samples of both cases and controls, in which a number of drugs were detected. The risk of having an accident when under the influence of drugs was estimated using logistic regression adjusting for gender, age and time period of accident (cases/sampling (controls. The main outcome measures were odds ratio (OR for accident risk associated with single and multiple drug use. In total, 337 cases (negative: 176; positive: 161 and 2726 controls (negative: 2425; positive: 301 were included in the study.Main findings were that 1 alcohol in general (all the concentrations together caused an elevated crash risk; 2 cannabis in general also caused an increase in accident risk; at a cut-off of 2 ng/mL THC the risk of having an accident was four times the risk associated with the lowest THC concentrations; 3 when ranking the adjusted OR from lowest to highest risk, alcohol alone or in combination with other drugs was related to a very elevated crash risk, with the highest risk for stimulants combined with sedatives.The study demonstrated a concentration-dependent crash risk for THC positive drivers. Alcohol and alcohol-drug combinations are by far the most prevalent substances in drivers and subsequently pose the largest risk in traffic, both in terms of risk and scope.

  17. Therapeutic radiation and hyperparathyroidism. A case-control study in Rochester, Minn

    International Nuclear Information System (INIS)

    Beard, C.M.; Heath, H. III; O'Fallon, W.M.; Anderson, J.A.; Earle, J.D.; Melton, L.J. III

    1989-01-01

    A case-control study was conducted among residents of Rochester, Minn, to assess the influence of prior therapeutic radiation on the risk of primary hyperparathyroidism. Fifty-one cases of surgically proven primary hyperparathyroidism diagnosed from 1975 through 1983 were each matched by age and gender to two control subjects, with radiation exposure documented through preexisting medical records. The overall odds ratio for any prior therapeutic radiation therapy was 1.9 (95% confidence interval, 0.9 to 4.4) and it was 2.3 (95% confidence interval, 0.9 to 5.7) when limited to those with prior head and neck radiation. Among women, the figures were 2.9 (95% confidence interval, 1.1 to 7.5) for any prior therapeutic radiation and 3.4 (95% confidence interval, 1.2 to 10.2) for head and neck exposure. This study confirms the association between primary hyperparathyroidism and prior therapeutic radiation exposure, at least for women in this population

  18. Ultrasound analysis of mental artery flow in elderly patients: a case-control study.

    Science.gov (United States)

    Baladi, Marina G; Tucunduva Neto, Raul R C M; Cortes, Arthur R G; Aoki, Eduardo M; Arita, Emiko S; Freitas, Claudio F

    2015-01-01

    Mental artery flow decreases with age and may have an aetiological role in alveolar ridge atrophy. The aim of this study was to identify factors associated with alterations of mental artery flow, assessed by ultrasonography. This case-control study was conducted on elderly patients (aged above 60 years) at the beginning of dental treatment. Intraoral B-mode Doppler ultrasonography was used to assess mental artery flow. The cases were defined as patients with a weak/absent ultrasound signal, whereas the controls presented a strong ultrasound signal. Demographics and radiographic findings (low bone mineral density on dual-energy X-ray absorptiometry and mandibular cortical index on panoramic radiographs) were analysed as risk factors for weak/absent ultrasound signal and were calculated as adjusted odds ratios (AORs) with 95% confidence intervals (CIs) using conditional logistic regression. In addition, the Student's t-test was used to compare the mean alveolar bone height of the analysed groups. A p-value <0.05 was considered statistically significant. A total of 30 ultrasound examinations (12 cases and 18 controls) were analysed. A weak/absent mental artery pulse strength was significantly associated with edentulism (AOR = 3.67; 95% CI = 0.86-15.63; p = 0.046). In addition, there was a significant difference in alveolar bone height between edentulous cases and controls (p = 0.036). Within the limitations of this study, the present results indicate that edentulism is associated with diminished mental artery flow, which, in turn, affects alveolar bone height.

  19. Risk factors for pulmonary tuberculosis: a clinic-based case control study in The Gambia

    Directory of Open Access Journals (Sweden)

    Adegbola Richard A

    2006-06-01

    Full Text Available Abstract Background The tuberculosis (TB epidemic in Africa is on the rise, even in low-HIV prevalence settings. Few studies have attempted to identify possible reasons for this. We aimed to identify risk factors for pulmonary tuberculosis in those attending a general outpatients clinic in The Gambia, a sub-Saharan African country with relatively low HIV prevalence in the community and in TB patients. Methods We conducted a case control study at the Medical Research Council Outpatients' clinic in The Gambia. Pulmonary TB cases were at least 15 years old, controls were age and sex matched clinic attendees. Participants were interviewed using a structured questionnaire. Results 100 sputum smear positive TB cases and 200 clinic controls were recruited. HIV prevalence was 6.1% in cases and 3.3% in controls. Multivariable assessment of host factors showed that risk of TB was increased among the Jola ethnic group and smokers, and decreased in those in a professional occupation. Assessment of environmental factors showed an increased risk with household crowding, history of household exposure to a known TB case, and absence of a ceiling in the house. In a combined multivariable host-environment model, the risk of TB increased with crowding, exposure to a known TB case, as well as amongst the Jola ethnic group. Conclusion In The Gambia, household crowding and past household exposure to a known TB case are the standout risk factors for TB disease. Further research is needed to identify why risk of TB seems to differ according to ethnicity.

  20. Vitamin D and Fracture Risk in Early Childhood: A Case-Control Study.

    Science.gov (United States)

    Anderson, Laura N; Heong, Sze Wing; Chen, Yang; Thorpe, Kevin E; Adeli, Khosrow; Howard, Andrew; Sochett, Etienne; Birken, Catherine S; Parkin, Patricia C; Maguire, Jonathon L

    2017-06-15

    The objective of this study was to evaluate the association of vitamin D intake and serum levels with fracture risk in children under 6 years of age. A case-control study was conducted in Toronto, Ontario, Canada. Cases were recruited from the fracture clinic at the Hospital for Sick Children, and matched controls were obtained from the TARGet Kids! primary-care research network. Controls were matched to cases on age, sex, height, and season. Fracture risk was estimated from conditional logistic regression, with adjustment for skin type, fracture history, waist circumference, outdoor free play, neighborhood income, soda consumption, and child's birth weight. A total of 206 cases were recruited during May 2009-April 2013 and matched to 343 controls. Serum 25-hydroxyvitamin D concentration (per 10-nmol/L increment: adjusted odds ratio (aOR) = 0.95, 95% confidence interval (CI): 0.88, 1.03) and intake of cow's milk (2 cups/day vs. 2 cups/day: aOR = 1.39 (95% CI: 0.85, 2.23)) were not significantly associated with reduced odds of fracture. A statistically significant association was observed between child use of vitamin D supplements and decreased odds of fracture (yes vs. no: aOR = 0.42, 95% CI: 0.25, 0.69). Vitamin D supplementation, but not serum 25-hydroxyvitamin D level or milk intake, was associated with reduced fracture risk among these healthy young children. © The Author 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.

  1. Occupational exposures and non-Hodgkin's lymphoma: Canadian case-control study

    Directory of Open Access Journals (Sweden)

    Spinelli John J

    2008-08-01

    Full Text Available Abstract Background The objective was to study the association between Non-Hodgkin's Lymphoma (NHL and occupational exposures related to long held occupations among males in six provinces of Canada. Methods A population based case-control study was conducted from 1991 to 1994. Males with newly diagnosed NHL (ICD-10 were stratified by province of residence and age group. A total of 513 incident cases and 1506 population based controls were included in the analysis. Conditional logistic regression was conducted to fit statistical models. Results Based on conditional logistic regression modeling, the following factors independently increased the risk of NHL: farmer and machinist as long held occupations; constant exposure to diesel exhaust fumes; constant exposure to ionizing radiation (radium; and personal history of another cancer. Men who had worked for 20 years or more as farmer and machinist were the most likely to develop NHL. Conclusion An increased risk of developing NHL is associated with the following: long held occupations of faer and machinist; exposure to diesel fumes; and exposure to ionizing radiation (radium. The risk of NHL increased with the duration of employment as a farmer or machinist.

  2. Cumulative social disadvantage, ethnicity and first-episode psychosis: a case-control study.

    Science.gov (United States)

    Morgan, C; Kirkbride, J; Hutchinson, G; Craig, T; Morgan, K; Dazzan, P; Boydell, J; Doody, G A; Jones, P B; Murray, R M; Leff, J; Fearon, P

    2008-12-01

    Numerous studies have reported high rates of psychosis in the Black Caribbean population in the UK. Recent speculation about the reasons for these high rates has focused on social factors. However, there have been few empirical studies. We sought to compare the prevalence of specific indicators of social disadvantage and isolation, and variations by ethnicity, in subjects with a first episode of psychosis and a series of healthy controls. All cases with a first episode of psychosis who made contact with psychiatric services in defined catchment areas in London and Nottingham, UK and a series of community controls were recruited over a 3-year period. Data relating to clinical and social variables were collected from cases and controls. On all indicators, cases were more socially disadvantaged and isolated than controls, after controlling for potential confounders. These associations held when the sample was restricted to those with an affective diagnosis and to those with a short prodrome and short duration of untreated psychosis. There was a clear linear relationship between concentrated disadvantage and odds of psychosis. Similar patterns were evident in the two main ethnic groups, White British and Black Caribbean. However, indicators of social disadvantage and isolation were more common in Black Caribbean subjects than White British subjects. We found strong associations between indicators of disadvantage and psychosis. If these variables index exposure to factors that increase risk of psychosis, their greater prevalence in the Black Caribbean population may contribute to the reported high rates of psychosis in this population.

  3. Risk factors for the occurrence of undifferentiated carcinoma of nasopharyngeal type: A case-control study

    OpenAIRE

    Nešić Vladimir; Šipetić Sandra; Vlajinac Hristina; Stošić-Divjak Svetlana; Ješić Snežana

    2010-01-01

    Introduction. The incidence rate of nasopharyngeal carcinoma in Serbia is less than one per 100,000 citizens, which classifies it as a region with low incidence for this disease. Objective. The aim of this study was to test some hypotheses of the risk factors for undifferentiated carcinoma of nasopharyngeal type (UCNT) in the low incidence population. Methods. A case-control study was used for the research. The study included 45 cases with histopathological diagnosis of UCNT and 90 controls. ...

  4. Cardiovascular drugs and the risk of suicide: a nested case-control study

    DEFF Research Database (Denmark)

    Callréus, Torbjörn; Agerskov Andersen, Ulla; Hallas, Jesper

    2007-01-01

    OBJECTIVE: During the past 30 years, various cardiovascular drugs have been implicated as causes of depression or suicide. Although the evidence for causal relationships has generally been conflicting, both beta-blockers and angiotensin-converting-enzyme inhibitors (ACE-inhibitors) have been...... related to depression. Lipid-lowering therapies and calcium-channel blockers have also been linked to an increased risk of suicide. In this study, we investigated the possible association between the use of cardiovascular drugs and suicide using population-based register data. METHODS: We performed...... a nested case-control study in the county of Funen, Denmark, that consisted of 743 cases of completed suicide identified in a Death Registry for the period 1991-1998 and 14,860 age- and sex-matched controls. Information on previous drug use was retrieved from prescription data and the association between...

  5. Vitamin D deficiency in first episode psychosis: a case-control study.

    Science.gov (United States)

    Crews, Matthieu; Lally, John; Gardner-Sood, Poonam; Howes, Oliver; Bonaccorso, Stefania; Smith, Shubulade; Murray, Robin M; Di Forti, Marta; Gaughran, Fiona

    2013-11-01

    Vitamin D deficiency is seen in a high proportion of people with established psychotic disorders, but it is not known if this is present at onset of the illness. We set out to examine vitamin D levels in people with their first episode of psychosis (FEP). We conducted a matched case-control study to examine vitamin D levels and rates of vitamin D deficiency in sixty nine patients presenting with their FEP and sixty nine controls matched for age, sex and ethnicity. Differences between groups were tested using student's-t tests, paired t-tests and odds ratios for further analysis. Vitamin D levels were significantly lower in cases than in controls (pvitamin D deficient was 2.99 in the FEP group relative to the control group. There was no correlation between vitamin D levels and length of hospitalisation in the patient group (r=-0.027, p=0.827). We found higher rates of vitamin D deficiency in people with FEP compared to matched controls. Given that vitamin D is neuroprotective; that developmental vitamin D deficiency may be a risk factor for psychosis, and that incipient psychosis may affect lifestyle factors and diet, future studies are required to examine this association further. In the meantime, there is a need for more widespread testing of vitamin D levels in FEP and for the development of appropriate management strategies. © 2013 Elsevier B.V. All rights reserved.

  6. Varenicline and Risk of Self-Harm: A Nested Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Mina Tadrous

    Full Text Available Smoking remains a serious public health concern. Pharmacotherapy for smoking cessation, including bupropion and varenicline, are proven means to increase quit rates. Post-marketing reports describing suicidal behaviours have raised concerns about the safety of varenicline. However, whether varenicline imparts a higher risk of suicide relative to bupropion remains uncertain.A population-based nested case-control study in Ontario, Canada, from April 1, 2011 to March 31, 2015 was conducted. Subjects were residents of Ontario aged 18 years and older with publicly funded drug coverage receiving either bupropion or varenicline for smoking cessation. We defined cases were those with a hospitalization or emergency department visit for suicide or non-fatal self-harm within 90 days of treatment. For each case, we identified up to fifty controls from the same cohort matched on age, sex, history of self-harm, use of selected psychotropic medications, alcohol abuse and prior admission to a mental health unit. Adjusted odds ratio were used to compare the risk of suicide/self-harm of varenicline to bupropion.We identified 331 cases and 5,346 matched-controls. Following adjustment for potential confounders, we found that varenicline was not associated with an increased risk of suicide/self-harm relative to bupropion (adjusted odds ratio 1.15; 95% confidence interval 0.71 to 1.87.Treatment with varenicline does not appear to significantly increase the risk of suicide or self-harm relative to bupropion.

  7. Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Adenocarcinoma Risk: Nested Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Vitaly Smelov

    Full Text Available A role of Chlamydia trachomatis in HPV-induced cervical carcinogenesis has been reported for cervical cancer but studies on cervical adenocarcinoma are limited.A total of 1,553 cervical smears taken up to 26 years before diagnosis in a large population-based nested case-control study of cervical adenocarcinoma (AC, 132 cases with matched controls, and adenocarcinoma in situ (AIS, 159 cases with matched controls were tested for C. trachomatis and HPV DNA by a type-specific PCR bead-based multiplex genotyping (TS-MPG assay.Only 1.7% of samples were positive for C. trachomatis, with no significant differences between AC/AIS cases and controls. HPV-positivity was detected in 49.3% of C. trachomatis-negative and 65.4% C. trachomatis-positive samples, respectively.A large prospective study did not find any risk for cervical adenocarcinoma and/or AIS conferred by C. trachomatis infection.C. trachomatis appears not to be involved in cervical adenocarcinomas.

  8. Risk factors for acute Toxoplasma gondii diseases in Taiwan: a population-based case-control study.

    Directory of Open Access Journals (Sweden)

    Ting-Yi Chiang

    Full Text Available Although human toxoplasmosis is a notifiable disease in Taiwan since 2007, little is known about its risk factors. This study aimed to investigate the risk factors for acute Toxoplasma gondii diseases in Taiwan. We conducted a nationwide population-based case-control study. Cases of acute human toxoplasmosis notified to the Taiwan Centers for Diseases Control (Taipei, Taiwan during 2008-2013 were compared with controls that were randomly selected from healthy T. gondii-seronegative blood donors who participated in a nationwide T. gondii seroepidemiologic study during 2009-2010. Cases and controls were matched according to age, gender and residency at an 1:8 ratio. Structured questionnaires were used to gather information regarding risk factors. A total of 30 laboratory-confirmed acute T. gondii disease cases and 224 controls were enrolled. The most common clinical manifestation of the cases was flu-like symptoms (n = 20, followed by central nervous system disease (n = 4, ocular diseases (n = 3, abortion (n = 2, and congenital infection (n = 1. Multivariate conditional logistic regression showed that raw clam consumption (adjusted odds ratio [OR] = 3.7; 95% confidence interval [CI] = 1.4-9.9 and having a cat in the household (adjusted OR = 2.9; 95% CI = 1.1-7.9 were two independent risk factors for acute T. gondii disease. We conclude that raw shellfish consumption and domestic cat exposure were risk factors for acquiring acute T. gondii diseases in Taiwan. This finding may guide future research and control policies.

  9. Psychiatric illness, socioeconomic status, and marital status in people committing suicide: a matched case-sibling-control study

    DEFF Research Database (Denmark)

    Agerbo, Esben; Qin, Ping; Mortensen, Preben Bo

    2006-01-01

    of these factors. DESIGN: Nested case-control study. Information on causes of death, psychiatric admission, marital status, children, and socioeconomic factors was obtained from routine registers. SETTING: Denmark. PARTICIPANTS: 985 suicide cases, 1104 sex-age (+/-3 years) matched siblings, and 16 619 controls......STUDY OBJECTIVE: Suicides cluster in both families and persons with psychiatric disorders and socioeconomic disadvantages. This study compares these factors between suicide cases, their siblings, and population based controls in an attempt to evaluate both the familial and the individual element...... and controls in exposure to hospitalised psychiatric disorders and socioeconomic disadvantages, although these factors contribute to the familial aggregation of suicides....

  10. Cancer of the Cervix in Nigeria: A CaseControl Study of some ...

    African Journals Online (AJOL)

    A casecontrol study to establish possible aetiological factor of carcinoma of the cervix was undertaken. Data were collected from 206 patients with carcinoma of cervix and 206 controls using a standardized questionnaire. Risk factors assessed included sociodemographic characteristics, sexual history, personal habit and ...

  11. Association of HCV with diabetes mellitus: an Egyptian case-control study

    Directory of Open Access Journals (Sweden)

    Esmat Gamal G

    2011-07-01

    Full Text Available Abstract Background The highest Hepatitis C Virus (HCV prevalence in the world occurs in Egypt. Several studies from different parts of the world have found that 13% to 33% of patients with chronic HCV have associated diabetes, mostly type II Diabetes Mellitus (DM. In Egypt the prevalence of DM is 25.4% among HCV patients. Therefore, it is important to identify the magnitude of the problem of diabetes in order to optimize the treatment of chronic hepatitis C. Methods The objective of this case-control study was to evaluate the prevalence of DM and other extrahepatic (EH manifestations among patients with different HCV morbidity stages including asymptomatic, chronic hepatic and cirrhotic patients. In this study, 289 HCV patients older than 18 were selected as cases. Also, 289 healthy controls were included. Laboratory investigations including Liver Function tests (LFT and blood glucose level were done. Also serological assays including cryoglobulin profile, rheumatoid factor, antinuclear antibody, HCV-PCR were performed. Results Out of 289 HCV cases, 40 (13.84% were diabetic. Out of 289 healthy controls, 12 (4.15% were diabetic. It was found that the diabetic HCV group mean age was [48.1 (± 9.2]. Males and urbanians represented 72.5% and 85% respectively. Lower level of education was manifested in 52.5% and 87.5% were married. In the nondiabetic HCV group mean age was [40.7 (± 10.4]. Males and urbanians represented 71.5% and 655% respectively. secondary and higher level of education was attained in 55.4% and 76.7% were married. Comparing between the diabetic HCV group and the non diabetic HCV group, age, residence and alcohol drinking were the only significant factors affecting the incidence of diabetes between the two groups. There was no significant difference regarding sonar findings although cirrhosis was more prevalent among diabetic HCV cases and the fibrosis score was higher in diabetic HCV patients than among the non diabetic HCV cases

  12. Pneumocystis jirovecii pneumonia in systemic autoimmune rheumatic disease: A case-control study.

    Science.gov (United States)

    Tadros, Susan; Teichtahl, Andrew J; Ciciriello, Sabina; Wicks, Ian P

    2017-06-01

    Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that affects the immunocompromised. Patients with systemic autoimmune rheumatic disease are increasingly recognised as an at-risk clinical population with a high mortality. This case-control study examined differences in the characteristics and peripheral blood parameters between patients with systemic autoimmune rheumatic disease who developed PJP and gender, age and disease-matched controls. Historical data collected between 2002 and 2013 at the Royal Melbourne Hospital, Australia were reviewed. Cases were defined by having a systemic autoimmune rheumatic disease and a diagnosis of PJP (either a positive toluidine blue O stain or P. jirovecii PCR, with a concurrent respiratory illness that was clinically consistent with PJP). Controls were matched for age, gender and disease in a 4:1 ratio. Peripheral blood results were retrieved from an in-house pathology database. Clinical information including glucocorticoid exposure, PJP prophylaxis, comorbidities and month of admission were retrieved from medical notes. After adjustment for corticosteroid exposure and C-reactive protein, lymphocyte count on admission (0.4 vs. 1.3; p = 0.04) and at nadir (0.2 vs. 0.8 × 10 9 /L; p = 0.05) was significantly lower in cases than in controls. Cases (n = 11) were more frequently Caucasian rather than non-Caucasian (81.8% vs. 65.9%; p = 0.04). In addition, cases more commonly presented in autumn (March to May) than in other seasons (OR = 7.3; 95% CI: 1.4-38.7; p = 0.02). These data demonstrate that patients with systemic autoimmune rheumatic disease who develop PJP have significantly greater lymphopenia than age, gender and disease-matched controls, independent of corticosteroid exposure, as well as a potential ethnicity and seasonal predilection to PJP. This may help to inform prophylactic guidelines for PJP in these patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. A case-control study of risk factors for bovine cysticercosis in Danish cattle herds

    DEFF Research Database (Denmark)

    Calvo Artavia, Francisco Fernando; Nielsen, Liza Rosenbaum; Dahl, J.

    2013-01-01

    than in countries with few lightly infected cases per year. The aim of the present case-control study was to quantify associations between potential herd-level risk factors and BC in Danish cattle herds. Risk factors can be used in the design of a risk-based meat inspection system targeted towards...... a questionnaire and register data from the Danish Cattle Database were grouped into meaningful variables and used to investigate the risk factors for BC using a multivariable logistic regression model. Case herds were almost three times more likely than control herds to let all or most animals out grazing. Case...... the animals with the highest risk of BC. Cases (n = 77) included herds that hosted at least one animal diagnosed with BC at meat inspection, from 2006 to 2010. Control herds (n = 231) consisted of randomly selected herds that had not hosted any animals diagnosed with BC between 2004 and 2010. The answers from...

  14. A case control study of breast cancer risk and exposure to injectable ...

    African Journals Online (AJOL)

    A case control study of breast cancer risk and exposure to injectable progestogen contraceptives. R. Bailie, J Katzenellenbogen, M. Hoffman, G Schierhout, H Truter, D Dent, A Gudgeon, J van Zyl, L Rosenberg, S Shapiro ...

  15. Spironolactone and risk of upper gastrointestinal events: population based case-control study

    NARCIS (Netherlands)

    K.M.C. Verhamme (Katia); G. Mosis (Georgio); B.H.Ch. Stricker (Bruno); M.C.J.M. Sturkenboom (Miriam); J.P. Dieleman (Jeanne)

    2006-01-01

    textabstractOBJECTIVE: To confirm and quantify any association between spironolactone and upper gastrointestinal bleeding and ulcers. DESIGN: Population based case-control study. SETTING: A primary care information database in the Netherlands. PARTICIPANTS: All people on the

  16. Control of Macromolecular Architectures for Renewable Polymers: Case Studies

    Science.gov (United States)

    Tang, Chuanbing

    The development of sustainable polymers from nature biomass is growing, but facing fierce competition from existing petrochemical-based counterparts. Controlling macromolecular architectures to maximize the properties of renewable polymers is a desirable approach to gain advantages. Given the complexity of biomass, there needs special consideration other than traditional design. In the presentation, I will talk about a few case studies on how macromolecular architectures could tune the properties of sustainable bioplastics and elastomers from renewable biomass such as resin acids (natural rosin) and plant oils.

  17. A case-control study on the association between bladder cancer and prior bladder calculus.

    Science.gov (United States)

    Chung, Shiu-Dong; Tsai, Ming-Chieh; Lin, Ching-Chun; Lin, Herng-Ching

    2013-03-15

    Bladder calculus is associated with chronic irritation and inflammation. As there is substantial documentation that inflammation can play a direct role in carcinogenesis, to date the relationship between stone formation and bladder cancer (BC) remains unclear. This study aimed to examine the association between BC and prior bladder calculus using a population-based dataset. This case-control study included 2,086 cases who had received their first-time diagnosis of BC between 2001 and 2009 and 10,430 randomly selected controls without BC. Conditional logistic regressions were employed to explore the association between BC and having been previously diagnosed with bladder calculus. Of the sampled subjects, bladder calculus was found in 71 (3.4%) cases and 105 (1.1%) controls. Conditional logistic regression analysis revealed that the odds ratio (OR) of having been diagnosed with bladder calculus before the index date for cases was 3.42 (95% CI = 2.48-4.72) when compared with controls after adjusting for monthly income, geographic region, hypertension, diabetes, coronary heart disease, and renal disease, tobacco use disorder, obesity, alcohol abuse, and schistosomiasis, bladder outlet obstruction, and urinary tract infection. We further analyzed according to sex and found that among males, the OR of having been previously diagnosed with bladder calculus for cases was 3.45 (95% CI = 2.39-4.99) that of controls. Among females, the OR was 3.05 (95% CI = 1.53-6.08) that of controls. These results add to the evidence surrounding the conflicting reports regarding the association between BC and prior bladder calculus and highlight a potential target population for bladder cancer screening.

  18. Determinants of impaired growth among hospitalized children: a case-control study

    Directory of Open Access Journals (Sweden)

    Marilia de Carvalho Lima

    Full Text Available CONTEXT: Protein energy malnutrition constitutes a public health problem, especially in less affluent countries. The identification of amenable predictive risk factors is of major importance for policy makers to plan interventions to reduce infant malnutrition. OBJECTIVE: To identify risk factors for protein energy malnutrition among hospitalized low-income children aged 6 to 24 months. TYPE OF STUDY: Case-control study. SETTING: Two public hospitals in Recife, Brazil. PARTICIPANTS: The cases were 124 infants with length-for-age below the 10th percentile of the National Center for Health Statistics curve and the controls were 241 infants with length-for-age equal to or above the 10th percentile who were recruited in the same infirmary. METHODS: Cases and controls were compared in relation to a variety of sociodemographic, environmental and reproductive factors, and their healthcare, previous feeding practice and morbidity. Logistic regression analysis was used to investigate the net effect of risk factors on infant malnutrition, after adjusting for potential confounding variables. RESULTS: The mother's age, possession of a TV set, type of water supply, family size and location of the home were significantly associated with child malnutrition in the bivariate analysis. However, these associations lost their significance after adjusting for other explanatory variables in the hierarchical logistic regression analysis. This analysis showed that low birth weight contributed the largest risk for impaired growth. Increased risks of infant malnutrition were also significantly associated with households that had no toilet facilities or refrigerator, high parity for the mother, no breastfeeding of the infant, inadequate vaccination coverage and previous hospitalization for diarrhea and pneumonia. DISCUSSION: The literature shows that chronic malnutrition, as assessed by low length-for-age indexes, is often related to low income. However, this was not the

  19. The effects of umbilical cord entanglement upon labor management and fetal health: retrospective case control study.

    Science.gov (United States)

    Buyukkayaci Duman, Nuriye; Topuz, Senay; Bostanci, Mehmet Omer; Gorkem, Umit; Yuksel Kocak, Derya; Togrul, Cihan; Gungor, Tayfun

    2018-03-01

    This retrospective study aimed at determining prognostic factors that paved the way for umbilical cord entanglement (UCE) and the effects of UCE upon labor management and fetal health. Sixty women who gave term birth with head presentation and received UCE diagnosis following birth composed the case group while another 60 women with the same characteristics who were selected with randomized sampling method and who did not develop UCE comprised the control group. The data obtained were processed with SPSS 22.0 statistical program. T test was used for comparing demographic and obstetric data and mean birth weight of babies in the case group and control group. For comparing data on active labor management and fetal health, numbers, percentages and chi-square test were used. Also for comparing values case: 58.3.0%; control: 21.7%), vacuum assisted vaginal delivery (case: 20.0%; control: 3.3%), forceps assisted vaginal delivery (case: 8.3%; control: 1.7%), fetal distress (case: 60.0%; control: 25.0%), amniotic fluid meconium (case: 58.3%; control: 21.7%), APGAR score less than 7 at the 1st minute (case: 58.3%; control: 21.7%) and APGAR score less than 7 at the 5th minute were higher in the women in the case group than the women in the control group (p < 0.05). UCE increased rates of interventional birth, emergent cesarean delivery, vacuum assisted vaginal delivery, forceps assisted vaginal delivery, amniotic fluid meconium and fetal distress.

  20. Neurocognitive performance in family-based and case-control studies of schizophrenia

    Science.gov (United States)

    Gur, Ruben C.; Braff, David L.; Calkins, Monica E.; Dobie, Dorcas J.; Freedman, Robert; Green, Michael F.; Greenwood, Tiffany A.; Lazzeroni, Laura C.; Light, Gregory A.; Nuechterlein, Keith H.; Olincy, Ann; Radant, Allen D.; Seidman, Larry J.; Siever, Larry J.; Silverman, Jeremy M.; Sprock, Joyce; Stone, William S.; Sugar, Catherine A.; Swerdlow, Neal R.; Tsuang, Debby W.; Tsuang, Ming T.; Turetsky, Bruce I.; Gur, Raquel E.

    2014-01-01

    Background Neurocognitive deficits in schizophrenia (SZ) are established and the Consortium on the Genetics of Schizophrenia (COGS) investigated such measures as endophenotypes in family-based (COGS-1) and case-control (COGS-2) studies. By requiring family participation, family-based sampling may result in samples that vary demographically and perform better on neurocognitive measures. Methods The Penn computerized neurocognitive battery (CNB) evaluates accuracy and speed of performance for several domains and was administered across sites in COGS-1 and COGS-2. Most tests were included in both studies. COGS-1 included 328 patients with SZ and 497 healthy comparison subjects (HCS) and COGS-2 included 1195 patients and 1009 HCS. Results Demographically, COGS-1 participants were younger, more educated, with more educated parents and higher estimated IQ compared to COGS-2 participants. After controlling for demographics, the two samples produced very similar performance profiles compared to their respective controls. As expected, performance was better and with smaller effect sizes compared to controls in COGS-1 relative to COGS-2. Better performance was most pronounced for spatial processing while emotion identification had large effect sizes for both accuracy and speed in both samples. Performance was positively correlated with functioning and negatively with negative and positive symptoms in both samples, but correlations were attenuated in COGS-2, especially with positive symptoms. Conclusions Patients ascertained through family-based design have more favorable demographics and better performance on some neurocognitive domains. Thus, studies that use case-control ascertainment may tap into populations with more severe forms of illness that are exposed to less favorable factors compared to those ascertained with family-based designs. PMID:25432636

  1. Neurocognitive performance in family-based and case-control studies of schizophrenia.

    Science.gov (United States)

    Gur, Ruben C; Braff, David L; Calkins, Monica E; Dobie, Dorcas J; Freedman, Robert; Green, Michael F; Greenwood, Tiffany A; Lazzeroni, Laura C; Light, Gregory A; Nuechterlein, Keith H; Olincy, Ann; Radant, Allen D; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Sprock, Joyce; Stone, William S; Sugar, Catherine A; Swerdlow, Neal R; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Gur, Raquel E

    2015-04-01

    Neurocognitive deficits in schizophrenia (SZ) are established and the Consortium on the Genetics of Schizophrenia (COGS) investigated such measures as endophenotypes in family-based (COGS-1) and case-control (COGS-2) studies. By requiring family participation, family-based sampling may result in samples that vary demographically and perform better on neurocognitive measures. The Penn computerized neurocognitive battery (CNB) evaluates accuracy and speed of performance for several domains and was administered across sites in COGS-1 and COGS-2. Most tests were included in both studies. COGS-1 included 328 patients with SZ and 497 healthy comparison subjects (HCS) and COGS-2 included 1195 patients and 1009 HCS. Demographically, COGS-1 participants were younger, more educated, with more educated parents and higher estimated IQ compared to COGS-2 participants. After controlling for demographics, the two samples produced very similar performance profiles compared to their respective controls. As expected, performance was better and with smaller effect sizes compared to controls in COGS-1 relative to COGS-2. Better performance was most pronounced for spatial processing while emotion identification had large effect sizes for both accuracy and speed in both samples. Performance was positively correlated with functioning and negatively with negative and positive symptoms in both samples, but correlations were attenuated in COGS-2, especially with positive symptoms. Patients ascertained through family-based design have more favorable demographics and better performance on some neurocognitive domains. Thus, studies that use case-control ascertainment may tap into populations with more severe forms of illness that are exposed to less favorable factors compared to those ascertained with family-based designs.

  2. Environment And Genetics in Lung cancer Etiology (EAGLE study: An integrative population-based case-control study of lung cancer

    Directory of Open Access Journals (Sweden)

    Colombi Antonio

    2008-06-01

    Full Text Available Abstract Background Lung cancer is the leading cause of cancer mortality worldwide. Tobacco smoking is its primary cause, and yet the precise molecular alterations induced by smoking in lung tissue that lead to lung cancer and impact survival have remained obscure. A new framework of research is needed to address the challenges offered by this complex disease. Methods/Design We designed a large population-based case-control study that combines a traditional molecular epidemiology design with a more integrative approach to investigate the dynamic process that begins with smoking initiation, proceeds through dependency/smoking persistence, continues with lung cancer development and ends with progression to disseminated disease or response to therapy and survival. The study allows the integration of data from multiple sources in the same subjects (risk factors, germline variation, genomic alterations in tumors, and clinical endpoints to tackle the disease etiology from different angles. Before beginning the study, we conducted a phone survey and pilot investigations to identify the best approach to ensure an acceptable participation in the study from cases and controls. Between 2002 and 2005, we enrolled 2101 incident primary lung cancer cases and 2120 population controls, with 86.6% and 72.4% participation rate, respectively, from a catchment area including 216 municipalities in the Lombardy region of Italy. Lung cancer cases were enrolled in 13 hospitals and population controls were randomly sampled from the area to match the cases by age, gender and residence. Detailed epidemiological information and biospecimens were collected from each participant, and clinical data and tissue specimens from the cases. Collection of follow-up data on treatment and survival is ongoing. Discussion EAGLE is a new population-based case-control study that explores the full spectrum of lung cancer etiology, from smoking addiction to lung cancer outcome, through

  3. Correlation of Serum Zinc Level with Simple Febrile Seizures: A Hospital based Prospective Case Control Study

    Directory of Open Access Journals (Sweden)

    Imran Gattoo

    2015-04-01

    Full Text Available Background: Febrile seizures are one of the most common neurological conditions of childhood. It seems that zinc deficiency is associated with increased risk of febrile seizures.Aim: To estimate the serum Zinc level in children with simple Febrile seizures and to find the correlation between serum zinc level and simple Febrile seizures.Materials and Methods: The proposed study was a hospital based prospective case control study which included infants and children aged between 6 months to 5 years, at Post Graduate Department of Pediatrics, (SMGS Hospital, GMC Jammu, northern India. A total of 200 infants and children fulfilling the inclusion criteria were included. Patients were divided into 100(cases in Group A with simple febrile seizure and 100(controls in Group B of children with acute febrile illness without seizure. All patients were subjected to detailed history and thorough clinical examination followed by relevant investigations.Results: Our study had slight male prepondance of 62% in cases and 58% in controls . Mean serum zinc level in cases was 61.53±15.87 ugm/dl and in controls it was 71.90+18.50 ugm/dl .Serum zinc level was found significantly low in cases of simple febrile seizures as compaired to controls ,with p value of

  4. Medical illness, medication use and suicide in seniors: a population-based case-control study.

    Science.gov (United States)

    Voaklander, D C; Rowe, B H; Dryden, D M; Pahal, J; Saar, P; Kelly, K D

    2008-02-01

    Suicide among seniors is a significant health problem in north America, particularly for men in whom the rates rise steadily after 50 years of age. The goal of this study was to examine elder suicides identified from a large population-based database using case-control methods to determine disease and medication factors related to suicide. A population-based 1 : 5 case-control study was conducted comparing seniors aged 66 years and older who had died by suicide with age and sex-matched controls. Case data were obtained through British Columbia (BC) Vital Statistics, whereas controls were randomly selected from the BC Health Insurance Registry. Cases and controls were linked to the provincial PharmaCare database to determine medication use and the provincial Physician Claims and Inpatient Hospitalization databases to determine co-morbidity. Between 1993 and 2002 a total of 602 seniors died by suicide in BC giving an annual rate of 13.2 per 100,000. Firearms were the most common mechanism (28%), followed by hanging/suffocation (25%), self-poisoning (21%), and jumping from height (7%). In the adjusted logistic model, variables related to suicide included: lower socioeconomic status, depression/psychosis, neurosis, stroke, cancer, liver disease, parasuicide, benzodiazepine use, narcotic pain killer use and diuretic use. There was an elevated risk for those prescribed inappropriate benzodiazepines and for those using strong narcotic pain killers. This study is consistent with previous studies that have identified a relationship between medical or psychiatric co-morbidity and suicide in seniors. In addition, new and potentially useful information confirms that certain types and dosages of benzodiazepines are harmful to seniors and their use should be avoided.

  5. High Spicy Food Intake and Risk of Cancer: A Meta-analysis of Case-control Studies.

    Science.gov (United States)

    Chen, Yu-Heng; Zou, Xiao-Nong; Zheng, Tong-Zhang; Zhou, Qi; Qiu, Hui; Chen, Yuan-Li; He, Mei; Du, Jia; Lei, Hai-Ke; Zhao, Ping

    2017-09-20

    Studies on the association between spicy food intake and cancer risk have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis based on evidence from case-control studies. PubMed, EMBASE, and the Cochrane Library were searched for eligible publications. Combined odds ratios (OR s) with their 95% confidence interval (CI) were calculated using a random- or fixed-effects model. The methodological quality of the included articles was assessed using the Newcastle-Ottawa scale (NOS). All data were analyzed using STATA 11.0 software (version 11.0; StataCorp., College Station, TX, USA). Subgroup analyses were also performed with stratification by region, sex, number of cases, cancer subtype, source of the control group, and NOS score. A total 39 studies from 28 articles fulfilled the inclusion criteria for the meta-analysis (7884 patients with cancer and 10,142 controls). Comparison of the highest versus lowest exposure category in each study revealed a significant OR of 1.76 (95% CI = 1.35-2.29) in spite of significant heterogeneity (P cases, different sources of the control group, and high-quality articles (NOS score of ≥ 7). However, no statistically significant association was observed for women, esophageal cancer, gallbladder cancer, or low-quality articles (NOS score of case-control studies suggested that a higher level of spicy food intake may be associated with an increased incidence of cancer despite significant heterogeneity. More studies are warranted to clarify our understanding of the association between high spicy food intake and the risk of cancer.

  6. Leukemia and brain tumors in Norwegian railway workers, a nested case-control study.

    Science.gov (United States)

    Tynes, T; Jynge, H; Vistnes, A I

    1994-04-01

    In an attempt to assess whether exposure to electromagnetic fields on Norwegian railways induces brain tumors or leukemia, the authors conducted a nested case-control study of railway workers based on incident cases from the Cancer Registry of Norway in a cohort of 13,030 male Norwegian railway workers who had worked on either electric or non-electric railways. The cohort comprised railway line, outdoor station, and electricity workers. The case series comprised 39 men with brain tumors and 52 men with leukemia (follow-up, 1958-1990). Each case was matched on age with four or five controls selected from the same cohort. The exposure of each study subject to electric and magnetic fields was evaluated from cumulative exposure measures based on present measurements and historical data. Limited information on potential confounders such as creosote, solvents, and herbicides was also collected; information on whether the subject had smoked was obtained by interviews with the subjects or work colleagues. The case-control analysis showed that men employed on electric railways, compared with non-electric ones, had an odds ratio for leukemia of 0.70 (adjusted for smoking) and an odds ratio for brain tumor of 0.87. No significant trend was shown for exposure to either magnetic or electric fields. These results do not support an association between exposure to 16 2/3-Hertz electric or magnetic fields and the risk for leukemia or brain tumors.

  7. Oestrogen receptor α gene haplotype and postmenopausal breast cancer risk: a case control study

    International Nuclear Information System (INIS)

    Wedrén, Sara; Stiger, Fredrik; Persson, Ingemar; Baron, John; Weiderpass, Elisabete; Lovmar, Lovisa; Humphreys, Keith; Magnusson, Cecilia; Melhus, Håkan; Syvänen, Ann-Christine; Kindmark, Andreas; Landegren, Ulf; Fermér, Maria Lagerström

    2004-01-01

    Oestrogen receptor α, which mediates the effect of oestrogen in target tissues, is genetically polymorphic. Because breast cancer development is dependent on oestrogenic influence, we have investigated whether polymorphisms in the oestrogen receptor α gene (ESR1) are associated with breast cancer risk. We genotyped breast cancer cases and age-matched population controls for one microsatellite marker and four single-nucleotide polymorphisms (SNPs) in ESR1. The numbers of genotyped cases and controls for each marker were as follows: TA n , 1514 cases and 1514 controls; c.454-397C → T, 1557 cases and 1512 controls; c.454-351A → G, 1556 cases and 1512 controls; c.729C → T, 1562 cases and 1513 controls; c.975C → G, 1562 cases and 1513 controls. Using logistic regression models, we calculated odds ratios (ORs) and 95% confidence intervals (CIs). Haplotype effects were estimated in an exploratory analysis, using expectation-maximisation algorithms for case-control study data. There were no compelling associations between single polymorphic loci and breast cancer risk. In haplotype analyses, a common haplotype of the c.454-351A → G or c.454-397C → T and c.975C → G SNPs appeared to be associated with an increased risk for ductal breast cancer: one copy of the c.454-351A → G and c.975C → G haplotype entailed an OR of 1.19 (95% CI 1.06–1.33) and two copies with an OR of 1.42 (95% CI 1.15–1.77), compared with no copies, under a model of multiplicative penetrance. The association with the c.454-397C → T and c.975C → G haplotypes was similar. Our data indicated that these haplotypes were more influential in women with a high body mass index. Adjustment for multiple comparisons rendered the associations statistically non-significant. We found suggestions of an association between common haplotypes in ESR1 and the risk for ductal breast cancer that is stronger in heavy women

  8. Sleep disturbance in psoriasis - a case-controlled study.

    Science.gov (United States)

    Jensen, P; Zachariae, C; Skov, L; Zachariae, R

    2018-04-28

    Sleep is essential for daytime functioning and health. Given the physical symptoms of psoriasis, a higher prevalence of sleep disorders could be expected. So far, the studies examining sleep disturbance in psoriasis have been of less-than-optimal methodological quality and with mixed results. We aimed to: 1) examine the prevalence of sleep disturbance in patients with plaque psoriasis compared to controls, 2) evaluate associations with health-related quality of life (HRQoL), and 3) examine possible disease-related predictors of disturbed sleep. We used a cross-sectional, case-controlled design. Participants included 179 consecutively recruited patients with plaque psoriasis and 105 controls. Measures included psoriasis severity (Psoriasis Area and Severity index [PASI]); HRQoL (Dermatology Life Quality Index [DLQI]); insomnia severity (Insomnia Severity Index [ISI]); sleep quality (Pittsburgh Sleep Quality Index [PSQI]); stress (Perceived Stress Scale [PSS]); Itch (Itch Severity Scale [ISS]); and depressive symptoms (Beck Depression Inventory [BDI]). Analyses included group comparisons and regression analyses to identify predictors of sleep disturbance. Twenty-five per cent of patients with psoriasis reported clinical insomnia (ISI > 15), compared with 10.5% of controls. In all, 53.9% of patients with psoriasis were poor sleepers (PSQI > 5), compared with 21.9% of controls. Itch was statistically significantly associated with all sleep-related outcomes. A higher proportion of patients with psoriasis suffer from poor sleep than controls from the general population. Itch was the main predictor of impaired sleep. Improved control of psoriasis with decreased itch may improve sleep disturbance in psoriasis. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. H. pylori infection and gastric cancer in Bangladesh: a case-control study.

    Science.gov (United States)

    Sarker, Khandker Kawser; Kabir, Md Jahangir; Bhuyian, A K M Minhaj Uddin; Alam, Md Shahjadul; Chowdhury, Fazle Rabbi; Ahad, M Abdul; Rahman, Md Anisur; Rahman, M Mizanur

    2017-11-01

    Like that of other Asian countries gastric cancer (GC) is also a leading cancer in Bangladesh and also a cause for cancer-related mortality. Infection with Helicobacter pylori ( H. pylori ) is the strongest recognized risk factor for gastric adenocarcinoma. The infection is also prevalent in common people. This case-control study was carried out to find an association between GC and H. pylori infection in the community. To evaluate association of H. pylori and carcinoma of stomach this study was conducted at National Institute of Cancer Research & Hospital, Dhaka from January 2013 to December 2014. H. pylori status was determined serologically by using H. pylori kit in the department of Biochemistry laboratory of Bangabandhu Sheikh Mujib Medical University. In total, 114 patients with GC and 520 patients not having GC were studied as controls. Logistic regression method was used to calculate the odds ratio. Significantly more patients in the case group (86.8%) were found to be seropositive for H. pylori antigen in contrast to the control group (67.5%). All of the cases in the present study were in advanced stage. No significant association between H. pylori seropositivity and tumor location was found. It was noted that undifferentiated gastric carcinoma had slightly more association with H. pylori infection. Younger H. pylori -infected patients had been found to be at higher relative risk for GC than older patients. As there is a strong association found between GC and H. pylori infection special emphasis to eradicate H. pylori infection might reduce the incidence of this dreadly disease.

  10. A Case-Control Study of the Role of Human Papillomavirus in Oesophageal Squamous Cell Carcinoma in Australia

    Directory of Open Access Journals (Sweden)

    Surabhi S. Liyanage

    2014-01-01

    Full Text Available Objective. We investigate the prevalence of human papillomavirus (HPV in oesophageal squamous cell carcinoma (OSCC tissues compared to oesophageal tissue from healthy controls, in an Australian cohort. Methods. We conducted a hospital-based case-control study of 99 patients with OSCC and 100 healthy controls to examine the presence of HPV DNA. Paraffin tissues were tested using the PapType high-risk HPV detection and genotyping kit and with INNO-LiPA HPV Genotyping Extra. The biopsy samples were tested for HPV using a PCR-ELISA method based on the L1 consensus primer set PGMY09-PGMY11. Results. HPV DNA of the oncogenic genotype 16 was detected in 1/99 case specimens, a rate of 1010 per 100,000 (95% CI: 30–5500. All control specimens were negative for HPV. Significantly higher rates of smoking, other aerodigestive cancers, and mortality were seen among cases than controls. A pooled analysis of this study and the only other Australian case-control study found that 9/321 cases and 0/155 controls were positive for HPV. The pooled odds ratio for HPV being a risk factor for OSCC was 9.35 (95% CI: 0.47–190.33. Conclusion. Our results suggest that in this multifactorial cancer HPV may be an additional risk factor; although a larger, better powered study is needed.

  11. Quantitative measurement of interocular suppression in anisometropic amblyopia: a case-control study.

    Science.gov (United States)

    Li, Jinrong; Hess, Robert F; Chan, Lily Y L; Deng, Daming; Yang, Xiao; Chen, Xiang; Yu, Minbin; Thompson, Benjamin

    2013-08-01

    The aims of this study were to assess (1) the relationship between interocular suppression and visual function in patients with anisometropic amblyopia, (2) whether suppression can be simulated in matched controls using monocular defocus or neutral density filters, (3) the effects of spectacle or rigid gas-permeable contact lens correction on suppression in patients with anisometropic amblyopia, and (4) the relationship between interocular suppression and outcomes of occlusion therapy. Case-control study (aims 1-3) and cohort study (aim 4). Forty-five participants with anisometropic amblyopia and 45 matched controls (mean age, 8.8 years for both groups). Interocular suppression was assessed using Bagolini striated lenses, neutral density filters, and an objective psychophysical technique that measures the amount of contrast imbalance between the 2 eyes that is required to overcome suppression (dichoptic motion coherence thresholds). Visual acuity was assessed using a logarithm minimum angle of resolution tumbling E chart and stereopsis using the Randot preschool test. Interocular suppression assessed using dichoptic motion coherence thresholds. Patients exhibited significantly stronger suppression than controls, and stronger suppression was correlated significantly with poorer visual acuity in amblyopic eyes. Reducing monocular acuity in controls to match that of cases using neutral density filters (luminance reduction) resulted in levels of interocular suppression comparable with that in patients. This was not the case for monocular defocus (optical blur). Rigid gas-permeable contact lens correction resulted in less suppression than spectacle correction, and stronger suppression was associated with poorer outcomes after occlusion therapy. Interocular suppression plays a key role in the visual deficits associated with anisometropic amblyopia and can be simulated in controls by inducing a luminance difference between the eyes. Accurate quantification of suppression

  12. Case-controlled Study on Risk Factors for the Development of Constipation in Hospitalized Patients

    OpenAIRE

    Ueki, Tetsuya; Nagai, Keiko; Ooe, Nobuharu; Nakashima, Mihoko N.; Nishida, Koyo; Nakamura, Junzo; Nakashima, Mikiro

    2011-01-01

    Constipation is a common problem in hospitalized patients; however, the relative risks of its development with various factors have not been clarified. To clarify the risk factors associated with constipation, we performed a case-controlled study of 165 hospitalized patients who were not laxative users on admission. They were divided into case (n=35) and control (n=130) groups according to laxative administration during hospitalization. Comparison of the patient backgrounds in the two groups ...

  13. Epilepsy and risk of suicide: a population-based case-control study

    DEFF Research Database (Denmark)

    Christensen, Jakob; Vestergaard, Mogens; Mortensen, Preben Bo

    2007-01-01

    by sex, birth year, and calendar date, were assigned to each suicide case. FINDINGS: We identified 21 169 cases of suicide and 423 128 controls. 492 (2.32%) individuals who committed suicide had epilepsy compared with 3140 (0.74%) controls, corresponding to a three times higher risk (rate ratio [RR] 3...

  14. Role of health determinants in a measles outbreak in Ecuador: a case-control study with aggregated data

    OpenAIRE

    María F. Rivadeneira; Sérgio L. Bassanesi; Sandra C. Fuchs

    2018-01-01

    Abstract Background In 2011–2012, an outbreak of measles occurred in Ecuador. This study sought to ascertain which population characteristics were associated. Methods Case-control study of aggregate data. The unit of analysis was the parish (smallest geographic division). The national communicable disease surveillance database was used to identify 52 case parishes (with at least one confirmed case of measles) and 972 control parishes (no cases of measles). A hierarchical model was used to det...

  15. The association of dietary pattern and breast cancer in Jiangsu, China: A population-based case-control study

    NARCIS (Netherlands)

    Lu, S.; Qian, Y.; Huang, X.; Yu, H.; Yang, J.; Han, R.; Su, J.; Du, W.; Zhou, J; Dong, M.; Yu, X.; Duijnhoven, F.; Kampman, E.; Wu, M.

    2017-01-01

    This study aims to examine the association of breast cancer with dietary patterns among Chinese women. A population-based case-control study was conducted in Jiangsu, China. Newly diagnosed primary breast cancer patients were recruited as cases (n = 818). Controls (n = 935), selected from the

  16. Risk factors for fatality among confirmed adult dengue inpatients in Singapore: a matched case-control study.

    Directory of Open Access Journals (Sweden)

    Tun-Linn Thein

    Full Text Available OBJECTIVES: To identify demographic, clinical and laboratory risk factors for death due to dengue fever in adult patients in Singapore. METHODS: Multi-center retrospective study of hospitalized adult patients with confirmed dengue fever in Singapore between 1 January 2004 and 31 December 2008. Non-fatal controls were selected by matching age and year of infection with fatal cases. World Health Organization 1997, 2009 criteria were applied to define dengue hemorrhagic fever (DHF, warning signs and severe dengue. Statistical significance was assessed by conditional logistic regression modeling. RESULTS: Significantly more fatal cases than matched controls had pre-existing co-morbid conditions, and presented with abdominal pain/tenderness. Median pulse rates were significantly higher while myalgia was significantly less frequent in cases. . Fatal cases also had higher leucocyte counts, platelet counts, serum sodium, potassium, urea, creatine and bilirubin levels on admission compared to controls. There was no statistical significant difference between the prevalence of DHF and hematocrit level among cases and controls. Multivariate analysis showed myalgia and leucocyte count at presentation were independent predictors of fatality (adjusted odds ratios 0.09 and 2.94 respectively. None of the controls was admitted to intensive care unit (ICU or given blood transfusion, while 71.4% and 28.6% of fatal cases received ICU admission and blood transfusion. CONCLUSIONS: Absence of myalgia and leucocytosis on admission were independently associated with fatality in our matched case-control study. Fatalities were also commonly associated with co-morbidities and clinicians should be alarmed if dengue patients fulfilled severe dengue case definition on admission.

  17. A case-control study assessing bone mineral density in severe haemophilia A in the UK.

    Science.gov (United States)

    Wells, A J; McLaughlin, P; Simmonds, J V; Prouse, P J; Prelevic, G; Gill, S; Chowdary, P

    2015-01-01

    It has been shown that bone mineral density (BMD) may be lower in patients with haemophilia (PWH). A comparison to control subjects is required to thoroughly assess current BMD in PWH in the UK. The objective of this study was to test the hypothesis that BMD is lower in PWH than in controls, and in patients with more severely affected joints or lower activity levels. In this case-control study, 37 patients with severe haemophilia A were recruited from two haemophilia centres in the UK. A group of 37 age, gender and ethnicity-matched control participants were recruited. All participants had a bone density scan, a musculoskeletal assessment, a blood test for vitamin D and completed a functional activity questionnaire. Of the case group, 5% had osteoporosis and 24% had BMD lower than expected for age. No control participants had osteoporosis, 3% had osteopenia and 14% had BMD lower than expected for age. Ninety one per cent of case participants and 92% of control participants had reduced 25(OH)D levels. Case participants had significantly lower BMD than control participants, and case participants with more severely affected joints, lower activity levels, HIV, history of hepatitis C or lower BMI had significantly lower BMD. Patients with severe haemophilia have a higher risk of low BMD than men without haemophilia. Patients with more severely affected joints and lower activity levels have lower BMD. It remains unclear whether patients with low BMD reached adequate peak bone mass. Low vitamin D may be present in the majority of PWH. © 2014 John Wiley & Sons Ltd.

  18. Serum Taurine and Stroke Risk in Women: A Prospective, Nested Case-Control Study

    Science.gov (United States)

    Wu, Fen; Koenig, Karen L.; Zeleniuch-Jacquotte, Anne; Jonas, Saran; Afanasyeva, Yelena; Wójcik, Oktawia P.; Costa, Max; Chen, Yu

    2016-01-01

    Background Taurine (2-aminoethanesulfonic acid), a conditionally essential sulfur-containing amino acid, is mainly obtained from diet in humans. Experimental studies have shown that taurine’s main biological actions include bile salt conjugation, blood pressure regulation, anti-oxidation, and anti-inflammation. Methods We conducted a prospective case-control study nested in the New York University Women’s Health Study, a cohort study involving 14,274 women enrolled since 1985. Taurine was measured in pre-diagnostic serum samples of 241 stroke cases and 479 matched controls. Results There was no statistically significant association between serum taurine and stroke risk in the overall study population. The adjusted ORs for stroke were 1.0 (reference), 0.87 (95% CI, 0.59–1.28), and 1.03 (95% CI, 0.69–1.54) in increasing tertiles of taurine (64.3–126.6, 126.7–152.9, and 153.0–308.5 nmol/mL, respectively). A significant inverse association between serum taurine and stroke risk was observed among never smokers, with an adjusted OR of 0.66 (95% CI, 0.37–1.18) and 0.50 (95% CI, 0.26–0.94) for the second and third tertile, respectively (p for trend = 0.01), but not among past or current smokers (p for interaction taurine and stroke risk, although a protective effect was observed in never smokers, which requires further investigation. Taurine, Stroke, Epidemiology, Prospective, Case-control study, NYUWHS. PMID:26866594

  19. Risk factors for indigenous Campylobacter jejuni and Campylobacter coli infections in The Netherlands: a case-control study

    NARCIS (Netherlands)

    Doorduyn, Y.; Brandhof, van den W.E.; Duynhoven, van Y.T.H.P.; Breukink, B.J.; Wagenaar, J.A.; Pelt, van W.

    2010-01-01

    A case-control study comprising 1315 Campylobacter jejuni cases, 121 Campylobacter coli cases and 3409 frequency-matched controls was conducted in The Netherlands in 2002-2003. Risk factors for both C. jejuni and C. coli enteritis were consumption of undercooked meat and barbecued meat, ownership of

  20. Gingivitis and periodontitis as a risk factor for stroke: A case-control study in the Iranian population.

    Science.gov (United States)

    Hashemipour, Maryam Alsadat; Afshar, Afsaneh Jahanshahi; Borna, Roya; Seddighi, Behnas; Motamedi, Amin

    2013-09-01

    Periodontitis and gingivitis are one of the most infectious diseases in human. Several studies have been carried out on dependence of periodontitis and stroke. The aim of this study was to investigate the gingivitis and periodontitis as a risk factor for stroke in Iranian population. A case-control study was conducted on 100 patients suffering from stroke as case group, and 100 hospitalized patients as control group. The case group included 42 males and 58 females, and in control group there were 44 males and 56 females. Using a University of North Carolina-15 manual probe, the clinical attachment level, the distance between the cemento-enamel junction and the probed base of the periodontal pocket, were recorded by gingival and periodontal indexes. The data were analyzed by multiple logistic regressions, Chi-square test, Fisher's test, t-test, Man Whitney, and SPSS11.5 software program. P > 0.05 was considered as significant. The case group included 42 males and 58 females, and in control group 44 males and 56 females were included. In this investigation, the average of gingival index in men and women of case group was 1.22 ± 0.55 and 1.31 ± 0.55, respectively. This study showed that the average of gingival index in case group was more than control group. Periodontal index in both groups in men was more than women. The moderate and severe periodontitis in case group were more than that of control group (P = 0.003, P = 0.001). The result of this study shows that there is a significant relation between stroke and periodontal index; however, there isn't any significant relation between stroke and gingival index.

  1. Driving behaviors and on-duty road accidents: a French case-control study.

    Science.gov (United States)

    Fort, Emmanuel; Chiron, Mireille; Davezies, Philippe; Bergeret, Alain; Charbotel, Barbara

    2013-01-01

    A case-control study was carried out to identify driving behaviors associated with the risk of on-duty road accident and to compare driving behaviors according to the type of journey (on duty, commuting, and private) for on-duty road accident victims. Cases were recruited from the Rhône Road Trauma Registry between January 2004 and October 2005 and were on duty at the time of the accident. Control subjects were recruited from the electoral rolls of the case subjects' constituencies of residence. Cases' and controls' driving behavior data were collected by self-administered questionnaire. A logistic regression was performed to identify behavioral risk factors for on-duty road accidents, taking into account age, sex, place of residence, road accident risk exposure, socio-occupational category, and type of road user. A second analysis focused specifically on the case subjects, comparing their self-assessed usual behaviors according to the type of journey. Significant factors for multivariate analysis of on-duty road accidents were female gender, history of on-duty road accidents during the previous 10 years, severe time pressure at work, and driving a vehicle not belonging to the driver. On-duty road accident victims reported behavioral risk factors more frequently in relation to driving for work than driving for private reasons or commuting: nonsystematic seat belt use, cell phone use at least once daily while driving, and history of accidents with injury during the previous 10 years. This study provides knowledge on behavioral risk factors for on-duty road accidents and differences in behavior according to the type of journey for subjects who have been on-duty road accident victims. These results will be useful for the design of on-duty road risk prevention.

  2. Pituitary tumor risk in relation to mobile phone use: A case-control study.

    Science.gov (United States)

    Shrestha, Mithila; Raitanen, Jani; Salminen, Tiina; Lahkola, Anna; Auvinen, Anssi

    2015-01-01

    The number of mobile phone users has grown rapidly, which has generated mounting public concern regarding possible health hazards. This study aims to assess pituitary tumor risk, as it has rarely been investigated. A case-control study was conducted with 80 eligible cases identified from all five university hospitals in Finland and frequency-matched 240 controls from the national population register. Controls were matched to cases by age, sex, region of residence and date of interview. A detailed history of mobile phone use was obtained using a structured interview. Several indicators of mobile phone use were assessed using conditional logistic regression. A reduced odds ratio was seen among regular mobile phone users [OR 0.39, 95% confidence interval (CI) 0.21, 0.72] relative to never/non-regular users, possibly reflecting methodological limitations. Pituitary tumor risk was not increased after 10 or more years since first use (OR 0.69, 95% CI 0.25, 1.89). The risk was not increased in relation to duration, cumulative hours of use, or cumulative number of calls. The results were similar for analog and digital phones. We found no excess risk associated with self-reported short- or medium-term use of mobile phones. This is consistent with most of the published studies. However, uncertainties remained for longer duration of use, as a very small proportion of study participants reported use beyond 10 years.

  3. Pesticide Exposure and Head and Neck Cancers: A Case-Control Study in an Agricultural Region

    Directory of Open Access Journals (Sweden)

    Maryam Amizadeh

    2017-09-01

    Full Text Available Introduction: Causes of head and neck cancers (HNCs are multifactorial, and few studies have investigated the association between chemical exposure and HNCs. The objective of this study was to investigate associations between HNCs, agricultural occupations, and pesticide exposure. The potential for the accumulation of pesticides in the adipose tissue of patients was also investigated.   Materials and Methods: A structured questionnaire was used to collect information on demographics, occupation, and exposure to pesticides in a hospital-based case-control study. Pesticide residue in the adipose tissue of the neck in both cases and controls was also monitored via gas chromatography–mass spectroscopy.   Results: Thirty-one HNC cases were included in this study as well as 32 gender-, age-, and smoking-matched controls. An agricultural occupation was associated with HNC (odds ratio [OR], 3.26; 95% confidence interval [CI], 1.13–9.43 after controlling for age, sex, and smoking. Pesticide exposure was associated with total HNC cases (OR, 7.45; 95% CI, 1.78–3.07 and larynx cancer (OR, 9.33; 95% CI, 1.65–52.68. A dose-response pattern was observed for HNC cases (P=0.06 and larynx cancer (P=0.01. In tracing the pesticide residue, five chlorinated pesticides, namely dichlorodiphenyltrichloroethane (DDT, dichlorodipheny-ldichloroethane (DDD, dichlorodiphenyldichloroethylene (DDE, dieldrin, and lindane, were identified in the adipose tissue. Chlorinated pesticide detection was significantly associated with HNC (OR, 3.91; 95% CI 0.9–0.16.9.   Conclusion: HNCs were found to be associated with pesticide exposure after controlling for confounders. A high education level was identified as a modifying factor decreasing the risk of HNCs. Further studies with larger number of subjects are recommended to assess these relationships in greater detail.

  4. Lateral Epicondylitis and Tobacco Use: A Case-Control Study.

    Science.gov (United States)

    Michienzi, Avery E; Anderson, Christopher P; Vang, Sandy; Ward, Christina M

    2015-01-01

    Although lateral epicondylitis (LE) is a very common tendinopathy, we understand little about the etiology of the disease. Tobacco use has been associated with other tendinopathies, and the purpose of this study is to determine if there is an association between the incidence of lateral epicondylitis and tobacco use. We performed a retrospective cohort study of adult patients diagnosed with lateral epicondylitis. Patients from a single orthopaedic surgeon's practice with LE were matched to control patients with other common upper extremity conditions based on age, gender, and occupation. A total of 65 case patients and 217 control patients were included in the study. The incidence of smoking in patients with lateral epicondylitis was compared to the incidence of smoking in the control group. Of the LE patients, 30/65 (46.2%) were non-smokers, 23/65 (35.4%) were former smokers, and 12/65 (18.5%) were current smokers. Of the control patients, 121/217 (55.8%) were non-smokers, 45/217 (20.7%) were former smokers, and 51/217 (23.5%) were current smokers. The odds of LE patients being former or current smokers compared to control patients were 1.45 times higher, but this was not statistically significant. Among people who did not smoke at the time of presentation, the odds of being a former smoker were 2.28 times higher in LE patients than in controls, which was statistically significant. The odds of being a former smoker were significantly higher in patients with lateral epicondylitis compared to patients with other upper extremity conditions. Although it did not reach statistical significance, the odds of being former or current smokers were also higher in the LE group. These results suggest a relationship between smoking history and incidence of lateral epicondylitis, though more research is needed to determine the exact nature of the relationship. Prognostic, Level III.

  5. Weight, height, body mass index and risk of breast cancer in postmenopausal women: a case-control study

    Directory of Open Access Journals (Sweden)

    Vahdaninia Mariam

    2008-09-01

    Full Text Available Abstract Background Many women in Iran have a relatively high body mass index. To investigate whether the condition contributes to excess breast cancer cases, a case-control study was conducted to assess the relationships between anthropometric variables and breast cancer risk in Tehran, Iran. Methods All incident cases of breast cancer in the Iranian Centre for Breast Cancer (ICBC were identified through the case records. Eligible cases were all postmenopausal women with histological confirmed diagnosis of breast cancer during 1996 to year 2000. Controls were randomly selected postmenopausal women attending the ICBC for clinical breast examination during the same period. The body mass index (BMI was calculated based on weights and heights as measured by the ICBC nursing staff. Both tests for trend and logistic regression analysis were performed to calculate odds ratios and 95% confidence intervals as measures of relative risk. Results In all, 116 breast cancer cases and 116 controls were studied. There were no significant differences between cases and control with regard to most independent variables studied. However, a significant difference was observed between cases and controls indicating that the mean BMI was higher in cases as compared to controls (P = 0.004. Performing logistic regression analysis while controlling for age, age at menopause, family history of breast cancer and parity, the results showed that women with a BMI in the obese range had a three fold increased risk of breast cancer [odds ratio (OR = 3.21, 95% confidence interval (CI: 1.15–8.47]. Conclusion The results suggest that obesity in postmenopausal women could increase risk of breast cancer and it merits further investigation in populations such as Iran where it seems that many women are short in height, and have a relatively high body mass index.

  6. Management of linear quadratic regulator optimal control with full-vehicle control case study

    Directory of Open Access Journals (Sweden)

    Rodrigue Tchamna

    2016-09-01

    Full Text Available Linear quadratic regulator is a powerful technique for dealing with the control design of any linear and nonlinear system after linearization of the system around an operating point. For small systems, which have fewer state variables, the transformation of the performance index from scalar to matrix form can be straightforward. On the other hand, as the system becomes large with many state variables and controllers, appropriate design and notations should be defined to make it easy to automatically implement the technique for any large system without the need to redesign from scratch every time one requires a new system. The main aim of this article was to deal with this issue. This article shows how to automatically obtain the matrix form of the performance index matrices from the scalar version of the performance index. Control of a full-vehicle in cornering was taken as a case study in this article.

  7. Reduced Risk of Barrett's Esophagus in Statin Users: Case-Control Study and Meta-Analysis.

    Science.gov (United States)

    Beales, Ian L P; Dearman, Leanne; Vardi, Inna; Loke, Yoon

    2016-01-01

    Use of statins has been associated with a reduced incidence of esophageal adenocarcinoma in population-based studies. However there are few studies examining statin use and the development of Barrett's esophagus. The purpose of this study was to examine the association between statin use and the presence of Barrett's esophagus in patients having their first gastroscopy. We have performed a case-control study comparing statin use between patients with, and without, an incident diagnosis of non-dysplastic Barrett's esophagus. Male Barrett's cases (134) were compared to 268 male age-matched controls in each of two control groups (erosive gastro-esophageal reflux and dyspepsia without significant upper gastrointestinal disease). Risk factor and drug exposure were established using standardised interviews. Logistic regression was used to compare statin exposure and correct for confounding factors. We performed a meta-analysis pooling our results with three other case-control studies. Regular statin use was associated with a significantly lower incidence of Barrett's esophagus compared to the combined control groups [adjusted OR 0.62 (95 % confidence intervals 0.37-0.93)]. This effect was more marked in combined statin plus aspirin users [adjusted OR 0.43 (95 % CI 0.21-0.89)]. The inverse association between statin or statin plus aspirin use and risk of Barrett's was significantly greater with longer duration of use. Meta-analysis of pooled data (1098 Barrett's, 2085 controls) showed that statin use was significantly associated with a reduced risk of Barrett's esophagus [pooled adjusted OR 0.63 (95 % CI 0.51-0.77)]. Statin use is associated with a reduced incidence of a new diagnosis of Barrett's esophagus.

  8. Association Between Zolpidem Use and Glaucoma Risk: A Taiwanese Population-Based Case-Control Study

    OpenAIRE

    Ho, Yi-Hao; Chang, Yue-Cune; Huang, Wei-Cheng; Chen, Hsin-Yi; Lin, Che-Chen; Sung, Fung-Chang

    2015-01-01

    Background To date, the relationship between zolpidem use and subsequent risk of glaucoma in a Taiwanese population has not been assessed. Methods We used data from the National Health Insurance system to investigate whether zolpidem use was related to glaucoma risk. A 1:4 matched case-control study was conducted. The cases were patients newly diagnosed with glaucoma from 2001 to 2010. The controls were randomly selected non-glaucoma subjects matched by sex and age (?5 years). Zolpidem exposu...

  9. Intrapartum electrocardiogram alteration in fetuses with congenital heart disease: a case-control study.

    Science.gov (United States)

    Gay, Estelle; Bornallet, Géraldine; Gaucherand, Pascal; Doret, Muriel

    2015-11-01

    To assess if the fetal electrocardiogram especially ST segment is modified by congenital heart diseases: modifications in frequencies of the different ST events and modifications in signal quality. A retrospective case-control study, comparing frequencies of the different ST events and the quality of the signal between fetuses with congenital heart diseases and fetuses without congenital heart disease. From 2000 to 2011, fifty-eight fetuses with congenital heart disease had their heart rate recording using a STAN device during labor. Control group was fetuses who were born just before a case and had a STAN as a second line for intrapartum surveillance. Cases and controls were matched on parity, gestational age at birth, presence of growth restriction and umbilical artery pH. Frequencies of the different ST event and quality of the signal were first analyzed for the global labor recording, and then separately for the first and the second phase of labor. No statistically significant difference in ST event frequencies between fetuses with congenital heart disease and the control group was found. Regarding the quality of the signal, 11.49% (±18.82) of recording time is a signal loss for fetus with congenital heart disease whereas only 5.18% (±10.67) for the control group (p=0.028). This is the first study investigating for intrapartum electrocardiogram modification in fetus with congenital heart disease. Congenital heart diseases do not modify frequencies of ST events. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. [Accidents with biological materials among nurses in a training hospital: case-control study].

    Science.gov (United States)

    Dalarosa, Micheline Gisele; Lautert, Liana

    2009-03-01

    This case-control study aimed at analyzing the association between occupational stress and disagreement between chronotype and the work shift of nurses who suffered accidents with biological materials in a hospital of Porto Alegre, Rio Grande do Sul, Brazil. A number of 99 workers who suffered accidents (cases) and 232 that had not suffered accidents (controls) were interviewed. Data were collected through the Job Stress Scale according to Karasek's model and the Horne-Ostberg scale The occurrence of accident was not statistically associated with high work requirement scores (p = 0.317), with a chronobiological profile discordant with work shift (p = 0.563), or with other labor variables associated to accidents--overtime, having two jobs (p = 1.000). In addition, there was no significant difference (chi2 Pearson; p = 1.00) among the scores of professionals with high work requirements who work in shifts discordant with their chronotype, both in the case group and in the control group as well.

  11. Risk Factors of Congenital Heart Diseases: A Case-Control Study inNorthwest Iran.

    Science.gov (United States)

    Naghavi-Behzad, Mohammad; Alizadeh, Mahasti; Azami, Saber; Foroughifar, Shirin; Ghasempour-Dabbaghi, Khazar; Karzad, Nazila; Ahadi, Hamid-Reza; Naghavi-Behzad, Ali

    2013-01-01

    Congenital heart diseases are of immense importance and also a high prevalence. Contributing factors to developing these defects have not been abundantly studied. Therefore, the current study was conducted aiming at determining the effective factors on Congenital Heart Disease (CHD) in newborn infants of Northwest Iran. A case-control study was carried out in North-West of Iran from 2002 to 2012 and a total of 473 infants entered the study. Required data were obtained through check lists completed by the information of hospital records and interview with mothers of 267 newborn infants with CHD together with medical records of mothers as the case group, and 206 medical records of healthy infants at the same period all together with those of their mothers as the control group. The obtained data were statistically analyzed using descriptive statistical methods, T-test, Spearman's correlation coefficient, and Multi-variable Logistic Regression Model (OR with 95% CI), using SPSS.19. In the present study, P value less than 0.05 was considered statistically significant. Based on the results of univariable analyses, the number of previous cesarean sections, past medical history of diseases, gestational age (GA), fetal weight at birth, diastolic blood pressure, fetal heart rate, pulse rate, fetal hemoglobin and hematocrit levels, and fetal head circumference at birth have significant relationship with incidence of congenital abnormalities (Prelationship with CHD incidence. Based on the results of present study, in order to control and reduce the cases of CHD, it is crucial to make proper decisions and implement policies for reducing cesarean cases, lowering consanguineous marriages, providing proper pre-marriage counseling, prompt treatment of mothers' illnesses, improving pregnancy health care and mothers' health status for the purpose of better well-being of newborn infants.

  12. Risk Factors of Congenital Heart Diseases: A Case-Control Study in Northwest Iran

    Directory of Open Access Journals (Sweden)

    Naghavi-Behzad Mohammad

    2013-03-01

    Full Text Available Introduction: Congenital heart diseases are of immense importance and also a high prevalence. Contributing factors to developing these defects have not been abundantly studied. Therefore, the current study was conducted aiming at determining the effective factors on Congenital Heart Disease (CHD in newborn infants of Northwest Iran. Methods: A case-control study was carried out in North-West of Iran from 2002 to 2012 and a total of 473 infants entered the study. Required data were obtained through check lists completed by the information of hospital records and interview with mothers of 267 newborn infants with CHD together with medical records of mothers as the case group, and 206 medical records of healthy infants at the same period all together with those of their mothers as the control group. The obtained data were statistically analyzed using descriptive statistical methods, T-test, Spearman’s correlation coefficient, and Multi-variable Logistic Regression Model (OR with 95% CI, using SPSS.19. In the present study, P value less than 0.05 was considered statistically significant. Results: Based on the results of univariable analyses, the number of previous cesarean sections, past medical history of diseases, gestational age (GA, fetal weight at birth, diastolic blood pressure, fetal heart rate, pulse rate, fetal hemoglobin and hematocrit levels, and fetal head circumference at birth have significant relationship with incidence of congenital abnormalities (P<0.05. Family history, past cesarean sections history, past medical history and GA had significant relationship with CHD incidence. Conclusion: Based on the results of present study, in order to control and reduce the cases of CHD, it is crucial to make proper decisions and implement policies for reducing cesarean cases, lowering consanguineous marriages, providing proper pre-marriage counseling, prompt treatment of mothers’ illnesses, improving pregnancy health care and mothers

  13. Association between protozoa in sputum and asthma: a case-control study.

    Science.gov (United States)

    van Woerden, Hugo C; Ratier-Cruz, Adriana; Aleshinloye, Olabode B; Martinez-Giron, Rafael; Gregory, Clive; Matthews, Ian P

    2011-06-01

    Atypical infectious agents have been proposed as potential contributors to asthma. A novel set of morphological and staining criteria permit the identification of flagellated protozoa in sputum. This case-control study was designed to use this novel method and to assess: (1) are protozoa more common in asthmatics than in non-asthmatics; (2) is the presence of protozoa associated with the use of steroid inhalers; and (3) is the presence of protozoa associated with living in damp housing? Induced sputum samples were collected from asthma patients and local non-atopic, non-smoking controls. Questionnaires assessed asthma severity and housing conditions. Sputum was examined for flagellated protozoa using a previously described staining technique. 96 participants were recruited for this study; 54 asthma patients and 42 controls, age range 21-62 years, 70% female participants. Limiting results to those who were clearly positive or negative for flagellated protozoa, 66.7% (20/30) of asthmatics and 30.8% (4/13) of controls had protozoa (p = 0.046). Among the asthma patients, prevalence of protozoa was not significantly different between those who had (10/18), and those who had not (10/12), used steroid inhaler in the preceding two weeks (p = 0.11). Similarly, the prevalence of protozoa was not significantly different between those who did (6/11) and those who did not (18/32), live in damp homes (p = 0.92). This case-control study demonstrates an association between flagellated protozoa in sputum and asthma. It is now necessary to confirm and characterise the protozoa using genetic techniques based on 18S ribosomal RNA. Once tis is established it would be worthwhile to determine if asthma symptoms improve when treated by anti-protozoal agents. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Potential of public transit as a transportation control measure: Case studies

    Energy Technology Data Exchange (ETDEWEB)

    Sillings, M.

    1998-07-01

    This report is the final product of the Clean Air Project of the National Association of Regional Councils/NARC. It documents a nationwide study of transit projects and programs initiated in the wake of the 1990 Clean Air Act Amendments/CAAA and the Intermodal Surface Transportation Efficiency Act of 1991/ISTEA. The study purpose was to assess the experience, limitations, and value of public transit as a potential transportation control measure/TCM, i.e., generates significant air quality benefits by eliminating or reducing emissions from motor vehicles. Four in-depth case studies and six additional projects featured as innovations in transportation are offered as examples investigating the potential of transit as a TCM. These case studies and innovations highlight the efforts of ten metropolitan areas and transit agencies which have succeed in developing and implementing innovative transit strategies.

  15. A case control study of risk factors associated with female breast cancer

    International Nuclear Information System (INIS)

    Nazir, N.; Waheed, A.; Farhat, K.; Ismail, M.

    2015-01-01

    To find the association of various risk factors with breast cancer. Study Design: It was a case-control study. Place and Duration of Study: The study was carried out in NORI Hospital Islamabad and Combined Military Hospital Rawalpindi between August, 2013 and February, 2014. Material and Methods: Two hundred breast cancer patients and 200 control subjects were inducted. A short approved and planned questionnaire was used to collect data regarding basic demographic, menstrual and reproductive characteristics of participating females. Cases and controls were then interviewed after taking written consent. Results: Breast cancer patients and control subjects did not differ regarding age (p = 0.15), early menarche (OR for menarche at <13 years vs. ?13=1.3, 95% CI = 0.84 - 2.02), and history of breast cancer in 1st degree relatives did not increase breast cancer risk (OR = 1.0, 95% CI = 0.57 - 1.74). Nulliparous women had significantly higher risk than parous women (OR = 2.43, 95% CI = 1.22 - 4.84) and women with late menopause compared to women with early onset of menopause were also at higher risk for breast cancer (OR for menopause at ? 50 vs. < 50 = 5.16, 95% CI = 2.59 - 10.29). Conclusion: Nulliparity and menopausal age of more than 50 years was associated with increased breast cancer risk. Breast feeding and age less than 25 years at first live birth was not protective against breast cancer. (author)

  16. Gut microbiota diversity and T1DM onset: Preliminary data of a case-control study

    Directory of Open Access Journals (Sweden)

    Deborah Traversi

    2017-12-01

    Full Text Available Type-1 diabetes incidence is increasing during the last decades. Recently, a role of microbiota alteration is proposed as pre-diabetic and diabetic risk factor. A bicentric case-control study is in progress in Northern Italy. Here preliminary results are shown. The microbiome clusterization showed a division between cases and controls even if fingerprint profiles are heterogenic. Methanobrevibacter smithii is highly present only in few patients. The diversity index and the microorganism sequenced in cases and controls, seems to be quite dissimilar. The conclusive results could show a significant predictive value for the bio-indicators evaluated. Keywords: Type 1 diabetes mellitus, Microbiota, Children, Methanobrevibacter smithii, qRT-PCR

  17. A case-control study of childhood brain tumors and fathers' hobbies: a Children's Oncology Group study.

    Science.gov (United States)

    Rosso, Andrea L; Hovinga, Mary E; Rorke-Adams, Lucy B; Spector, Logan G; Bunin, Greta R

    2008-12-01

    A comprehensive case-control study was conducted to evaluate parental risk factors for medulloblastoma (MB) and primitive neuroectodermal tumor (PNET). This analysis was conducted to evaluate associations between fathers' hobbies and risk of their children developing MB/PNET. The hobbies chosen for study were those with similar exposures as occupations associated with childhood cancers. Cases were 318 subjects under six years of age at diagnosis between 1991 and 1997 and registered with the Children's Cancer Group. An equal number of controls were selected through random digit dialing and individually matched to cases. In multivariate analyses, a significant association was seen for lawn care with pesticides [during pregnancy: odds ratio (OR) = 1.6, 95% confidence interval (CI): 1.0, 2.5; after birth: OR = 1.8, 95% CI: 1.2, 2.8] and a weak association was seen for stripping paint [during pregnancy: OR = 1.4, 95% CI: 0.8, 2.6; after birth: OR = 1.4, 95% CI: 0.7, 2.6]. This study suggests that household exposures from hobbies, particularly pesticides, may increase risk of MB/PNET in children; previous research has been mostly limited to occupational exposures.

  18. Putative periodontopathic bacteria and herpesviruses in pregnant women: a case-control study.

    Science.gov (United States)

    Lu, Haixia; Zhu, Ce; Li, Fei; Xu, Wei; Tao, Danying; Feng, Xiping

    2016-06-15

    Little is known about herpesvirus and putative periodontopathic bacteria in maternal chronic periodontitis. The present case-control study aimed to explore the potential relationship between putative periodontopathic bacteria and herpesviruses in maternal chronic periodontitis.Saliva samples were collected from 36 pregnant women with chronic periodontitis (cases) and 36 pregnant women with healthy periodontal status (controls). Six putative periodontopathic bacteria (Porphyromonas gingivalis [Pg], Aggregatibacer actinomycetemcomitans [Aa], Fusobacterium nucleatum [Fn], Prevotella intermedia [Pi], Tannerella forsythia [Tf], and Treponema denticola [Td]) and three herpesviruses (Epstein-Barr virus [EBV], human cytomegalovirus [HCMV], and herpes simplex virus [HSV]) were detected. Socio-demographic data and oral health related behaviors, and salivary estradiol and progesterone levels were also collected. The results showed no significant differences in socio-demographic background, oral health related behaviors, and salivary estradiol and progesterone levels between the two groups (all P > 0.05). The detection rates of included periodontopathic microorganisms were not significantly different between the two groups (all P > 0.05), but the coinfection rate of EBV and Pg was significantly higher in the case group than in the control group (P = 0.028). EBV and Pg coinfection may promote the development of chronic periodontitis among pregnant women.

  19. The relationship between maternal periodontitis and preterm low birth weight: A case-control study

    Directory of Open Access Journals (Sweden)

    Satheesh Mannem

    2011-01-01

    Full Text Available Background: The relationship between periodontal diseases in pregnancy and children born prematurely or with low birth weight has been increasingly investigated, showing positive and negative results, respectively. Objective: To evaluate the association between Maternal Periodontitis and Preterm delivery or Low Birth Weight. Materials and Methods: In this case-control study, 104 pregnant women without systemic disease or other risk factors for preterm labor were chosen. The control group (n = 52 had term labor (infants ≥37 weeks and the case group (n = 52 had preterm labor (infants <37 weeks. Plaque index, bleeding index, and birth weight were measured. Results: The data of plaque index (cases 1.21±0.56; controls 0.63±0.31, bleeding index (cases, 2.08±0.62; controls, 1.52±0.61, birth weight (cases, 2.01±0.36; controls 2.87±0.32, and Probing Pocket Depth (PPD ≥4mm and Clinical Attachment Level (CAL ≥3mm in at least 4 teeth (odds ratio 137.50, P value < 0.0001 revealed a statistically significant difference between the two groups P< 0.05. Conclusions: A noticeable relationship between periodontal health and duration of pregnancy; periodontal disease could be a risk factor for preterm labor. Oral hygiene maintenance should be a part of prenatal care protocol.

  20. Campylobacteriosis in New Zealand: results of a case-control study.

    Science.gov (United States)

    Eberhart-Phillips, J; Walker, N; Garrett, N; Bell, D; Sinclair, D; Rainger, W; Bates, M

    1997-12-01

    To identify and assess the contributions of major risk factors for campylobacteriosis in New Zealand. Case-control study. Home interviews were conducted over nine months using a standardised questionnaire to assess recent food consumption and other exposures. Four centres in New Zealand with high notification rates of campylobacter infections--Auckland, Hamilton, Wellington, and Christchurch. Case patients were 621 people notified between 1 June 1994 and 28 February 1995 as having campylobacter infection. Control subjects were selected randomly from telephone directories, and were matched 1:1 with case patients in relation to sex, age group, and home telephone prefix. Risk of campylobacteriosis was strongly associated with recent consumption of raw or undercooked chicken (matched odds ratio 4.52, 95% confidence interval 2.88, 7.10). There was also an increased risk with chicken eaten in restaurants (matched odds ratio 3.85; 2.52, 5.88). Recent consumption of baked or roasted chicken seemed to be protective. Campylobacteriosis was also associated with recent overseas travel, rainwater as a source of water at home, consumption of raw dairy products, and contact with puppies and cattle, particularly calves. Improperly cooked chicken seems to be associated with a large proportion of campylobacteriosis in New Zealand. Thorough cooking of chicken in homes and restaurants could reduce considerably the incidence of this disease.

  1. Optimized Real-Time Control of Combined Sewerage Systems: Two Case Studies (Proceedings Paper)

    Science.gov (United States)

    The paper presents results of two case studies of Real-Time Control (RTC) alternatives evaluations that were conducted on portions of sewerage systems near Paris, France and in Quebec City, Canada, respectively. The studies were performed at real-scale demonstration sites. RTC al...

  2. Tularemia Outbreak Investigation in Kosovo: Case Control and Environmental Studies

    Science.gov (United States)

    Dedushaj, Isuf; Gjini, Ardiana; Jorgensen, Tine Rikke; Cotter, Benvon; Lieftucht, Alfons; D’Ancona, Fortunato; Dennis, David T.; Kosoy, Michael A.; Mulliqi-Osmani, Gjyle; Grunow, Roland; Kalaveshi, Ariana; Gashi, Luljeta; Humolli, Isme

    2002-01-01

    A large outbreak of tularemia occurred in Kosovo in the early postwar period, 1999-2000. Epidemiologic and environmental investigations were conducted to identify sources of infection, modes of transmission, and household risk factors. Case and control status was verified by enzyme-linked immunosorbent assay, Western blot, and microagglutination assay. A total of 327 serologically confirmed cases of tularemia pharyngitis and cervical lymphadenitis were identified in 21 of 29 Kosovo municipalities. Matched analysis of 46 case households and 76 control households suggested that infection was transmitted through contaminated food or water and that the source of infection was rodents. Environmental circumstances in war-torn Kosovo led to epizootic rodent tularemia and its spread to resettled rural populations living under circumstances of substandard housing, hygiene, and sanitation. PMID:11749751

  3. European multi-centre case-control study on risk factors for rare cancers of unknown aetiology

    DEFF Research Database (Denmark)

    Lynge, Elsebeth; Afonso, Noemia; Kaerlev, Linda

    2005-01-01

    To search for occupational risk factors, we conducted a case-control study in nine European countries of cancers of the small intestine, male gall bladder, thymus, bone, male breast, melanoma of the eye, and mycosis fungoides. Recruitment was population based in Denmark, Latvia, France, Germany...... recruited 3374 population (61% interviewed) and 1284 colon cancer controls (86% interviewed). It was possible to undertake this complicated study across Europe, but we encountered three main problems. It was difficult to ensure complete case ascertainment, for population controls, we found a clear divide......, Italy, and Sweden, from hospital areas in Spain and Portugal, and from one United Kingdom (UK) hospital. We recruited 1457 cases (84% interviewed). Numbers identified corresponded to those in the EUROCIM database for Denmark, but were below those observed for France, Italy and Sweden in the database. We...

  4. The risk of menstrual abnormalities after tubal sterilization: a case control study

    Directory of Open Access Journals (Sweden)

    AtashKhoii Simin

    2005-05-01

    Full Text Available Abstract Background Tubal sterilization is the method of family planning most commonly used. The existence of the post-tubal-ligation syndrome of menstrual abnormalities has been the subject of debate for decades. Methods In a cross-sectional study, 112 women with the history of Pomeroy type of tubal ligation achieved by minilaparatomy as the case group and 288 women with no previous tubal ligation as the control group were assessed for menstrual abnormalities. Results Menstrual abnormalities were not significantly different between the case and control groups (p = 0.824. The abnormal uterine bleeding frequency differences in two different age groups (30–39 and 40–45 years old were statistically significant (p = 0.0176. Conclusion Tubal sterilization does not cause menstrual irregularities.

  5. Use of oral cholera vaccines in an outbreak in Vietnam: a case control study.

    Directory of Open Access Journals (Sweden)

    Dang Duc Anh

    Full Text Available BACKGROUND: Killed oral cholera vaccines (OCVs are available but not used routinely for cholera control except in Vietnam, which produces its own vaccine. In 2007-2008, unprecedented cholera outbreaks occurred in the capital, Hanoi, prompting immunization in two districts. In an outbreak investigation, we assessed the effectiveness of killed OCV use after a cholera outbreak began. METHODOLOGY/PRINCIPAL FINDINGS: From 16 to 28 January 2008, vaccination campaigns with the Vietnamese killed OCV were held in two districts of Hanoi. No cholera cases were detected from 5 February to 4 March 2008, after which cases were again identified. Beginning 8 April 2008, residents of four districts of Hanoi admitted to one of five hospitals for acute diarrhea with onset after 5 March 2008 were recruited for a matched, hospital-based, case-control outbreak investigation. Cases were matched by hospital, admission date, district, gender, and age to controls admitted for non-diarrheal conditions. Subjects from the two vaccinated districts were evaluated to determine vaccine effectiveness. 54 case-control pairs from the vaccinated districts were included in the analysis. There were 8 (15% and 16 (30% vaccine recipients among cases and controls, respectively. The vaccine was 76% protective against cholera in this setting (95% CI 5% to 94%, P = 0.042 after adjusting for intake of dog meat or raw vegetables and not drinking boiled or bottled water most of the time. CONCLUSIONS/SIGNIFICANCE: This is the first study to explore the effectiveness of the reactive use of killed OCVs during a cholera outbreak. Our findings suggest that killed OCVs may have a role in controlling cholera outbreaks.

  6. A case-control study of visual acuity in onychocryptosis.

    LENUS (Irish Health Repository)

    Hogan, Aisling M

    2012-02-01

    BACKGROUND: There are many theories surrounding the etiology of ingrown toenails (IGTN). Few factors have been formally assessed, but it is widely accepted that a poor nail cutting technique has a causative role. AIM: To investigate the hypothesis that decreased visual acuity may lead to inadequate nail cutting and the formation of IGTN. METHODS: A prospective case-control study was performed. Near and distance visual acuity were tested on a population with IGTN (n = 19) and compared with that of an age- and sex-matched control cohort (n = 24) who underwent epidermal cyst excision in the same tertiary referral center. Comparisons of visual acuity were made between groups by Mann-Whitney U-test. Differences were taken to be significant if P < 0.05. Institutional Review Board approval was sought and granted. RESULTS: No significant difference in visual acuity (near or distance) was demonstrated between patients with IGTN and the control group (P = 0.33). CONCLUSION: Visual acuity does not appear to play a significant role in the development of IGTN.

  7. The relationship between parenting, family interaction and childhood dental caries: a case-control study

    NARCIS (Netherlands)

    de Jong-Lenters, M.; Duijster, D.; Bruist, M.A.; Thijssen, J.; de Ruiter, C.

    2014-01-01

    The aim of this case-control study was to explore the relationship between parenting practices, parent-child interaction and childhood dental caries, using a sample of 5-8-year old children from the Netherlands. Cases were defined as children with four or more decayed, missing or filled teeth and

  8. The relationship between parenting, family interaction and childhood dental caries: A case-control study

    NARCIS (Netherlands)

    Jong-Lenters, M. de; Duijster, D.; Bruist, M.A.; Thijssen, J.; Ruiter, C. de

    2014-01-01

    The aim of this case-control study was to explore the relationship between parenting practices, parent-child interaction and childhood dental caries, using a sample of 5-8-year old children from the Netherlands. Cases were defined as children with four or more decayed, missing or filled teeth and

  9. Low maternal folate concentrations and maternal MTHFR C677T polymorphism are associated with an increased risk for neural tube defects in offspring: a case-control study among Pakistani case and control mothers.

    Science.gov (United States)

    Nauman, Nuzhat; Jalali, Samina; Shami, Sajjad; Rafiq, Shireen; Große, Greta; Hilger, Alina C; Zhang, Rhong; Mansoor, Saira; Ludwig, Michael; Reutter, Heiko

    2018-01-01

    There is considerable evidence that periconceptional maternal folate deficiency and coding variants in maternal genes coding for critical enzymes in the folate pathway are associated with neural tube defects (NTDs) in offspring. In a case-control study we investigated C677T polymorphism in the 5,10- methylenetetrahydrofolate reductase (MTHFR) gene in case and control mothers of Pakistani origin, and compared these with the respective maternal folate concentrations measured at the time of delivery. A case-control study was conducted among 109 case and 100 control mothers identified through the Holy Family Hospital Rawalpindi, Quaid-i-Azam University, Islamabad, Pakistan. Red blood cell (RBC) and serum folate concentrations and MTHFRC677T polymorphism were compared between case and control mothers. Mean RBC folate and serum folate concentrations were significantly lower in cases compared with control mothers (pcases compared with control mothers (CC vs TT pcases compared with control mothers (C vs T pCase mothers with 677CT or 677TT genotypes had significantly lower serum (pstudy provides further evidence that maternal folate deficiency and MTHFRC677T polymorphism might be associated with an increased risk for NTDs in offspring. Our results are limited by the fact that maternal folate concentrations were not obtained during the periconceptional period, but at delivery. Further analyses, including maternal folate levels during the periconceptional period, are warranted.

  10. Placental vascular complications in HIV-infected pregnant women: a case-control study

    OpenAIRE

    CANLORBE, Geoffroy

    2012-01-01

    Background: Data from international literature suggest a link between HIV infection and placental vascular complications during pregnancy. Current studies on the subject are conflicting.Objective: The aim of the study was to evaluate the incidence of placental vascular complications during pregnancy among HIV+ and HIV- patients.Study Design: It is a single-center case-control study comparing the rates of gestational hypertension, preeclampsia, eclampsia and vascular intrauterine growth retard...

  11. Case-control study of pleural mesothelioma in workers with social security in Mexico.

    Science.gov (United States)

    Aguilar-Madrid, Guadalupe; Robles-Pérez, Eduardo; Juárez-Pérez, Cuauhtémoc Arturo; Alvarado-Cabrero, Isabel; Rico-Méndez, Flavio Gerardo; Javier, Kelly-García

    2010-03-01

    Environmental and occupational exposure to asbestos in Mexico in the past has been a cause of deaths and health damages. Its magnitude is unknown to date. Our objective was to identify the proportion of cases of malignant pleural mesothelioma (MPM) that can be attributed to and occupational exposure to asbestos. We carried out a case-control study of MPM in 472 workers insured by the Mexican Institute of Social Security, all Valley of Mexico residents, with 119 incident cases and 353 controls. Cases were histologically confirmed. Participants were questioned concerning their occupational history and sociodemographic data. Assignment to one of the four exposures was performed qualitatively by an expert hygienist. Odds ratios (ORs) and attributable risks (ARs) were calculated using a non-conditional logistic regression model. A total of 80.6% of cases and 31.5% of controls had occupational exposure to asbestos. ORs were adjusted for age and gender and by exposure category, and exhibited an increase with probability of exposure as follows: 3.7(95% CI 1.3-10.4) for the likely category and 14.3(95% CI 8-26) for the certain category; AR in the group occupationally exposed to asbestos was 83.2%, and the population AR was 44%. Our results show that the relationship between industrial uses of all forms of asbestos is generating an increase in mesothelioma-related diseases and deaths among Mexican workers. As a public health policy, Mexico should prohibit the use of asbestos in all production processes with the aim of controlling the epidemic and preventing the occurrence of new cases of MPM. 2009 Wiley-Liss, Inc.

  12. Psychogenic nonepileptic seizures and chronic pain: a retrospective case-controlled study.

    Science.gov (United States)

    Gazzola, Deana M; Carlson, Chad; Rugino, Angela; Hirsch, Scott; Starner, Karen; Devinsky, Orrin

    2012-12-01

    Psychogenic nonepileptic seizures (PNES) can be challenging to diagnose, but certain clinical features can help to distinguish PNES from epileptic seizures. The purpose of this study is to assess chronic pain and prescribed pain medication use in PNES patients. A case-controlled, retrospective analysis was performed examining pain medication use in 85 PNES patients versus an active control group of 85 patients with idiopathic generalized epilepsy (IGE). Chronic pain was more frequent among PNES patients (N=40) than active controls (N=10) (pseizures raises the possibility of PNES. Among patients with PNES and chronic pain, a psychogenic etiology for pain and non-opiate pain management strategies should be considered. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Residential traffic noise exposure and vestibular schwannoma - a Danish case-control study.

    Science.gov (United States)

    Roswall, Nina; Stangerup, Sven-Eric; Cayé-Thomasen, Per; Schüz, Joachim; Johansen, Christoffer; Jensen, Steen Solvang; Raaschou-Nielsen, Ole; Sørensen, Mette

    2017-10-01

    Few risk factors for sporadic vestibular schwannoma (VS) are known. Several studies have proposed an increased risk with occupational noise exposure, whereas no studies have investigated residential traffic noise exposure as a risk factor. The present study investigated if residential traffic noise was associated with vestibular schwannoma in a large, population-based Danish case-control study. We identified 1454 VS cases, age above 30 years at diagnosis, between 1990 and 2007. For each case, we selected two random population controls, matched on sex and year of birth. Road and railway traffic noise at the residence was calculated for all present and historical addresses between 1987 and index date. Associations between traffic noise and risk for VS were estimated using conditional logistic regression, adjusted for education, disposable personal income, cohabitation status, railway noise exposure, municipal population density, and municipal income. A two-year time-weighted mean road traffic noise exposure was associated with an adjusted odds ratio of 0.92 (0.82-1.03) for developing VS, per 10 dB increment. There was no clear trend in categorical analyses. Similarly, linear and categorical analyses of residential railway noise did not suggest an association. We found no interaction with demographics, year of diagnosis, individual and municipal socioeconomic variables, and railway noise exposure. The results did not differ by tumor side, spread or size. The present study does not suggest an association between residential traffic noise and VS.

  14. DNA fingerprinting: a quality control case study for human biospecimen authentication.

    Science.gov (United States)

    Kofanova, Olga A; Mathieson, William; Thomas, Gerry A; Betsou, Fotini

    2014-04-01

    This case study illustrates the usefulness of the DNA fingerprinting method in biobank quality control (QC) procedures and emphasizes the need for detailed and accurate record keeping during processing of biological samples. It also underlines the value of independent third-party assessment to identify points at which errors are most likely to have occurred when unexpected results are obtained from biospecimens.

  15. Case-control study of cancer deaths in high background radiation areas of China

    International Nuclear Information System (INIS)

    Tao Zufan; Cha Yongru; Zhou Shunyuan

    1989-01-01

    This paper presents the results of a case-control study of deaths from liver, stomach and lung cancers in the high background radiation areas (HBRA) in Yangjiang County and neighboring control areas (CA). The purpose of this study was to explore the probable relationship between the cancer deaths and the environmental mutation-related factors in the two areas, so that the role of elevated natural radiation in cancer mortality could be properly ascertained. The studied numbers of cases of liver, stomach and lung cancers were 64, 28 and 17 in HBRA, and 75, 36 and 13 in CA, respectively. The proportion of the number of cases to that of the controls was 1:1 for liver cancer and 1:2 for cancers of stomach and lung. The factors studied included pesticide, smoking, alcohol consumption, medical X-ray exposure, diet, and the socioeconomic status, such as occupation, education, economic income, living space etc. The data for this study were collected through interviewing. The data collected were analysed by methods of matched and unmatched studies. The results expressed by odds ratio (OR) show that there is no significant between most factors studied and cancer deaths, although the associations of desths from stomach cancer with drinking water of nonwell source and of lung cancer with alcohol consumption in HBRA, and the associations of liver cancer deaths with occupations involving poisonous and noxious substances, pesticide and alcohol, and of lung cancer with pesticide and lower family income in CA can be found. This study has provided some clues for explaining the difference in cancer mortalities between HBRA and CA

  16. Associated factors with attention deficit hyperactivity disorder (ADHD): a case-control study.

    Science.gov (United States)

    Malek, Ayyoub; Amiri, Shahrokh; Sadegfard, Majid; Abdi, Salman; Amini, Saeedeh

    2012-09-01

    The current study attempted to investigate factors associated with attention deficit hyperactivity disorder (ADHD) in children without co-morbidities. In this case-control study, 164 ADHD children who attended the Child and Adolescent Psychiatric Clinics of Tabriz University of Medical Sciences, Iran were compared with 166 normal children selected in a random-cluster method from primary and secondary schools. Clinical interviews based on DSM-IV-TR using K-SADS were used to diagnose ADHD cases and to select the control group. Participants were matched for age. We used chi-square and binary logistic regression for data analysis. Among the associated factors with ADHD were gender and maternal employment. Boys (OR 0.54; 95% confidence interval: 0.34 - 0.86) and those children with working mothers (OR 0.16: 95% confidence interval: 0.06 - 0.86) suffered more from ADHD. The birth season, family size, birth order, and parental kinship were not among risk factors for ADHD. The results of the study show that maternal employment and male gender are among the associated risk factors for ADHD.

  17. Screening for impulse control symptoms in patients with de novo Parkinson disease: a case-control study.

    Science.gov (United States)

    Weintraub, Daniel; Papay, Kimberly; Siderowf, Andrew

    2013-01-08

    To determine the frequency and correlates of impulse control and related behavior symptoms in patients with de novo, untreated Parkinson disease (PD) and healthy controls (HCs). The Parkinson's Progression Markers Initiative is an international, multisite, case-control clinical study conducted at 21 academic movement disorders centers. Participants were recently diagnosed, untreated PD patients (n = 168) and HCs (n = 143). The outcome measures were presence of current impulse control and related behavior symptoms based on recommended cutoff points for the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease (QUIP)-Short Form. There were 311 participants with complete QUIP data. Frequencies of impulse control and related behavior symptoms for patients with PD vs HCs were as follows: gambling (1.2% vs. 0.7%), buying (3.0% vs. 2.1%), sexual behavior (4.2% vs. 3.5%), eating (7.1% vs. 10.5%), punding (4.8% vs. 2.1%), hobbyism (5.4% vs. 11.9%), walkabout (0.6% vs. 0.7%), and any impulse control or related behavior (18.5% vs. 20.3%). In multivariable models, a diagnosis of PD was not associated with symptoms of any impulse control or related behavior (p ≥ 0.10 in all cases). PD itself does not seem to confer an increased risk for development of impulse control or related behavior symptoms, which further reinforces the reported association between PD medications and impulse control disorders in PD. Given that approximately 20% of patients with newly diagnosed PD report some impulse control or related behavior symptoms, long-term follow-up is needed to determine whether such patients are at increased risk for impulse control disorder development once PD medications are initiated.

  18. Malaria control in Bhutan: case study of a country embarking on elimination

    Directory of Open Access Journals (Sweden)

    Yangzom Thinley

    2012-01-01

    Full Text Available Abstract Background Bhutan has achieved a major reduction in malaria incidence amid multiple challenges. This case study seeks to characterize the Bhutan malaria control programme over the last 10 years. Methods A review of the malaria epidemiology, control strategies, and elimination strategies employed in Bhutan was carried out through a literature review of peer-reviewed and grey national and international literature with the addition of reviewing the surveillance and vector control records of the Bhutan Vector-Borne Disease Control Programme (VDCP. Data triangulation was used to identify trends in epidemiology and key strategies and interventions through analysis of the VDCP surveillance and programme records and the literature review. Enabling and challenging factors were identified through analysis of socio-economic and health indicators, corroborated through a review of national and international reports and peer-review articles. Findings Confirmed malaria cases in Bhutan declined by 98.7% from 1994 to 2010. The majority of indigenous cases were due to Plasmodium vivax (59.9% and adult males are most at-risk of malaria. Imported cases, or those in foreign nationals, varied over the years, reaching 21.8% of all confirmed cases in 2006. Strategies implemented by the VDCP are likely to be related to the decline in cases over the last 10 years. Access to malaria diagnosis in treatment was expanded throughout the country and evidence-based case management, including the introduction of artemisinin-based combination therapy (ACT for P. falciparum, increasing coverage of high risk areas with Indoor Residual Spraying, insecticide-treated bed nets, and long-lasting insecticidal nets are likely to have contributed to the decline alongside enabling factors such as economic development and increasing access to health services. Conclusion Bhutan has made significant strides towards elimination and has adopted a goal of national elimination. A major

  19. Symptoms and sources of Yersinia enterocolitica-infection: a case-control study

    Directory of Open Access Journals (Sweden)

    Siitonen Anja

    2010-05-01

    Full Text Available Abstract Background Yersinia enterocolitica (YE is the causative agent of yersiniosis. YE encompass strains of diverse pathogenicity: YE biotypes 1B and 2-5 are considered pathogenic, whereas biotype 1A is in general considered nonvirulent. Also YE-like species, which can sometimes be misidentified as YE, are considered nonvirulent. Methods In order to study differences in clinical picture caused by different YE types and their possible sources a case-control study was conducted in 2006. In this case-control study, 295 case-patients with YE or YE-like finding and their 758 controls responded to the questionnaire about symptoms and possible sources of infection. Results Strains of pathogenic YE bio/serotypes 3-4/O:3 or 2/O:9 were found in 18%, YE biotype 1A in 65% and YE -like strains of 17% of the patients. Patients infected with the strains of pathogenic YE bio/serotypes were younger and had fever more often than those with BT 1A who suffered more from vomiting. Symptoms of reactive arthritis were reported by 10% of pathogenic YE infections, 3% of YE BT 1A, and 0.3% of the controls. Eating or tasting raw or medium done pork was a significant risk factor for pathogenic YE bio/serotype infection (OR 6.6; 95% CI 1.7-24.9 as well as eating in a canteen (OR 3.5; 95% CI 1.6-7.9. Imported fruits and berries were associated with increased risk of YE BT 1A finding. Conclusions The symptoms of the patients with YE BT 1A differed from yersiniosis caused by the classic pathogenic YE bio/serotypes. In addition, the patients with YE BT 1A had more protracted gastrointestinal disorders and unspecific complaints. Small children were overrepresented in classic pathogenic bio/serotypes while in BT 1A or YE-like species were not found among children younger than two years. This suggests the lacking virulence of the BT 1A strains. We can not, however, rule out the possibility that some strains of genetically heterogeneous group of BT 1A may cause an illness.

  20. Mobile phone base stations and early childhood cancers: case-control study.

    Science.gov (United States)

    Elliott, Paul; Toledano, Mireille B; Bennett, J; Beale, L; de Hoogh, K; Best, N; Briggs, D J

    2010-06-22

    To investigate the risk of early childhood cancers associated with the mother's exposure to radiofrequency from and proximity to macrocell mobile phone base stations (masts) during pregnancy. Case-control study. Cancer registry and national birth register data in Great Britain. 1397 cases of cancer in children aged 0-4 from national cancer registry 1999-2001 and 5588 birth controls from national birth register, individually matched by sex and date of birth (four controls per case). Incidence of cancers of the brain and central nervous system, leukaemia, and non-Hodgkin's lymphomas, and all cancers combined, adjusted for small area measures of education level, socioeconomic deprivation, population density, and population mixing. Mean distance of registered address at birth from a macrocell base station, based on a national database of 76,890 base station antennas in 1996-2001, was similar for cases and controls (1107 (SD 1131) m v 1073 (SD 1130) m, P=0.31), as was total power output of base stations within 700 m of the address (2.89 (SD 5.9) kW v 3.00 (SD 6.0) kW, P=0.54) and modelled power density (-30.3 (SD 21.7) dBm v -29.7 (SD 21.5) dBm, P=0.41). For modelled power density at the address at birth, compared with the lowest exposure category the adjusted odds ratios were 1.01 (95% confidence interval 0.87 to 1.18) in the intermediate and 1.02 (0.88 to 1.20) in the highest exposure category for all cancers (P=0.79 for trend), 0.97 (0.69 to 1.37) and 0.76 (0.51 to 1.12), respectively, for brain and central nervous system cancers (P=0.33 for trend), and 1.16 (0.90 to 1.48) and 1.03 (0.79 to 1.34) for leukaemia and non-Hodgkin's lymphoma (P=0.51 for trend). There is no association between risk of early childhood cancers and estimates of the mother's exposure to mobile phone base stations during pregnancy.

  1. Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

    Science.gov (United States)

    Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

    2016-01-05

    Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

  2. Factors associated with voice disorders among teachers: a case-control study.

    Science.gov (United States)

    Giannini, Susana Pimentel Pinto; Latorre, Maria do Rosário Dias de Oliveira; Ferreira, Léslie Piccolotto

    2013-01-01

    We aimed at verifying an association between voice disorders/stress and loss of work ability among female teachers who work in São Paulo's public school system. This is a paired case- control study. The case group was composed offiteachers with alterations in speech and larynges assessments, and the control group was formed by teachers without alterations in these evaluations who work in the same schools. Both groups answered the following questionnaires: Conditions of Vocal Production-Teachers, Job Stress Scale, and Work Ability Index. The analysis was performed using the chi-square association test and logistic regression models with the purpose of estimating the association between independent variables and voice disorders. We found differences between the groups in relation to stress in the workplace under high demand, a situation that poses greater risks of adverse reactions to the workers' physical and mental health. Regarding the ability to work, the categories poor and moderate ability for work are associated with voice disorders, regardless of job stress factors, age, and the unsatisfactory acoustic properties of the classrooms. This study confirmed the association between voice disorders and job stress, as well as between voice disorders and loss of work ability.

  3. Severe obesity, emotions and eating habits: a case-control study.

    Science.gov (United States)

    Koski, M; Naukkarinen, H

    2017-01-01

    Obesity has a multifaceted etiology that involves genetic, biological and behavioral factors, body growth, eating habits, energy expenditure and the function of adipose tissue. The present study aimed to expand upon knowledge about the relationships among obesity, emotions and eating habits in severely obese individuals using a case-control method. The subject group consisted of 112 individuals (81 females and 31 males) receiving a permanent disability pension primarily for obesity. The control subjects were randomly selected from the same area and were receiving a disability pension for a different primary illness. The controls were matched with the subjects by the place of residence, sex, age, the time since the pension was granted and occupation. Psychiatric interviews were conducted on all participants. The results were analyzed using the chi-squared test (χ 2 -test) and the percent distribution. The subject and control groups were compared using the t-test for paired variables. Conditional logistic regression analysis was also conducted. The emotional state of eating was significantly associated with quarrels and feelings of loneliness. The subjects suffered from night eating syndrome, which was associated with an increased risk of early retirement. Binge eating syndrome was observed more frequently in the study group. The subjects reported feeling increased hunger compared with the controls. A significant percentage of the subjects had a body mass index of ≥ 40. No differences in eating habits were observed between the groups. This study provides information on the relationship between emotions and eating habits in obesity, which is a rarely studied topic. We believe that our study provides a novel and necessary overview of the associations among severe obesity, emotions and eating habits.

  4. Non-nutritive sucking habits after three years of age: A case-control study

    Directory of Open Access Journals (Sweden)

    Izabella Barbosa Fernandes

    2015-01-01

    Full Text Available Background: Non-nutritive sucking habits can result in negative consequences on the development of orofacial structures and occlusion. Aim: Assess factors associated with non-nutritive sucking habits in children after 3 years old. Materials and Methods: A case-control study was carried out in two stages. In the first stage, a cross-sectional study was conducted with 638 children aged 3-6 years. In the second stage, a case-control study (1:2 was conducted. The case group included all children who presented some non-nutritive sucking habits in the first stage of the study (n = 110. The control group (n = 220 was made up of children who had never presented non-nutritive sucking habits, matched to the case group for gender and age. The data were collected during the national poliomyelitis vaccination campaign, through a questionnaire applied to parents/guardians with questions related to the presence of sucking habits, sociodemographic aspects, birth aspects, and early life of the child. Statistical analysis involved descriptive analysis, chi-square test, Mann-Whitney test, and conditional logistic regression. Results: Reduction in maternal education was a protective factor for the development of non-nutritive sucking habits (education ≤8 years OR = 0.38, CI 95%: 0.16, 0.89, P = 0.025. Prematurity (OR = 3.30, CI 95%: 1.13, 9.69, P = 0.030 and a longer period using a baby bottle (OR = 1.03, CI 95%: 1.01, 1.05, P = 0.006 remained associated with a greater possibility of the occurrence of sucking habits, regardless of monthly family income. Conclusion: Non-nutritive sucking habits were associated with maternal education, premature birth, and greater time of bottle feeding in children after 3 years old.

  5. Risk factors for posterior vitreous detachment: a case-control study.

    Science.gov (United States)

    Chuo, Jean Y; Lee, Tracy Y Y; Hollands, Hussein; Morris, Andrew H; Reyes, Romina C; Rossiter, Jonathan D; Meredith, Sarah P; Maberley, David A L

    2006-12-01

    To identify possible risk factors for the development of posterior vitreous detachment (PVD). Retrospective case-control study. A total of 138 cases with PVD and 114 age-matched controls were accrued from two different sites. Demographic, medical, ocular, and lifestyle data were obtained through chart review, questionnaires, and clinical examination. A 108-item semiquantitative food frequency questionnaire was also used to estimate macro- and micronutrient intake. Univariate and multivariate regression analyses were employed to identify variables significantly associated with the main outcome measure of PVD. Subgroup analysis of gender-specific variables was performed. Among all patients, multivariate regression analysis demonstrated female gender (odds ratio [OR] = 2.01, P = .016), myopic refraction (OR = 4.32, P < .0005), and higher intake of vitamin B6 (OR = 2.61, P = .001) to be associated with PVD after controlling for age. In the subgroup analysis of women, menopause (OR = 18.2, P < .0005), myopic refraction (OR = 3.42, P = .01), and higher intake of vitamin B6 (OR = 3.92, P = .005) were associated with PVD. Specifically, there was a significant association between vitamin B6 and PVD amongst premenopausal women but not amongst postmenopausal women. An association between PVD and menopause has not been documented previously. We suspect that high estrogen levels seen in premenopausal women may be protective against PVD and that hormonal changes associated with menopause may lead to changes in the vitreous, predisposing to PVD. Higher levels of intake of vitamin B6 were also associated with the development of PVD in premenopausal women possibly through an anti-estrogen effect. These findings should be investigated further with prospective studies.

  6. Sympathetic skin response in multiple sclerosis: a meta-analysis of case-control studies.

    Science.gov (United States)

    Margaritella, Nicolò; Mendozzi, Laura; Garegnani, Massimo; Gilardi, Elisabetta; Nemni, Raffaello; Pugnetti, Luigi

    2018-01-01

    The usefulness of sympathetic skin responses (SSR) in multiple sclerosis (MS) has been advocated by several studies in the last 20 years; however, due to a great heterogeneity of findings, a comprehensive meta-analysis of case-control studies is in order to pinpoint consistencies and investigate the causes of discrepancies. We searched MEDLINE, EMBASE and Cochrane databases for case-control studies comparing SSR absence frequency and latency between patients with MS and healthy controls. Thirteen eligible studies including 415 MS patients and 331 healthy controls were identified. The pooled analysis showed that SSR can be always obtained in healthy controls while 34% of patients had absent SSRs in at least one limb (95% CI 22-47%; p studies (I 2  = 90.3%). Patients' age explained 22% of the overall variability and positive correlations were found with Expanded Disability Status Scale and disease duration. The pooled mean difference of SSR latency showed a significant increase in patients on both upper (193 ms; 95% CI 120-270 ms) and lower (350 ms; 95% CI 190-510 ms) extremities. We tested the discriminatory value of SSR latency thresholds defined as the 95% confidence interval (CI) upper bound of the healthy controls, and validated the results on a new dataset. The lower limb threshold of 1.964 s produces the best results in terms of sensitivity 0.86, specificity 0.67, positive predicted value 0.75 and negative predicted value 0.80. Despite a considerable heterogeneity of findings, there is evidence that SSR is a useful tool in MS.

  7. Perceived stress in patients with migraine: a case-control study.

    Science.gov (United States)

    Moon, Hye-Jin; Seo, Jong-Geun; Park, Sung-Pa

    2017-12-01

    Perceived stress is the most common trigger for migraine. The objective of this study was to examine the clinical significance of perceived stress in migraine patients. This is a case-control study. Consecutive migraine patients who visited a tertiary care hospital were enrolled for this study. They completed self-reported questionnaires including Perceived Stress Scale (PSS), 12-item Allodynia Symptom Checklist (ASC-12), Migraine Disability Assessment Scale (MIDAS), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), and Migraine-Specific Quality of Life Questionnaire (MSQ). Degree of perceived stress in migraine patients was measured and compared to that in healthy controls. Predictors for perceived stress and their impact on quality of life (QOL) of migraine patients were also determined. A total of 227 migraine patients were eligible for this study, including 103 (45.4%) who had chronic migraine (CM). Mean PSS score was significantly (p migraine is a critical factor for perceived stress. Perceived stress affects QOL of migraine patients.

  8. Exposure to antiepileptic drugs and the risk of hip fracture: a case-control study

    DEFF Research Database (Denmark)

    Tsiropoulos, Ioannis; Andersen, Morten; Nymark, Tine

    2008-01-01

    PURPOSE: To investigate whether the use of antiepileptic drugs (AEDs) increases the risk of hip fracture. METHODS: We performed a case-control study using data from the Funen County (population 2004: 475,000) hip fracture register. Cases (n = 7,557) were all patients admitted to county hospitals...... with a hip fracture during the period 1996-2004. Controls (n = 27,575) were frequency matched by age and gender. Information on use of AEDs, other drugs, and hospital contacts was available from local registers. Odds ratios (ORs) with 95% confidence intervals (CI) for hip fracture were estimated...

  9. Symptoms of non-gonococcal urethritis in heterosexual men: a case control study.

    Science.gov (United States)

    Iser, P; Read, Tr H; Tabrizi, S; Bradshaw, C; Lee, D; Horvarth, L; Garland, S; Denham, I; Fairley, C K

    2005-04-01

    To determine microbial and behavioural factors contributing to non-gonococcal urethral symptoms in men. Case-control study of heterosexual men with non-gonococcal urethral symptoms (cases) and without urethral symptoms (controls) attending Melbourne Sexual Health Centre, Australia. Sexual behaviour and condom use were measured by questionnaire. First stream urine was tested for potential pathogens: Chlamydia trachomatis (ligase chain reaction), Mycoplasma genitalium (polymerase chain reaction, PCR), Ureaplasma urealyticum (culture and PCR), and Streptococcus spp, Gardnerella vaginalis, and Haemophilus species (culture). Urethral smears from cases were examined for polymorphonuclear leucocytes. 80 cases and 79 controls were recruited over 4 months in 2002-3. 49 cases (61%) had urethritis by microscopic criteria, 17 (21%) had Chlamydia trachomatis (adjusted odds ratio (OR) 27 (95% confidence interval (CI): 3.4 to 222)), five (6%) had Mycoplasma genitalium (OR 6.1 (95% CI: 0.6 to 61)), and 11 (14%) had Gardnerella vaginalis (OR 9.0 (95% CI: 1.6 to 52)). Other organisms were not significantly associated with urethral symptoms. The presence of urethritis on urethral smear did not predict the presence of Chlamydia trachomatis (OR 1.7 (95% CI: 0.5 to 5.4)). Urethral symptoms were significantly associated with unprotected vaginal sex with more than one casual partner (OR 9.3 (95% CI: 1.3 to 65)) and unprotected anal sex with a regular partner in the past month (OR 3.5 (95% CI: 1.0 to 13)). Gardnerella vaginalis and unprotected anal sex may cause symptoms of non-gonococcal urethritis. Microscopy of the urethral smear to diagnose urethritis in this population does not help to identify which men with urethral symptoms require treatment for chlamydia.

  10. Radiotherapy- and chemotherapy-induced myelodysplasia syndrome: a nationwide population-based nested case-control study.

    Science.gov (United States)

    Sun, Li-Min; Lin, Cheng-Li; Lin, Ming-Chia; Liang, Ji-An; Kao, Chia-Hung

    2015-05-01

    This study explored which kinds of cancer are related to a higher incidence of subsequent myelodysplastic syndrome (MDS) after radiotherapy (RT) and chemotherapy (CT).We performed a nested case-control study by using data from the Taiwanese National Health Insurance (NHI) system. The case group included cancer patients who developed MDS. For the control group, 4 cancer patients without MDS were frequency-matched with each MDS case by age, sex, year of cancer diagnosis, and MDS index year. A multivariable logistic regression analysis was conducted, and odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.Overall, cancer patients who received RT or CT exhibited secondary MDS more frequently than did those who did not (RT: OR = 1.53; 95% CI = 1.33-1.77; CT: OR = 1.51; 95% CI = 1.25-1.82). Analysis by cancer site showed that RT increased the risk of MDS for patients with stomach, colorectal, liver, breast, endometrial, prostate, and kidney cancers. By contrast, CT was more likely to increase the risk of MDS for patients with lung, endometrial, and cervical cancers. Further analysis revealed that RT and CT seemed to have a positive interaction. The major limitation of this study was the lack of certain essential data in the NHI Research Database, such as data regarding cancer stage and treatment dose details.This population-based nested case-control study determined that RT and CT predisposed patients in Taiwan to the development of MDS. This effect was more prominent when both modalities were used.

  11. Behavioral Problems in Iranian Epileptic Children; A Case Control Study

    Directory of Open Access Journals (Sweden)

    Maryam Aludari

    2017-12-01

    Full Text Available Background Epilepsy is among the most common neurological disorders in childhood, prevalence of which is increasing. Unpredictable and chronic nature of the disease affects physical, social and mental functions of the children and their family. This study was aimed to compare behavioral problems in epileptic children group versus healthy control group. Materials and Methods This study is a case-control one conducted from January 2013 to June 2016 in Tehran, Iran. The epileptic children in age of 7-10 years old that were diagnosed by neurologist referred to the researcher for further process. Their parents were provided with Child Behavior Checklist (CBCL to be completed. For matching by age and gender, the healthy group was sampled after the epilepsy group. Multivariate Analysis of Variance was used for statistical analysis. Results In this study 94 children with epilepsy and 83 healthy children in age of 7-10 years old were studied. The results indicated that there were significantly higher behavioral problems in the children with epilepsy than in control group in nine categories of seclusiveness, physical complaints, anxiety and depression, social problems, thought problems, attention problems, delinquent behaviors, aggressive behaviors, and other problems. Comparison of two generalized and partial epilepsy groups indicated that there was a significant difference only in attention problems (p = 0.024. Conclusion The present study indicates that the children with epilepsy have more behavioral problems as compared to control group. Therefore, educational and psychological interventions are necessary for supporting desirable psychosocial growth and development of such children.

  12. Effectiveness of 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccine for pneumonia among the elderly - Selection of controls in a case-control study.

    Science.gov (United States)

    Kondo, Kyoko; Suzuki, Kanzo; Washio, Masakazu; Ohfuji, Satoko; Fukushima, Wakaba; Maeda, Akiko; Hirota, Yoshio

    2017-08-24

    We conducted a case-control study to elucidate associations between pneumonia in elderly individuals and 23-valent pneumococcal polysaccharide vaccine (PPSV23) and seasonal influenza vaccine (influenza vaccine). Here, we examined selection of controls in our study using an analytic epidemiology approach. The study period was from October 1, 2009 through September 30, 2014. Cases comprised ≥65-year-old patients newly diagnosed with pneumonia. For every case with pneumonia, two patients with other diseases (one respiratory medicine, one non-respiratory medicine) who were sex-, age-, visit date- and visit hospital-matched were selected as controls. Odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for pneumonia were calculated using conditional logistic regression model. Similar analyses were also conducted based on the clinical department of controls. Analysis was conducted in 234 cases and 438 controls. Effectiveness of pneumococcal vaccination or influenza vaccination against pneumonia was not detected. Proportions of either vaccination in controls were greater among respiratory medicine (pneumococcal vaccine, 38%; influenza vaccine, 55%) than among non-respiratory medicine (23%; 48%). Analysis using controls restricted to respiratory medicine showed marginally significant effectiveness of pneumococcal vaccination (OR, 0.59; 95%CI, 0.34-1.03; P=0.064) and influenza vaccination (0.64; 0.40-1.04; 0.072). However, this effectiveness might have been overestimated by selection bias of controls, as pneumonia cases are not necessarily respiratory medicine patients. In the analysis using controls restricted to non-respiratory medicine, OR of pneumococcal vaccination for pneumonia was close to 1, presumably because the proportion of pneumococcal vaccination was higher in cases than in controls. Because pneumococcal vaccine was not routinely administered during the study period, differences in recommendations of vaccination by physician in different

  13. Organizing pneumonia and occupational and environmental risk factors: a case-control study.

    Science.gov (United States)

    Jobard, Stéphanie; Chaigne, Benjamin; Marchand-Adam, Sylvain; Lasfargues, Gérard; Diot, Elisabeth

    2017-11-01

    A single-center case-control study was carried out to investigate the relationship between occupational and environmental exposure and organizing pneumonia (OP). Thirty-seven cases of OP, including 25 cases of cryptogenic OP, and 111 controls were included. Occupational exposure was assessed retrospectively by an industrial hygienist and an occupational physician, through semi-quantitative estimates of exposure. An exposure score was calculated for each subject, based on probability, intensity, daily frequency, and duration of exposure for each period of employment. The final cumulative exposure score was obtained by summing exposure scores for all periods of employment. Significant associations with all-cause OP were observed for exposure to tetrachloroethylene (OR 13.33, CI 95% 1.44-123.5) and silica (OR 6.61, CI 95% 1.16-37.71). A significant association with cryptogenic OP was observed only for tetrachloroethylene (OR 31.6, CI 95% 1.64-610.8). No associations were found for environmental exposure. Despite its low statistical power, this work suggests that occupational risk factors could be involved in OP.

  14. Challenges in Recruiting Aging Women Holocaust Survivors to a Case Control Study of Breast Cancer.

    Science.gov (United States)

    Vin-Raviv, Neomi; Dekel, Rachel; Barchana, Micha; Linn, Shai; Keinan-Boker, Lital

    2015-01-01

    Older adults are underrepresented in medical research for many reasons, including recruitment difficulties. Recruitment of older adults for research studies is often a time-consuming process and can be more challenging when the study involves older adults with unique exposures to traumatic events and from minority groups. The current article provides a brief overview of (a) challenges encountered while recruiting aging women Holocaust survivors for a case control study and (b) strategies used for meeting those challenges. The case group comprised women Holocaust survivors who were recently diagnosed with breast cancer and the control group comprised healthy women from a Holocaust-survivor community in Israel. Copyright 2015, SLACK Incorporated.

  15. Tuberculosis and diabetes mellitus in the Republic of Kiribati: a case-control study.

    Science.gov (United States)

    Viney, K; Cavanaugh, J; Kienene, T; Harley, D; Kelly, P M; Sleigh, A; O'Connor, J; Mase, S

    2015-05-01

    To better inform local management of TB-diabetes collaborative activities, we aimed to determine the prevalence of diabetes among persons with and without TB and to determine the association between TB and diabetes in Kiribati, a Pacific Island nation. We compared consecutively enrolled TB cases to a group of randomly selected community controls without evidence of TB. Diabetes was diagnosed by HbA1c, and clinical and demographic data were collected. A tuberculin skin test was administered to controls. The chi-square test was used to assess significance in differences between cases and controls. We also calculated an odds ratio, with 95% confidence intervals, for the odds of diabetes among cases relative to controls. Unweighted multivariate logistic regression was performed to adjust for the effects of age and sex. A total of 275 TB cases and 499 controls were enrolled. The diabetes prevalence in cases (101, 37%) was significantly greater than in controls (94, 19%) (adjusted odds ratio: 2.8; 95% CI 2.0-4.1). Fifty-five percent (108) of all diabetic diagnoses were new; this proportion was higher among controls (64.8%) than cases (46.5%). Five patients with TB were screened to detect one patient with diabetes. There is a strong association between TB and diabetes in Kiribati and bidirectional screening should be conducted in this setting. © 2015 John Wiley & Sons Ltd.

  16. The diagnostic role of cervico-vaginal fluid interleukins-1α in endometriosis: A case-control study

    OpenAIRE

    Farahnaz Mardanian; Zahra Sheikh-Soleimani

    2014-01-01

    Background: Endometriosis is a chronic and progressive gynecological disorder and is manifest by dysmenorrhea and a major cause of infertility and chronic pelvic pain. The study was designed to compare the value of cervico-vaginal fluid of interleukin-1? (IL-1?) in patients with and without endometriosis. Materials and Methods: Fifty women were assessed in this case control study. The case group included 25 patients with endometriosis. The control group included 25 women without any evidence ...

  17. An intronic single-nucleotide polymorphism (rs13217795) in FOXO3 is associated with asthma and allergic rhinitis: a case-case-control study.

    Science.gov (United States)

    Amarin, Justin Z; Naffa, Randa G; Suradi, Haya H; Alsaket, Yousof M; Obeidat, Nathir M; Mahafza, Tareq M; Zihlif, Malek A

    2017-11-15

    Asthma and allergic rhinitis are respiratory diseases with a significant global burden. Forkhead box O3 (FOXO3) is a gene involved in the etiology of a number of respiratory diseases. The objective of this study is to assess the association of rs13217795, an intronic FOXO3 single-nucleotide polymorphism, with asthma and allergic rhinitis. In this case-case-control genetic association study, genotyping was conducted using the PCR-RFLP method. Genotype-based associations were investigated under the general, recessive, and dominant models of disease penetrance using binomial logistic regression; and, allele-based associations were tested using Pearson's chi-squared test. The final study population consisted of 94 controls, 124 asthmatics, and 110 allergic rhinitis patients. The general and recessive models of disease penetrance were statistically significant for both case-control comparisons. Under the general model, the odds of the asthma phenotype were 1.46 (0.64 to 3.34) and 3.42 (1.37 to 8.57) times higher in heterozygotes and derived allele homozygotes, respectively, compared to ancestral allele homozygotes. The corresponding odds ratios for the allergic rhinitis phenotype were 1.05 (0.46 to 2.40) and 2.35 (0.96 to 5.73), respectively. The dominant model of disease penetrance was not statistically significant. The minor allele in all study groups was the ancestral allele, with a frequency of 0.49 in controls. There was no deviation from Hardy-Weinberg equilibrium in controls. Both case-control allele-based associations were statistically significant. Herein we present the first report of the association between rs13217795 and allergic rhinitis, and the first independent verification of the association between rs13217795 and asthma. Marker selection in future genetic association studies of asthma and allergic rhinitis should include functional polymorphisms in linkage disequilibrium with rs13217795.

  18. Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

    Directory of Open Access Journals (Sweden)

    Ruth H. Keogh

    2016-01-01

    Full Text Available Abstract Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

  19. Population-based case-control study of childhood leukemia in Shanghai

    International Nuclear Information System (INIS)

    Shu, X.O.; Gao, Y.T.; Brinton, L.A.; Linet, M.S.; Tu, J.T.; Zheng, W.; Fraumeni, J.F. Jr.

    1988-01-01

    A population-based case-control interview study of 309 childhood leukemia cases and 618 healthy population control children was conducted in urban Shanghai, China. Like some studies in other countries, excess risks for both acute lymphocytic leukemia (ALL) and acute nonlymphocytic leukemia (ANLL) were associated with intrauterine and paternal preconception diagnostic x-ray exposure, and with maternal employment in the chemical and agricultural industries during pregnancy. ANLL was linked to maternal occupational exposure to benzene during pregnancy, whereas both ALL and ANLL were significantly associated with maternal exposure to gasoline and the patient's prior use of chloramphenicol. New findings, previously unsuspected, included an association of ANLL with younger maternal age at menarche (odds ratio [OR] = 4.3; 95% confidence interval (CI) = 1.3-13.9); a protective effect for long-term (greater than 1 year) use of cod liver oil containing vitamins A and D for both ALL (OR = 0.4; 95% CI = 0.2-0.9) and ANLL (OR = 0.3; 95% CI = 0.1-1.0); and excess risks of ANLL among children whose mothers were employed in metal refining and processing (OR = 4.6; 95% CI = 1.3-17.2) and of ALL associated with maternal occupational exposure to pesticides (OR = 3.5; 95% CI = 1.1-11.2). No relationships were found with late maternal age, certain congenital disorders, or familial occurrence, which have been related to childhood leukemia in other studies. In contrast with other reports, an excess of leukemia, primarily ANLL, occurred among second or later-born rather than firstborn children

  20. Level of neurotoxic metals in amyotrophic lateral sclerosis: A population-based case-control study.

    Science.gov (United States)

    Bocca, Beatrice; Forte, Giovanni; Oggiano, Riccardo; Clemente, Simonetta; Asara, Yolande; Peruzzu, Angela; Farace, Cristiano; Pala, Salvatore; Fois, Alessandro Giuseppe; Pirina, Pietro; Madeddu, Roberto

    2015-12-15

    The association between exposure to toxic metals and amyotrophic lateral sclerosis (ALS) was explored in a population-based case-control study in the Sardinia island (Italy), a region characterized by elevated rates of ALS cases. In 34 patients with ALS (mean age, 62 ± 10 years) and 30 controls (mean age, 65 ± 11 years), Al, Cd, Hg, Mn and Pb were determined in blood, hair and urine by sector field inductively coupled mass spectrometry. Results indicated that, in blood, concentrations of Al (p=0.045) and Pb were higher (p=0.026) in ALS patients than in control subjects. In hair, a depletion of Al (p=0.006) and Mn (p=0.032) concentrations in ALS subjects respect to controls was found. In urine, no significant differences between cases and controls were observed. Thus, some metals seemed to be associated with ALS degeneration, but a definitive conclusion is still far considering the multiple risk factors (genetic mutations, environmental toxicants and stressors) involved in the disease. Finally, the interpretation that deregulated metal concentrations can be a consequence of the degenerative process, rather than a cause, is also valid. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. The Impact of Trachomatous Trichiasis on Quality of Life: A Case Control Study.

    Directory of Open Access Journals (Sweden)

    Esmael Habtamu

    2015-11-01

    Full Text Available Trachomatous trichiasis is thought to have a profound effect on quality of life (QoL, however, there is little research in this area. We measured vision and health-related QoL in a case-control study in Amhara Region, Ethiopia.We recruited 1000 adult trichiasis cases and 200 trichiasis-free controls, matched to every fifth trichiasis case on age (+/- two years, sex and location. Vision-related quality of life (VRQoL and health-related quality of life (HRQoL were measured using the WHO/PBD-VF20 and WHOQOL-BREF questionnaires. Comparisons were made using linear regression adjusted for age, sex and socioeconomic status. Trichiasis cases had substantially lower VRQoL than controls on all subscales (overall eyesight, visual symptom, general functioning and psychosocial, p<0.0001, even in the sub-group with normal vision (p<0.0001. Lower VRQoL scores in cases were associated with longer trichiasis duration, central corneal opacity, visual impairment and poor contrast sensitivity. Trichiasis cases had lower HRQoL in all domains (Physical-health, Psychological, Social, Environment, p<0.0001, lower overall QoL (mean, 34.5 v 64.6; p<0.0001 and overall health satisfaction (mean, 38.2 v 71.7; p<0.0001. This association persisted in a sub-group analysis of cases and controls with normal vision. Not having a marriage partner (p<0.0001, visual impairment (p = 0.0068, daily labouring (p<0.0001, presence of other health problems (p = 0.0018 and low self-rated wealth (p<0.0001 were independently associated with lower overall QoL scores in cases. Among cases, trichiasis caused 596 (59% to feel embarrassed, 913 (91.3% to worry they may lose their remaining eyesight and 681 (68.1% to have sleep disturbance.Trachomatous trichiasis substantially reduces vision and health related QoL and is disabling, even without visual impairment. Prompt trichiasis intervention is needed both to prevent vision loss and to alleviate physical and psychological suffering, social

  2. Quantifying the impact of selection bias caused by nonparticipation in a case-control study of mobile phone use

    DEFF Research Database (Denmark)

    Vrijheid, Martine; Richardson, Lesley; Armstrong, Bruce K

    2009-01-01

    To quantitatively assess the impact of selection bias caused by nonparticipation in a multinational case-control study of mobile phone use and brain tumor.......To quantitatively assess the impact of selection bias caused by nonparticipation in a multinational case-control study of mobile phone use and brain tumor....

  3. Haplotype-based case-control study between human apurinic/apyrimidinic endonuclease 1/redox effector factor-1 gene and cerebral infarction.

    Science.gov (United States)

    Naganuma, Takahiro; Nakayama, Tomohiro; Sato, Naoyuki; Fu, Zhenyan; Yamaguchi, Mai; Soma, Masayoshi; Aoi, Noriko; Usami, Ron; Doba, Nobutaka; Hinohara, Shigeaki

    2009-10-01

    The aim of this study was to investigate the relationship between cerebral infarction (CI) and the human apurinic/apyrimidinic endonuclease 1/redox effector factor-1 (APE1/REF-1) gene using single-nucleotide polymorphisms (SNPs) and a haplotype-based case-control study. We selected 5 SNPs in the human APE1/REF1 gene (rs1760944, rs3136814, rs17111967, rs3136817 and rs1130409), and performed case-control studies in 177 CI patients and 309 control subjects. rs17111967 was found to have no heterogeneity in Japanese. The overall distribution of the haplotype-based case-control study constructed by rs1760944, rs3136814 and rs1130409 showed a significant difference. The frequency of the G-C-T haplotype was significantly higher in the CI group than in the control group (2.5% vs. 0.0%, p>0.001). Based on the results of the haplotype-based case-control-study, the G-C-T haplotype may be a genetic marker of CI, and the APE1/REF-1 gene may be a CI susceptibility gene.

  4. Postnatal risk factors for testicular cancer: The EPSAM case-control study.

    Science.gov (United States)

    Moirano, Giovenale; Zugna, Daniela; Grasso, Chiara; Mirabelli, Dario; Lista, Patrizia; Ciuffreda, Libero; Segnan, Nereo; Merletti, Franco; Richiardi, Lorenzo

    2017-11-01

    Testicular cancer is considered to originate from an impaired differentiation of fetal germ cells, but puberty could represent another time window of susceptibility. Our study aimed at investigating the association between environmental exposures acting during puberty/adolescence (13-19 years of age) and the risk of testicular cancer. We used data of the EPSAM study, a case-control study on germ-cell testicular cancer conducted in the province of Turin, Italy, involving cases diagnosed between 1997 and 2008. Histologically confirmed cases (n = 255) and controls (n = 459) completed a postal questionnaire focusing in particular on the pubertal period (namely age 13 years) with questions on physical activity (competitive sports, gardening), lifestyle (alcohol consumption, smoking), occupational history and medical conditions. All analyses were adjusted for the matching variables, cryptorchidism and educational level. Having done at least one competitive sport during puberty (odds ratio [OR]: 0.72, 95% confidence interval: 0.52-1.00), gardening activities during puberty (OR: 0.62, 0.42-0.94) and having a lower weight than peers during puberty (OR: 0.64, 0.42-0.97) were all inversely associated with the risk of testicular cancer. No evidence of association between smoking or alcohol consumption during puberty and the risk of testicular cancer was observed. Regarding agriculture-related occupations, we found an association with the risk of testicular cancer both for occasional jobs during puberty (OR: 2.40, 95% CI: 1.08-5.29) and ever employment in adolescence (OR: 2.59, 95% CI: 0.83-8.10). Our results suggest that postnatal exposures could play a role in testicular cancer aetiology, at least when acting in puberty or adolescence. © 2017 UICC.

  5. A Case Study on Cyber-security Program for the Programmable Logic Controller of Modern NPPs

    International Nuclear Information System (INIS)

    Song, S. H.; Lee, M. S.; Kim, T. H.; Park, C. H.; Park, S. P.; Kim, H. S.

    2014-01-01

    As instrumentation and control (I and C) systems for modern Nuclear Power Plants (NPPs) have been digitalized to cope with their growing complexity, the cyber-security has become an important issue. To protect the I and C systems adequately from cyber threats, such as Stuxnet that attacked Iran's nuclear facilities, regulations of many countries require a cyber-security program covering all the life cycle phases of the system development, from the concept to the retirement. This paper presents a case study of cyber-security program that has been performed during the development of the programmable logic controller (PLC) for modern NPPs of Korea. In the case study, a cyber-security plan, including technical, management, and operational controls, was established through a security risk assessment. Cyber-security activities, such as development of security functions and periodic inspections, were conducted according to the plan: the security functions were applied to the PLC as the technical controls, and periodic inspections and audits were held to check the security of the development environment, as the management and operational controls. A final penetration test was conducted to inspect all the security problems that had been issued during the development. The case study has shown that the systematic cyber-security program detected and removed the vulnerabilities of the target system, which could not be found otherwise, enhancing the cyber-security of the system

  6. A Case Study on Cyber-security Program for the Programmable Logic Controller of Modern NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Song, S. H. [Korea University, Seoul (Korea, Republic of); Lee, M. S.; Kim, T. H. [Formal Work Inc., Seoul (Korea, Republic of); Park, C. H. [LINE Corp., Tokyo (Japan); Park, S. P. [Ahnlab Inc., Seoul (Korea, Republic of); Kim, H. S. [Sejong University, Seoul (Korea, Republic of)

    2014-08-15

    As instrumentation and control (I and C) systems for modern Nuclear Power Plants (NPPs) have been digitalized to cope with their growing complexity, the cyber-security has become an important issue. To protect the I and C systems adequately from cyber threats, such as Stuxnet that attacked Iran's nuclear facilities, regulations of many countries require a cyber-security program covering all the life cycle phases of the system development, from the concept to the retirement. This paper presents a case study of cyber-security program that has been performed during the development of the programmable logic controller (PLC) for modern NPPs of Korea. In the case study, a cyber-security plan, including technical, management, and operational controls, was established through a security risk assessment. Cyber-security activities, such as development of security functions and periodic inspections, were conducted according to the plan: the security functions were applied to the PLC as the technical controls, and periodic inspections and audits were held to check the security of the development environment, as the management and operational controls. A final penetration test was conducted to inspect all the security problems that had been issued during the development. The case study has shown that the systematic cyber-security program detected and removed the vulnerabilities of the target system, which could not be found otherwise, enhancing the cyber-security of the system.

  7. The Relationship between Chronic Constipation and Urinary Tract Infection in Children: A Case-Control Clinical Study

    Directory of Open Access Journals (Sweden)

    Gholamreza Sarvari

    2017-09-01

    Full Text Available Background Urinary tract infection (UTI is one of the most common bacterial infections in children, if not diagnosed leads to serious complications such as hypertension, chronic renal failure and renal scar. Constipation is one of the main risk factors for recurrent UTI. The aim of present study was to investigate the relationship between chronic constipation and urinary tract infection in children. Materials and Methods In this case-control study 105 patients with functional chronic constipation as case group, compared with 104 children without chronic constipation as control. The control group was matched according to gender and age. The prevalence of UTI in children with and without constipation as well as their improvement was compared after treatment. Results The prevalence of UTI in case and control groups was 13.3% and 6.7%, respectively (P=0.17. The prevalence of UTI in case group decreased to 3.8% after treatment of constipation. Escherichia coli (E coli was the most commonly isolated organism in both groups. Conclusion Results of present study showed that despite of no significant urinary tract infection incidence between children with constipation and those without constipation, the constipation should still be considered as a predisposing risk factor for the UTI occurrence.

  8. Social outcomes of young adults with childhood-onset epilepsy: A case-sibling-control study.

    Science.gov (United States)

    Baca, Christine B; Barry, Frances; Vickrey, Barbara G; Caplan, Rochelle; Berg, Anne T

    2017-05-01

    We aimed to compare long-term social outcomes in young adults with childhood-onset epilepsy (cases) with neurologically normal sibling controls. Long-term social outcomes were assessed at the 15-year follow-up of the Connecticut Study of Epilepsy, a community-based prospective cohort study of children with newly diagnosed epilepsy. Young adults with childhood-onset epilepsy with complicated (abnormal neurologic exam findings, abnormal brain imaging with lesion referable to epilepsy, intellectual disability (ID; IQ < 60) or informative history of neurologic insults to which the occurrence of epilepsy might be attributed), and uncomplicated epilepsy presentations were compared to healthy sibling controls. Age, gender, and matched-pair adjusted generalized linear models stratified by complicated epilepsy and 5-year seizure-free status estimated adjusted odds ratios (aORs) and 95% confidence intervals [CIs] for each outcome. The 15-year follow-up included 361 individuals with epilepsy (59% of initial cases; N = 291 uncomplicated and N = 70 complicated epilepsy; mean age 22 years [standard deviation, SD 3.5]; mean epilepsy onset 6.2 years [SD 3.9]) and 173 controls. Social outcomes for cases with uncomplicated epilepsy with ≥5 years terminal remission were comparable to controls; cases with uncomplicated epilepsy <5 years seizure-free were more likely to be less productive (school/employment < 20 h/week) (aOR 3.63, 95% CI 1.83-7.20) and not to have a driver's license (aOR 6.25, 95% CI 2.85-13.72). Complicated cases with epilepsy <5 years seizure-free had worse outcomes across multiple domains; including not graduating high school (aOR 24.97, 95% CI 7.49-83.30), being un- or underemployed (<20 h/week) (aOR 11.06, 95% CI 4.44-27.57), being less productively engaged (aOR 15.71, 95% CI 6.88-35.88), and not living independently (aOR 10.24, 95% CI 3.98-26.36). Complicated cases without ID (N = 36) had worse outcomes with respect to productive engagement (aOR 6.02; 95% CI 2

  9. HPV and cofactors for invasive cervical cancer in Morocco: a multicentre case-control study.

    Science.gov (United States)

    Berraho, Mohamed; Amarti-Riffi, Afaf; El-Mzibri, Mohammed; Bezad, Rachid; Benjaafar, Noureddine; Benideer, Abdelatif; Matar, Noureddine; Qmichou, Zinab; Abda, Naima; Attaleb, Mohammed; Znati, Kaoutar; El Fatemi, Hind; Bendahhou, Karima; Obtel, Majdouline; Filali Adib, Abdelhai; Mathoulin-Pelissier, Simone; Nejjari, Chakib

    2017-06-20

    Limited national information is available in Morocco on the prevalence and distribution of HPV-sub-types of cervical cancer and the role of other risk factors. The aim was to determine the frequency of HPV-sub-types of cervical cancer in Morocco and investigate risk factors for this disease. Between November 2009 and April 2012 a multicentre case-control study was carried out. A total of 144 cases of cervical cancer and 288 age-matched controls were included. Odds-ratios and corresponding confidence-intervals were computed by conditional logistic regression models. Current HPV infection was detected in 92.5% of cases and 13.9% of controls. HPV16 was the most common type for both cases and controls. Very strong associations between HPV-sub-types and cervical cancer were observed: total-HPV (OR = 39), HPV16 (OR = 49), HPV18 (OR = 31), and multiple infections (OR = 13). Education, high parity, sexual intercourse during menstruation, history of sexually transmitted infections, and husband's multiple sexual partners were also significantly associated with cervical cancer in the multivariate analysis. Our results could be used to establish a primary prevention program and to prioritize limited screening to women who have specific characteristics that may put them at an increased risk of cervical cancer.

  10. Mild asthma and chronic bronchitis seem to influence functional exercise capacity: a multi-case control study.

    Science.gov (United States)

    Marcon, Alessandro; Girardi, Paolo; Ferrari, Marcello; Olivieri, Mario; Accordini, Simone; Bombieri, Cristina; Bortolami, Oscar; Braggion, Marco; Cappa, Veronica; Cazzoletti, Lucia; Locatelli, Francesca; Nicolis, Morena; Perbellini, Luigi; Sembeni, Silvia; Verlato, Giuseppe; Zanolin, Maria Elisabetta; de Marco, Roberto

    2013-01-01

    In the Genes Environment Interaction in Respiratory Diseases population-based multi-case control study, we investigated whether asthma, chronic bronchitis (CB) and rhinitis were associated with a reduced 6-minute walk distance (6MWD), and whether the 6MWD determinants were similar for subjects with/without respiratory diseases. Cases of asthma (n = 360), CB (n = 120), rhinitis (n = 203) and controls (no respiratory diseases: n = 302) were recruited. The variation in the 6MWD across the groups was analyzed by ANCOVA, adjusting for gender, age, height, weight and comorbidity. The 6MWD determinants were studied by linear regression, and heterogeneity across the cases and controls was investigated. The 6MWD differed across cases and controls (p = 0.01). It was shorter for cases of asthma (-17.1, 95% CI -28.3 to -5.8 m) and CB (-20.7, 95% CI: -36.6 to -4.8 m) than for controls (604 ± 68 m on average), but not for cases of rhinitis. The negative association between age and the 6MWD was significant for cases of CB, but not for the other groups (p = 0.001). Even at the level of severity found in the general population, asthma and CB could influence the 6MWD, which seems to reflect the functional exercise level for daily physical activities. The negative association between ageing and the 6MWD was particularly strong in subjects with CB. Our report adds to the mounting evidence that CB is not a trivial condition, especially in the ageing adult population, and it supports the importance of monitoring functional capacity and of physical reconditioning in mild asthma. Copyright © 2013 S. Karger AG, Basel.

  11. A population-based case-control study of the safety of oral anti-tuberculosis drug treatment during pregnancy

    DEFF Research Database (Denmark)

    Czeizel, A.E.; Rockenbauer, M.; Olsen, J.

    2001-01-01

    OUTCOME MEASURES: Congenital abnormalities in newborn infants and fetuses diagnosed prenatally during the second and third trimesters, and postnatally from birth to the age of one year. RESULTS: Of 38,151 controls, 29 (0.08%) were exposed to anti-tuberculosis drug treatment during pregnancy......OBJECTIVE: To study the human teratogenic potential of isoniazid and other anti-tuberculosis drug treatment during pregnancy. DESIGN AND SETTING: Cases from a large population-based dataset at the Hungarian Case-Control Surveillance of Congenital Abnormalities, and controls from the National Birth...... Registry, between 1980 and 1996. Information on all oral anti-tuberculosis drug treatments during pregnancy was medically recorded. STUDY PARTICIPANTS: Women who had newborns or fetuses with congenital abnormalities (case group), and women who had babies with no congenital abnormality (control group). MAIN...

  12. The art and science of flow control - case studies using flow visualization methods

    Science.gov (United States)

    Alvi, F. S.; Cattafesta, L. N., III

    2010-04-01

    Active flow control (AFC) has been the focus of significant research in the last decade. This is mainly due to the potentially substantial benefits it affords. AFC applications range from the subsonic to the supersonic (and beyond) regime for both internal and external flows. These applications are wide and varied, such as controlling flow transition and separation over various external components of the aircraft to active management of separation and flow distortion in engine components and over turbine and compressor blades. High-speed AFC applications include control of flow oscillations in cavity flows, supersonic jet screech, impinging jets, and jet-noise control. In this paper we review some of our recent applications of AFC through a number of case studies that illustrate the typical benefits as well as limitations of present AFC methods. The case studies include subsonic and supersonic canonical flowfields such as separation control over airfoils, control of supersonic cavity flows and impinging jets. In addition, properties of zero-net mass-flux (ZNMF) actuators are also discussed as they represent one of the most widely studied actuators used for AFC. In keeping with the theme of this special issue, the flowfield properties and their response to actuation are examined through the use of various qualitative and quantitative flow visualization methods, such as smoke, shadowgraph, schlieren, planar-laser scattering, and Particle image velocimetry (PIV). The results presented here clearly illustrate the merits of using flow visualization to gain significant insight into the flow and its response to AFC.

  13. Delirium markers in older fallers: a case-control study

    Directory of Open Access Journals (Sweden)

    Doherty K

    2014-11-01

    Full Text Available Kelly Doherty,1 Elizabeth Archambault,1 Brittany Kelly,1,2 James L Rudolph1,3,4 1Geriatric Research, Education, and Clinical Center, VA Boston Healthcare System, Boston, MA, USA; 2School of Nursing, Science & Health Professions, Regis College, Boston, MA, USA; 3Division of Aging, Brigham and Women’s Hospital, Boston, MA, USA; 4Harvard Medical School, Boston, MA, USA Background: When a hospitalized older patient falls or develops delirium, there are significant consequences for the patient and the health care system. Assessments of inattention and altered consciousness, markers for delirium, were analyzed to determine if they were also associated with falls. Methods: This retrospective case-control study from a regional tertiary Veterans Affairs referral center identified falls and delirium risk factors from quality databases from 2010 to 2012. Older fallers with complete delirium risk assessments prior to falling were identified. As a control, non-fallers were matched at a 3:1 ratio. Admission risk factors that were compared in fallers and non-fallers included altered consciousness, cognitive performance, attention, sensory deficits, and dehydration. Odds ratio (OR was reported (95% confidence interval [CI]. Results: After identifying 67 fallers, the control population (n=201 was matched on age (74.4±9.8 years and ward (83.6% medical; 16.4% intensive care unit. Inattention as assessed by the Months of the Year Backward test was more common in fallers (67.2% versus 50.8%, OR=2.0; 95% CI: 1.1–3.7. Fallers tended to have altered consciousness prior to falling (28.4% versus 12.4%, OR=2.8; 95% CI: 1.3–5.8. Conclusion: In this case-control study, alterations in consciousness and inattention, assessed prior to falling, were more common in patients who fell. Brief assessments of consciousness and attention should be considered for inclusion in fall prediction. Keywords: geriatrics, patient centered outcomes research, patient safety

  14. Design of a PLC control program for a batch plant : VHS case study 1

    NARCIS (Netherlands)

    Mader, A.H.; Brinksma, E.; Wupper, H.; Bauer, N.

    2001-01-01

    This article reports on the systematic design and validation of a PLC control program for the batch plant that has been selected as a case study for the EC project on Verification of Hybrid Systems (VHS). We show how a correct design of the control program can be obtained in an incremental manner

  15. Design of a PLC Control Program for a Batch Plant - VHS Case Study 1

    NARCIS (Netherlands)

    Mader, Angelika H.; Brinksma, Hendrik; Wupper, H.; Bauer, N.

    2001-01-01

    This article reports on the systematic design and validation of a PLC control program for the batch plant that has been selected as a case study for the EC project on Verification of Hybrid Systems (VHS). We show how a correct design of the control program can be obtained in an incremental manner

  16. High Prevalence of Human Papillomavirus in Colorectal Cancer in Hispanics: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Raul D. Bernabe-Dones

    2016-01-01

    Full Text Available The role of Human Papillomavirus (HPV in colorectal carcinogenesis remains elusive. Based on the high incidence of HPV-associated malignancies among Puerto Rican Hispanics, this study aimed to assess the prevalence of HPV infection and viral integration in colorectal tissues in order to evaluate its putative role in colorectal cancer (CRC. In this case-control study, the prevalence of HPV infection in CRC (cases n = 45 and normal colon mucosa from cancer-free subjects (controls n = 36 was assessed by a nested PCR strategy. HPV-16 genotyping was performed in HPV-positive tissues and the physical status of the HPV-16 genome was determined by E2 detection. HPV was detected in 19 of 45 (42.2% CRC cases (mean age 61.1 ± 10.7 years, 24 males and in 1 of 36 (2.8% controls (mean age 60.9 ± 9.6 years, 24 males with an OR = 25.58 (95% CI 3.21 to 203.49. HPV-16 was detected in 63.2% of the HPV-positive colorectal tumors; genome integration was observed in all HPV-16 positive cases. This is the first report showing the high prevalence of HPV infections in Caribbean Hispanic colorectal tumors. Despite evidence of HPV integration into the host genome, further mechanistic analysis examining HPV oncoprotein expression and the putative role of these oncoproteins in colorectal carcinogenesis is warranted.

  17. Advantages of the nested case-control design in diagnostic research

    Directory of Open Access Journals (Sweden)

    Hoes Arno W

    2008-07-01

    Full Text Available Abstract Background Despite its benefits, it is uncommon to apply the nested case-control design in diagnostic research. We aim to show advantages of this design for diagnostic accuracy studies. Methods We used data from a full cross-sectional diagnostic study comprising a cohort of 1295 consecutive patients who were selected on their suspicion of having deep vein thrombosis (DVT. We draw nested case-control samples from the full study population with case:control ratios of 1:1, 1:2, 1:3 and 1:4 (per ratio 100 samples were taken. We calculated diagnostic accuracy estimates for two tests that are used to detect DVT in clinical practice. Results Estimates of diagnostic accuracy in the nested case-control samples were very similar to those in the full study population. For example, for each case:control ratio, the positive predictive value of the D-dimer test was 0.30 in the full study population and 0.30 in the nested case-control samples (median of the 100 samples. As expected, variability of the estimates decreased with increasing sample size. Conclusion Our findings support the view that the nested case-control study is a valid and efficient design for diagnostic studies and should also be (reappraised in current guidelines on diagnostic accuracy research.

  18. A population-based case-control study on statin exposure and risk of acute diverticular disease.

    Science.gov (United States)

    Sköldberg, Filip; Svensson, Tobias; Olén, Ola; Hjern, Fredrik; Schmidt, Peter T; Ljung, Rickard

    2016-01-01

    A reduced risk of perforated diverticular disease among individuals with current statin exposure has been reported. The aim of the present study was to investigate whether statins reduce the risk of acute diverticular disease. A nation-wide population-based case-control study was performed, including 13,127 cases hospitalised during 2006-2010 with a first-time diagnosis of colonic diverticular disease, and 128,442 control subjects (matched for sex, age, county of residence and calendar year). Emergency surgery, assumed to be a proxy for complicated diverticulitis, was performed on 906 of the cases during the index admission, with 8818 matched controls. Statin exposure was classified as "current" or "former" if a statin prescription was last dispensed ≤ 125 days or >125 days before index date, respectively. The association between statin exposure and acute diverticular disease was investigated by conditional logistic regression, including models adjusting for country of birth, educational level, marital status, comorbidities, nonsteroidal anti-inflammatory drug/steroid exposure and healthcare utilisation. A total of 1959 cases (14.9%) and 16,456 controls (12.8%) were current statin users (crude OR 1.23 [95% CI 1.17-1.30]; fully adjusted OR 1.00 [0.94-1.06]). One hundred and thirty-two of the cases subjected to surgery (14.6%), and 1441 of the corresponding controls (16.3%) were current statin users (crude OR 0.89 [95% CI 0.73-1.08]; fully adjusted OR 0.70 [0.55-0.89]). The results do not indicate that statins affect the development of symptomatic diverticular disease in general. However, current statin use was associated with a reduced risk of emergency surgery for diverticular disease.

  19. The Association Between Urban Tree Cover and Gun Assault: A Case-Control and Case-Crossover Study.

    Science.gov (United States)

    Kondo, Michelle C; South, Eugenia C; Branas, Charles C; Richmond, Therese S; Wiebe, Douglas J

    2017-08-01

    Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems-assisted interviews with boys and men aged 10-24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot with a firearm and 274 community controls, during 2008-2011. Each subject reported a step-by-step mapped account of where and with whom they traveled over a full day from waking until being assaulted or going to bed. Geocoded path points were overlaid on mapped layers representing tree locations and place-specific characteristics. Conditional logistic regressions were used to compare case subjects versus controls (case-control) and case subjects at the time of injury versus times earlier that day (case-crossover). When comparing cases at the time of assault to controls matched at the same time of day, being under tree cover was inversely associated with gunshot assault (odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.55, 0.88), especially in low-income areas (OR = 0.69, 95% CI: 0.54, 0.87). Case-crossover models confirmed this inverse association overall (OR = 0.55, 95% CI: 0.34, 0.89) and in low-income areas (OR = 0.54, 95% CI: 0.33, 0.88). Urban greening and tree cover may hold promise as proactive strategies to decrease urban violence. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  20. Hematological Indices in Children with Non-organic Failure to Thrive: a Case-Control Study.

    Science.gov (United States)

    Jafari Nodoshan, A H; Hashemi, A; Golzar, A; Karami, F; Akhondzaraini, R

    2016-01-01

    Non-organic failure to thrive (NFTT) is the most common cause of failure to thrive (FTT) which is attributed to inadequate nutrition due to economic factors or parental neglect . NFTT can lead to a vicious cycle of poor and inadequate eating and severity of anemia. The aim of this study was to determine the hematological indices in children with NFTT. In a cross sectional case control study, iron status and blood indices of forty five aged 6-60 months children with NFTT were evaluated and compared with 45 healthy control children (with matching of age and sex). In this study, the prevalence of anemia was 48.9% in NFTT compared to 11.4% in the control group (p<0.001). Microcytic anemia was significantly more prevalent among the subjects than the controls (77.8% versus 27.3%; p<0. 001). The serum iron level was 73.2 and 62.8 mcg/dl for the case and control groups (P=0.29). The ferritin level in the study group was 29.8 versus 35.47 ng/ml in the control group (p=0.227). The prevalence of iron deficiency anemia among children with mild, moderate, and severe underweight was 44.4%, 45.5%, and 48%, respectively. The highest prevalence of iron-deficiency anemia was seen between age group of 12 and 24 months (p<0.05). Based on the results of this study, a correlation between malnutrition and anemia was found. However, further studies are needed to assess and confirm the current outcomes.

  1. ABO blood group and esophageal carcinoma risk: from a case-control study in Chinese population to meta-analysis.

    Science.gov (United States)

    Wang, Wei; Liu, Lei; Wang, Zhiwei; Lu, Xiaopeng; Wei, Min; Lin, Tianlong; Zhang, Yixin; Jiang, Songqi; Wang, Qiang; Cao, Ziang; Shi, Minxin

    2014-10-01

    The association between ABO blood group and the risk of esophageal carcinoma (EC) in previously published studies is uncertain and conflicting. The aim of the current study was to determine the correlation of ABO blood group with EC risk via a case-control study and meta-analysis. We performed a population-based case-control study of 3,595 cases and 41,788 controls in Chinese population to evaluate the association between ABO blood group and EC risk. Then, a comprehensive meta-analysis combining our original data and previously published data was conducted to clearly discern the real relationship. The strength of association was measured by odds ratios (ORs) with 95% confidence intervals (CI). In our case-control study, the risk of EC in blood group B was significantly higher than that in non-B groups (A, O, and AB) (OR = 1.15, 95% CI 1.09-1.21). Compared with non-O groups (A, B, and AB), individuals with blood group O demonstrated a reduced risk of EC (OR = 0.90, 95% CI 0.85-0.94). The meta-analysis also indicated that blood group B was associated with significantly higher EC risk (OR = 1.20, 95% CI 1.10-1.31), and people with blood group O had a decreased EC risk (OR = 0.94, 95% CI 0.90-0.99). Neither the case-control study nor the meta-analysis produced any significant association of blood group A or AB with EC risk. Results from our case-control study and the followed meta-analysis confirmed that there was an increased risk of EC in blood group B individuals, whereas a decreased risk of EC was observed in blood group O individuals.

  2. Risk factors for near-fatal asthma. A case-control study in hospitalized patients with asthma.

    Science.gov (United States)

    Turner, M O; Noertjojo, K; Vedal, S; Bai, T; Crump, S; Fitzgerald, J M

    1998-06-01

    We prospectively recruited patients admitted to the hospital with severe asthma to comprehensively evaluate the association of historical and physiologic features with the risk of near-fatal asthma (NFA). A case-control study design was used. All patients admitted with NFA (cases) were identified prospectively and compared with asthma patients admitted during the same period without respiratory failure (controls). Nineteen cases (age: 40.2 +/- 12.0 yr) (mean +/- SD) and 80 controls (age: 36 +/- 13.5 yr) were enrolled. Duration of asthma, gender, smoking status, ethnicity, and prevalence of atopy were similar in the case and control groups. More than 80% of patients in both groups reported worsening symptoms for more than 48 h before admission, and more than 50% were worse for longer than 7 d. There was no difference in degree of airways obstruction or bronchial hyperresponsiveness (PC20). Perception of dyspnea was similar in the cases and controls, but among cases the males had greater impairment than the females (Borg score: 1.9 +/- 1. 4 versus 3.9 +/- 1.2: p = 0.05). Univariate analysis identified a history of previous mechanical ventilation (OR: 27.5; 95% CI: 6.60 to 113.7), admission to the intensive care unit (ICU) (OR: 9.9; 95% CI: 3.0 to 32.9), history of worse asthma during January and February (OR: 3.5; 95% CI: 1.0 to 11.8), and use of air-conditioning (OR: 15.0; 95% CI: 1.3 to 166) as risk factors for NFA. Of concern was the dependence of most patients (59.8%) on the emergency department (ED) for initial care, and the small number of cases (16%) in which patients visited a physician before admission to the hospital. We have confirmed risk factors identified previously in retrospective studies of fatal and NFA, and have also shown that hospitalized patients with asthma, irrespective of severity of their asthma, share several characteristics, especially in terms of their failure to respond to worsening asthma.

  3. Thimerosal exposure and increased risk for diagnosed tic disorder in the United States: a case-control study

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    Geier David A.

    2015-06-01

    Full Text Available A hypothesis testing, case-control study evaluated automated medical records for exposure to organic-Hg from Thimerosal-containing hepatitis B vaccines (TM-HepB administered at specific intervals in the first six-months-of-life among cases diagnosed with a tic disorder (TD or cerebral degeneration (CD (an outcome not biologically plausibly linked to TM exposure in comparison to controls; both cases and controls were continuously enrolled from birth (born from 1991–2000 within the Vaccine Safety Datalink (VSD database. TD cases were significantly more likely than controls to have received increased organic-Hg from TM-HepB administered within the first month-of-life (odds ratio (OR=1.59, p<0.00001, first two-months-of-life (OR=1.59, p<0.00001, and first six-months-of-life (OR=2.97, p<0.00001. Male TD cases were significantly more likely than male controls to have received increased organic-Hg from TM-HepB administered within the first month-of-life (OR =1.65, p<0.0001, first two-months-of-life (OR=1.64, p<0.0001, and first six months-of-life (OR=2.47, p<0.05, where as female TD were significantly more likely than female controls to have received increased organic-Hg from TM-HepB administered within the first six-months-of-life (OR=4.97, p<0.05. By contrast, CD cases were no more likely than controls to have received increased organic-Hg exposure from TM-HepB administered at any period studied within the first six-months-of-life. Although routine childhood vaccination is considered an important public health tool to combat infectious diseases, the present study associates increasing organic-Hg exposure from TM-HepB and the subsequent risk of a TD diagnosis.

  4. Pesticide exposure and lymphohaematopoietic cancers: a case-control study in an agricultural region (Larissa, Thessaly, Greece).

    Science.gov (United States)

    Kokouva, Maria; Bitsolas, Nikolaos; Hadjigeorgiou, Georgios M; Rachiotis, George; Papadoulis, Nikolaos; Hadjichristodoulou, Christos

    2011-01-04

    The causality of lymphohaematopoietic cancers (LHC) is multifactorial and studies investigating the association between chemical exposure and LHC have produced variable results. The aim of this study was to investigate the relationships between exposure to pesticides and LHC in an agricultural region of Greece. A structured questionnaire was employed in a hospital-based case control study to gather information on demographics, occupation, exposure to pesticides, agricultural practices, family and medical history and smoking. To control for confounders, backward conditional and multinomial logistic regression analyses were used. To assess the dose-response relationship between exposure and disease, the chi-square test for trend was used. Three hundred and fifty-four (354) histologically confirmed LHC cases diagnosed from 2004 to 2006 and 455 sex- and age-matched controls were included in the study. Pesticide exposure was associated with total LHC cases (OR 1.46, 95% CI 1.05-2.04), myelodysplastic syndrome (MDS) (OR 1.87, 95% CI 1.00-3.51) and leukaemia (OR 2.14, 95% CI 1.09-4.20). A dose-response pattern was observed for total LHC cases (P = 0.004), MDS (P = 0.024) and leukaemia (P = 0.002). Pesticide exposure was independently associated with total LHC cases (OR 1.41, 95% CI 1.00 - 2.00) and leukaemia (OR 2.05, 95% CI 1.02-4.12) after controlling for age, smoking and family history (cancers, LHC and immunological disorders). Smoking during application of pesticides was strongly associated with total LHC cases (OR 3.29, 95% CI 1.81-5.98), MDS (OR 3.67, 95% CI 1.18-12.11), leukaemia (OR 10.15, 95% CI 2.15-65.69) and lymphoma (OR 2.72, 95% CI 1.02-8.00). This association was even stronger for total LHC cases (OR 18.18, 95% CI 2.38-381.17) when eating simultaneously with pesticide application. Lymphohaematopoietic cancers were associated with pesticide exposure after controlling for confounders. Smoking and eating during pesticide application were identified as

  5. Malnutrition and Childhood Disability in Turkana, Kenya: Results from a Case-Control Study.

    Science.gov (United States)

    Kuper, Hannah; Nyapera, Velma; Evans, Jennifer; Munyendo, David; Zuurmond, Maria; Frison, Severine; Mwenda, Victoria; Otieno, David; Kisia, James

    2015-01-01

    Children with disabilities may be particularly vulnerable to malnutrition, as a result of exclusions and feeding difficulties. However, there is limited evidence currently available on this subject. A population-based case-control study was conducted in Turkana County, Kenya, between July and August 2013. Key informants in the community identified children aged 6 months to 10 years who they believed may have a disability. These children were screened by a questionnaire (UNICEF-Washington Group) and assessed by a paediatrician to confirm whether they had a disability and the type. Two controls without disabilities were selected per case: A sibling control (sibling nearest in age) and a neighbourhood control (nearest neighbour within one year of age). The caregiver completed a questionnaire on behalf of the child (e.g. information on feeding, poverty, illness, education), and anthropometric measures were taken. We undertook multivariable logistic and linear regression analyses to estimate the relationship between disability and malnutrition. The study included 311 cases with disabilities, 196 sibling controls and 300 neighbour controls. Children with disabilities were more likely to report a range of feeding difficulties. They were 1.6-2.9 times more likely to have malnutrition in comparison to neighbour controls or family controls, including general malnutrition (low weight for age), stunting (low height for age), low body mass index (BMI) or low mid upper arm circumference (MUAC) for age. Children with disabilities were almost twice as likely to have wasting (low weight for height) in comparison to neighbour controls (OR = 1.9, 95% CI 1.1-3.2), but this difference was not apparent compared with siblings (OR = 1.5, 95% CI 0.8-2.7). Children with disabilities also faced other exclusions. For instance those aged 5+ were much more likely not to attend school than neighbour controls (OR = 8.5, 95% CI 4.3-16.9). Children with disabilities were particularly vulnerable to

  6. Malnutrition and Childhood Disability in Turkana, Kenya: Results from a Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Hannah Kuper

    Full Text Available Children with disabilities may be particularly vulnerable to malnutrition, as a result of exclusions and feeding difficulties. However, there is limited evidence currently available on this subject.A population-based case-control study was conducted in Turkana County, Kenya, between July and August 2013. Key informants in the community identified children aged 6 months to 10 years who they believed may have a disability. These children were screened by a questionnaire (UNICEF-Washington Group and assessed by a paediatrician to confirm whether they had a disability and the type. Two controls without disabilities were selected per case: A sibling control (sibling nearest in age and a neighbourhood control (nearest neighbour within one year of age. The caregiver completed a questionnaire on behalf of the child (e.g. information on feeding, poverty, illness, education, and anthropometric measures were taken. We undertook multivariable logistic and linear regression analyses to estimate the relationship between disability and malnutrition.The study included 311 cases with disabilities, 196 sibling controls and 300 neighbour controls. Children with disabilities were more likely to report a range of feeding difficulties. They were 1.6-2.9 times more likely to have malnutrition in comparison to neighbour controls or family controls, including general malnutrition (low weight for age, stunting (low height for age, low body mass index (BMI or low mid upper arm circumference (MUAC for age. Children with disabilities were almost twice as likely to have wasting (low weight for height in comparison to neighbour controls (OR = 1.9, 95% CI 1.1-3.2, but this difference was not apparent compared with siblings (OR = 1.5, 95% CI 0.8-2.7. Children with disabilities also faced other exclusions. For instance those aged 5+ were much more likely not to attend school than neighbour controls (OR = 8.5, 95% CI 4.3-16.9.Children with disabilities were particularly

  7. Maternal complication prevention: evidence from a case-control study in southwest Nigeria

    Directory of Open Access Journals (Sweden)

    Kayode O. Osungbade

    2014-12-01

    Full Text Available Background: The importance of strengthening maternal health services as a preventive intervention for morbidities and complications during pregnancy and delivery in developing countries cannot be over-emphasised, since use of prenatal health services improves maternal health outcomes. Aim: This study investigated differences in risk factors for maternal complications in booked and unbooked pregnant women in Nigeria, and provided evidence for their prevention. Setting: The study was carried out in a postnatal ward in a secondary health facility. Methods: This was a case-control study involving booked and unbooked pregnant women who had delivered. Consecutive enrolment of all unbooked pregnant women (cases was done, and one booked pregnant woman (control was enrolled and matched for age with each of these. Both groups were interviewed using a questionnaire, whilst records of delivery were extracted from the hospital files. Findings were subjected to logistical regression at a significance level of p < 0.05. Results: Booked women had a lower median length of labour (10 hours compared to unbooked women (13 hours. More women in the booked control group (139; 35.1% than in the unbooked case group (96; 23.6% reported at least one type of morbidity during the index pregnancy (p = 0.0004. Booking status was associated with a likelihood of spontaneous vaginal delivery. Young maternal age, low education, rural residence and low socio-economic status were associated with less likelihood of using prenatal services. Young maternal age, low education and intervention in the delivery were associated with a likelihood of experiencing a complication of delivery. Conclusion: Strengthening antenatal and secondary healthcare services as short- and mediumterm measures might be cost-effective as a preventive strategy in complications of pregnancy,whilst socio-economic dimensions of health are accorded priority in the long term.

  8. Subfertility and Risk of Testicular Cancer in the EPSAM Case-Control Study.

    Science.gov (United States)

    Grasso, Chiara; Zugna, Daniela; Fiano, Valentina; Robles Rodriguez, Nena; Maule, Milena; Gillio-Tos, Anna; Ciuffreda, Libero; Lista, Patrizia; Segnan, Nereo; Merletti, Franco; Richiardi, Lorenzo

    2016-01-01

    It has been suggested that subfertility and testicular cancer share genetic and environmental risk factors. We studied both subfertility and the strongest known testicular cancer susceptibility gene, the c-KIT ligand (KITLG), whose pathway is involved in spermatogenesis. The EPSAM case-control study is comprised of testicular cancer patients from the Province of Turin, Italy, diagnosed between 1997 and 2008. The present analysis included 245 cases and 436 controls from EPSAM, who were aged 20 years or older at diagnosis/recruitment. The EPSAM questionnaire collected information on factors such as number of children, age at first attempt to conceive, duration of attempt to conceive, use of assisted reproduction techniques, physician-assigned diagnosis of infertility, number of siblings, and self-reported cryptorchidism. Genotyping of the KITLG single nucleotide polymorphism (SNP) rs995030 was performed on the saliva samples of 202 cases and 329 controls. Testicular cancer was associated with the number of children fathered 5 years before diagnosis (odds ratio (OR) per additional child: 0.78, 95% confidence interval (CI): 0.58-1.04) and sibship size (OR per additional sibling: 0.76, 95% CI: 0.66-0.88). When considering the reproductive history until 1 year before diagnosis, attempting to conceive for at least 12 months or fathering a child using assisted reproduction techniques was not associated with the risk of testicular cancer, nor was age at first attempt to conceive or physician-assigned diagnosis of infertility. The SNP rs995030 was strongly associated with risk of testicular cancer (per allele OR: 1.83; 95%CI: 1.26-2.64), but it did not modify the association between number of children and the risk of testicular cancer. This study supports the repeatedly reported inverse association between number of children and risk of testicular cancer, but it does not find evidence of an association for other indicators of subfertility.

  9. Anterior cervical spine surgery-associated complications in a retrospective case-control study

    OpenAIRE

    Tasiou, Anastasia; Giannis, Theofanis; Brotis, Alexandros G.; Siasios, Ioannis; Georgiadis, Iordanis; Gatos, Haralampos; Tsianaka, Eleni; Vagkopoulos, Konstantinos; Paterakis, Konstantinos; Fountas, Kostas N.

    2017-01-01

    Anterior cervical spine procedures have been associated with satisfactory outcomes. However, the occurrence of troublesome complications, although uncommon, needs to be taken into consideration. The purpose of our study was to assess the actual incidence of anterior cervical spine procedure-associated complications and identify any predisposing factors. A total of 114 patients undergoing anterior cervical procedures over a 6-year period were included in our retrospective, case-control study. ...

  10. Risk factors for pre-term birth in Iraq: a case-control study

    Directory of Open Access Journals (Sweden)

    Al-Dabbagh Samim A

    2006-04-01

    Full Text Available Abstract Background Preterm birth (PTBis a major clinical problem associated with perinatal mortality and morbidity. The aim of the present study is to identify risk factors associated with PTB in Mosul, Iraq. Methods A case-control study was conducted in Mosul, Iraq, from 1st September, 2003 to 28th February, 2004. Results A total of 200 cases of PTB and 200 controls of full-term births were screened and enrolled in the study. Forward logistic regression analysis was used in the analysis. Several significant risk associations between PTB and the following risk factors were identified: poor diet (OR = 4.33, heavy manual work (OR = 1.70, caring for domestic animals (OR = 5.06, urinary tract infection (OR = 2.85, anxiety (OR = 2.16, cervical incompetence (OR = 4.74, multiple pregnancies (OR = 7.51, direct trauma to abdomen (OR = 3.76 and abortion (OR = 6.36. Conclusion The main determinants of PTB in Iraq were low socio-economic status and factors associated with it, such as heavy manual work and caring for domestic animals, in addition to urinary tract infections and poor obstetric history.

  11. Association between Myocardial Infarction and Periodontitis: a Meta-Analysis of Case-Control Studies

    Directory of Open Access Journals (Sweden)

    Quan Shi

    2016-11-01

    Full Text Available AbstractBackground and Objective: Many clinical researches have been carried out to investigate the relationship between myocardial infarction (MI and periodontitis. Despite most of them indicated that the periodontitis may be associated with an increased risk of MI, the findings and study types of these studies have been inconsistent. The goal of this meta-analysis was to critically assess the strength of the association between MI and periodontitis in case-control studies.Methods: PubMed and the Cochrane Library were searched for eligible case-control studies reporting relevant parameters that compared periodontal status between MI and control subjects. The odds ratios (ORs and 95% confidence intervals (CIs from each study were pooled to estimate the strength of the association between MI and periodontitis. The mean differences and 95% CIs for periodontal-related parameters were calculated to determine their overall effects.Results: Seventeen studies including a total of 3456 MI patients and 3875 non-MI control subjects were included. The pooled OR for the association between MI and periodontitis was 2.531 (95% CI: 1.927-3.324. The mean differences (95% CIs for clinical attachment loss, probing depth, bleeding on probing, plaque index, and the number of missing teeth were 1.000 (0.726-1.247, 1.209 (0.538-1.880, 0.342 (0.129-0.555, 0.383 (0.205-0.560, and 4.122 (2.012-6.232, respectively. Conclusion: With the current evidence, the results support the presence of a significant association between MI and periodontitis. Moreover, MI patients had worse periodontal and oral hygiene status and fewer teeth than did control subjects. More high-quality and well-designed studies focusing on the casual relationship between MI and periodontitis should be conducted in the future.

  12. Association between group A beta-haemolytic streptococci and vulvovaginitis in adult women: a case-control study.

    Science.gov (United States)

    Bruins, M J; Damoiseaux, R A M J; Ruijs, G J H M

    2009-08-01

    Guidelines for the management of vaginal discharge mention Candida albicans, Trichomonas vaginalis, bacterial vaginosis, Chlamydia trachomatis and Neisseria gonorrhoeae as causes and do not recommend full microbiological culture. The role of non-group B beta-haemolytic streptococci in vaginal cultures is unclear, except for group A streptococci that are known to cause vulvovaginitis in children. In a case-control study, we investigated the association between non-group B beta-haemolytic streptococci and vulvovaginitis in adult women. Cases were women with recurrent vaginal discharge from whom a sample was cultured. Controls were asymptomatic women who consented to submitting a vaginal swab. Group A streptococci were isolated from 49 (4.9%) of 1,010 cases and not from the 206 controls (P < 0.01). Isolation rates of group C, F and G streptococci were low and did not differ statistically between cases and controls. Group A beta-haemolytic streptococci are associated with vaginal discharge in adult women. The other non-group B streptococci require more study. For the adequate management of vaginal discharge, culturing is necessary if initial treatment fails. Guidelines should be amended according to these results.

  13. Ultrasound biomicroscopy and iris pigment dispersion: a case--control study.

    Science.gov (United States)

    Mora, P; Sangermani, C; Ghirardini, S; Carta, A; Ungaro, N; Gandolfi, Sa

    2010-04-01

    The study involved eyes affected by pigment dispersion syndrome (PDS) or pigmentary glaucoma (PG) investigated by ultrasound biomicroscopy (UBM). Different irido-corneal parameters were assessed and compared with those from healthy controls. The aim was to investigate the capacity of the UBM in differentiating the cases and, potentially, in confirming the pathogenic mechanisms. Patients with a first diagnosis of PDS or PG were included. A cohort of healthy volunteers matched for sex, age and refractive errors was recruited. All underwent UBM examination: the following parameters were assessed in relaxed and stimulated accommodative state in one eye: iris-lens contact (ILC), irido-corneal angle (ICA) and iris concavity (IC). A receiver operating characteristic (ROC) analysis assessed the ability of UBM to discriminate between subjects with and without PDS/PG. There were 24 eyes in the case group: four diagnosed as PG and the remaining 20 as PDS. There were 25 eyes in the control group. The two groups were statistically superimposable except for baseline intraocular pressure, which was higher in the case group (p=0.0001). All UBM parameters were statistically different between the two groups. ICA in near vision was the best-performing parameter, reaching a sensitivity (=specificity) of 0.875 with a cut-off at 53.0 degrees . The second most sensitive parameter was IC, still in near vision. All UBM parameters examined were statistically different between the two groups. ROC analysis showed ICA and IC in near vision to be the most discriminatory parameters. This evidence confirms the importance of iris movements in inducing the particular features of PDS/PG.

  14. Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer.

    Science.gov (United States)

    Dobrzynski, Ludwik; Fornalski, Krzysztof W; Reszczynska, Joanna

    2018-03-01

    A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.

  15. Are dietary reports in a case-control study on thyroid cancer biased by risk perception of Chernobyl fallout?

    Science.gov (United States)

    Xhaard, C; Dumas, A; Souchard, V; Ren, Y; Borson-Chazot, F; Sassolas, G; Schvartz, C; Colonna, M; Lacour, B; Wonoroff, A S; Velten, M; Clero, E; Maillard, S; Marrer, E; Bailly, L; Mariné Barjoan, E; Schlumberger, M; Orgiazzi, J; Adjadj, E; Rubino, C; Bouville, A; Drozdovitch, V; de Vathaire, F

    2017-08-01

    In retrospective case-control studies performed following nuclear tests or nuclear accidents, individual thyroid radiation dose reconstructions are based on fallout and meteorological data from the residential area, demographic characteristics, and lifestyle as well as dietary information. Collecting the latter is a controversial step, as dietary declarations may be affected by the subjects' beliefs about their risk behavior. This report analyses the potential for such bias in a case-control study performed in eastern France. The study included 765 cases of differentiated thyroid carcinoma matched with 831 controls. Risk perceptions and beliefs of cases and controls were compared using Chi 2 tests and differences in dietary reports were analyzed using a two-way ANOVA. In general, atmospheric pollution and living near a nuclear power plant were the two major risks that may influence thyroid cancer occurrence cited by cases and controls. When focusing in particular on the consequences of the Chernobyl accident, cases were more likely to think that the consequences were responsible for thyroid cancer occurrence than controls. Vegetable consumption during the two months after the Chernobyl accident was correlated with the status of subjects, but not to their beliefs. Conversely, consumption of fresh dairy products was not correlated with the status or beliefs of subjects. We found no evidence of systematic bias in dietary reports according to the status or beliefs held by subjects about the link between thyroid cancer occurrence and Chernobyl fallout. As such, these dietary reports may be used in further studies involving individual dosimetric reconstructions. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. [Domestic and family violence against women: a case-control study with victims treated in emergency rooms].

    Science.gov (United States)

    Garcia, Leila Posenato; Duarte, Elisabeth Carmen; Freitas, Lúcia Rolim Santana de; Silva, Gabriela Drummond Marques da

    2016-01-01

    This study aimed to identify factors associated with treatment of victims of domestic and family violence in emergency rooms in Brazil. This is a case-control study based on the Surveillance System for Violence and Accidents (VIVA), 2011. Women ≥ 18 years who were victims of family and domestic violence were selected as cases and compared to accident victims (controls). Adjusted odds ratios were estimated by unconditional logistic regression. 623 cases and 10,120 controls were included. Risk factors according to the adjusted analysis were younger age (18-29 years), low schooling, lack of paid work, alcohol consumption, having sought treatment in a different health service, and violence on weekends or at night or in the early morning hours. The study concludes that domestic and family violence shows alcohol consumption as a strongly associated factor. Days and hours with the highest ocurrence reveal the need to adjust emergency services to treat victims.

  17. Attention deficit hyperactivity disorder in children with primary monosymptomatic nocturnal enuresis: A case-control study

    Directory of Open Access Journals (Sweden)

    Parsa Yousefichaijan

    2016-01-01

    Full Text Available Attention deficit hyperactivity disorder (ADHD is one of the most common childhood neurological disorders. The aim of this study was to investigate ADHD in children with primary monosymptomatic nocturnal enuresis (PMNE and compare it with healthy children. A total of 100 five to 16-year-old children with PMNE and 100 healthy children without NE were included in this case-control study as the cases and control groups, respectively. Subjects were selected from children who were referred to the pediatric clinic of the Amir Kabir Hospital of Arak, Iran, based on inclusion and exclusion criteria. ADHD was diagnosed by Conner′s Parent Rating Scale-48 and the Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria and was confirmed by consultation with a psychiatrist. Data were analyzed by binomial test using SPSS18. ADHD inattentive type was observed in 16 cases (16% with PMNE and five controls (5% (P = 0.01. Despite these significant differences in the case and control groups, 25 (25% and 16 (16% children were affected by ADHD hyperactive-impulsive type (P = 0.08 and 15 (15% and 16 (16% children were affected by ADHD mixed type (P = 0.84, respectively. ADHD inattentive type in children with PMNE was significantly more common than that in healthy children. The observed correlation between ADHD inattentive type and PMNE makes psychological counseling mandatory in children with PMNE.

  18. Population versus hospital controls in the assessment of dietary intake of isoflavone for case-control studies on cancers in China.

    Science.gov (United States)

    Li, Lin; Zhang, Min; Holman, C D'Arcy J

    2013-01-01

    To assess dietary isoflavone intake between population and hospital outpatient controls and examine if cancer risks estimated for isoflavone using hospital outpatient controls would be different from those using population controls. Three parallel case-control studies on leukemia, breast, and colorectal cancers in China in 2009-2010 were conducted, using population and hospital outpatient controls to separately match 560 incident cases at a 1:1 ratio. A validated food frequency questionnaire was administered by face-to-face interview. Conditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The 2 control groups had closely similar distributions of dietary isoflavone intake. Risk estimates for breast cancers were adjusted ORs (95% CI) of 0.39 (0.23-0.66) and 0.31 (0.18-0.55) for daidzein, 0.35 (0.20-0.61) and 0.28 (0.16-0.52) for genistein, 0.66 (0.41-1.08) and 0.53 (0.32-0.88) for glycitein, and 0.53 (0.33-0.85) and 0.43 (0.26-0.71) for total isoflavone using hospital outpatient and population controls respectively. The study found that hospital outpatient controls were comparable to population controls in measured dietary intake of isoflavone in the Chinese hospital setting.

  19. Acoustic neuroma risk in relation to mobile telephone use: Results of the INTERPHONE international case-control study

    DEFF Research Database (Denmark)

    Berg-Beckhoff, Gabi

    2011-01-01

    Background: The rapid increase in mobile telephone use has generated concern about possible health risks of radiofrequency electromagnetic fields from these devices. Methods: A case-control study of 1105 patients with newly diagnosed acoustic neuroma (vestibular schwannoma) and 2145 controls...... was conducted in 13 countries using a common protocol. Past mobile phone use was assessed by personal interview. In the primary analysis, exposure time was censored at one year before the reference date (date of diagnosis for cases and date of diagnosis of the matched case for controls); analyses censoring...

  20. Characterization of the polysensitized patient: a matched case-control study

    DEFF Research Database (Denmark)

    Carlsen, Berit Christina; Andersen, Klaus Ejner; Menné, Torkil

    2009-01-01

    for polysensitization, including atopic eczema. METHODS: A questionnaire case-control study of 562 polysensitized and 1124 single/double-sensitized individuals was performed. RESULTS: The results show that 45% of polysensitized and 31% of single/double-sensitized patients had or had had atopic eczema, and atopic eczema...... the group of patients with atopic eczema and the group without atopic eczema. CONCLUSION: Patients with atopic eczema were overrepresented in the group of polysensitized patients and polysensitized patients should be viewed in the light of occurrence or lack of atopic eczema....

  1. Effects of environmental factors on child survival in Bangladesh: a case control study.

    Science.gov (United States)

    Hoque, B A; Chakraborty, J; Chowdhury, J T; Chowdhury, U K; Ali, M; el Arifeen, S; Sack, R B

    1999-03-01

    The need for further studies on relationships between deaths and environmental variables has been reported in the literature. This case-control study was, therefore, carried out to find out the associations between several social and environmental variables and deaths of children due to infectious diseases such as those leading to diarrhoea, acute respiratory infection, measles and other diseases. Six hundred and twenty-five deaths (cases) and an equal number of matched living children (controls) aged 1-59 months, were studied in rural Matlab. An analysis of crude and adjusted odds ratio showed differential associations. Sources of drinking water, amount of stored water, conditions of latrines, number of persons sleeping with the child and the type of cooking site were statistically significantly associated with deaths due to infectious diseases after controlling for breast feeding, immunization, and the family size. Significant associations were also observed between: (i) the sources of drinking water and deaths due to ARI, and (ii) conditions of latrines and deaths due to diarrhoeal diseases, after controlling for the confounding variables. Several other environmental factors also showed associations with these various death groups, but they were not statistically significant. The size of the samples in death groups (small) and the prevalence of more or less homogeneous environmental health conditions probably diminished the magnitude of the effects. The results of the study reconfirm the importance of environmental health intervention in child survival, irrespective of breast-feeding, immunization, and selected social variables.

  2. Risk factors for tuberculosis among health care workers in South India: a nested case-control study.

    Science.gov (United States)

    Mathew, Anoop; David, Thambu; Thomas, Kurien; Kuruvilla, P J; Balaji, V; Jesudason, Mary V; Samuel, Prasanna

    2013-01-01

    The epidemiology of tuberculosis (TB) among health care workers (HCWs) in India remains under-researched. This study is a nested case-control design assessing the risk factors for acquiring TB among HCWs in India. It is a nested case-control study conducted at a tertiary teaching hospital in India. Cases (n = 101) were HCWs with active TB. Controls (n = 101) were HCWs who did not have TB, randomly selected from the 6,003 subjects employed at the facility. Cases and controls were compared with respect to clinical and demographic variables. The cases and controls were of similar age. Logistic regression analysis showed that body mass index (BMI) <19 kg/m(2) (odds ratio [OR]: 2.96, 95% confidence interval [CI]: 1.49-5.87), having frequent contact with patients (OR: 2.83, 95% CI: 1.47-5.45) and being employed in medical wards (OR: 12.37, 95% CI: 1.38-110.17) or microbiology laboratories (OR: 5.65, 95% CI: 1.74-18.36) were independently associated with increased risk of acquiring TB. HCWs with frequent patient contact and those with BMI <19 kg/m(2) were at high risk of acquiring active TB. Nosocomial transmission of TB was pronounced in locations, such as medical wards and microbiology laboratories. Surveillance of high-risk HCWs and appropriate infrastructure modifications may be important to prevent interpersonal TB transmission in health care facilities. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Toxocara infection in psychiatric inpatients: a case control seroprevalence study.

    Directory of Open Access Journals (Sweden)

    Cosme Alvarado-Esquivel

    Full Text Available BACKGROUND: There is poor knowledge about the epidemiology of toxocariasis in psychiatric patients. AIMS: Determine the seroepidemiology of Toxocara infection in psychiatric patients. METHODS: Through a case-control seroprevalence study, 128 psychiatric inpatients and 276 control subjects were compared for the presence of anti-Toxocara IgG antibodies in Durango, Mexico. Socio-demographic, clinical, and behavioral characteristics of inpatients associated with toxocariasis were also investigated. RESULTS: Six of the 128 (4.7% psychiatric inpatients, and 3 (1.1% of the 276 controls were positive for anti-Toxocara IgG antibodies (P = 0.03. Stratification by age showed that Toxocara seroprevalence was significantly (P = 0.02 higher in patients aged ≤50 years old (6/90∶6.7% than controls of the same age (2/163∶1.2%. While Toxocara seroprevalence was similar in patients and controls aged >50 years old. Stratification by gender showed that Toxocara seroprevalence was significantly (P = 0.03 higher in female patients (2/37∶5.4% than in female controls (0/166∶0%. No statistically significant associations between Toxocara seropositivity and clinical characteristics were found. In contrast, Toxocara seropositivity was associated with consumption of goat meat and raw sea snail. CONCLUSIONS: This is the first report of toxocariasis in psychiatric inpatients in Mexico. Further studies with larger sample sizes are needed to elucidate the association of toxocariasis with psychiatric diseases. The role of the consumption of goat meat and raw sea snail in the transmission of Toxocara deserve further investigation.

  4. The Mortality Penalty of Incarceration: Evidence from a Population-based Case-control Study of Working-age Males.

    Science.gov (United States)

    Pridemore, William Alex

    2014-06-01

    There is a growing body of research on the effects of incarceration on health, though there are few studies in the sociological literature of the association between incarceration and premature mortality. This study examined the risk of male premature mortality associated with incarceration. Data came from the Izhevsk (Russia) Family Study, a large-scale population-based case-control design. Cases (n = 1,750) were male deaths aged 25 to 54 in Izhevsk between October 2003 and October 2005. Controls (n = 1,750) were selected at random from a city population register. The key independent variable was lifetime prevalence of incarceration. I used logistic regression to estimate mortality odds ratios, controlling for age, hazardous drinking, smoking status, marital status, and education. Seventeen percent of cases and 5 percent of controls had been incarcerated. Men who had been incarcerated were more than twice as likely as those who had not to experience premature mortality (odds ratio = 2.2, 95 percent confidence interval: 1.6-3.0). Relative to cases with no prior incarceration, cases who had been incarcerated were more likely to die from infectious diseases, respiratory diseases, non-alcohol-related accidental poisonings, and homicide. Taken together with other recent research, these results from a rigorous case-control design reveal not only that incarceration has durable effects on illness, but that its consequences extend to a greater risk of early death. I draw on the sociology of health literature on exposure, stress, and social integration to speculate about the reasons for this mortality penalty of incarceration. © American Sociological Association 2014.

  5. [Risk factors associated with leg erysipelas (cellulitis) in sub-Saharan Africa: A multicentre case-control study].

    Science.gov (United States)

    Pitché, P; Diatta, B; Faye, O; Diané, B-F; Sangaré, A; Niamba, P; Mandengue, C; Kobengue, L; Saka, B; Diop, A; Ly, F; Dieng, M-T; Dicko, A; Soumah, M-M; Cissé, M; Kourouma, S-H; Kouassi, Y-I; Boukari, T; Akakpo, S; Tchangaï-Walla, K

    2015-11-01

    Acute bacterial cellulitis of the leg (erysipelas) is a common problem involving considerable morbidity in dermatology practice in Africa. Previous studies conducted in Europe and North Africa have highlighted lymphoedema and toe-web intertrigo as independent factors associated with leg erysipelas. The aim of this case-control study was to identify risk factors associated with leg erysipelas in sub-Saharan Africa, within a different socio-economic and culture context. We conducted a prospective case-control study in hospital dermatology departments in 8 sub-Saharan African countries over a 12-month period (October 2013 to September 2014). Each case of acute leg cellulitis was matched with 2 controls for age (±5 years) and sex. We analysed the general and local factors. During the study period, 364 cases (223 female, 141 male) were matched with 728 controls. The mean age was 42.15±15.15 years for patients and 42.11±36 years for controls. Multivariate analysis showed the following to be independent risk factors associated with leg erysipelas in our study: obesity (odds ratio [OR]=2.82 ; 95% confidence interval: 2.11-3.76), lymphoedema (OR=3.87, 95%CI: 2.17-6.89), voluntary cosmetic depigmentation (OR=4.29, 95%CI: 2.35-7.83), neglected traumatic wound (OR=37.2, 95%CI: 24.9-57.72) and toe-web intertrigo (OR=37.86, 95%CI: 22.27-64.5). The results of this study confirms the major role of local risk factors (toe-web intertrigo, lymphoedema) previously identified in other geographical settings. However, the originality of our study consists of the identification of voluntary cosmetic depigmentation as a risk factor for leg erysipelas in sub-Saharan Africa. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Differentiation of African components of ancestry to stratify groups in a case-control study of a Brazilian urban population.

    Science.gov (United States)

    Silbiger, Vivian N; Hirata, Mario H; Luchessi, Andre D; Genvigir, Fabiana D V; Cerda, Alvaro; Rodrigues, Alice C; Willrich, Maria A V; Arazi, Simone S; Dorea, Egidio L; Bernik, Marcia M S; Faludi, Andre A; Bertolami, Marcelo C; Santos, Carla; Carracedo, Angel; Salas, Antonio; Freire, Ana; Lareu, Maria Victoria; Phillips, Christopher; Porras-Hurtado, Liliana; Fondevila, Manuel; Hirata, Rosario D C

    2012-06-01

    Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case-control association study of a Brazilian urban sample. One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA 0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers.

  7. Risk of malignant neoplasms in acromegaly: a case-control study.

    Science.gov (United States)

    Wolinski, K; Stangierski, A; Dyrda, K; Nowicka, K; Pelka, M; Iqbal, A; Car, A; Lazizi, M; Bednarek, N; Czarnywojtek, A; Gurgul, E; Ruchala, M

    2017-03-01

    Acromegaly is a chronic disease resulting from pathological oversecretion of growth hormone and subsequently insulin growth factor-1. Several complications of the disease have been reported, including cardiovascular diseases, respiratory disorders but also increased risk of benign and malignant neoplasms. The aim of the study was to evaluate the risk of malignant neoplasms in the patients with acromegaly in comparison with the control group. Medical documentation of acromegalic patients treated in one medical center between 2005 and 2016 has been analyzed. Results were compared with sex- and age-matched group of subjects with prolactinomas and hormonally inactive pituitary lesions hospitalized in the same department. Two hundred patients with acromegaly were included. Control group was composed of 145 patients. Any malignant neoplasm in anamnesis was present in 27 (13.5 %) patients with acromegaly and six (4.1 %) subjects from control group (p = 0.003). Thyroid cancer was present in 14 (7.0 %) patients with acromegaly and two (1.4 %) in control group (p = 0.02). Breast cancer was present in seven women (5.4 % of women) in acromegaly group but none of subjects in control group (p = 0.02). Colon cancer-4 (2.0 %) patients in acromegaly group and 0 in control group (p = 0.14). Malignant neoplasms are significantly more common in patients with acromegaly. Particularly, risk of thyroid cancer was increased over fivefold. Systematic screening for neoplastic diseases should be important part of follow-up in these patients. Further case-control studies are strongly indicated to evaluate which neoplasms are more common in acromegalic patients and what is the exact risk of malignancy.

  8. A case-control study of risk factors for multiple sclerosis in Iran.

    Science.gov (United States)

    Alonso, Alvaro; Cook, Stuart D; Maghzi, Amir-Hadi; Divani, Afshin A

    2011-05-01

    Numerous studies have assessed risk factors for multiple sclerosis (MS), although none have been conducted previously in Iran. The objective of this study was to study lifestyle and environmental risk factors of MS in the Iranian population. A case-control study, including 394 MS cases and 394 matched controls, was conducted in MS clinics in different Iranian cities. Information on lifestyles, environmental exposures, and past medical history was obtained from medical charts and phone interviews. In multivariable analysis, sunlight exposure was associated with a lower risk of MS: the odds ratio (OR) and 95% confidence interval (CI) of MS associated with a 1-h increment in daily sunlight was 0.62 (0.53-0.73). Smoking was associated with MS risk in women (OR: 6.48, 95% CI: 1.46-28.78), but not in men (OR: 0.72, 95% CI: 0.31-1.68) (p=0.002 for interaction). Finally, past history of common surgical procedures, infectious disorders, or exposure to pets and farm animals was not associated with MS risk. Different modifiable lifestyles, including sunlight exposure and smoking, were associated with lower MS risk in Iran. Interventions aimed at promoting smoking cessation and, more importantly, at increasing exposure to sunlight might contribute to the prevention of MS.

  9. Birth outcomes of male and female patients with infantile hypertrophic pyloric stenosis--a population-based case-control study.

    Science.gov (United States)

    Vermes, Gabor; Mátrai, Ákos; Czeizel, Andrew E; Ács, Nándor

    2016-01-01

    Most of the patients are affected by isolated infantile hypertrophic pyloric stenosis (IHPS) beyond the polygenic predisposition, the other factors in the multifactorial etiology are largely unknown. The main characteristic of IHPS is the robust male predominance, thus the aim of this study was to analyze birth outcomes in males and females whether they are different or not. The study samples included 241 cases with IHPS, 357 matched, and 38,151 population controls without any defect in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. The findings of this case-control study confirmed the well-known strong male excess (85.5%). The mean gestational age was somewhat longer and it is associated with a lower rate of preterm births. Mean birth weight did not show significant differences among the study groups, but the rate of low birthweight was higher in cases with IHPS. However, these differences were found only in males. Thus, intrauterine fetal growth restriction is characteristic only for male cases with IHPS. Our study confirmed the well-known obvious male excess of cases with IHPS, but our findings suggest some differences in birth outcomes of male and female cases. Male cases with IHPS had intrauterine fetal growth restriction while females did not. These data may indicate some differences in the pathogenesis of IHPS in males and females.

  10. Lack of Serological and Molecular Association between Toxoplasma Gondii Exposure and Obesity: A Case-Control Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Maldonado-Soto, Edith; Sanchez-Anguiano, Luis Francisco; Hernandez-Tinoco, Jesus; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Sandoval-Carrilo, Ada Agustina; Salas-Pacheco, Jose Manuel; Antuna-Salcido, Elizabeth Irasema; Estrada-Martinez, Sergio; Guido-Arreola, Carlos Alberto

    2017-01-01

    The association between T. gondii infection and obesity has been scantly studied. Through an age-, and gender-matched case-control study, we determined the association of T. gondii infection and obesity using serological and molecular methods. Cases included 203 persons with obesity, and controls included 203 persons without obesity. Participants were tested for the presence of anti-Toxoplasma IgG antibodies using an enzyme-linked immunoassay (EIA). IgG seropositive individuals were further tested for the presence of anti-T. gondii IgM antibodies using an EIA, and T. gondii DNA by polymerase chain reaction (PCR). Anti-T. gondii IgG antibodies were found in 16 (7.9%) of the 203 cases and in 18 (8.9%) of the 203 controls (OR=0.87; 95% CI: 0.43-1.77; P=0.72). One (6.3%) of the 16 anti-T. gondii IgG seropositive cases and 6 (33.3%) of the 18 anti-T. gondii IgG seropositive controls were positive for IgM (P=0.09). Mean body mass index (35.5 ± 4.5) in T. gondii seropositive cases was similar (P=0.57) to that (36.1 ± 4.5) found in T. gondii seronegative cases. Stratification by obesity classes (I, II, and III) did not reveal differences (P>0.05) in seroprevalences (7.8%, 7.9%, and 8.1%, respectively) or high (>150 IU/ml) IgG antibody levels (3.3%, 3.9%, and 2.7%, respectively). PCR was positive in 5 (31.3%) of 16 cases, and in 5 (27.8%) of 18 controls examined (P=1.0). We found no serological or molecular evidence of an association between T. gondii infection and obesity in people attending a public health center in the northern Mexican city of Durango. PMID:28824343

  11. Risk factors for chronic periodontitis in Sri Lankan adults: a population based case-control study.

    Science.gov (United States)

    Wellapuli, Nimali; Ekanayake, Lilani

    2017-09-07

    To determine risk factors for chronic periodontitis in 30-60 year olds in Sri Lanka. Cases and controls for this population based unmatched case-control study were identified from a broader cross-sectional study which was conducted to determine the prevalence of chronic periodontitis in 30-60 year old adults in Colombo district Sri Lanka. The study included 694 cases and 706 controls. Data were collected by means of a pre-tested interviewer administered questionnaire to obtain information about socio-demographic and behavioural factors, a physical examination to record anthropometric measurements and an oral examination. Being a male, a Muslim, belonging to the 45-60 year old age group, having less than 12 years of education, using the finger to clean teeth, current smoking, current betel quid chewing, self-reported diabetes and hypertension emerged as risk factors for chronic periodontitis. Several socio-demographic and behavioural factors as well as co-morbid conditions emerged as independent risk factors for chronic periodontits in this population. The findings could be used for planning programmes to reduce the burden of chronic periodontits in Colombo district Sri Lanka.

  12. Vitamin E Intake and Risk of Renal Cell Carcinoma: A Meta-Analysis of 7 Case-Control Studies.

    Science.gov (United States)

    Shang, Yonggang; Yi, Shanhong; Cui, Dong; Han, Guangwei; Liu, Chengcheng

    2015-07-01

    Vitamin E intake may reduce the risk of renal cell carcinoma, but the results were inconsistent. Hence, we conducted a meta-analysis to assess the association between dietary vitamin E intake and the risk of renal cell carcinoma. We searched PubMed to identify the relevant case-control studies up to June 2014. Reference lists of retrieved articles were also reviewed. Odds ratios and corresponding 95% confidence intervals were used to estimate the association between dietary vitamin E intake and the risk of renal cell carcinoma. We identified 7 case-control studies regarding dietary vitamin E intake and risk of renal cell carcinoma, involving 5789 cases and 14866 controls. The odds ratio of renal cell carcinoma for the highest compared with the lowest dietary vitamin E intake was 0.75 (95% confidence interval: 0.59-0.91), and heterogeneity was observed across studies. The association between dietary vitamin E intake and the risk of renal cell carcinoma was not significantly differed by gender, but this association were inconsistent in the North American and European populations. Our study provided a evidence that there was a significant inverse association of dietary vitamin E intake with risk of renal cell carcinoma. However, this finding was based on the case-control studies, more well-designed cohort studies are needed. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  13. Online market research panel members as controls in case-control studies to investigate gastrointestinal disease outbreaks: early experiences and lessons learnt from the UK.

    Science.gov (United States)

    Mook, P; McCormick, J; Kanagarajah, S; Adak, G K; Cleary, P; Elson, R; Gobin, M; Hawker, J; Inns, T; Sinclair, C; Trienekens, S C M; Vivancos, R; McCarthy, N D

    2018-03-01

    Established methods of recruiting population controls for case-control studies to investigate gastrointestinal disease outbreaks can be time consuming, resulting in delays in identifying the source or vehicle of infection. After an initial evaluation of using online market research panel members as controls in a case-control study to investigate a Salmonella outbreak in 2013, this method was applied in four further studies in the UK between 2014 and 2016. We used data from all five studies and interviews with members of each outbreak control team and market research panel provider to review operational issues, evaluate risk of bias in this approach and consider methods to reduce confounding and bias. The investigators of each outbreak reported likely time and cost savings from using market research controls. There were systematic differences between case and control groups in some studies but no evidence that conclusions on the likely source or vehicle of infection were incorrect. Potential selection biases introduced by using this sampling frame and the low response rate are unclear. Methods that might reduce confounding and some bias should be balanced with concerns for overmatching. Further evaluation of this approach using comparisons with traditional methods and population-based exposure survey data is recommended.

  14. Robust Tests for Additive Gene-Environment Interaction in Case-Control Studies Using Gene-Environment Independence

    DEFF Research Database (Denmark)

    Liu, Gang; Lee, Seunggeun; Lee, Alice W

    2018-01-01

    test with case-control data. Our simulation studies suggest that the EB approach uses the gene-environment independence assumption in a data-adaptive way and provides power gain compared to the standard logistic regression analysis and better control of Type I error when compared to the analysis......There have been recent proposals advocating the use of additive gene-environment interaction instead of the widely used multiplicative scale, as a more relevant public health measure. Using gene-environment independence enhances the power for testing multiplicative interaction in case......-control studies. However, under departure from this assumption, substantial bias in the estimates and inflated Type I error in the corresponding tests can occur. This paper extends the empirical Bayes (EB) approach previously developed for multiplicative interaction that trades off between bias and efficiency...

  15. A case-control study on risk factors of breast cancer in Han Chinese women.

    Science.gov (United States)

    Liu, Li-Yuan; Wang, Fei; Cui, Shu-De; Tian, Fu-Guo; Fan, Zhi-Min; Geng, Cui-Zhi; Cao, Xu-Chen; Yang, Zhen-Lin; Wang, Xiang; Liang, Hong; Wang, Shu; Jiang, Hong-Chuan; Duan, Xue-Ning; Wang, Hai-Bo; Li, Guo-Lou; Wang, Qi-Tang; Zhang, Jian-Guo; Jin, Feng; Tang, Jin-Hai; Li, Liang; Zhu, Shi-Guang; Zuo, Wen-Shu; Yu, Li-Xiang; Xiang, Yu-Juan; Zhou, Fei; Li, Liang; Zhang, Qiang; Fu, Qin-Ye; Ma, Zhong-Bing; Gao, De-Zong; Li, Yu-Yang; Liu, Lu; Ye, Chun-Miao; Wang, Yong-Jiu; Zhou, Wen-Zhong; Yu, Zhi-Gang

    2017-11-14

    This study aimed to investigate risk factors associated with breast cancer among Han Chinese women in northern and eastern China. A matched case-control study involving 1489 patients with breast cancer and 1489 controls was conducted across 21 hospitals in 11 provinces in China, from April 2012 to April 2013. We developed a structured questionnaire to record information from face-to-face interviews with participants. Student's t-tests, Pearson's chi-square tests, and univariate and multivariate conditional logistic regression analyses were used to identify variables with significant differences between the case and control groups. Ten variables were identified (P ratio, menopause, family history of breast cancer, present life satisfaction, sleep satisfaction, milk products, behavior prevention scores, and awareness of breast cancer. We identified a comprehensive range of factors related to breast cancer, among which several manageable factors may contribute to breast cancer prevention. Further prospective studies concerning psychological interventions, sleep regulation, health guidance, and physical exercise are required. A screening model for high-risk populations should be put on the agenda.

  16. Similarities and differences among paramilitaries, severe aggressors and communal control, a case-control study in Medellín, Colombia

    Directory of Open Access Journals (Sweden)

    Luis F. Duque

    2007-08-01

    Full Text Available A case-control study was performed in Medellín during 2003-2004 to compare characteristics of severe aggressors, members of Colombian United Selfdefense Forces members (AUC, otherwise named paramilitaries, and communal control. Severe aggressors and paramilitaries have lower educational level than communal control; their families were biparental in a lower proportion, and experienced drug and alcohol abuse in a higher proportion than in the case of families of communal control. Severe aggressors and paramilitaries’ families suffered forced displacement and assassination of one of its members in a higher proportion than those of controls. There were no differences relating time of residence in Medellín or current neighborhood, or current family socioeconomic stressors. No differences were found regarding believing in God, religious practice and reasons for practicing religion. There were no significant differences for all mentioned variables between severe aggressors and paramilitaries. Paramilitaries did inform having suffered extreme poverty conditions during childhood in a higher proportion than severe aggressors and controls. Progress opportunities perception was also explored.

  17. Risk factors for the occurrence of undifferentiated carcinoma of nasopharyngeal type: A case-control study

    Directory of Open Access Journals (Sweden)

    Nešić Vladimir

    2010-01-01

    Full Text Available Introduction. The incidence rate of nasopharyngeal carcinoma in Serbia is less than one per 100,000 citizens, which classifies it as a region with low incidence for this disease. Objective. The aim of this study was to test some hypotheses of the risk factors for undifferentiated carcinoma of nasopharyngeal type (UCNT in the low incidence population. Methods. A case-control study was used for the research. The study included 45 cases with histopathological diagnosis of UCNT and 90 controls. Cases and the controls were individually matched by sex, age (±3 years, and place of residence (city-village. Data were gathered about sociodemographic characteristics, occupational exposure to harmful agents, habits, diet, personal history, and family history. In the analysis of the data, conditional univariate and multivariate logistic regression analyses were applied. Results. According to the results of multivariate logistic regression analysis UCNT was significantly positively associated with 'passive smoking' of tobacco in the family during childhood, frequent consumption of industrially manufactured food additives for enhancing flavour and frequent consumption of white bread. UCNT was significantly negatively associated with frequent consumption of margarine, olive oil and cornbread. Conclusion. In our low incidence population, an independent risk factor for the occurrence of UCNT was 'passive smoking' of tobacco in the family during childhood, use of industrially manufactured food with additives for enhancing flavour and consumption of white bread. Multicentric study enrolling a greater number of cases would be desirable.

  18. Normal endothelial function in patients with mild-to-moderate psoriasis: a case-control study

    DEFF Research Database (Denmark)

    Jensen, Peter R; Zachariae, Claus; Hansen, Peter

    2011-01-01

    Evidence is increasing that severe psoriasis is an independent cardiovascular risk factor. Results from case-control studies of endothelial dysfunction, a marker of early atherosclerosis, in patients with moderate-to-severe psoriasis have been conflicting and were conducted with operator-dependen......Evidence is increasing that severe psoriasis is an independent cardiovascular risk factor. Results from case-control studies of endothelial dysfunction, a marker of early atherosclerosis, in patients with moderate-to-severe psoriasis have been conflicting and were conducted with operator......-dependent and technically demanding ultrasound measurement of brachial artery flow-mediated vasodilation. Therefore, we decided to measure endothelial function and other cardiovascular risk factors in patients with mild-to-moderate psoriasis (n = 30) and controls (n = 30) using a newer and relatively operator......-independent technique. No difference was detected between the groups with regards to endothelial function. However, despite the patients experiencing rather mild psoriasis they did exhibit higher levels of certain cardiovascular risk factors, including waist circumference, resting heart rate, systolic and diastolic...

  19. Maternal periodontal disease and preterm birth: A case-control study

    Directory of Open Access Journals (Sweden)

    Pushpalatha Govindaraju

    2015-01-01

    Full Text Available Background and Objective: Preterm birth (PTB is an important issue in public health and is a major cause for infant mortality and morbidity. There is a growing consensus that systemic diseases elsewhere in the body may influence PTB. Recent studies have hypothesized that maternal periodontitis could be a high-risk factor for PTB. The aim of the present study was to investigate the relationship between maternal periodontitis on PTB. Materials and Methods: Forty systemically healthy primiparous mothers aged 18–35 years were recruited for the study. Based on inclusion and exclusion criteria, they were categorized into PTB group as cases and full term birth group (FTB as controls. PTB cases (n = 20 defined as spontaneous delivery before/<37 completed weeks of gestation. Controls (FTB were normal births at or after 37 weeks of gestation. Data on periodontal status, pregnancy outcome variables, and information on other factors that may influence adverse pregnancy outcomes were collected within 2 days of labor. Data were subjected to Student's t-test and Pearson's correlation coefficient statistical analysis. Results: Statistically significant difference with respect to the gestational period at the time of delivery and birth weight of the infants in (PTB group (<0.001 compared to (FTB group was observed. Overall, there was statistically significant poor periodontal status in the (PTB group compared to (FTB group. The statistical results also showed a positive correlation between gestational age and clinical parameters. Conclusion: An observable relationship was noticed between periodontitis and gestational age, and a positive correlation was found with respect to PTB and periodontitis. Further studies should be designed to establish periodontal disease as an independent risk factor for PTB/preterm low birth weight.

  20. A case-control study on risk of changing food consumption for colorectal cancer.

    Science.gov (United States)

    Zhang, Bing; Li, Xiangping; Nakama, Hidenori; Zhang, Xing; Wei, Ning; Zhang, Xiulan; Zhang, Leshan

    2002-01-01

    To investigate the relative risk factor of food items for colorectal cancer in four time periods through a case-control study in a Chinese rural area. Colorectal cancer patients diagnosed at a county cancer center, Hebei Province, China, and non-cancer outpatients with similar age, sex, and place of residence were selected for cases and controls, respectively. There were 102 (93.6%) colorectal cancer patients and 99 (90.8%) outpatients being the cases and controls, respectively in the present investigation, who agreed to be interviewed about their food intake, during a 20-year period, through a food frequency questionnaire. The risks of intake of different food items and lifestyle for colorectal cancer were compared between cases and controls. During the 20-year period, diets of both cases and controls changed with increase in intake of animal foods and fruits, and alcohol consumption tended to increase. In the food items, milk intake showed a protective effect in both males and females, and the odds ratios were 0.38 (95% CI 0.16-0.90) and 0.28 (95% CI 0.10-0.81) for males and females, respectively. A reduced risk of fruit intake could be seen in males, while a reduced risk of vegetables could be observed in females. Meat intake and saturated fats were the prominent risk factors for colorectal cancer in males and females, respectively. A comparison of life habits, showed that tea drinking had a consistent protective effect in females, and the odds ratios were 0.21 (0.08-0.58), 0.23 (0.08-0.67), 0.25 (0.10-0.64), and 0.11 (0.04-0.30) for periods of 20-, 10-, 5-years ago, and current time, respectively. These findings indicate that change in food consumption is strongly associated with a change in risk of colorectal cancer, and dietary meat has increased the risk of colorectal cancer. Increase in the consumption of milk and fruits may be a significant measure for colorectal cancer prevention in low-incidence areas.

  1. [Gout not induced by diuretics in a case-control study in general practice

    NARCIS (Netherlands)

    Janssens, H.; Lisdonk, E.H. van de; Janssen, M.; Hoogen, H.J.M. van den; Verbeek, A.L.M.

    2007-01-01

    OBJECTIVE: To determine the relation between diuretics and the development of gout, taking into account the possible confounding by hypertension and cardiovascular diseases. DESIGN: Case-control study. METHOD: With the aid of the data on morbidity and medication from the electronic medical files ofa

  2. Medical risk factors associated with cholangiocarcinoma in Taiwan: a population-based case-control study.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Chang

    Full Text Available BACKGROUND: Cholangiocarcinoma, including intra- and extrahepatic cholangiocarcinoma, is a rare but highly lethal cancer. Despite effort in finding the risk factors of cholangiocarcinoma, the causes of most cholangiocarcinoma remain unknown. This study utilized a population-based case-control design using data from the National Health Insurance Research Database (NHIRD of Taiwan to assess the medical conditions associated with cholangiocarcinoma. METHODS: 5,157 incident cases of cholangiocarcinoma diagnosed during 2004 to 2008 and 20,628 controls matched to the cases on sex, age, and time of diagnosis (reference date for the controls were identified from the NHIRD. Medical risk factors were ascertained from the NHIRD for each individual. Conditional logistic regression was performed to evaluate the association between cholangiocarcinoma and each medical risk factor. RESULTS: The results showed that factors associated with an increased risk of cholangiocarcinoma included cholangitis, cholelithiasis, cholecystitis, cirrhosis of liver, alcoholic liver disease, chronic non-alcoholic liver disease, hepatitis B, hepatitis C, diabetes, chronic pancreatitis, inflammatory bowel disease, and peptic ulcer. In addition, sex and age differences were observed. CONCLUSIONS: This study confirms the association between cholangiocarcinoma and several less established risk factors, including diabetes, inflammatory bowel disease, hepatitis B, hepatitis C, and peptic ulcer (proxy for the presence of Helicobacter Pylori. Future studies should focus on finding additional environmental and genetic causes of cholangiocarcinoma.

  3. Coffee, caffeine-related genes, and Parkinson's disease: a case-control study.

    Science.gov (United States)

    Facheris, Maurizio F; Schneider, Nicole K; Lesnick, Timothy G; de Andrade, Mariza; Cunningham, Julie M; Rocca, Walter A; Maraganore, Demetrius M

    2008-10-30

    An inverse association between coffee and Parkinson's disease (PD) has been reported. However, it remains uncertain why some but not all coffee drinkers are less susceptible to PD. We considered the possibility of a pharmacogenetic effect. In our study, we included 1,208 subjects (446 case-unaffected sibling pairs and 158 case-unrelated control pairs) recruited from an ongoing study of the molecular epidemiology of PD in the Upper Midwest (USA). We collected information on lifetime coffee drinking and we studied two genes: ADORA2A, which encodes the major receptor activity of caffeine in the brain (variants rs5751876 and rs3032740), and CYP1A2, which encodes the major rate-limiting step of caffeine metabolism (variants rs35694136 and rs762551). We did not observe significant associations of coffee drinking or of the genetic variants with PD susceptibility, either independently or jointly, in the sample overall and in most strata. Our study neither supports the hypothesis that coffee protects against PD nor provides evidence for a pharmacogenetic effect. (c) 2008 Movement Disorder Society.

  4. Intrauterine exposure to carbamazepine and specific congenital malformations : systematic review and case-control study

    NARCIS (Netherlands)

    Jentink, Janneke; Dolk, Helen; Loane, Maria A.; Morris, Joan K.; Wellesley, Diana; Garne, Ester; de Jong-van den Berg, Lolkje

    2010-01-01

    Objective To identify specific major congenital malformations associated with use of carbamazepine in the first trimester of pregnancy. Design A review of all published cohort studies to identify key indications and a population based case-control study to test these indications. Setting Review of

  5. Evaluating correlation between serum liver enzymes and toxocariasis: a case control study

    Directory of Open Access Journals (Sweden)

    Hosein Miladi

    2016-06-01

    Full Text Available Objective: To evaluate the prevalence of toxocariasis in individuals with the normal and abnormal level of liver enzymes. Methods: In this case-control study, the serum samples were collected in the individuals referred to diagnostic laboratories of Arak in Iran. A total of 144 sera with abnormal level of liver enzymes were selected as cases and the same numbers of sera with the normal level of liver enzymes also were selected as controls. The sera were examined for anti-Toxocara IgG. Results: Twelve (4.2% sera contained anti-Toxocara antibody and all of them were in the case group. Although the mean of all liver enzymes was significantly different in the two groups (P < 0.05, statistical test showed no relationship between the level of liver enzymes and toxocariasis. Conclusions: It was concluded that the liver enzyme alteration is not the valid indicator for predicting toxocariasis. Because the kind of liver dysfunction, that is caused by the larvae of Toxocara, is unspecified, and it seems factors such as the number of larvae can play a basic role for the emergence of alterations.

  6. High Seroprevalence of Leptospira Exposure in Meat Workers in Northern Mexico: A Case-Control Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Saenz-Soto, Leandro; Martinez-Ramirez, Lucio

    2016-01-01

    Background The seroepidemiology of Leptospira infection in workers occupationally exposed to raw meat has been poorly studied. This work aimed to determine the association between Leptospira exposure and the occupation of meat worker, and to determine the seroprevalence association with socio-demographic, work, clinical and behavioral characteristics of the meat workers studied. Methods We performed a case-control study in 124 meat workers and 124 age- and gender-matched control subjects in Durango City, Mexico. Sera of cases and controls were analyzed for anti-Leptospira IgG antibodies using a commercially available enzyme immunoassay. Data of meat workers were obtained with the aid of a questionnaire. The association of Leptospira exposure with the characteristics of meat workers was analyzed by bivariate and multivariate analyses. Results Anti-Leptospira IgG antibodies were found in 22 (17.7%) of 124 meat workers and in eight (6.5%) of 124 controls (OR = 3.12; 95% CI: 1.33 - 7.33; P = 0.006). Seroprevalence of Leptospira infection was similar between male butchers (17.6%) and female butchers (18.2%) (P = 1.00). Multivariate analysis of socio-demographic, work and behavioral variables showed that Leptospira exposure was associated with duration in the activity, rural residence, and consumption of snake meat and unwashed raw fruits. Conclusions This is the first case-control study of the association of Leptospira exposure with the occupation of meat worker. Results indicate that meat workers represent a risk group for Leptospira exposure. Risk factors for Leptospira exposure found in this study may help in the design of optimal preventive measures against Leptospira infection. PMID:26858797

  7. Pain perception in major depressive disorder: a neurophysiological case-control study.

    Science.gov (United States)

    Zambito Marsala, Sandro; Pistacchi, Michele; Tocco, Pierluigi; Gioulis, Manuela; Fabris, Federico; Brigo, Francesco; Tinazzi, Michele

    2015-10-15

    Depression and pain may sometimes be related conditions. Occasionally, depression may be associated with physical symptoms, such as back pain and headache. Moreover, depression may impair the subjective response to pain and is likely to influence the pain feeling. Conversely, chronic pain may represent an emotional condition as well as physical sensation, and can influence both the mood and behaviour. To better understand the relationship between pain and depression, we therefore assessed the pain threshold and the tolerance pain threshold in patients with depressive disorders. We conducted a case-control study and selected patients who had recently received a diagnosis of major depression (DSM-IV), before treatment, and without any significant pain complaints. Age- and sex-matched healthy controls were also included. Tactile and pain thresholds were assessed in all subjects through an electrical stimulation test. All results were compared between the groups. 27 patients and 27 age-matched healthy controls were included in the study. Tactile, pain and tolerance thresholds were evaluated in all subjects. The pain threshold and pain tolerance were lower in patients with major depression than controls. All differences were statistically significant (pdepressive disorders. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Colon cancer risk and different HRT formulations: a case-control study

    Directory of Open Access Journals (Sweden)

    Thai Do

    2007-05-01

    Full Text Available Abstract Background Most studies have found no increased risk of colon cancer associated with hormone replacement therapy (HRT, or even a decreased risk. But information about the effects of different HRT preparations is lacking. Methods A case-control study was performed within Germany in collaboration with regional cancer registries and tumor centers. Up to 5 controls were matched to each case of colon cancer. Conditional logistic regression analysis was applied to estimate crude and adjusted odds ratios (OR and 95% confidence intervals (95% CI. Stratified analyses were performed to get an impression of the risk associated with different estrogens and progestins. Results A total of 354 cases of colon cancer were compared with 1422 matched controls. The adjusted overall risk estimate for colon cancer (ColC associated with ever-use of HRT was 0.97 (0.71 – 1.32. No clinically relevant trends for ColC risk were observed with increasing duration of HRT use, or increasing time since first or last HRT use in aggregate. Whereas the overall risk estimates were stable, the numbers in many of the sub-analyses of HRT preparation groups (estrogens and progestins were too small for conclusions. Nevertheless, if the ColC risk estimates are taken at face value, most seemed to be reduced compared with never-use of HRT, but did not vary much across HRT formulation subgroups. In particular, no substantial difference in ColC risk was observed between HRT-containing conjugated equine estrogens (CEE or medroxyprogesterone acetate (MPA and other formulations more common in Europe. Conclusion Ever-use of HRT was not associated with an increased risk of colon cancer. In contrary, most risk estimates pointed non-significantly toward a lower ColC risk in HRT ever user. They did not vary markedly among different HRT formulations (estrogens, progestins. However, the small numbers and the overlapping nature of the subgroups suggest cautious interpretation.

  9. Family clustering of secondary chronic kidney disease with hypertension or diabetes mellitus. A case-control study.

    Science.gov (United States)

    de Almeida, Fernando Antonio; Ciambelli, Giuliano Serafino; Bertoco, André Luz; Jurado, Marcelo Mai; Siqueira, Guilherme Vasconcelos; Bernardo, Eder Augusto; Pavan, Maria Valeria; Gianini, Reinaldo José

    2015-02-01

    In Brazil hypertension and type 2 diabetes mellitus are responsible for 60% of cases of end-stage renal disease in renal replacement therapy. In the United States studies have identified family clustering of chronic kidney disease, predominantly in African-Americans. A single Brazilian study observed family clustering among patients with chronic kidney disease when compared with hospitalized patients with normal renal function. This article aims to assess whether there is family clustering of chronic kidney disease in relatives of individuals in renal replacement therapy caused by hypertension and/or diabetes mellitus. A case-control study with 336 patients in renal replacement therapy with diabetes mellitus or hypertension for at least 5 years (cases) and a control matched sample group of individuals with hypertension or diabetes mellitus and normal renal function (n = 389). Individuals in renal replacement therapy (cases) had a ratio of 2.35 (95% CI 1.42-3.89, p hypertension or diabetes mellitus).

  10. Caries Experience in Children with and without Molar-Incisor Hypomineralisation: A Case-Control Study.

    Science.gov (United States)

    Grossi, Juliana de Aguiar; Cabral, Renata Nunes; Leal, Soraya Coelho

    2017-01-01

    The aim of this study was to compare the caries experience of children with and without molar-incisor hypomineralisation (MIH). A case-control study was designed in which 130 children aged between 7 and 13 years with MIH (cases) were matched with 130 children without the condition (controls) according to age, sex, and school. Dental caries and MIH were assessed using the Caries Assessment Spectrum and Treatment (CAST) and European Academy of Paediatric Dentistry (EAPD) criteria, respectively, by three examiners. CAST was converted into DMFT/dmft; the Kruskal-Wallis test was performed to analyse whether dmft/DMFT was influenced by the severity of MIH. Associations between MIH and dental caries were analysed at child and tooth levels: between and within subjects, respectively. To correlate MIH severity and the occurrence of dental caries, the Cochran-Armitage test was used. The mean age of the children was 9.63 ± 1.29 years. The mean dmft for cases was 1.23 ± 1.99 and for controls 1.71 ± 2.22 (p > 0.05). For the DMFT, the mean scores for cases and controls were 0.45 ± 0.90 and 0.07 ± 0.25, respectively (p MIH than in those without the condition. The same pattern was seen for the within-subject analysis. It was observed that the increase in MIH severity resulted in more teeth being affected by dentine carious lesions (p = 0.0003). Children with MIH presented a higher experience of caries in the permanent dentition than those without the condition. MIH was considered a risk factor for caries development. © 2017 S. Karger AG, Basel.

  11. Healthcare Associated Infections of Methicillin-Resistant Staphylococcus aureus: A Case-Control-Control Study.

    Directory of Open Access Journals (Sweden)

    Zhenjiang Yao

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA is one of the most widespread and dangerous pathogens in healthcare settings. We carried out this case-control-control study at a tertiary care hospital in Guangzhou, China, to examine the antimicrobial susceptibility patterns, risk factors and clinical outcomes of MRSA infections.A total of 57 MRSA patients, 116 methicillin-susceptible Staphylococcus aureus (MSSA patients and 102 S. aureus negative patients were included in this study. We applied the disk diffusion method to compare the antimicrobial susceptibilities of 18 antibiotics between MRSA and MSSA isolates. Risk factors of MRSA infections were evaluated using univariate and multivariate logistic regression models. We used Cox proportional hazards models and logistic regression analysis to assess the hospital stay duration and fatality for patients with MRSA infections.The MRSA group had significantly higher resistance rates for most drugs tested compared with the MSSA group. Using MSSA patients as controls, the following independent risk factors of MRSA infections were identified: 3 or more prior hospitalizations (OR 2.8, 95% CI 1.3-5.8, P = 0.007, chronic obstructive pulmonary disease (OR 5.9, 95% CI 1.7-20.7, P = 0.006, and use of a respirator (OR 3.6, 95% CI 1.0-12.9, P = 0.046. With the S. aureus negative patients as controls, use of a respirator (OR 3.8, 95% CI 1.0-13.9, P = 0.047 and tracheal intubation (OR 8.2, 95% CI 1.5-45.1, P = 0.016 were significant risk factors for MRSA infections. MRSA patients had a longer hospital stay duration and higher fatality in comparison with those in the two control groups.MRSA infections substantially increase hospital stay duration and fatality. Thus, MRSA infections are serious issues in this healthcare setting and should receive more attention from clinicians.

  12. Case-control study of lung cancer among workers at a uranium processing plant

    International Nuclear Information System (INIS)

    Cookfair, D.L.

    1982-01-01

    The purpose of this case-control study was to investigate the relationship between exposure to radiation resulting from the inhalation of uranium dust and the dust of uranium-bearing compounds and death due to lung cancer. Cases and controls were chosen from a cohort of white male workers employed at one uranium processing plant during World War II. The 330 cases consisted of all lung cancer deaths occurring in the cohort between 1943 and 1973. Level of exposure to radiation and other potential workplace carcinogens was determined for each worker using process manuals, industrial hygiene reports, air monitoring data and individual work histories. Smoking status and information regarding medical variables was determined from employee medical records. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Data were analyzed using Mantel-Haenszel stratified analysis and logistic regression. Relative risk was found to increase with increasing level of lung dose exposure even after controlling for age, smoking status and other workplace exposures, but only for those who were over the age of 44 when first exposed. A statistically significant excess in risk was found for men in this hire age group with a cumulative lung dose of 20 rads or more. The risk associated with the overall work environment was also investigated using a summary measure of total workplace exposure called chemical rank. A similar relationship existed between chemical rank and lung cancer to that found for cumulative lung dose and lung cancer

  13. Impact of Drinking Water Fluoride on Human Thyroid Hormones: A Case- Control Study.

    Science.gov (United States)

    Kheradpisheh, Zohreh; Mirzaei, Masoud; Mahvi, Amir Hossein; Mokhtari, Mehdi; Azizi, Reyhane; Fallahzadeh, Hossein; Ehrampoush, Mohammad Hassan

    2018-02-08

    The elevated fluoride from drinking water impacts on T 3 , T 4 and TSH hormones. The aim was study impacts of drinking water fluoride on T 3 , T 4 and TSH hormones inYGA (Yazd Greater Area). In this case- control study 198 cases and 213 controls were selected. Fluoride was determined by the SPADNS Colorimetric Method. T 3 , T 4 and TSH hormones tested in the Yazd central laboratory by RIA (Radio Immuno Assay) method. The average amount of TSH and T 3 hormones based on the levels of fluoride in two concentration levels 0-0.29 and 0.3-0.5 (mg/L) was statistically significant (P = 0.001 for controls and P = 0.001 for cases). In multivariate regression logistic analysis, independent variable associated with Hypothyroidism were: gender (odds ratio: 2.5, CI 95%: 1.6-3.9), family history of thyroid disease (odds ratio: 2.7, CI 95%: 1.6-4.6), exercise (odds ratio: 5.34, CI 95%: 3.2-9), Diabetes (odds ratio: 3.7, CI 95%: 1.7-8), Hypertension (odds ratio: 3.2, CI 95%: 1.3-8.2), water consumption (odds ratio: 4, CI 95%: 1.2-14). It was found that fluoride has impacts on TSH, T 3 hormones even in the standard concentration of less than 0.5 mg/L. Application of standard household water purification devices was recommended for hypothyroidism.

  14. Power for genetic association study of human longevity using the case-control design

    DEFF Research Database (Denmark)

    Tan, Qihua; Zhao, Jing Hua; Zhang, Dongfeng

    2008-01-01

    The efficiency of the popular case-control design in gene-longevity association studies needs to be verified because, different from a binary trait, longevity represents only the extreme end of the continuous life span distribution without a clear cutoff for defining the phenotype. In this paper...

  15. Oral Streptococcal Endocarditis, Oral Hygiene Habits, and Recent Dental Procedures: A Case-Control Study.

    Science.gov (United States)

    Duval, Xavier; Millot, Sarah; Chirouze, Catherine; Selton-Suty, Christine; Moby, Vanessa; Tattevin, Pierre; Strady, Christophe; Euvrard, Edouard; Agrinier, Nelly; Thomas, Daniel; Hoen, Bruno; Alla, François

    2017-06-15

    We aimed to compare oral hygiene habits, orodental status, and dental procedures in patients with infective endocarditis (IE) according to whether the IE-causing microorganism originated in the oral cavity. We conducted an assessor-blinded case-control study in 6 French tertiary-care hospitals. Oral hygiene habits were recorded using a self-administered questionnaire. Orodental status was analyzed by trained dental practitioners blinded to the microorganism, using standardized clinical examination and dental panoramic tomography. History of dental procedures was obtained through patient and dentist interviews. Microorganisms were categorized as oral streptococci or nonoral pathogens using an expert-validated list kept confidential during the course of the study. Cases and controls had definite IE caused either by oral streptococci or nonoral pathogens, respectively. Participants were enrolled between May 2008 and January 2013. Cases (n = 73) were more likely than controls (n = 192) to be aged calculus, and infectious dental diseases did not significantly differ between groups. Patients with IE caused by oral streptococci differ from patients with IE caused by nonoral pathogens regarding background characteristics, oral hygiene habits, and recent dental procedures, but not current orodental status. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com

  16. Residential radon exposure and lung cancer risk in Misasa, Japan. A case-control study

    International Nuclear Information System (INIS)

    Sobue, Tomotaka; Lee, Valerie S.; Ye, Weimin; Tanooka, Hiroshi; Mifune, Masaaki; Suyama, Akihiko; Koga, Taeko; Morishima, Hiroshige; Kondo, Sohei

    2000-01-01

    In order to investigate an association between residential radon exposure and risk of lung cancer, a case-control study was conducted in Misasa Town, Tottori Prefecture, Japan. The case series consisted of 28 people who had died of lung cancer in the years 1976-96 and 36 controls chosen randomly from the residents in 1976, matched by sex and year of birth. Individual residential radon concentrations were measured for 1 year with alpha track detectors. The average radon concentration was 46 Bq/m 3 for cases and 51 Bq/m 3 for controls. Compared to the level of 24 or less Bq/m 3 , the adjusted odds ratios of lung cancer associated with radon levels of 25-49, 50-99 and 100 or more Bq/m 3 , were 1.13 (95% confidence interval; 0.29-4.40), 1.23 (0.16-9.39) and 0.25 (0.03-2.33), respectively. None of the estimates showed statistical significance, due to small sample size. When the subjects were limited to only include residents of more than 30 years, the estimates did not change substantially. This study did not find that the risk pattern of lung cancer, possibly associated with residential radon exposure, in Misasa Town differed from patterns observed in other countries. (author)

  17. Evaluation of salivary tumor necrosis factor-alpha in patients with the chronic periodontitis: A case-control study.

    Science.gov (United States)

    Yousefimanesh, Hojatollah; Maryam, Robati; Mahmoud, Jahangirnezhad; Mehri, Ghafourian Boroujerdnia; Mohsen, Taghipour

    2013-11-01

    Periodontitis is a chronic infectious disease that leads to inflammation of the tissues supporting the teeth, bone loss, attachment loss progressively. In chronic periodontitis for starting the host response and inflammatory reaction, the presence of the infectious agent is necessary. One of inflammatory factors is tumor necrosis factor-alpha (TNF-α) that appear to be important in the destruction of periodontal tissues that were examined in this study. This study was performed in the laboratory and case-control study. The samples of study collected from 30 individuals with chronic periodontitis and 30 healthy controls that matched for age and sex, together. Unstimulated saliva samples were collected from patients and then TNF-α level were measured by enzyme-linked immunosorbent assay and were compared with the control group. In this study for statistical analysis, Mann-Whitney was used. There were differences in mean salivary concentrations of TNF-α in controls and patients. The average concentration in the case group was 9.1 (pg/ml) and the control group was 8.7 (pg/ml), but there was no significant difference between case and control groups (P > 0.05). The results of this analysis showed no significant relationship between two groups TNF-α concentration. This biomarker can not seem to be a good index to evaluate or predict periodontal disease.

  18. Evaluation of salivary tumor necrosis factor-alpha in patients with the chronic periodontitis: A case-control study

    Directory of Open Access Journals (Sweden)

    Hojatollah Yousefimanesh

    2013-01-01

    Full Text Available Context: Periodontitis is a chronic infectious disease that leads to inflammation of the tissues supporting the teeth, bone loss, attachment loss progressively. In chronic periodontitis for starting the host response and inflammatory reaction, the presence of the infectious agent is necessary. Aims: One of inflammatory factors is tumor necrosis factor-alpha (TNF-α that appear to be important in the destruction of periodontal tissues that were examined in this study. Materials and Methods: This study was performed in the laboratory and case-control study. The samples of study collected from 30 individuals with chronic periodontitis and 30 healthy controls that matched for age and sex, together. Unstimulated saliva samples were collected from patients and then TNF-α level were measured by enzyme-linked immunosorbent assay and were compared with the control group. Statistical Analysis Used: In this study for statistical analysis, Mann-Whitney was used. Results: There were differences in mean salivary concentrations of TNF-α in controls and patients. The average concentration in the case group was 9.1 (pg/ml and the control group was 8.7 (pg/ml, but there was no significant difference between case and control groups (P > 0.05. Conclusions: The results of this analysis showed no significant relationship between two groups TNF-α concentration.This biomarker can not seem to be a good index to evaluate or predict periodontal disease.

  19. Immuno-related polymorphisms and cervical cancer risk: The IARC multicentric case-control study.

    Directory of Open Access Journals (Sweden)

    James McKay

    Full Text Available A small proportion of women who are exposed to infection with human-papillomavirus (HPV develop cervical cancer (CC. Genetic factors may affect the risk of progression from HPV infection to cervical precancer and cancer. We used samples from the International Agency for Research on Cancer (IARC multicentric case-control study to evaluate the association of selected genetic variants with CC. Overall, 790 CC cases and 717 controls from Algeria, Morocco, India and Thailand were included. Cervical exfoliated cells were obtained from control women and cervical exfoliated cells or biopsy specimens from cases. HPV-positivity was determined using a general primer GP5+/6+ mediated PCR. Unconditional logistic regression was used to estimate odds ratios (OR and corresponding 95% confidence intervals (CI of host genotypes with CC risk, using the homozygous wild type genotype as the referent category and adjusting by age and study centre. The association of polymorphisms with the risk of high-risk HPV-positivity among controls was also evaluated. A statistically significant association was observed between single nucleotide polymorphism (SNP CHR6 rs2844511 and CC risk: the OR for carriers of the GA or GG genotypes was 0.70 (95% CI: 0.43-1.14 and 0.61 (95% CI: 0.38-0.98, respectively, relative to carriers of AA genotype (p-value for trend 0.03. We also observed associations of borderline significance with the TIPARP rs2665390 polymorphism, which was previously found to be associated with ovarian and breast cancer, and with the EXOC1 rs13117307 polymorphism, which has been linked to cervical cancer in a large study in a Chinese population. We confirmed the association between CC and the rs2844511 polymorphism previously identified in a GWAS study in a Swedish population. The major histocompatibility region of chromosome 6, or perhaps other SNPs in linkage disequilibrium, may be involved in CC onset.

  20. Lack of Association Between Toxoplasma gondii Infection and Diabetes Mellitus: A Matched Case-Control Study in a Mexican Population.

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Loera-Moncivais, Nayely; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Hernandez-Madrid, Guillermina; Rabago-Sanchez, Elizabeth; Centeno-Tinoco, Maria Magdalena; Sandoval-Carrillo, Ada A; Salas-Pacheco, Jose M; Campos-Moreno, Oscar Vladimir; Antuna-Salcido, Elizabeth Irasema

    2017-06-01

    Very little is known about the association between infection with Toxoplasma gondii ( T. gondii ) and diabetes mellitus. We perform an age- and gender-matched case-control study to determine the association of T. gondii infection and diabetes mellitus. Cases included 156 patients with diabetes mellitus and 156 controls without diabetes mellitus who attended in two public clinics in Durango City, Mexico. Sera of cases and controls were tested for the presence of anti- Toxoplasma IgG and IgM antibodies using commercially available enzyme-linked fluorescence assays (ELFA). Anti- T. gondii IgG antibodies were found in 10 (6.4%) of the 156 cases and in five (3.2%) of the 156 controls (odds ratio (OR): 2.06; 95% confidence interval (CI): 0.69 - 6.19; P = 0.18). The frequency of high (> 150 IU/mL) anti- T. gondii IgG levels in seropositive cases (1/10: 10.0%) was comparable to the one (1/5: 20%) in seropositive controls (OR: 0.44; 95% CI: 0.02 - 9.03; P = 1.00). None of the 10 cases and five controls with seropositivity to anti- T. gondii IgG antibodies were positive for anti- T. gondii IgM antibodies. Stratification by gender showed similar frequencies of T. gondii infection in female cases (7/107: 6.5%) and female controls (4/107: 3.7%) (OR: 1.80; 95% CI: 0.51 - 6.34; P = 0.53), and in male cases (3/49: 6.1%) and male controls (1/49: 2.0%) (OR: 3.13; 95% CI: 0.31 - 31.19; P = 0.61). We conclude that there is not serological evidence of an association between T. gondii infection and diabetes mellitus in the studied subjects in Durango City, Mexico. Further studies to elucidate the role of T. gondii in diabetes should be conducted.

  1. Association of atrial fibrillation and cancer: Analysis from two large population-based case-control studies.

    Science.gov (United States)

    Saliba, Walid; Rennert, Hedy S; Gronich, Naomi; Gruber, Stephen B; Rennert, Gad

    2018-01-01

    An association between atrial fibrillation (AF) and risk of cancer has been suggested in several studies, including prospective cohort studies. However, the magnitude and the temporal nature of this association remain unclear. Data from two large prospective population-based case-control studies, the Molecular Epidemiology of Colorectal Cancer (MECC, n = 8,383) and the Breast Cancer in Northern Israel Study (BCINIS, n = 11,608), were used to better understand the nature and temporality of a possible association between cancer diagnosis and AF events before and after cancer diagnosis. A case-control study approach was employed to study prior AF as a risk factor for cancer, and a cohort study approach was employed to study incident cancer as a risk factor for AF. AF was associated with a significant reduced odds of cancer as reflected in the case-control approach, with an adjusted OR = 0.77 (95% CI, 0.65-0.91), while cancer was not found to be significantly associated with elevated risk of AF in the cohort approach, with an adjusted HR = 1.10 (0.98-1.23). The immediate period (90 days) after an AF event was associated with a 1.85 times increased risk of cancer, and the immediate period after the diagnosis of cancer was associated with a 3.4 fold increased risk of AF. These findings probably reflect both the effect of acute transient conditions associated with new cancer diagnosis and detection bias. Similar results were identified with colorectal and breast cancer cases. Atrial fibrillation of longer than 90 days duration is associated with reduced odds of new cancer diagnosis. The results of this study suggest that an association observed in prior research may be due to instances related to cancer diagnosis and detection bias rather than a causal relationship. However, there may be bias in the sampling and residual confounding that distort the associations.

  2. Behavioural Comorbidity in Tanzanian Children with Epilepsy: A Community-Based Case-Control Study

    Science.gov (United States)

    Burton, Kathryn; Rogathe, Jane; Hunter, Ewan; Burton, Matthew; Swai, Mark; Todd, Jim; Neville, Brian; Walker, Richard; Newton, Charles

    2011-01-01

    Aim: The aim of this study was to define the prevalence of and risk factors for behavioural disorders in children with epilepsy from a rural district of Tanzania by conducting a community-based case-control study. Method: One hundred and twelve children aged 6 to 14 years (55 males, 57 females; median age 12y) with active epilepsy (at least two…

  3. Attitudes and Perception Towards Eye Donation in Patients with Corneal Disease: A Case-controlled Population-based Study.

    Science.gov (United States)

    Noopur, Gupta; Praveen, Vashist; Radhika, Tandon; Sanjeev K, Gupta; Mani, Kalaivani; Deepak, Kumar

    2018-06-01

    To assess awareness, barriers, and misconceptions related to eye donation in people with corneal disease as compared to controls in a population setting. A population-based study was conducted in 25 randomly selected clusters of Rural Gurgaon, Haryana, India, as part of the CORE (Cornea Opacity Rural Epidemiological) study. In addition to ophthalmic examination, knowledge and perceptions regarding eye donation were assessed through a validated questionnaire. The questionnaire captured the sociodemographic factors influencing awareness regarding eye donation in participants with corneal disease and twice the number of age- and gender-matched controls recruited from the same study clusters. Descriptive statistics were computed along with multivariable logistic regression analysis to determine associated factors for awareness of eye donation. In the CORE study, 452 participants had corneal opacities on ocular examination. Of these, 442 were assessed for eye donation awareness. Additionally, 884 age- and gender-matched controls were recruited. The mean age of cases and controls was 60.9 ± 15.5 and 59.6 ± 14.3 years, respectively. Awareness of eye donation in cases and controls was 46.4% (n = 205 of 442) and 52.3% (n = 462 of 884), respectively (P = 0.044). Educational status was an important factor determining knowledge about eye donation in both cases and controls (P = donated before death or even after 24 h of death and that any type of blindness could be treated with corneal transplantation were prevalent. The study demonstrated that although there is substantial awareness about eye donation, there are numerous barriers in this population that need to be resolved to improve donation rates. Additional efforts are needed to translate this awareness into actual eye donation in both cases with corneal disease and controls.

  4. Etiology of Diarrhea in Young Children in Denmark: a Case-Control Study

    Science.gov (United States)

    Olesen, Bente; Neimann, Jacob; Böttiger, Blenda; Ethelberg, Steen; Schiellerup, Peter; Jensen, Charlotte; Helms, Morten; Scheutz, Flemming; Olsen, Katharina E. P.; Krogfelt, Karen; Petersen, Eskild; Mølbak, Kåre; Gerner-Smidt, Peter

    2005-01-01

    Infectious gastroenteritis is one of the most common diseases in young children. To clarify the infectious etiology of diarrhea in Danish children less than 5 years of age, we conducted a 2-year prospective case-control study. Stools from 424 children with diarrhea and 870 asymptomatic age-matched controls were examined, and their parents were interviewed concerning symptoms. Rotavirus, adenovirus, and astrovirus were detected by enzyme-linked immunosorbent assay, and norovirus and sapovirus were detected by PCR. Salmonella, thermotolerant Campylobacter, Yersinia, Shigella, and Vibrio spp. were detected by standard methods. Shiga toxin-producing (STEC), attaching-and-effacing (A/EEC), enteropathogenic (EPEC), enterotoxigenic, enteroinvasive, and enteroaggregative Escherichia coli were detected by using colony hybridization with virulence gene probes and serotyping. Parasites were detected by microscopy. Overall, a potential pathogen was found in 54% of cases. More cases than controls were infected with rotavirus, Salmonella, norovirus, adenovirus, Campylobacter, sapovirus, STEC, classical EPEC, Yersinia, and Cryptosporidium strains, whereas A/EEC, although common, was not associated with illness. The single most important cause of diarrhea was rotavirus, which points toward the need for a childhood vaccine for this pathogen, but norovirus, adenovirus, and sapovirus were also major etiologies. Salmonella sp. was the most common bacterial pathogen, followed by Campylobacter, STEC, Yersinia, and classical EPEC strains. A/EEC not belonging to the classical EPEC serotypes was not associated with diarrhea, underscoring the importance of serotyping for the definition of EPEC. PMID:16081890

  5. A Case-Control Study of Prenatal Thallium Exposure and Low Birth Weight in China.

    Science.gov (United States)

    Xia, Wei; Du, Xiaofu; Zheng, Tongzhang; Zhang, Bin; Li, Yuanyuan; Bassig, Bryan A; Zhou, Aifen; Wang, Youjie; Xiong, Chao; Li, Zhengkuan; Yao, Yuanxiang; Hu, Jie; Zhou, Yanqiu; Liu, Juan; Xue, Weiyan; Ma, Yue; Pan, Xinyun; Peng, Yang; Xu, Shunqing

    2016-01-01

    Thallium (Tl) is a highly toxic heavy metal widely present in the environment. Case reports have suggested that maternal exposure to high levels of Tl during pregnancy is associated with low birth weight (LBW), but epidemiological data are limited. This study was designed to evaluate whether prenatal Tl exposure is associated with an increased risk of LBW. This case-control study involving 816 study participants (204 LBW cases and 612 matched controls) was conducted in Hubei Province, China, in 2012-2014. Tl concentrations were measured in maternal urine collected at delivery, and associations with LBW were evaluated using conditional logistic regression. Higher maternal urinary Tl levels were significantly associated with increased risk of LBW [crude odds ratio (OR) = 1.52; 95% CI: 1.00, 2.30 for the highest vs. lowest tertile], and the association was similarly elevated after adjustment for potential confounders (adjusted OR = 1.90; 95% CI: 1.01, 3.58 for the highest vs. lowest tertile). Stratified analyses showed slightly higher risk estimates for LBW associated with higher Tl levels for mothers thallium exposure and low birth weight in China. Environ Health Perspect 124:164-169; http://dx.doi.org/10.1289/ehp.1409202.

  6. Studies of CTNNBL1 and FDFT1 variants and measures of obesity: analyses of quantitative traits and case-control studies in 18,014 Danes

    DEFF Research Database (Denmark)

    Andreasen, Camilla Helene; Mogensen, Mette Sloth; Borch-Johnsen, Knut

    2009-01-01

    of obesity-related quantitative traits, and case-control studies in large study samples of Danes. METHODS: The FDFT1 rs7001819, CTNNBL1 rs6013029 and rs6020846 were genotyped, using TaqMan allelic discrimination, in a combined study sample comprising 18,014 participants ascertained from; the population...... and a previous study. FDFT1 rs7001819 showed no association with obesity, neither when analysing quantitative traits nor when performing case-control studies of obesity.......). The most significantly associating variants within CTNNBL1 including rs6013029 and rs6020846 were additionally confirmed to associate with morbid obesity in a French Caucasian case-control sample. The aim of this study was to investigate the impact of these three variants on obesity, through analyses...

  7. Case-control study of congenital malformations and occupational exposure to low-level ionizing radiation

    International Nuclear Information System (INIS)

    Sever, L.E.; Gilbert, E.S.; Hessol, N.A.; McIntyre, J.M.

    1988-01-01

    In a case-control study, the authors investigated the association of parental occupational exposure to low-level external whole-body penetrating ionizing radiation and risk of congenital malformations in their offspring. Cases and controls were ascertained from births in two counties in southeastern Washington State, where the Hanford Site has been a major employer. A unique feature of this study was the linking of quantitative individual measurement of external whole-body penetrating ionizing radiation exposure of employees at the Hanford Site, using personal dosimeters, and the disease outcome, congenital malformations. The study population included 672 malformation cases and 977 matched controls from births occurring from 1957 through 1980. Twelve specific malformation types were analyzed for evidence of association with employment of the parents at Hanford and with occupational exposure to ionizing radiation. Two defects, congenital dislocation of the hip and tracheoesophageal fistula, showed statistically significant associations with employment of the parents at Hanford, but not with parental radiation exposure. Neural tube defects showed a significant association with parental preconception exposure, on the basis of a small number of cases. Eleven other defects, including Down syndrome, for which an association with radiation was considered most likely, showed no evidence of such an association. When all malformations were analyzed as a group, there was no evidence of an association with employment of the parents at Hanford, but the relation of parental exposure to radiation before conception was in the positive direction (one-tailed p value between 0.05 and 0.10). Given the number of statistical tests conducted, some or all of the observed positive correlations are likely to represent false positive findings. 30 references

  8. Colorectal cancer and its association with the metabolic syndrome: a Malaysian multi-centric case-control study.

    Science.gov (United States)

    Ulaganathan, V; Kandiah, M; Zalilah, M S; Faizal, J A; Fijeraid, H; Normayah, K; Gooi, B H; Othman, R

    2012-01-01

    Colorectal cancer (CRC) and the metabolic syndrome (MetS) are both on the rise in Malaysia. A multi-centric case-control study was conducted from December 2009 to January 2011 to determine any relationship between the two. Patients with confirmed CRC based on colonoscopy findings and cancer free controls from five local hospitals were assessed for MetS according to the International Diabetes Federation (IDF) definition. Each index case was matched for age, gender and ethnicity with two controls (140: 280). MetS among cases was highly prevalent (70.7%), especially among women (68.7%). MetS as an entity increased CRC risk by almost three fold independently (OR=2.61, 95%CI=1.53-4.47). In men MetS increased the risk of CRC by two fold (OR=2.01, 95%CI, 1.43-4.56), demonstrating an increasing trend in risk with the number of Mets components observed. This study provides evidence for a positive association between the metabolic syndrome and colorectal cancer. A prospective study on the Malaysian population is a high priority to confirm these findings.

  9. Individual socioeconomic status and breast cancer diagnostic stages: a French case-control study.

    Science.gov (United States)

    Orsini, Mattea; Trétarre, Brigitte; Daurès, Jean-Pierre; Bessaoud, Faiza

    2016-06-01

    Health inequalities have increased over the last 30 years. Our goal was to investigate the relationship between low individual socioeconomic status and poor breast cancer prognosis. Our hypothesis was: low socioeconomic status patients have a higher risk of being diagnosed with late stage breast cancer than high socioeconomic status ones due to delayed diagnosis. We conducted a matched case-control study on 619 women with breast cancer, living in the Hérault, a French administrative area. Both Cases and Controls were recruited among invasive cases diagnosed in 2011 and 2012 and treated in Hérault care centers. Cases were defined as patients with advanced stages. Controls were composed of early stage patients. Individual socioeconomic status was assessed using a validated individual score adapted to the French population and health care system. We observed that low socioeconomic status patients have a 2-fold risk of having late stage breast cancer regardless of cancer characteristics and detection mode (screening vs. clinical signs). One reason explaining those results could be that low socioeconomic status patients have less regular follow-up which can lead to later and poorer diagnosis. Follow-up is improved for women with a better awareness of breast cancer. Health policy makers could reduce health inequalities by reducing the delay in breast cancer diagnosis for low socioeconomic status women. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  10. Severe Sepsis in Severely Malnourished Young Bangladeshi Children with Pneumonia: A Retrospective Case Control Study.

    Directory of Open Access Journals (Sweden)

    Mohammod Jobayer Chisti

    Full Text Available In developing countries, there is no published report on predicting factors of severe sepsis in severely acute malnourished (SAM children having pneumonia and impact of fluid resuscitation in such children. Thus, we aimed to identify predicting factors for severe sepsis and assess the outcome of fluid resuscitation of such children.In this retrospective case-control study SAM children aged 0-59 months, admitted to the Intensive Care Unit (ICU of the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh from April 2011 through July 2012 with history of cough or difficult breathing and radiologic pneumonia, who were assessed for severe sepsis at admission constituted the study population. We compared the pneumonic SAM children with severe sepsis (cases = 50 with those without severe sepsis (controls = 354. Severe sepsis was defined with objective clinical criteria and managed with fluid resuscitation, in addition to antibiotic and other supportive therapy, following the standard hospital guideline, which is very similar to the WHO guideline.The case-fatality-rate was significantly higher among the cases than the controls (40% vs. 4%; p<0.001. In logistic regression analysis after adjusting for potential confounders, lack of BCG vaccination, drowsiness, abdominal distension, acute kidney injury, and metabolic acidosis at admission remained as independent predicting factors for severe sepsis in pneumonic SAM children (p<0.05 for all comparisons.We noted a much higher case fatality among under-five SAM children with pneumonia and severe sepsis who required fluid resuscitation in addition to standard antibiotic and other supportive therapy compared to those without severe sepsis. Independent risk factors and outcome of the management of severe sepsis in our study children highlight the importance for defining optimal fluid resuscitation therapy aiming at reducing the case fatality in such children.

  11. Case-control study of candidate gene methylation and adenomatous polyp formation.

    Science.gov (United States)

    Alexander, M; Burch, J B; Steck, S E; Chen, C-F; Hurley, T G; Cavicchia, P; Shivappa, N; Guess, J; Zhang, H; Youngstedt, S D; Creek, K E; Lloyd, S; Jones, K; Hébert, J R

    2017-02-01

    Colorectal cancer (CRC) is one of the most common and preventable forms of cancer but remains the second leading cause of cancer-related death. Colorectal adenomas are precursor lesions that develop in 70-90 % of CRC cases. Identification of peripheral biomarkers for adenomas would help to enhance screening efforts. This exploratory study examined the methylation status of 20 candidate markers in peripheral blood leukocytes and their association with adenoma formation. Patients recruited from a local endoscopy clinic provided informed consent and completed an interview to ascertain demographic, lifestyle, and adenoma risk factors. Cases were individuals with a histopathologically confirmed adenoma, and controls included patients with a normal colonoscopy or those with histopathological findings not requiring heightened surveillance (normal biopsy, hyperplastic polyp). Methylation-specific polymerase chain reaction was used to characterize candidate gene promoter methylation. Odds ratios (ORs) and 95 % confidence intervals (95% CIs) were calculated using unconditional multivariable logistic regression to test the hypothesis that candidate gene methylation differed between cases and controls, after adjustment for confounders. Complete data were available for 107 participants; 36 % had adenomas (men 40 %, women 31 %). Hypomethylation of the MINT1 locus (OR 5.3, 95% CI 1.0-28.2) and the PER1 (OR 2.9, 95% CI 1.1-7.7) and PER3 (OR 11.6, 95% CI 1.6-78.5) clock gene promoters was more common among adenoma cases. While specificity was moderate to high for the three markers (71-97 %), sensitivity was relatively low (18-45 %). Follow-up of these epigenetic markers is suggested to further evaluate their utility for adenoma screening or surveillance.

  12. Outbreak of acute renal failure in Panama in 2006: a case-control study.

    Science.gov (United States)

    Rentz, E Danielle; Lewis, Lauren; Mujica, Oscar J; Barr, Dana B; Schier, Joshua G; Weerasekera, Gayanga; Kuklenyik, Peter; McGeehin, Michael; Osterloh, John; Wamsley, Jacob; Lum, Washington; Alleyne, Camilo; Sosa, Nestor; Motta, Jorge; Rubin, Carol

    2008-10-01

    In September 2006, a Panamanian physician reported an unusual number of patients with unexplained acute renal failure frequently accompanied by severe neurological dysfunction. Twelve (57%) of 21 patients had died of the illness. This paper describes the investigation into the cause of the illness and the source of the outbreak. Case-control and laboratory investigations were implemented. Case patients (with acute renal failure of unknown etiology and serum creatinine > 2 mg/dl) were individually matched to hospitalized controls for age (+/- 5 years), sex and admission date (< 2 days before the case patient). Questionnaire and biological data were collected. The main outcome measure was the odds of ingesting prescription cough syrup in cases and controls. Forty-two case patients and 140 control patients participated. The median age of cases was 68 years (range: 25-91 years); 64% were male. After controlling for pre-existing hypertension and renal disease and the use of angiotensin-converting enzyme inhibitors, a significant association was found between ingestion of prescription cough syrup and illness onset (adjusted odds ratio: 31.0, 95% confidence interval: 6.93-138). Laboratory analyses confirmed the presence of diethylene glycol (DEG) in biological samples from case patients, 8% DEG contamination in cough syrup samples and 22% contamination in the glycerin used to prepare the cough syrup. The source of the outbreak was DEG-contaminated cough syrup. This investigation led to the recall of approximately 60 000 bottles of contaminated cough syrup, widespread screening of potentially exposed consumers and treatment of over 100 affected patients.

  13. Cancer risk in long-term users of vitamin K antagonists: A population-based case-control study

    DEFF Research Database (Denmark)

    Pottegård, Anton; Friis, Søren; Hallas, Jesper

    2013-01-01

    performed for selected cancer sites, subgroups and measures of exposure. A total of 238,196 cases and 1,713,176 controls were included. The adjusted OR for cancer associated with long-term VKA exposure was 0.99 (95% CI: 0.95–1.02). Long-term VKA use was associated with increased ORs for alcohol- or obesity-related...... a matched case–control analysis. We used data from four Danish nationwide registers. Cases were all Danish individuals with a first-time cancer diagnosis (except nonmelanoma skin cancer) between 2000 and 2009. For each case, eight controls, matched by birth year and gender, were selected from the source...... cancer sites, whereas we observed a decreased risk of prostate cancer (OR: 0.86; 95% CI: 0.78–0.95). Our study does not support a general chemopreventive effect of VKA drugs. However, in accordance with findings from previous studies, we found an inverse association between use of VKA and prostate cancer....

  14. Epigenetic profiles in children with a neural tube defect; a case-control study in two populations.

    Directory of Open Access Journals (Sweden)

    Lisette Stolk

    Full Text Available Folate deficiency is implicated in the causation of neural tube defects (NTDs. The preventive effect of periconceptional folic acid supplement use is partially explained by the treatment of a deranged folate-dependent one carbon metabolism, which provides methyl groups for DNA-methylation as an epigenetic mechanism. Here, we hypothesize that variations in DNA-methylation of genes implicated in the development of NTDs and embryonic growth are part of the underlying mechanism. In 48 children with a neural tube defect and 62 controls from a Dutch case-control study and 34 children with a neural tube defect and 78 controls from a Texan case-control study, we measured the DNA-methylation levels of imprinted candidate genes (IGF2-DMR, H19, KCNQ1OT1 and non-imprinted genes (the LEKR/CCNL gene region associated with birth weight, and MTHFR and VANGL1 associated with NTD. We used the MassARRAY EpiTYPER assay from Sequenom for the assessment of DNA-methylation. Linear mixed model analysis was used to estimate associations between DNA-methylation levels of the genes and a neural tube defect. In the Dutch study group, but not in the Texan study group we found a significant association between the risk of having an NTD and DNA methylation levels of MTHFR (absolute decrease in methylation of -0.33% in cases, P-value = 0.001, and LEKR/CCNL (absolute increase in methylation: 1.36% in cases, P-value = 0.048, and a borderline significant association for VANGL (absolute increase in methylation: 0.17% in cases, P-value = 0.063. Only the association between MTHFR and NTD-risk remained significant after multiple testing correction. The associations in the Dutch study were not replicated in the Texan study. We conclude that the associations between NTDs and the methylation of the MTHFR gene, and maybe VANGL and LEKKR/CNNL, are in line with previous studies showing polymorphisms in the same genes in association with NTDs and embryonic development

  15. Blastocystosis in patients with gastrointestinal symptoms: a case-control study.

    Science.gov (United States)

    Cekin, Ayhan Hilmi; Cekin, Yesim; Adakan, Yesim; Tasdemir, Ezel; Koclar, Fatma Gulsun; Yolcular, Basak Oguz

    2012-09-10

    Blastocystosis is a frequent bowel disease. We planned to to evaluate the prevalence of Blastocystis spp. in patients who applied to the same internal medicine-gastroenterology clinic with or without gastrointestinal complaints to reveal the association of this parasite with diagnosed IBS and IBD. A total of 2334 patients with gastrointestinal symptoms composed the study group, which included 335 patients with diagnosed inflammatory bowel disease and 877 with irritable bowel syndrome. Patients without any gastrointestinal symptoms or disease (n = 192) composed the control group. Parasite presence was investigated by applying native-Lugol and formol ethyl acetate concentration to stool specimens, and trichrome staining method in suspicious cases. Blastocystis spp. was detected in 134 patients (5.74%) in the study group and 6 (3.12%) in the control group (p = 0.128). In the study group, Blastocystis spp. was detected at frequencies of 8.7% in ulcerative colitis (24/276), 6.78% in Crohn's disease (4/59), 5.82% in irritable bowel syndrome (51/877), and 4.9% in the remaining patients with gastrointestinal symptoms (55/1122). Blastocystis spp. was detected at a statistically significant ratio in the inflammatory bowel disease (odds ratio [OR] = 2.824; 95% confidence interval [CI]: 1.149-6.944; p = 0.019) and ulcerative colitis (OR = 2.952; 95% CI: 1.183-7.367; p = 0.016) patients within this group compared to controls. There were no statistically significant differences between the control group and Crohn's disease or irritable bowel syndrome patients in terms Blastocystis spp. frequency (p = 0.251, p = 0.133). Blastocystosis was more frequent in patients with inflammatory bowel disease, especially those with ulcerative colitis. Although symptomatic irritable bowel syndrome and Crohn's disease patients had higher rates of Blastocystis spp. infection, the differences were not significant when compared to controls.

  16. A CASE-CONTROL STUDY OF CHILDHOOD BRAIN TUMORS AND FATHERS’ HOBBIES — A CHILDREN’S ONCOLOGY GROUP STUDY

    Science.gov (United States)

    Rosso, Andrea L.; Hovinga, Mary E.; Rorke-Adams, Lucy B.; Spector, Logan G.; Bunin, Greta R.

    2009-01-01

    Objective A comprehensive case-control study was conducted to evaluate parental risk factors for medulloblastoma (MB) and primitive neuroectodermal tumor (PNET). This analysis was conducted to evaluate associations between fathers’ hobbies and risk of their children developing MB/PNET. The hobbies chosen for study were those with similar exposures as occupations associated with childhood cancers. Methods Cases were 318 subjects under 6 years of age at diagnosis between 1991-1997 and registered with the Children’s Cancer Group. An equal number of controls were selected through random digit dialing and individually matched to cases. Results In multivariate analyses, a significant association was seen for lawn care with pesticides [during pregnancy: odds ratio (OR) = 1.6, 95% confidence interval (CI): 1.0, 2.5; after birth: OR = 1.8, 95% CI: 1.2, 2.8] and a weak association was seen for stripping paint [during pregnancy: OR = 1.4, 95% CI: 0.8, 2.6; after birth: OR = 1.4, 95% CI: 0.7, 2.6]. Conclusions This study suggests that household exposures from hobbies, particularly pesticides, may increase risk of MB/PNET in children; previous research has been mostly limited to occupational exposures. PMID:18560982

  17. Smoking and adult glioma: a population-based case-control study in China.

    Science.gov (United States)

    Hou, Lei; Jiang, Jingmei; Liu, Boqi; Han, Wei; Wu, Yanping; Zou, Xiaonong; Nasca, Philip C; Xue, Fang; Chen, Yuanli; Zhang, Biao; Pang, Haiyu; Wang, Yuyan; Wang, Zixing; Li, Junyao

    2016-01-01

    Smoking increases the risk of numerous cancers; however, an association of smoking with adult gliomas has not been found in a population. This case-control study included 4556 glioma cases (ICD-9 code 191.0-191.9) aged ≥ 30 years and 9112 controls from a national survey of smoking and mortality in China in 1989-1991. Controls from 325 255 surviving spouses of all-cause deaths were randomly assigned to cases in each of 103 areas according to sex and age groups at a ratio of 2:1. Smoking information was ascertained retrospectively by interviewing surviving spouses. After adjustment for confounders, smoking increased the risk of glioma deaths by 11% (odds ratio [OR] = 1.11; 95% confidence interval [CI]: 1.03-1.21). Compared with non-smokers; the increased risk was 9% (OR = 1.09; 95% CI: 0.99-1.20) in men and 16% (OR = 1.16; 95% CI: 1.00-1.36) in women. The risk increased with age and doses. For individuals aged ≥ 50 years, smoking was associated with higher risk of glioma death by 25% (OR = 1.25; 95% CI: 1.15-1.38); this increased risk for smokers who smoked ≥ 20 cigarettes daily for ≥ 30 years was 53% (OR = 1.53; 95% CI: 1.34-1.74). There were similar findings in both men and women and with either pathology-based or non-pathology-based comparisons. This study indicates that smoking is associated with glioma deaths in the Chinese population. Long-term heavy smoking could be a factor for risk stratification in individuals attending brain tumor clinics. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Insertion/deletion polymorphism of ACE gene in females with peripartum cardiomyopathy: A case-control study.

    Science.gov (United States)

    Yaqoob, Irfan; Tramboo, Nisar A; Bhat, Irfan A; Pandith, Arshad; Beig, Jahangir R; Hafeez, Imran; Lone, Aijaz A; Shah, Tariq R; Samreen, Sumera

    The role of polymorphism of Angiotensin converting enzyme (ACE) gene and ACE activity in etiopathogenesis, prognosis, and many other clinical parameters in the various form of the cardiovascular disease has been established to some degree of certainty. The pathophysiology of Peripartum cardiomyopathy (PPCM) remains an area of active research. The main aim of our study was to see pattern of ACE- Insertion/Deletion (I/D) allele in PPCM and its implications on left ventricular performance indices. This single-center case-control study included 45 cases and 70 controls. The diagnosis of PPCM was established clinically and echocardiographically. ACE genotyping was done by polymerase chain reaction (PCR) method in all subjects. The II, ID, and DD genotype was present in 16, 18 and 11 of subjects with PPCM and 48, 19 and 3 of controls respectively. The odds ratio for ACE-II genotype in cases vs. controls was 0.253 (95% CI=0.114-0.558; p=0.007), for that of II genotype was 1.93 (95% CI=0.86-4.3; p=0.107) and for DD genotype was 7.225 (95% CI; 1.88-27.6; p=0.0039). Overall frequency of D allele in cases was significantly higher than controls (odds=4.25; 95% CI=2.01-6.7; p=0.0001). Moreover, ejection fraction, left ventricular volume and linear dimensions were worse in patients with DD genotype. ACE DD genotype and overall frequency of D allele is significantly higher in patients with PPCM. Also, the presence of DD genotype is associated with worse systolic performance indices measured echocardiographically. Copyright © 2017. Published by Elsevier B.V.

  19. Maternal Risk Factors for Oral Clefts: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Elham Mobasheri

    2011-01-01

    Full Text Available Introduction: A cleft lip with or without a cleft palate is one of the major congenital anomalies observed in newborns. This study explored the risk factors for oral clefts in Gorgan, Northern Iran.  Materials and Methods: This hospital-based case-control study was performed in three hospitals in Gorgan, Northern Iran between April 2006 and December 2009. The case group contained 33 newborns with oral clefts and the control group contained 63 healthy newborns. Clinical and demographic factors, including date of birth, gender of the newborns, type of oral cleft, consanguinity of the parents, parental ethnicity, and the mother's parity, age, education and intake of folic acid were recorded for analysis.  Results: A significant association was found between parity higher than 2 and the risk of an oral cleft (OR= 3.33, CI 95% [1.20, 9.19], P> 0.02. According to ethnicity, the odds ratio for oral clefts was 0.87 in Turkmens compared with Sistani people (CI 95% [0.25, 2.96] and 1.11 in native Fars people compared with Sistani people (CI 95% [0.38, 3.20]. A lack of folic acid consumption was associated with an increased risk of oral clefts but this was not statistically significant (OR = 1.42, CI 95% [0.58, 3.49]. There were no significant associations between sex (OR boy/girl = 0.96, CI 95% [0.41, 2.23], parent familial relations (OR = 1.07, CI 95% [0.43, 2.63], mother's age and oral clefts.  Conclusions:  The results of this study indicate that higher parity is significantly associated with an increased risk of an oral cleft, while Fars ethnicity and a low intake of folic acid increased the incidence of oral clefts but not significantly.

  20. Risk factors for maternal mortality in the west of Iran: a nested case-control study

    Directory of Open Access Journals (Sweden)

    Jalal Poorolajal

    2014-11-01

    Full Text Available OBJECTIVES: With a gradual decline in maternal mortality in recent years in Iran, this study was conducted to identify the remaining risk factors for maternal death. METHODS: This 8-year nested case-control study was conducted in Hamadan Province, in the west of Iran, from April 2006 to March 2014. It included 185 women (37 cases and 148 controls. All maternal deaths that occurred during the study period were considered cases. For every case, four women with a live birth were selected as controls from the same area and date. Conditional logistic regression analysis was performed and the odds ratio (OR and its 95% confidence interval (CI were obtained for each risk factor. RESULTS: The majority of cases were aged 20-34 years, died in hospital, and lived in urban areas. The most common causes of death were bleeding, systemic disease, infection, and pre-eclampsia. The OR estimate of maternal death was 8.48 (95% CI=1.26-56.99 for advanced maternal age (≥35 years; 2.10 (95% CI=0.07-65.43 for underweight and 10.99 (95% CI=1.65-73.22 for overweight or obese women compared to those with normal weight; 1.56 (95% CI=1.08-2.25 for every unit increase in gravidity compared to those with one gravidity; 1.73 (95% CI=0.34-8.88 for preterm labors compared to term labors; and 17.54 (95% CI= 2.71-113.42 for women with systemic diseases. CONCLUSIONS: According to our results, advanced maternal age, abnormal body mass index, multiple gravidity, preterm labor, and systemic disease were the main risk factors for maternal death. However, more evidence based on large cohort studies in different settings is required to confirm our results.

  1. [High-grade pressure sores in frail older high-risk persons. A retrospective postmortem case-control-study].

    Science.gov (United States)

    Von Renteln-Kruse, W; Krause, T; Anders, J; Kühl, M; Heinemann, A; Püschel, K

    2004-04-01

    Some old persons at risk do develop, but others, at comparable risk, do not develop high-grade pressure sores. To evaluate potentially different risk factors, we performed a post mortem case-control study in old persons who developed high-grade pressure sores within six months until 14 days before death. Consecutive cases with pressure sores grade >/=3 and potential controls at comparably high risk for pressure sores were examined before cremation. After written informed consent had been obtained by the next relatives, all available nursing and medical records of the deceased were thoroughly evaluated. Cases and controls were matched according to age, gender, immobility, and cachexia.A total of 100 cases with 71 pressure sores grade 3 and 29 pressure sores grade 4 were compared to 100 controls with 27 pressure sores grade pressure sores in frail older high-risk persons. Sedative drug effects and impaired patient compliance with preventive and therapeutic measures may also be associated with the development of high-grade pressure sores in old persons at high risk.

  2. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Energy Technology Data Exchange (ETDEWEB)

    Ozana, Stepan, E-mail: stepan.ozana@vsb.cz; Pies, Martin, E-mail: martin.pies@vsb.cz; Docekal, Tomas, E-mail: docekalt@email.cz [VSB-Technical University of Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Cybernetics and Biomedical Engineering, 17. listopadu 15/2172, Ostrava-Poruba, 700 30 (Czech Republic)

    2016-06-08

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  3. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    International Nuclear Information System (INIS)

    Ozana, Stepan; Pies, Martin; Docekal, Tomas

    2016-01-01

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  4. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Science.gov (United States)

    Ozana, Stepan; Pies, Martin; Docekal, Tomas

    2016-06-01

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  5. Recent food shortage is associated with leprosy disease in Bangladesh: a case-control study.

    Directory of Open Access Journals (Sweden)

    Sabiena G Feenstra

    Full Text Available BACKGROUND: Leprosy is remaining prevalent in the poorest areas of the world. Intensive control programmes with multidrug therapy (MDT reduced the number of registered cases in these areas, but transmission of Mycobacterium leprae continues in most endemic countries. Socio-economic circumstances are considered to be a major determinant, but uncertainty exists regarding the association between leprosy and poverty. We assessed the association between different socio-economic factors and the risk of acquiring clinical signs of leprosy. METHODS AND FINDINGS: We performed a case-control study in two leprosy endemic districts in northwest Bangladesh. Using interviews with structured questionnaires we compared the socio-economic circumstances of recently diagnosed leprosy patients with a control population from a random cluster sample in the same area. Logistic regression was used to compare cases and controls for their wealth score as calculated with an asset index and other socio-economic factors. The study included 90 patients and 199 controls. A recent period of food shortage and not poverty per se was identified as the only socio-economic factor significantly associated with clinical manifestation of leprosy disease (OR 1.79 (1.06-3.02; p = 0.030. A decreasing trend in leprosy prevalence with an increasing socio-economic status as measured with an asset index is apparent, but not statistically significant (test for a trend: OR 0.85 (0.71-1.02; p = 0.083. CONCLUSIONS: Recent food shortage is an important poverty related predictor for the clinical manifestation of leprosy disease. Food shortage is seasonal and poverty related in northwest Bangladesh. Targeted nutritional support for high risk groups should be included in leprosy control programmes in endemic areas to reduce risk of disease.

  6. Intrapartum amnioinfusion in meconium-stained liquor: a case-control study.

    Science.gov (United States)

    Bansal, Neeta; Gupta, Vineeta; Nanda, Anuja; Chaudhary, Priyanka; Tandon, Archna; Behl, Neelima

    2013-06-01

    The aim of this study was to investigate perinatal outcome and the rate of cesarean section (CS) following intrapartum amnioinfusion in women with meconium-stained amniotic fluid (MSAF). A total of 100 women at term in labor with meconium were randomized to infuse transcervical intrapartum amnioinfusion with saline (50) and routine obstetrical care (50). Perinatal outcome and obstetric outcome were recorded and analyzed in both groups by means of Chi-square test. The CS rate due to fetal distress was 40.0 % in the control group and 20.0 % in the study group. The difference was statistically significant (P Amnioinfusion in cases of meconium-stained liquor significantly improved neonatal outcome and CS rate without increasing any maternal and fetal complications.

  7. What factors play a role in preventing self-immolation?Results from a case-control study in Iran

    Directory of Open Access Journals (Sweden)

    Hosein Karim

    2015-07-01

    Full Text Available Abstract: Background: To investigate factors related to prevention of self-immolation in west of Iran. Methods: In a case-control study, 30 consecutive cases of deliberate self-inflicted burns admitted to the regional burn center (Imam Khomeini hospital in Kermanshah province, Iran were compared with controls selected from the community and matched by sex, age,district-county of residence, and rural vs urban living environment. The following characteristics relevant to preventing self immolation were collected from all cases and controls: main domestic fuel used in the household, awareness about complications of burn injuries, and use of counseling services. Results: Descriptive analyses revealed that kerosene was the main domestic fuel in the household for 83% of cases. Not surprisingly, the main means of self-immolation in 93% of the patients was kerosene, with other fuels such as petrol and domestic gas used in remaining cases. The majority of cases and controls were aware of the potential complications of burn injuries. Use of counseling services was more common in controls. Conclusions: All three aspects of preventing self-immolation – having kerosene and other fuels in the home, being aware of the complications of burn injuries, and using counseling services were present in both the cases and controls. This suggests a large portion of residents in rural Iran are potential self-immolation victims. Increasing preventive strategies may reduce risk of suicide by self-immolation.

  8. Hearing Loss is Associated With Risk of Alzheimer’s Disease: A Case-Control Study in Older People

    OpenAIRE

    Shih-Chang Hung; Kuan-Fu Liao; Chih-Hsin Muo; Shih-Wei Lai; Chia-Wei Chang; Hung-Chang Hung

    2015-01-01

    Background: It remains unknown whether hearing loss increases the risk of Alzheimer’s disease. This study aimed to examine the association between hearing loss and risk of Alzheimer’s disease in older people in Taiwan. Methods: Analyzing the database from Taiwan’s National Health Insurance Program, this case-control study enrolled 488 subjects ≥65 years old with newly diagnosed Alzheimer’s disease as a case group and 1952 subjects without Alzheimer’s disease as a control group from 1998–20...

  9. Neurovascular alterations in chronic hepatitis C: a case-control study

    Directory of Open Access Journals (Sweden)

    Valentina Vedovetto

    2013-03-01

    Full Text Available Introduction: Hepatitis C is a major health problem: approximately 170 million people are infected with the hepatitis C virus worldwide. It is unclear whether chronic hepatitis C affects atherosclerosis and whether it can cause endothelial and/or autonomic nervous system (ANS dysfunction. Materials and methods: From April 2008 through April 2009, we studied 76 patients with biopsyconfirmed chronic hepatitis C and no evidence of cirrhosis, ascites, portal hypertension, encephalopathy, or hepatocellular carcinoma. The age-, sex-, BMI- and cardiovascular risk factor- matched control group comprised 76 healthy, HCV-negative individuals with no evidence of liver, autoimmune, or immunoproliferative diseases and no history of cardiovascular events. Twenty five of the hepatitis C patients were treatment-naive; the other 51 had been treated with interferon (but only 25 had persistent virological responses. Color Doppler sonography was used to measure the intima-media-thickness (IMT of the common and internal carotid arteries. Endothelial function was assessed in the brachial artery with the flow-mediated-dilatation (FMD test. The ANS was assessed with the tilt, laying to standing, Valsalva, hand grip, deep breath, and stroop tests. Results: The case group (mean age 52 + 13 years had a significantly higher internal carotid IMT (0.86 + 0.3 vs 0.67 + 0.1 mmfor controls; p = 0.002. Chronic hepatitis C was also associated with an odds ratio for carotid plaque formation (reflected by an IMT > 1.3 mm of 2.15. Cases also had significantly reduced FMD in the brachial artery (0.46 + 0.9 vs 0.76 + 0.7 for controls; p = 0.005 and significantly altered sympathetic and parasympathetic function (p = 0.001 vs controls in the Valsalva, hand grip, deep breath, and stroop tests. Within the case group, all alterations were more severe in patients with significant viremia. Discussion: Our findings suggest that chronic hepatitis C may be a nonclassic cardiovascular risk

  10. Case-control study of genus-beta human papillomaviruses in plucked eyebrow hairs and cutaneous squamous cell carcinoma.

    Science.gov (United States)

    Iannacone, Michelle R; Gheit, Tarik; Pfister, Herbert; Giuliano, Anna R; Messina, Jane L; Fenske, Neil A; Cherpelis, Basil S; Sondak, Vernon K; Roetzheim, Richard G; Silling, Steffi; Pawlita, Michael; Tommasino, Massimo; Rollison, Dana E

    2014-05-01

    Cutaneous human papillomaviruses (HPV) have been reported in cutaneous squamous cell carcinoma (SCC). We conducted a clinic-based case-control study to investigate the association between genus-beta HPV DNA in eyebrow hairs (EBH) and SCC. EBH from 168 SCC cases and 290 controls were genotyped for genus-beta HPV DNA. SCC tumors from a subset of cases (n = 142) were also genotyped. Viral load was determined in a subset of specimens positive for a single HPV type. Associations with SCC were estimated by odds ratios (OR) and 95% confidence intervals (CI) adjusted for age and sex using logistic regression. Statistical tests were two-sided. EBH DNA prevalence was greater in cases (87%) than controls (73%) (p genus-beta types tested, when accounting for DNA for the same HPV type in the tumor (ORs = 3.44-76.50). Compared to controls, the mean viral DNA load in EBH among the selected cases was greater for HPV5, HPV8 and HPV24, but lower for HPV38. SCC cases were more likely than controls to have HPV DNA+ EBH for single and multiple HPV types, providing additional support for the potential role of genus-beta HPV infections in SCC development. © 2013 UICC.

  11. Anorexia nervosa versus bulimia nervosa : differences based on retrospective correlates in a case-control study

    NARCIS (Netherlands)

    Machado, Barbara C.; Goncalves, Sonia F.; Martins, Carla; Brandao, Isabel; Roma-Torres, Antonio; Hoek, Hans W.; Machado, Paulo P.

    This study is the result of two Portuguese case-control studies that examined the replication of retrospective correlates and preceding life events in anorexia nervosa (AN) and bulimia nervosa (BN) development. This study aims to identify retrospective correlates that distinguish AN and BN A

  12. Is infertility a risk factor for female sexual dysfunction? A case-control study.

    Science.gov (United States)

    Millheiser, Leah S; Helmer, Amy E; Quintero, Rodolfo B; Westphal, Lynn M; Milki, Amin A; Lathi, Ruth B

    2010-11-01

    To determine the impact of infertility on female sexual function. A case-control study. Academic infertility and gynecology practices. One hundred nineteen women with infertility and 99 healthy female controls without infertility between the ages of 18 and 45 years were included in this study. Anonymous survey and Female Sexual Function Index. Female Sexual Function Index scores, frequency of sexual intercourse and masturbation, and sex-life satisfaction. Twenty-five percent of our control group had Female Sexual Function Index scores that put them at risk for sexual dysfunction (masturbation. The patients with infertility retrospectively reported a sex-life satisfaction score that was similar to that of the controls before their diagnosis, whereas their current sex-life satisfaction scores were significantly lower than those of the controls. Women with a diagnosis of infertility were found to be at higher risk for sexual dysfunction on the basis of their Female Sexual Function Index scores compared with women without infertility. The interaction of sexual function and infertility is complex and deserves further study. Copyright © 2010. Published by Elsevier Inc.

  13. Sudden Unexpected Death During Sleep in Familial Dysautonomia: A Case-Control Study.

    Science.gov (United States)

    Palma, Jose-Alberto; Norcliffe-Kaufmann, Lucy; Perez, Miguel A; Spalink, Christy L; Kaufmann, Horacio

    2017-08-01

    Sudden unexpected death during sleep (SUDS) is the most common cause of death in patients with familial dysautonomia (FD), an autosomal recessive disease characterized by sensory and autonomic dysfunction. It remains unknown what causes SUDS in these patients and who is at highest risk. We tested the hypothesis that SUDS in FD is linked to sleep-disordered breathing. We retrospectively identified patients with FD who died suddenly and unexpectedly during sleep and had undergone polysomnography within the 18-month period before death. For each case, we sampled one age-matched surviving subject with FD that had also undergone polysomnography within the 18-month period before study. Data on polysomnography, EKG, ambulatory blood pressure monitoring, arterial blood gases, blood count, and metabolic panel were analyzed. Thirty-two deceased cases and 31 surviving controls were included. Autopsy was available in six cases. Compared with controls, participants with SUDS were more likely to be receiving treatment with fludrocortisone (odds ratio [OR]; 95% confidence interval) (OR 29.7; 4.1-213.4), have untreated obstructive sleep apnea (OR 17.4; 1.5-193), and plasma potassium levels Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  14. Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study.

    Science.gov (United States)

    Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A; Chavarro, Jorge E; Toledo, Estefania

    2015-07-27

    The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72-1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72-1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82-1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84-1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women's fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

  15. Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

    Directory of Open Access Journals (Sweden)

    Cristina Lopez-del Burgo

    2015-07-01

    Full Text Available The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72–1.51. No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72–1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82–1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84–1.64 was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women’s fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

  16. Relationship of Psychosocial Risk Factors, Certain Personality Traits and Myocardial Infarction in Indians: A Case-control Study.

    Science.gov (United States)

    Gupta, Rajni; Kishore, Jugal; Bansal, Yogesh; Daga, Mk; Jiloha, Rc; Singal, Rajeev; Ingle, Gk

    2011-07-01

    To investigate the relationship of psychosocial factors (lack of social support, stress and subjective well-being) and personality traits with myocardial infarction (MI). A case-control study involving 100 cases and 100 matched controls was conducted in Lok Nayak Hospital, New Delhi. Stress over 1 year was significantly higher in cases (P introvert (P < 0.001) personalities. Certain personality traits and recent stress may be important risk factors of MI, especially in Indians. The finding may have implications on the preventive strategies planned for MI patients.

  17. Peculiar alexithymic traits in burning mouth syndrome: case-control study.

    Science.gov (United States)

    Marino, Roberto; Picci, Rocco Luigi; Ferro, Giovanni; Carezana, Claudio; Gandolfo, Sergio; Pentenero, Monica

    2015-11-01

    The present case-control study aims to assess the occurrence of alexithymic traits in burning mouth syndrome (BMS) subjects and to correlate alexithymic traits to anxious and depressive traits in BMS subjects. Prospectively enrolled BMS and control subjects were administered the 20-item Toronto Alexithymia Scale (TAS-20). Anxiety and depressive traits were assessed using the Hamilton Anxiety Rating Scale and the Montgomery and Asberg Depression Rating Scale. Occurrence of alexithymic traits was compared between BMS and control subjects. Correlation tests were used to measure the importance of alexithymic traits related to demographic characteristics, pain intensity (VAS score), and to the other psychometric scores. Fifty-eight BMS subjects (46 females and 12 males) had a mean TAS-20 score significantly higher when compared to controls (p < 0.001; r = 0.72), corresponding to an occurrence rate of alexithymic traits of 79.3 versus 6.9%. Alexithymic traits in BMS subjects were just related to depressive traits (p = 0.02; ρ = 0.31). The high occurrence of alexithymia in BMS is an adjunctive issue in favor of its multifactorial pathogenesis, with a not negligible role for somatization. Clinicians should be aware of the high occurrence of alexithymic traits among BMS subjects as such traits may affect the doctor-patient relationship.

  18. [Lack of association between MMR vaccination and the incidence of autism in children: a case-control study].

    Science.gov (United States)

    Mrozek-Budzyn, Dorota; Kiełtyka, Agnieszka; Majewska, Renata

    2009-01-01

    The matched case-control study has been undertook to investigate whether measles, mumps, and rubella (MMR) vaccine may be casually associated with autism in children. Cases were children to 14-year old with diagnosis of core autism or atypical autism. Controls were matched on age, sex and general practice. The 96 cases and 192 controls were included. The study provides strong evidence against association of autism with both MMR and a single measles individual vaccine. Additionally children vaccinated with MMR, regardless of age of vaccination (to 18th, 24th and 36th month of life), had risk equal half of that of single measles vaccinated (for vaccinated to 18th month OR=0.41 95%PU: 0.20-0.85). Our findings confirm that MMR vaccination is not associated with an increased risk of autism in children.

  19. Assessment of financial control practices in Polytechnics in Ghana. A case study of Sunyani Polytechnic

    OpenAIRE

    Prempeh, Kwadwo Boateng; Twumasi, Patrick; Kyeremeh, Kwadwo

    2015-01-01

    The study sought to assess the financial Control systems of Polytechnics in Ghana and suggest ways of improving them. Financial control systems exist to help organizations meet their goals and objectives, promote efficiency, reduce the risk of loss, and help ensure financial statement reliability and compliance with laws and regulations. The study adopts the case study design using Sunyani Polytechnic in the Brong Ahafo region, Ghana. A sample size of 50 staff members was selected for the stu...

  20. Familial colorectal cancer, can it be identified by microsatellite instability and chromosomal instability? - A case-control study

    DEFF Research Database (Denmark)

    Sunde, Lone; Bisgaard, Marie Luise; Soll-Johanning, Helle

    2009-01-01

    (Chromosome INstability=LOH (loss of heterozygosity) and/or DNA-aneuploidy (abnormal nuclear DNA contents)) could be used as predictors of familial CRC. Formalin-fixed tissue from 97 patients with CRC (29 patients with 2 or more affected first-degree relatives (="cases"), 29 matched CRC controls without......Colonoscopy is recommended for persons with a familial risk of colorectal cancer (CRC). A familial risk is identified by a family history with CRC and/or predisposing mutation(s). However, such information may not be available. We analysed whether MSI (MicroSatellite Instability) and/or CIN...... a family history, and 39 relatives to cases) were analysed for MSI and CIN. In this small case-control study, no significant differences in the frequencies of MSI and CIN were observed between cases with a family history and their controls without a family history. MSI+;CIN- was observed in 6/29 cases...

  1. Associated factors and outcomes for OXA-232 Carbapenem-resistant Enterobacteriaceae infections in a tertiary care centre in Mexico City: A case-control-control study.

    Science.gov (United States)

    Torres-González, Pedro; Ortiz-Brizuela, Edgar; Cervera-Hernandez, Miguel Enrique; Bobadilla-Del Valle, Miriam; Martínez-Gamboa, Areli; Sifuentes-Osornio, José; Ponce-de-Leon, Alfredo

    2016-10-01

    We describe the outcomes and factors associated with OXA-232 producing carbapenem-resistant Enterobacteriaceae infections. A case-control-control study was performed; each case of infection by a carbapenem-resistant/OXA-232 (OXA-232-cases, n=27) was matched by isolation site, species, and date, with 2 cases of infection by carbapenem-susceptible/third-generation cephalosporin-susceptible (TGCS-controls, n=54) and 2 cases by carbapenem-susceptible/ESBL producing Enterobacteriaceae (ESBL-controls, n=54); 66% were urinary tract and 18.5% intra-abdominal infections. In the multivariable analysis with ESBL-controls, previous use β-lactam/β-lactamase antibiotics (OR 6.2; 95% CI 1.6-23.8) and, third-generation cephalosporins (OR 0.2; 95% CI 0.05-0.8) were associated with OXA-232 infection; with TGSC-controls previous use of β-lactam/β-lactamase antibiotics (OR 3.7; 95% 1.1-12.0) was associated. Among the OXA-232-cases, 29% received imipenem/cilastatin or meropenem, 11.1% ceftriaxone, 22.2% a carbapenem-based combination and 33.3% other antimicrobials as treatment. Previous β-lactam/β-lactamase antibiotics are associated with OXA-232 infections, and some may be treated with other active carbapenems or, in the absence of ESBL, third-generation cephalosporins. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Occupational Lifting Tasks and Retinal Detachment in Non-Myopics and Myopics: Extended Analysis of a Case-control Study

    OpenAIRE

    Mattioli, Stefano; Curti, Stefania; De Fazio, Rocco; Cooke, Robin Mt; Zanardi, Francesca; Bonfiglioli, Roberta; Farioli, Andrea; Violante, Francesco S.

    2012-01-01

    Objectives: Lifting heavy weights involves the Valsalva manoeuvre, which leads to intraocular pressure spikes. We used data from a case-control study to further investigate the hypothesis that occupational lifting is a risk factor for retinal detachment. Methods: The study population included 48 cases (patients operated for retinal detachment) and 84 controls (outpatients attending an eye clinic). The odds ratios (OR) of idiopathic retinal detachment were estimated with a logistic regressi...

  3. Anorexia nervosa versus bulimia nervosa: differences based on retrospective correlates in a case-control study.

    Science.gov (United States)

    Machado, Bárbara C; Gonçalves, Sónia F; Martins, Carla; Brandão, Isabel; Roma-Torres, António; Hoek, Hans W; Machado, Paulo P

    2016-06-01

    This study is the result of two Portuguese case-control studies that examined the replication of retrospective correlates and preceding life events in anorexia nervosa (AN) and bulimia nervosa (BN) development. This study aims to identify retrospective correlates that distinguish AN and BN METHOD: A case-control design was used to compare a group of women who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for AN (N = 98) and BN (N = 79) with healthy controls (N = 86) and with other psychiatric disorders (N = 68). Each control group was matched with AN patients regarding age and parental social categories. Risk factors were assessed by interviewing each person with the Oxford Risk Factor Interview. Compared to AN, women with BN reported significantly higher rates of paternal high expectations, excessive family importance placed on fitness/keeping in shape, and negative consequences due to adolescent overweight and adolescent objective overweight. Overweight during adolescence emerged as the most relevant retrospective correlate in the distinction between BN and AN participants. Family expectations and the importance placed on keeping in shape were also significant retrospective correlates in the BN group.

  4. ICOS gene polymorphisms are associated with sporadic breast cancer: a case-control study

    International Nuclear Information System (INIS)

    Xu, Fengyan; Li, Dalin; Zhang, Qiujin; Fu, Zhenkun; Zhang, Jie; Yuan, Weiguang; Chen, Shuang; Pang, Da; Li, Dianjun

    2011-01-01

    Inducible costimulator (ICOS), a costimulatory molecular of the CD28 family, provides positive signal to enhance T cell proliferation. Its abnormal expression can disturb the immune response and entail an increased risk of cancer. To investigate whether single nucleotide polymorphisms (SNPs) in the ICOS gene are associated with sporadic breast cancer susceptibility and progression in Chinese women, a case-control study was conducted. In the study cohort, we genotyped five SNPs (rs11889031, rs10932029, rs4675374, rs10183087 and rs10932037) in ICOS gene among 609 breast cancer patients and 665 age-matched healthy controls. Furthermore, the positive results were replicated in an independent validation cohort of 619 patients and 682 age-matched healthy controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the genotypes. In rs10932029, compared with TT genotype and T allele, the CT genotype and C allele showed a significantly increased risk of breast cancer (P = 0.030, OR = 1.467, 95% CI 1.037-2.077; P = 0.017, OR = 1.481, 95% CI 1.070-2.049, respectively), and the associations were also significant in the validation cohort (P = 0.002, OR = 1.693, 95% CI 1.211-2.357; P = 0.003, OR = 1.607, 95% CI 1.171-2.204, respectively). Haplotype analysis showed that CTCAC haplotype containing rs10932029 T allele had a lower frequency in cases than in controls (P = 0.015), whereas haplotype CCCAC containing rs10932029 C allele was more common in cases than in controls (P = 0.013). In the analysis of clinicopathologic features, rs11889031 CT genotype and T allele were associated with progesterone receptor (PR) status and lymph node metastasis, which were further supported by our validation cohort. Moreover, some haplotypes were associated with estrogen receptor (ER) and PR statuses. These results indicate that ICOS gene polymorphisms may affect the risk of breast cancer and show that some SNPs are associated with breast cancer

  5. Appendectomy and Risk of Subsequent Diverticular Disease Requiring Hospitalization: A Population-Based Case-Control Study.

    Science.gov (United States)

    Sköldberg, Filip; Olén, Ola; Ekbom, Anders; Schmidt, Peter T

    2018-07-01

    Appendicitis and acute diverticulitis share clinical features and are both influenced by genetic and environmental factors. Appendectomy has been positively associated with diverticular disease in hospital-based case-control studies. The aim of the present study was to investigate, in a population-based setting, whether appendectomy, with or without appendicitis, is associated with an altered risk of hospitalization with diverticular disease. This was a population-based case-control study. The study was based on national healthcare and population registers. We studied 41,988 individuals hospitalized between 2000 and 2010 with a first-time diagnosis of colonic diverticular disease and 413,115 matched control subjects. The association between appendectomy with or without appendicitis and diverticular disease was investigated by conditional logistic regression, including a model adjusting for hospital use. A total of 2813 cases (6.7%) and 19,037 controls (4.6%) had a previous record of appendectomy (appendectomy with acute appendicitis: adjusted OR = 1.31 (95% CI, 1.24-1.39); without appendicitis: adjusted OR = 1.30 (95% CI, 1.23-1.38)). Appendectomy was most strongly associated with an increased risk of diverticular disease within 1 year (with appendicitis: adjusted OR = 2.26 (95% CI, 1.61-3.16); without appendicitis: adjusted OR = 3.98 (95% CI, 2.71-5.83)), but the association was still present ≥20 years after appendectomy (with appendicitis: adjusted OR = 1.22 (95% CI, 1.12-1.32); without appendicitis: adjusted OR = 1.19 (95% CI, 1.10-1.28)). Detailed clinical information on the cases was not available. There were unmeasured potential confounders, such as smoking and dietary factors. The findings are consistent with a hypothesis of appendectomy causing an increased risk of diverticular disease, for example, by affecting the mucosal immune system or the gut microbiome. However, several other mechanisms may contribute to, or account for, the positive association

  6. Breast Cancer and Modifiable Lifestyle Factors in Argentinean Women: Addressing Missing Data in a Case-Control Study

    Science.gov (United States)

    Coquet, Julia Becaria; Tumas, Natalia; Osella, Alberto Ruben; Tanzi, Matteo; Franco, Isabella; Diaz, Maria Del Pilar

    2016-01-01

    A number of studies have evidenced the effect of modifiable lifestyle factors such as diet, breastfeeding and nutritional status on breast cancer risk. However, none have addressed the missing data problem in nutritional epidemiologic research in South America. Missing data is a frequent problem in breast cancer studies and epidemiological settings in general. Estimates of effect obtained from these studies may be biased, if no appropriate method for handling missing data is applied. We performed Multiple Imputation for missing values on covariates in a breast cancer case-control study of Córdoba (Argentina) to optimize risk estimates. Data was obtained from a breast cancer case control study from 2008 to 2015 (318 cases, 526 controls). Complete case analysis and multiple imputation using chained equations were the methods applied to estimate the effects of a Traditional dietary pattern and other recognized factors associated with breast cancer. Physical activity and socioeconomic status were imputed. Logistic regression models were performed. When complete case analysis was performed only 31% of women were considered. Although a positive association of Traditional dietary pattern and breast cancer was observed from both approaches (complete case analysis OR=1.3, 95%CI=1.0-1.7; multiple imputation OR=1.4, 95%CI=1.2-1.7), effects of other covariates, like BMI and breastfeeding, were only identified when multiple imputation was considered. A Traditional dietary pattern, BMI and breastfeeding are associated with the occurrence of breast cancer in this Argentinean population when multiple imputation is appropriately performed. Multiple Imputation is suggested in Latin America’s epidemiologic studies to optimize effect estimates in the future. PMID:27892664

  7. Long-term outcomes of patients with Streptococcus suis infection in Viet Nam: A case-control study.

    Science.gov (United States)

    Huong, Vu T L; Long, Hoang B; Kinh, Nguyen V; Ngan, Ta T D; Dung, Vu T V; Nadjm, Behzad; van Doorn, H Rogier; Hoa, Ngo T; Horby, Peter; Wertheim, Heiman F L

    2018-02-01

    Streptococcus suis is a zoonotic cause of severe meningitis and sepsis in humans. We aimed to assess the long-term outcomes in patients who survived S. suis infection, in particular the progress and impact of vestibulocochlear sequelae. This case-control study evaluated outcomes of S. suis infection at discharge and 3 and 9 months post-discharge for 47 prospectively enrolled cases and at 11-34 months for 31 retrospectively enrolled cases. Outcomes in patients were compared to 270 controls matched for age, sex and residency. The prevalence ratio (PR) of moderate-to-complete hearing loss was 5.0(95%CI 3.6-7.1) in cases at discharge, 3.7(2.5-5.4) at 3 months, 3.2(2.2-4.7) at 9 months, and 3.1(2.1-4.4) in retrospective cases compared to controls. Hearing improvement occurred mostly within the first 3 months with a change in hearing level of 11.1%(95%CI 7.0-15.1%) compared to discharge. The PR of vestibular dysfunction was 2.4(95%CI 1.7-3.3) at discharge, 2.2(1.4-3.1) at 3 months, 1.8(1.1-2.5) at 9 months, and 1.8(1.1-2.6) for retrospective cases compared to controls. Cases also indicated more problems with mobility, self-care and usual activities. Both hearing and vestibular impairment were common and persist in cases. Appropriate patient management strategies are needed to reduce the incidence and impact of these sequelae. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Simple Algorithms to Calculate Asymptotic Null Distributions of Robust Tests in Case-Control Genetic Association Studies in R

    Directory of Open Access Journals (Sweden)

    Wing Kam Fung

    2010-02-01

    Full Text Available The case-control study is an important design for testing association between genetic markers and a disease. The Cochran-Armitage trend test (CATT is one of the most commonly used statistics for the analysis of case-control genetic association studies. The asymptotically optimal CATT can be used when the underlying genetic model (mode of inheritance is known. However, for most complex diseases, the underlying genetic models are unknown. Thus, tests robust to genetic model misspecification are preferable to the model-dependant CATT. Two robust tests, MAX3 and the genetic model selection (GMS, were recently proposed. Their asymptotic null distributions are often obtained by Monte-Carlo simulations, because they either have not been fully studied or involve multiple integrations. In this article, we study how components of each robust statistic are correlated, and find a linear dependence among the components. Using this new finding, we propose simple algorithms to calculate asymptotic null distributions for MAX3 and GMS, which greatly reduce the computing intensity. Furthermore, we have developed the R package Rassoc implementing the proposed algorithms to calculate the empirical and asymptotic p values for MAX3 and GMS as well as other commonly used tests in case-control