WorldWideScience

Sample records for subjective workload measures

  1. Cultural influences on the measurement of subjective mental workload

    NARCIS (Netherlands)

    Johnson, Addie; Widyanti, Ari

    2011-01-01

    Cognitive ergonomics is well entrenched in North American and most European work environments, where systems and products are designed with the capabilities and limitations of the user in mind. A prominent technique for analysing task demands is subjective mental workload measurement. Subjective

  2. On the psychophysics of workload - Why bother with subjective measures?

    Science.gov (United States)

    Gopher, D.; Braune, R.

    1984-01-01

    Psychophysical functions describe the relationship between variations in the amplitude of a defined physical quantity and the psychological perception of these changes. Examples are brightness, loudness, and pain. The regularities of these relationships have been formulated into psychophysical laws. The measurement methodology of psychophysical scaling has been refined by the Harvard group led by Stevens (1957 and 1966), who proposed a power function as a general form for such laws. It is argued here that a similar scaling approach can be adapted to the measurement of workload and task demands based upon subjective estimates. The rationale is that these estimates, like other psychophysical judgments, reflect the individual's perception of the amount of processing resources that the subject invests to meet the demand imposed by a task. This approach was successfully applied to the assessment of 21 experimental conditions given to a group of 60 subjects. The paper discusses the main results of this effort and their implications to theory and application in human performance.

  3. Pilot workload evaluated with subjective and physiological measures

    NARCIS (Netherlands)

    Veltman, J.A.; Gaillard, A.W.K.

    1993-01-01

    The aim of the present study is to validate different measures for mental workload. Ten aspirant fighter jet pilots flew several scenarios in a flight simulator. The scenarios were divided into segments with different levels of task load. During the flight, heart rate, respiration and blood pressure

  4. Workload: Measurement and Management

    Science.gov (United States)

    Gore, Brian Francis; Casner, Stephen

    2010-01-01

    Poster: The workload research project has as its task to survey the available literature on: (1) workload measurement techniques; and (2) the effects of workload on operator performance. The first set of findings provides practitioners with a collection of simple-to-use workload measurement techniques along with characterizations of the kinds of tasks each technique has been shown reliably address. This allows design practitioners to select and use the most appropriate techniques for the task(s) at hand. The second set of findings provides practitioners with the guidance they need to design for appropriate kinds and amounts of workload across all tasks for which the operator is responsible. This guidance helps practitioners design systems and procedures that ensure appropriate levels of engagement across all tasks, and avoid designs and procedures that result in operator boredom, complacency, loss of awareness, undue levels of stress, or skill atrophy that can result from workload that distracts operators from the tasks they perform and monitor, workload levels that are too low, too high, or too consistent or predictable. Only those articles that were peer reviewed, long standing and generally accepted in the field, and applicable to a relevant range of conditions in a select domain of interest, in analogous "extreme" environments to those in space were included. In addition, all articles were reviewed and evaluated on uni-dimensional and multi-dimensional considerations. Casner & Gore also examined the notion of thresholds and the conditions that may benefit mostly from the various methodological approaches. Other considerations included whether the tools would be suitable for guiding a requirement-related and design-related question. An initial review of over 225 articles was conducted and entered into an EndNote database. The reference list included a range of conditions in the domain of interest (subjective/objective measures), the seminal works in workload, as

  5. Assessment of pilot workload - Converging measures from performance based, subjective and psychophysiological techniques

    Science.gov (United States)

    Kramer, Arthur F.; Sirevaag, Erik J.; Braune, Rolf

    1986-01-01

    This study explores the relationship between the P300 component of the event-related brain potential (ERP) and the processing demands of a complex real-world task. Seven male volunteers enrolled in an Instrument Flight Rule (IFR) aviation course flew a series of missions in a single engine fixed-based simulator. In dual task conditions subjects were also required to discriminate between two tones differing in frequency. ERPs time-locked to the tones, subjective effort ratings and overt performance measures were collected during two 45 min flights differing in difficulty (manipulated by varying both atmospheric conditions and instrument reliability). The more difficult flight was associated with poorer performance, increased subjective effort ratings, and smaller secondary task P300s. Within each flight, P300 amplitude was negatively correlated with deviations from command headings indicating that P300 amplitude was a sensitive workload metric both between and within the flight missions.

  6. Defining the subjective experience of workload

    Science.gov (United States)

    Hart, S. G.; Childress, M. E.; Bortolussi, M.

    1981-01-01

    Flight scenarios that represent different types and levels of pilot workload are needed in order to conduct research about, and develop measures of, pilot workload. In order to be useful, however, the workload associated with such scenarios and the component tasks must be determined independently. An initial study designed to provide such information was conducted by asking a panel of general aviation pilots to evaluate flight-related tasks for the overall, perceptual, physical, and cognitive workload they impose. These ratings will provide the nucleus for a data base of flight-related primary tasks that have been independently rated for workload to use in workload assessment research.

  7. The psychophysics of workload - A second look at the relationship between subjective measures and performance

    Science.gov (United States)

    Gopher, D.; Chillag, N.; Arzi, N.

    1985-01-01

    Load estimates based upon subjective and performance indices were compared for subjects performing size matching and letter typing tasks under 6 levels of priorities, in single and dual task conditions. Each half of the group used a different task as reference in their subjective judgement. The results are interpreted to indicate that subjective measures are especially sensitive to voluntary allocation of attention and to the load on working memory. Association with performance is expected whenever these two factors are main determinants of performance efficiency, otherwise the two are likely to dissociate.

  8. Measurement of Workload: Physics, Psychophysics, and Metaphysics

    Science.gov (United States)

    Gopher, D.

    1984-01-01

    The present paper reviews the results of two experiments in which workload analysis was conducted based upon performance measures, brain evoked potentials and magnitude estimations of subjective load. The three types of measures were jointly applied to the description of the behavior of subjects in a wide battery of experimental tasks. Data analysis shows both instances of association and dissociation between types of measures. A general conceptual framework and methodological guidelines are proposed to account for these findings.

  9. Perceived Time as a Measure of Mental Workload

    DEFF Research Database (Denmark)

    Hertzum, Morten; Holmegaard, Kristin Due

    2013-01-01

    The mental workload imposed by systems is important to their operation and usability. Consequently, researchers and practitioners need reliable, valid, and easy-to-administer methods for measuring mental workload. The ratio of perceived time to clock time appears to be such a method, yet mental...... is a performance-related rather than task-related dimension of mental workload. We find a higher perceived time ratio for timed than untimed tasks. According to subjective workload ratings and pupil-diameter measurements the timed tasks impose higher mental workload. This finding contradicts the prospective...... the perceived time ratio and mental workload is reversed for task success compared to time constraints. We discuss implications for the use of perceived time as a measure of mental workload....

  10. Individual differences and subjective workload assessment - Comparing pilots to nonpilots

    Science.gov (United States)

    Vidulich, Michael A.; Pandit, Parimal

    1987-01-01

    Results by two groups of subjects, pilots and nonpilots, for two subjective workload assessment techniques (the SWAT and NASA-TLX tests) intended to evaluate individual differences in the perception and reporting of subjective workload are compared with results obtained for several traditional personality tests. The personality tests were found to discriminate between the groups while the workload tests did not. It is concluded that although the workload tests may provide useful information with respect to the interaction between tasks and personality, they are not effective as pure tests of individual differences.

  11. The effect of varying task difficulty on subjective workload

    Science.gov (United States)

    Yeh, Y.-Y.; Wickens, C. D.; Hart, S. G.

    1985-01-01

    The effect of different difficulty distribution patterns on subjective workload, and the presence of a primacy/recency effect in subjective ratings are examined. Eight subjects performed the perceptual central processing required for response selection and manual target acquisition for response execution. The reaction time, movement time, and the percent of correct pattern matching and arithmetic equations are analyzed. The data reveal that subjective rating is unaffected by different task difficulty and no primacy/recency effects are observed in subjective ratings. It is concluded that subjective workload reflects the experience of an ongoing integration process.

  12. A multilevel approach to relating subjective workload to performance after shifts in task demand.

    Science.gov (United States)

    Mracek, Derek L; Arsenault, Matthew L; Day, Eric Anthony; Hardy, Jay H; Terry, Robert A

    2014-12-01

    The aim of this laboratory experiment was to demonstrate how taking a longitudinal, multilevel approach can be used to examine the dynamic relationship between subjective workload and performance over a given period of activity involving shifts in task demand. Subjective workload and conditions of the performance environment are oftentimes examined via cross-sectional designs without distinguishing within-from between-person effects. Given the dynamic nature of performance phenomena, multilevel designs coupled with manipulations of task demand shifts are needed to better model the dynamic relationships between state and trait components of subjective workload and performance. With a sample of 75 college students and a computer game representing a complex decision-making environment, increases and decreases in task demand were counterbalanced and subjective workload and performance were measured concurrently in regular intervals within performance episodes. Data were analyzed using hierarchical linear modeling. Both between- and especially within-person effects were dynamic. Nevertheless, at both levels of analysis, higher subjective workload reflected performance problems, especially more downstream from increases in task demand. As a function of cognitive-energetic processes, shifts in task demand are associated with changes in how subjective workload is related to performance over a given period of activity. Multilevel, longitudinal approaches are useful for distinguishing and examining the dynamic relationships between state and trait components of subjective workload and performance. The findings of this research help to improve the understanding of how a sequence of demands can exceed a performer's capability to respond to further demands.

  13. Subjective Workload Assessment Technique (SWAT): A User’s Guide

    Science.gov (United States)

    1989-07-01

    The effects of supervisor experience and the presence of a shift technical advisor on the performance of two-man crews in a nuclear power plant...et de Recherches de Medecine Acrospatiale, Laboratoire d’Etudes Medicophysiologiques 16/330). S 110 Potter, S. S., 1986, Subjective workload assessment

  14. Workload Measurement in Human Autonomy Teaming: How and Why?

    Science.gov (United States)

    Shively, Jay

    2016-01-01

    This is an invited talk on autonomy and workload for an AFRL Blue Sky workshop sponsored by the Florida Institute for Human Machine Studies. The presentation reviews various metrics of workload and how to move forward with measuring workload in a human-autonomy teaming environment.

  15. Cardiac-Activity Measures for Assessing Airport Ramp-Tower Controller's Workload

    Science.gov (United States)

    Hayashi, Miwa; Dulchinos, Victoria

    2016-01-01

    Heart rate (HR) and heart rate variability (HRV) potentially offer objective, continuous, and non-intrusive measures of human-operators mental workload. Such measurement capability is attractive for workload assessment in complex laboratory simulations or safety-critical field testing. The present study compares mean HR and HRV data with self-reported subjective workload ratings collected during a high-fidelity human-in-the-loop simulation of airport ramp traffic control operations, which involve complex cognitive and coordination tasks. Mean HR was found to be weakly sensitive to the workload ratings, while HRV was not sensitive or even contradictory to the assumptions. Until more knowledge on stress response mechanisms of the autonomic nervous system is obtained, it is recommended that these cardiac-activity measures be used with other workload assessment tools, such as subjective measures.

  16. MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX)

    Science.gov (United States)

    Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M.

    2012-01-01

    High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses’ workload using a subjective rating instrument: the NASA TLX. We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses’ workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs. Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs. PMID:22773941

  17. Real-time measurement of mental workload: A feasibility study

    Science.gov (United States)

    Kramer, Arthur; Humphrey, Darryl; Sirevaag, Erik; Mecklinger, Axel

    1990-01-01

    The primary goal of the study was to explore the utility of event-related brain potentials (ERP) as real-time measures of workload. To this end, subjects performed two different tasks both separately and together. One task required that subjects monitor a bank of constantly changing gauges and detect critical deviations. Difficulty was varied by changing the predictability of the gauges. The second task was mental arithmetic. Difficulty was varied by requiring subjects to perform operations on either two or three columns of numbers. Two conditions that could easily be distinguished on the basis of performance measures were selected for the real-time evaluation of ERPs. A bootstrapping approach was adopted in which one thousand samples of n trials (n = 1, 3, 5 ...65) were classified using several measures of P300 and Slow Wave amplitude. Classification accuracies of 85 percent were achieved with 25 trials. Results are discussed in terms of potential enhancements for real-time recording.

  18. Measuring the nursing workload per shift in the ICU

    NARCIS (Netherlands)

    Debergh, Dieter P.; Myny, Dries; Van Herzeele, Isabelle; Van Maele, Georges; Miranda, Dinis Reis; Colardyn, Francis

    In the intensive care unit (ICU) different strategies and workload measurement tools exist to indicate the number of nurses needed. The gathered information is always focused on manpower needed per 24 h. However, a day consists of several shifts, which may be unequal in nursing workload. The aim of

  19. Mental Workload Measurement in Operational Aircraft Systems: Two Promising Approaches,

    Science.gov (United States)

    Mental workload (MWL) is becoming a useful construct for the design of complex man-machine systems because it provides a framework to include many...involves very little action but high degrees of mental activity. Although we have employed task-analytic workload measures for many years

  20. A Multiple Processing Resource Explanation of the Subjective Dimensions of Operator Workload.

    Science.gov (United States)

    1984-02-01

    Arabie, P. (1979). Auditory versus phonetic accounts of observed confusions between consonant phonemes. Journal of the Acoustal Society of America, 66, 46...similarity. Scaling and clustering analyses of the similarity data produced subjective dimensions/ clusters of workload that were explained in terms of...by subjects and rated according to workload similarity. Scaling and clustering analyses of the similarity data produced subjective dimensions/ clusters

  1. Mental workload measurement in operator control room using NASA-TLX

    Science.gov (United States)

    Sugarindra, M.; Suryoputro, M. R.; Permana, A. I.

    2017-12-01

    The workload, encountered a combination of physical workload and mental workload, is a consequence of the activities for workers. Central control room is one department in the oil processing company, employees tasked with monitoring the processing unit for 24 hours nonstop with a combination of 3 shifts in 8 hours. NASA-TLX (NASA Task Load Index) is one of the subjective mental workload measurement using six factors, namely the Mental demand (MD), Physical demand (PD), Temporal demand (TD), Performance (OP), Effort (EF), frustration levels (FR). Measurement of a subjective mental workload most widely used because it has a high degree of validity. Based on the calculation of the mental workload, there at 5 units (DTU, NPU, HTU, DIST and OPS) at the control chamber (94; 83.33; 94.67; 81, 33 and 94.67 respectively) that categorize as very high mental workload. The high level of mental workload on the operator in the Central Control Room is a requirement to have high accuracy, alertness and can make decisions quickly

  2. Multisubject "Learning" for Mental Workload Classification Using Concurrent EEG, fNIRS, and Physiological Measures.

    Science.gov (United States)

    Liu, Yichuan; Ayaz, Hasan; Shewokis, Patricia A

    2017-01-01

    An accurate measure of mental workload level has diverse neuroergonomic applications ranging from brain computer interfacing to improving the efficiency of human operators. In this study, we integrated electroencephalogram (EEG), functional near-infrared spectroscopy (fNIRS), and physiological measures for the classification of three workload levels in an n-back working memory task. A significantly better than chance level classification was achieved by EEG-alone, fNIRS-alone, physiological alone, and EEG+fNIRS based approaches. The results confirmed our previous finding that integrating EEG and fNIRS significantly improved workload classification compared to using EEG-alone or fNIRS-alone. The inclusion of physiological measures, however, does not significantly improves EEG-based or fNIRS-based workload classification. A major limitation of currently available mental workload assessment approaches is the requirement to record lengthy calibration data from the target subject to train workload classifiers. We show that by learning from the data of other subjects, workload classification accuracy can be improved especially when the amount of data from the target subject is small.

  3. Assessment of subjective workload in an anaesthesia simulator environment: reliability and validity.

    Science.gov (United States)

    Schulz, Christian M; Skrzypczak, Matthias; Schneider, Erich; Hapfelmeier, Alexander; Martin, Jan; Kochs, Eberhard F; Schneider, Gerhard

    2011-07-01

    For the subjective assessment of workload, Borg's Rating of Perceived Exertion (RPE) scale is a global measure of perceived workload during anaesthesia induction, maintenance and emergence in the real workplace. In the present study, validity and reliability of the RPE scale were analysed for a full-scale simulator environment using scenarios of induction of general anaesthesia with and without critical incidents. Seventeen anaesthetists (professional experience 1-30 years) participated in this randomised cross-over trial. Each participant rated their workload using the RPE scale after three different simulator sessions. No critical incident was simulated in the 1st session. In a randomised order, workload was increased by simulation of a critical incident in the 2nd or 3rd session. For the analysis of validity and reliability, univariate and multivariate regression analysis and the concordance correlation coefficient were used. RPE scores were significantly increased after managing a simulated critical incident [13.0, 95% confidence interval (CI) 11.6-14.5] compared to normal anaesthesia induction (9.4, 95% CI 8.2-10.6; P Reliability was moderate (concordance correlation coefficient = 0.55; 95% CI 0.13-0.80) for uneventful sessions. RPE scores were significantly increased after critical incidents during simulated anaesthesia induction and indicate good construct validity. Reliability may be impaired by the fact that the first session was announced to be without a critical incident. The RPE scale is easy to administer and a valid tool for subjective workload assessment in simulator settings. Reliability is moderate.

  4. Subjective health complaints and self-rated health: are expectancies more important than socioeconomic status and workload?

    Science.gov (United States)

    Ree, Eline; Odeen, Magnus; Eriksen, Hege R; Indahl, Aage; Ihlebæk, Camilla; Hetland, Jørn; Harris, Anette

    2014-06-01

    The associations between socioeconomic status (SES), physical and psychosocial workload and health are well documented. According to The Cognitive Activation Theory of Stress (CATS), learned response outcome expectancies (coping, helplessness, and hopelessness) are also important contributors to health. This is in part as independent factors for health, but coping may also function as a buffer against the impact different demands have on health. The purpose of this study was to investigate the relative effect of SES (as measured by level of education), physical workload, and response outcome expectancies on subjective health complaints (SHC) and self-rated health, and if response outcome expectancies mediate the effects of education and physical workload on SHC and self-rated health. A survey was carried out among 1,746 Norwegian municipal employees (mean age 44.2, 81 % females). Structural Equation Models with SHC and self-rated health as outcomes were conducted. Education, physical workload, and response outcome expectancies, were the independent 28 variables in the model. Helplessness/hopelessness had a stronger direct effect on self-rated health and SHC than education and physical workload, for both men and women. Helplessness/hopelessness fully mediated the effect of physical workload on SHC for men (0.121), and mediated 30 % of a total effect of 0.247 for women. For women, education had a small but significant indirect effect through helplessness/hopelessness on self-rated health (0.040) and SHC (-0.040), but no direct effects were found. For men, there was no effect of education on SHC, and only a direct effect on self-rated health (0.134). The results indicated that helplessness/hopelessness is more important for SHC and health than well-established measures on SES such as years of education and perceived physical workload in this sample. Helplessness/hopelessness seems to function as a mechanism between physical workload and health.

  5. Neonatal nursing workload – can it be measured?

    Directory of Open Access Journals (Sweden)

    J. M. van den Heever

    1995-05-01

    Full Text Available Continuing pressure an tertiary hospitals 10 reduce expenses has inevitably meant a demand to reduce nursing staff. This intensified the need to ensure that staffing allocation is appropriate. A method to calculate staffing needs based measurement of neonatal workload is explored.

  6. Development of a nursing workload measurement instrument in burn care

    NARCIS (Netherlands)

    Jong, A.E.; Leeman, J.; Middelkoop, E.

    2009-01-01

    Existing workload measurement instruments fail to represent specific nursing activities in a setting where patients are characterized by a diversity of cause, location, extent and depth of burns, of age and of history. They also do not include educational levels and appropriate time standards. The

  7. gLite Workload Management System Performance Measurements

    CERN Document Server

    Svraka, N; Belic, A; Bogojevic, A R

    2006-01-01

    In this paper an introduction to the gLite Grid middleware and one of its most important components, Workload Management System (WMS), responsible for management of user jobs is given.Useful performance metrics of gLite WMS are defined from a Grid application point of view, and preliminary results of performance measurements are presented and briefly analyzed.

  8. Measuring Workload Weak Resilience Signals at a Rail Control Post

    NARCIS (Netherlands)

    Siegel, A.W.; Schraagen, J.M.C.

    2014-01-01

    OCCUPATIONAL APPLICATIONS This article describes an observational study at a rail control post to measure workload weak resilience signals. A weak resilience signal indicates a possible degradation of a system's resilience, which is defined as the ability of a complex socio-technical system to cope

  9. Multisubject “Learning” for Mental Workload Classification Using Concurrent EEG, fNIRS, and Physiological Measures

    Science.gov (United States)

    Liu, Yichuan; Ayaz, Hasan; Shewokis, Patricia A.

    2017-01-01

    An accurate measure of mental workload level has diverse neuroergonomic applications ranging from brain computer interfacing to improving the efficiency of human operators. In this study, we integrated electroencephalogram (EEG), functional near-infrared spectroscopy (fNIRS), and physiological measures for the classification of three workload levels in an n-back working memory task. A significantly better than chance level classification was achieved by EEG-alone, fNIRS-alone, physiological alone, and EEG+fNIRS based approaches. The results confirmed our previous finding that integrating EEG and fNIRS significantly improved workload classification compared to using EEG-alone or fNIRS-alone. The inclusion of physiological measures, however, does not significantly improves EEG-based or fNIRS-based workload classification. A major limitation of currently available mental workload assessment approaches is the requirement to record lengthy calibration data from the target subject to train workload classifiers. We show that by learning from the data of other subjects, workload classification accuracy can be improved especially when the amount of data from the target subject is small. PMID:28798675

  10. Multisubject “Learning” for Mental Workload Classification Using Concurrent EEG, fNIRS, and Physiological Measures

    Directory of Open Access Journals (Sweden)

    Yichuan Liu

    2017-07-01

    Full Text Available An accurate measure of mental workload level has diverse neuroergonomic applications ranging from brain computer interfacing to improving the efficiency of human operators. In this study, we integrated electroencephalogram (EEG, functional near-infrared spectroscopy (fNIRS, and physiological measures for the classification of three workload levels in an n-back working memory task. A significantly better than chance level classification was achieved by EEG-alone, fNIRS-alone, physiological alone, and EEG+fNIRS based approaches. The results confirmed our previous finding that integrating EEG and fNIRS significantly improved workload classification compared to using EEG-alone or fNIRS-alone. The inclusion of physiological measures, however, does not significantly improves EEG-based or fNIRS-based workload classification. A major limitation of currently available mental workload assessment approaches is the requirement to record lengthy calibration data from the target subject to train workload classifiers. We show that by learning from the data of other subjects, workload classification accuracy can be improved especially when the amount of data from the target subject is small.

  11. Measurement of nurses' workload in an oncology outpatient clinic

    Directory of Open Access Journals (Sweden)

    Célia Alves de Souza

    2014-02-01

    Full Text Available The growing demand and the degree of patient care in oncological outpatient services, as well as the complexity of treatment have had an impact on the workload of nurses. This study aimed at measuring the workload and productivity of nurses in an oncological outpatient service. An observational study using a work sampling technique was conducted and included seven nurses working in an oncological outpatient service in the south-eastern region of Brazil. A total of 1,487 intervention or activity samples were obtained. Nurses used 43.2% of their time on indirect care, 33.2% on direct care, 11.6% on associated activities, and 12% on personal activities. Their mean productivity was 88.0%. The findings showed that nurses in this service spend most of their time in indirect care activities. Moreover, the productivity index in this study was above that recommended in the literature.

  12. Subjective Cognitive Workload, Interactivity and Feedback in a Web-Based Writing Program

    Science.gov (United States)

    Emerson, Lisa; MacKay, Bruce R.

    2006-01-01

    This investigation compares and analyses the experiences and subjective cognitive workload of students undertaking a lesson on an aspect of micro-level writing skills in a web-based and paperbased version. Both versions of the lesson were based on the principles of interactive learning, specifically on a modified version of Chou's (2003) model.…

  13. Effects of Visual Communication Tool and Separable Status Display on Team Performance and Subjective Workload in Air Battle Management

    National Research Council Canada - National Science Library

    Schwartz, Daniel; Knott, Benjamin A; Galster, Scott M

    2008-01-01

    ... ambient cabin noise while performing several visual and manual tasks. The purpose of this study is to compare team performance and subjective workload on a simulated AWACS scenario, for two conditions of communication...

  14. Mental workload measurement for emergency operating procedures in digital nuclear power plants.

    Science.gov (United States)

    Gao, Qin; Wang, Yang; Song, Fei; Li, Zhizhong; Dong, Xiaolu

    2013-01-01

    Mental workload is a major consideration for the design of emergency operation procedures (EOPs) in nuclear power plants. Continuous and objective measures are desired. This paper compares seven mental workload measurement methods (pupil size, blink rate, blink duration, heart rate variability, parasympathetic/sympathetic ratio, total power and (Goals, Operations, Methods, and Section Rules)-(Keystroke Level Model) GOMS-KLM-based workload index) with regard to sensitivity, validity and intrusiveness. Eighteen participants performed two computerised EOPs of different complexity levels, and mental workload measures were collected during the experiment. The results show that the blink rate is sensitive to both the difference in the overall task complexity and changes in peak complexity within EOPs, that the error rate is sensitive to the level of arousal and correlate to the step error rate and that blink duration increases over the task period in both low and high complexity EOPs. Cardiac measures were able to distinguish tasks with different overall complexity. The intrusiveness of the physiological instruments is acceptable. Finally, the six physiological measures were integrated using group method of data handling to predict perceived overall mental workload. The study compared seven measures for evaluating the mental workload with emergency operation procedure in nuclear power plants. An experiment with simulated procedures was carried out, and the results show that eye response measures are useful for assessing temporal changes of workload whereas cardiac measures are useful for evaluating the overall workload.

  15. Impact of automation: Measurement of performance, workload and behaviour in a complex control environment.

    Science.gov (United States)

    Balfe, Nora; Sharples, Sarah; Wilson, John R

    2015-03-01

    This paper describes an experiment that was undertaken to compare three levels of automation in rail signalling; a high level in which an automated agent set routes for trains using timetable information, a medium level in which trains were routed along pre-defined paths, and a low level where the operator (signaller) was responsible for the movement of all trains. These levels are described in terms of a Rail Automation Model based on previous automation theory (Parasuraman et al., 2000). Performance, subjective workload, and signaller activity were measured for each level of automation running under both normal operating conditions and abnormal, or disrupted, conditions. The results indicate that perceived workload, during both normal and disrupted phases of the experiment, decreased as the level of automation increased and performance was most consistent (i.e. showed the least variation between participants) with the highest level of automation. The results give a strong case in favour of automation, particularly in terms of demonstrating the potential for automation to reduce workload, but also suggest much benefit can achieved from a mid-level of automation potentially at a lower cost and complexity. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. The Peripheral Detection Task (PDT) : On-line measurement of driver cognitive workload and selective attention

    NARCIS (Netherlands)

    Horst, A.R.A. van der; Martens, M.H.

    2010-01-01

    Peaks in workload while driving might have immediate safety implications. The Peripheral Detection Task (PDT) has shown to be a sensitive objective workload measure. Drivers have to respond to the onset of a peripherally presented simple visual stimulus (red square or LED) by pressing a finger

  17. The effect of match standard and referee experience on the objective and subjective match workload of English Premier League referees.

    Science.gov (United States)

    Weston, M; Bird, S; Helsen, W; Nevill, A; Castagna, C

    2006-06-01

    The aim of the present study was to examine the effect of match standard and referee experience on the objective and subjective workload of referees during English Premier League and Football League soccer matches. We also examined the relationship between heart rate (HR) and ratings of perceived exertion (RPE) for assessing match intensity in soccer referees. Heart rate responses were recorded using short-range telemetry and RPE scores were collected using a 10-point scale. Analysis revealed a significant relationship between mean match HR and match RPE scores (r=0.485, pFootball League 81.5+/-2.2%HRmax, pFootball League 6.9+/-0.8, pReferee experience had no effect on match HR and RPE responses to Premier League and Football League matches. The results of the present study demonstrate the validity of using HR and RPE as a measure of global match intensity in soccer referees. Referee experience had no effect on the referees' objective and subjective match workload assessments, whereas match intensity was correlated to competition standard. These findings have implications for fitness preparation and evaluation in soccer referees. When progressing to a higher level of competition, referees should ensure that appropriate levels of fitness are developed in order to enable them to cope with an increase in physical match demands.

  18. A closed-loop causal model of workload based on a comparison of fuzzy and crisp measurements techniques

    Science.gov (United States)

    Moray, Neville; King, Barbara; Turksen, Burhan; Waterton, Keith

    1987-01-01

    Fuzzy and crisp measurements of workload are compared for a tracking task that varied in bandwidth and order of control. Fuzzy measures are as powerful as crisp measures, and can under certain conditions give extra insights into workload causality. Both methods suggest that workload arises in a system in which effort, performance, difficulty, and task variables are linked in a closed loop. Marked individual differences were found. Future work on the fuzzy measurement of workload is justified.

  19. Measuring Mental Workload with EEG+fNIRS.

    Science.gov (United States)

    Aghajani, Haleh; Garbey, Marc; Omurtag, Ahmet

    2017-01-01

    We studied the capability of a Hybrid functional neuroimaging technique to quantify human mental workload (MWL). We have used electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) as imaging modalities with 17 healthy subjects performing the letter n-back task, a standard experimental paradigm related to working memory (WM). The level of MWL was parametrically changed by variation of n from 0 to 3. Nineteen EEG channels were covering the whole-head and 19 fNIRS channels were located on the forehead to cover the most dominant brain region involved in WM. Grand block averaging of recorded signals revealed specific behaviors of oxygenated-hemoglobin level during changes in the level of MWL. A machine learning approach has been utilized for detection of the level of MWL. We extracted different features from EEG, fNIRS, and EEG+fNIRS signals as the biomarkers of MWL and fed them to a linear support vector machine (SVM) as train and test sets. These features were selected based on their sensitivity to the changes in the level of MWL according to the literature. We introduced a new category of features within fNIRS and EEG+fNIRS systems. In addition, the performance level of each feature category was systematically assessed. We also assessed the effect of number of features and window size in classification performance. SVM classifier used in order to discriminate between different combinations of cognitive states from binary- and multi-class states. In addition to the cross-validated performance level of the classifier other metrics such as sensitivity, specificity, and predictive values were calculated for a comprehensive assessment of the classification system. The Hybrid (EEG+fNIRS) system had an accuracy that was significantly higher than that of either EEG or fNIRS. Our results suggest that EEG+fNIRS features combined with a classifier are capable of robustly discriminating among various levels of MWL. Results suggest that EEG+fNIRS should

  20. Combining and comparing EEG, peripheral physiology and eye-related measures for the assessment of mental workload

    Directory of Open Access Journals (Sweden)

    Maarten Andreas Hogervorst

    2014-10-01

    Full Text Available While studies exist that compare different physiological variables with respect to their association with mental workload, it is still largely unclear which variables supply the best information about momentary workload of an individual and what is the benefit of combining them. We investigated workload using the n-back task, controlling for body movements and visual input. We recorded EEG, skin conductance, respiration, ECG, pupil size and eye blinks of 14 subjects. Various variables were extracted from these recordings and used as features in individually tuned classification models. Online classification was simulated by using the first part of the data as training set and the last part of the data for testing the models. The results indicate that EEG performs best, followed by eye related measures and peripheral physiology. Combining variables from different sensors did not significantly improve workload assessment over the best performing sensor alone. Best classification accuracy, a little over 90% (SD 4%, was reached for distinguishing between high and low workload on the basis of 2 minute segments of EEG and eye related variables. A similar and not significantly different performance of 86% (SD 5% was reached using only EEG from single electrode location Pz.

  1. Breakfast high in whey protein or carbohydrates improves coping with workload in healthy subjects.

    Science.gov (United States)

    Sihvola, Nora; Korpela, Riitta; Henelius, Andreas; Holm, Anu; Huotilainen, Minna; Müller, Kiti; Poussa, Tuija; Pettersson, Kati; Turpeinen, Anu; Peuhkuri, Katri

    2013-11-14

    Dietary components may affect brain function and influence behaviour by inducing the synthesis of neurotransmitters. The aim of the present study was to examine the influence of consumption of a whey protein-containing breakfast drink v. a carbohydrate drink v. control on subjective and physiological responses to mental workload in simulated work. In a randomised cross-over design, ten healthy subjects (seven women, median age 26 years, median BMI 23 kg/m(2)) participated in a single-blinded, placebo-controlled study. The subjects performed demanding work-like tasks after having a breakfast drink high in protein (HP) or high in carbohydrate (HC) or a control drink on separate sessions. Subjective states were assessed using the NASA Task Load Index (NASA-TLX), the Karolinska sleepiness scale (KSS) and the modified Profile of Mood States. Heart rate was recorded during task performance. The ratio of plasma tryptophan (Trp) to the sum of the other large neutral amino acids (LNAA) and salivary cortisol were also analysed. The plasma Trp:LNAA ratio was 30 % higher after the test drinks HP (median 0·13 (μmol/l)/(μmol/l)) and HC (median 0·13 (μmol/l)/(μmol/l)) than after the control drink (median 0·10 (μmol/l)/(μmol/l)). The increase in heart rate was smaller after the HP (median 2·7 beats/min) and HC (median 1·9 beats/min) drinks when compared with the control drink (median 7·2 beats/min) during task performance. Subjective sleepiness was reduced more after the HC drink (median KSS - 1·5) than after the control drink (median KSS - 0·5). There were no significant differences between the breakfast types in the NASA-TLX index, cortisol levels or task performance. We conclude that a breakfast drink high in whey protein or carbohydrates may improve coping with mental tasks in healthy subjects.

  2. Cognitive workload across the spectrum of cognitive impairments: A systematic review of physiological measures.

    Science.gov (United States)

    Ranchet, Maud; Morgan, John C; Akinwuntan, Abiodun E; Devos, Hannes

    2017-09-01

    Our objective was to identify the physiological measures that are sensitive to assessing cognitive workload across the spectrum of cognitive impairments. Three database searches were conducted: PubMed, PsychINFO, and Web of Science. Studies from the last decade that used physiological measures of cognitive workload in older adults (mean age >65 years-old) were reviewed. The cognitive workload of healthy older individuals was compared with the cognitive workload of younger adults, patients with mild cognitive impairment (MCI), and patients with Alzheimer's diseases (AD). The most common measures of cognitive workload included: electroencephalography, magnetoencephalography, functional magnetic resonance imaging, pupillometry, and heart rate variability. These physiological measures consistently showed greater cognitive workload in healthy older adults compared to younger adults when performing the same task. The same was observed in patients with MCI compared to healthy older adults. Behavioral performance declined when the available cognitive resources became insufficient to cope with the cognitive demands of a task, such as in AD. These findings may have implications for clinical practice and future cognitive interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Heart Rate Variability as a Measure of Airport Ramp-Traffic Controllers Workload

    Science.gov (United States)

    Hayashi, Miwa; Dulchinos, Victoria Lee

    2016-01-01

    Heart Rate Variability (HRV) has been reported to reflect the person's cognitive and emotional stress levels, and may offer an objective measure of human-operator's workload levels, which are recorded continuously and unobtrusively to the task performance. The present paper compares the HRV data collected during a human-in-the-loop simulation of airport ramp-traffic control operations with the controller participants' own verbal self-reporting ratings of their workload.

  4. Adapting workload improves the measurement of heart rate recovery.

    Science.gov (United States)

    Lamberts, R P; Maskell, S; Borresen, J; Lambert, M I

    2011-09-01

    Heart rate after a standardized test varies with a change in training status, possibly compromising the accuracy of measuring changes in heart rate recovery (HRR). The aim of this study was to determine if a change in the exercise intensity would result in a change in heart rate recovery and/or the accuracy of the heart rate recovery measurement. 31 subjects performed 4 submaximal running tests (HIMS). Based on the heart rate after the first HIMS, subjects either completed 4 identical HIMS (SAME (n=9)), 2 standard and 2 faster HIMS (FASTER (n=10)) or 2 standard and 2 slower HIMS (SLOWER (n=12)). Although no changes in heart rate recovery were found when the HIMS protocol was adapted, lower coefficients of variation (CV) and typical errors of measurement (TEM) were found in the SLOWER (CV: 11 ± 7 to 5 ± 3% ( P=0.025)), TEM: 6 to 3 beats and FASTER group (CV: 11 ± 7 to 4 ± 3% ( P=0.048), TEM: 7 to 3 beats). To ensure the highest level of sensitivity in detecting meaningful changes in HRR over time, submaximal testing protocols should target exercise intensities ranging in-between 86-93% of heart rate maximum. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Time estimation as a secondary task to measure workload. [attention sharing effect on operator performance

    Science.gov (United States)

    Hart, S. G.

    1975-01-01

    Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.

  6. Nursing workload measurement scales in Intensive Care Units. Correlation between NAS and NEMS

    Directory of Open Access Journals (Sweden)

    Montserrat Martínez Lareo

    2011-11-01

    Full Text Available The high costs of intensive care and the importance of patient safety and quality of care highlight the need to develop instrument to measure, as precisely as possible, nursing workload and staffing levels in intensive care. To assess the ideal staff number, we need instruments to measure the real nursing workload. The aim of this research is to compare two nursing workload measurement scales in Intensive Care Units, the Nursing Activities Score (NAS and Nine Equivalents of Nurse Manpower Use Score (NEMS. We also want to assess the staffing needs of our ICU. A descriptive correlational study will be performed in a mixed medical ICU. The sample will be composed of of a minimum of 70 patients. Data regarding individual patients and unit global workload will be recorded, measured both with the NEMS and NAS scales. The required nursing staff will be calculated according to the measured workload. Nursing staffing needs using both scales will be calculated and compared to the actual staff. A descriptive analysis of the variables will be performed, and the existing correlation between both scales will be assessed using the Pearson correlation coefficient. A Student-t test will be performed to determine the differences between the calculated staffing requirements and the actual nursing staff. All data analyses will be done using a statistical software.

  7. Nursing workload and adherence to non-pharmacological measures in the prevention of ventilator-associated pneumonia. A pilot study.

    Science.gov (United States)

    Jam, R; Hernández, O; Mesquida, J; Turégano, C; Carrillo, E; Pedragosa, R; Gómez, V; Martí, L; Vallés, J; Delgado-Hito, P

    To analyse whether adherence to non-pharmacological measures in the prevention of ventilator-associated pneumonia (VAP) is associated with nursing workload. A prospective observational study performed in a single medical-surgical ICU. Nurses in charge of patients under ventilator support were assessed. knowledge questionnaire, application of non-pharmacological VAP prevention measures, and workload (Nine Equivalents of Nursing Manpower Use Score). Phases: 1) the nurses carried out a educational programme, consisting of 60-minute lectures on non-pharmacological measures for VAP prevention, and at the end completed a questionnaire knowledge; 2) observation period; 3) knowledge questionnaire. Among 67 ICU-staff nurses, 54 completed the educational programme and were observed. A total of 160 observations of 49 nurses were made. Adequate knowledge was confirmed in both the initial and final questionnaires. Application of preventive measures ranged from 11% for hand washing pre-aspiration to 97% for the use of a sterile aspiration probe. The Nine Equivalents of Nursing Manpower Use Score was 50±13. No significant differences were observed between the association of the nurses' knowledge and the application of preventive measures or between workload and the application of preventive measures. Nurses' knowledge of VAP prevention measures is not necessarily applied in daily practice. Failure to follow these measures is not subject to lack of knowledge or to increased workload, but presumably to contextual factors. Copyright © 2017 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Tracking workload in the emergency department.

    Science.gov (United States)

    Levin, Scott; France, Daniel J; Hemphill, Robin; Jones, Ian; Chen, Kong Y; Rickard, Dorsey; Makowski, Renee; Aronsky, Dominik

    2006-01-01

    The primary objective of this study was to create a methodology for measuring transient levels of physician workload in a live emergency department (ED) environment. Characterizing, defining, and measuring aspects of this interrupt-driven work environment represent the preliminary steps in addressing impending issues concerning ED overcrowding, efficiency, and patient and provider safety. A time-motion task analysis was conducted. Twenty emergency medicine (EM) physicians were observed for 180-min intervals in an ED of an academic medical center. Near continuous workload measures were developed and used to track changing workload levels in time. These measures were taken from subjective, objective, and physiological perspectives. The NASA-Task Load Index was administered to each physician after observational sessions to measure subjective workload. Physiological measurements were taken throughout the duration of the observation to measure stress response. Additional information concerning physicians' patient quantity and patient complexity was extracted from the ED information system. Graphical workload profiles were created by combining observational and subjective data with system state data. Methodologies behind the creation of workload profiles are discussed, the workload profiles are compared, and quantitative and qualitative analyses are conducted. Using human factors methods to measure workload in a setting such as the ED proves to be challenging but has relevant application in improving the efficiency and safety of EM. Techniques implemented in this research are applicable in managing ED staff and real-time monitoring of physician workload.

  9. Interaction between workload and training - Converging evidence from psychophysiology and performance measurement

    Science.gov (United States)

    Kramer, Arthur F.

    1986-01-01

    Traditionally, the domains of mental workload and training have been studied in isolation even though they share many common characteristics. The present paper integrates findings from psychophysiological and performance-based studies which address both of these issues. By augmenting traditional indices of skill acquisition such as RMS error scores, reaction times, and accuracy measures with psychophysiological measures such as the event-related brain potential, it is shown that workload effects can be assessed throughout the training process. More specifically, it is argued that the development of skill and the effects of workload on the human operator can be modeled within the framework of resource theories of attentional allocation. Also described is how converging evidence from psychophysiological and behavioral studies can be used to examine subtle changes in operator strategies during training.

  10. Measuring educational workload: a pilot study of paper-based and PDA tools.

    Science.gov (United States)

    Tallett, Susan; Lingard, Lorelei; Leslie, Karen; Pirie, Jonathan; Jefferies, Ann; Spero, Lawrence; Schneider, Rayfel; Hilliard, Robert; Rosenfield, Jay; Hellmann, Jonathan; Mian, Marcellina; Hurley, Jennifer

    2008-01-01

    Teaching is an important professional role for most faculty members in academic health sciences centres. Careful delineation of educational workload is needed to foster and reward teaching efforts, and to facilitate equitable allocation of resources. To promote recognition in teaching and facilitate equitable resource allocation, we developed, piloted, and qualitatively assessed a tool for delineating the educational workload of pediatric faculty in an academic health sciences centre. A prototype educational workload measurement tool was developed. Between 2002 and 2004, three successive phases of pilot implementation were conducted to (1) assess the face validity of the tool, (2) assess its feasibility, and (3) develop and assess the feasibility of a PDA (Personal Digital Assistant) version. Participants were interviewed regarding strengths, weaknesses, and barriers to completion. Data were analyzed for recurrent themes. Faculty found that the tool was usable and represented a broad range of educational activities. The PDA format was easier to use and better received. Technical support would be imperative for long-term implementation. The greatest barriers to implementation were skepticism about the purpose of the tool and concerns that it would promote quantity over quality of teaching. We developed a usable tool to capture data on the diverse educational workload of pediatric faculty. PDA technology can be used to facilitate collection of workload data. Faculty skepticism is an important barrier that should be addressed in future work.

  11. Measuring Mental Workload with EEG+fNIRS

    National Research Council Canada - National Science Library

    Haleh Aghajani; Marc Garbey; Ahmet Omurtag

    2017-01-01

    ...). We have used electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) as imaging modalities with 17 healthy subjects performing the letter n-back task, a standard experimental paradigm related to working memory (WM...

  12. Nursing workload: a concept analysis.

    Science.gov (United States)

    Alghamdi, Mohammed G

    2016-05-01

    The aim of the present study was to develop a comprehensive understanding of the concept 'workload' within the nursing profession in order to arrive at a clear definition of nursing workload based on the evidence in existing literature. Nursing workload is a common term used in the health literature, but often without specification of its exact meaning. Concept clarification is needed to delineate the meaning of the term 'nursing workload'. A concept analysis was conducted using Walker and Avant's method to clarify the defining attributes of nursing workload. As the subject matter was nursing focused, only one database was searched, the Cumulative Index for Nursing and Allied Health Literature (CINAHL). Articles that did not use 'workload' in the title or abstract were excluded. A model case, contrary case, related case and empirical referents were constructed to clarify the concept and to demonstrate how the workload is captured by the main attributes. The attributes of nursing workload found in the literature fall into five main categories: the amount of nursing time; the level of nursing competency; the weight of direct patient care; the amount of physical exertion; and complexity of care. The attributes were organised according to the leading antecedents, which were identified as the patient, nurse and health institution. Nurse managers need to address the workload issues with regard to the real nature of nursing work; this could increase nurses' productivity, nurses' satisfaction, turnover, work stress and provide sufficient staffing to patient care needs. The concept analysis demonstrated clearly the complexity of the concept and its implications for practice and research. It is believed that the current concept analysis will help to provide a better understanding of nursing workload and contribute towards the standardisation of the nursing workload and the development of a valid and reliable measurement system. © 2016 John Wiley & Sons Ltd.

  13. Subjective responses of mental workload during real time driving: A pilot field study

    Science.gov (United States)

    Rahman, N. I. A.; Dawal, S. Z. M.; Yusoff, N.

    2017-06-01

    This study evaluated drivers’ mental workload in real time driving to identify the driving situation’s complexity influences in an attempt to further design on a complete experimental study. Three driving settings were prepared: Session A (simple situation); Session B (moderately complex situation); Session C (very complex situation). To determine the mental workload, the NASA-Task Load Index (TLX) was administered to four drivers after each experimental driving session. The results showed that the Own Performance (OP) was the highest for session A (highway), while Physical Demand (PD) recorded the highest mean workload score across the session B (rural road) and C (city road). Based on the overall results of the study, it can be concluded that the highway is less demanding compared to rural and city road. It can be highlighted in this study that in the rural and city road driving situation, the timing must be set correctly to assure the relevant traffic density. Thus, the sensitivity of the timing must be considered in the future experiment. A larger number of experience drivers must be used in evaluating the driving situations to provide results that can be used to draw more realistic experiments and conclusions.

  14. Assessing the adequacy of workload measurement tools using a quality-based methodology.

    Science.gov (United States)

    Gil, Maria Fuensanta Hellín; Montesinos, Maria José López; Llor, Ana Myriam Seva; Bas, Maria Pilar Ferrer; Soler, Maria Loreto Maciá

    2017-01-01

    determine which tool (NEMS and NAS) is most suitable for use in intensive care units using a quality-based methodology. after identifying the opportunity for improvement "Inadequacy of the NEMS for determining nursing workload in the intensive care unit (ICU)", we assessed the NEMS and the NAS, as a proposed improvement to the NEMS, using quality improvement cycles methodology based on the following criteria: measurement of daily nursing workload on a daily and shift basis; the tool encompasses all nursing activities undertaken in the ICU; and workload assessed per patient and unit. there was no significant difference in level of compliance for the NEMS (67%). The comparison NEMS-NAS showed that there was a statistically significant improvement for all criteria except criterion 1. The NEMS only assesses criterion 1 (64.22%); while the NAS assessed all four criteria, obtaining a compliance rate of 64.74% for criteria 1, 2, and 4, and 100% for criterion 3. the NAS is more suitable for measuring nursing workload in UCIs.

  15. Nursing and knowledge work: issues regarding workload measurement and the informatics nurse specialist.

    Science.gov (United States)

    Windsor, Jason

    2006-01-01

    The profession of nursing has been faced with questions concerning workload measurement for decades, and those concerns continue to be relevant today. Traditionally, nursing has turned to time-motion studies to study this, but there is a debate about how relevant time-motion studies are to the profession of nursing when it is viewed as knowledge work. Healthcare workers, including the nursing profession, may be the single biggest group of knowledge workers. Knowledge workers today represent a significantly different workforce than are the workers of the past. Informatics, as a specialty, is relatively new to the nursing profession and continually evolving. As more nurses enter informatics and function as informatics nurse specialists, they will continue to be in the group of knowledge workers whose observable input and output is difficult to measure. Today's healthcare leaders, managers, and administrators need to identify an appropriate method of workload measurement for knowledge workers.

  16. An Unobtrusive System to Measure, Assess, and Predict Cognitive Workload in Real-World Environments

    Science.gov (United States)

    Bracken, Bethany K.; Palmon, Noa; Elkin-Frankston, Seth; Irvin, Scott; Jenkins, Michael; Farry, Mike

    2017-01-01

    Across many careers, individuals face alternating periods of high and low attention and cognitive workload, which can result in impaired cognitive functioning and can be detrimental to job performance. For example, some professions (e.g., fire fighters, emergency medical personnel, doctors and nurses working in an emergency room, pilots) require long periods of low workload (boredom), followed by sudden, high-tempo operations during which they may be required to respond to an emergency and perform at peak cognitive levels. Conversely, other professions (e.g., air traffic controllers, market investors in financial industries, analysts) require long periods of high workload and multitasking during which the addition of just one more task results in cognitive overload resulting in mistakes. An unobtrusive system to measure, assess, and predict cognitive workload could warn individuals, their teammates, or their supervisors when steps should be taken to augment cognitive readiness. In this talk I will describe an approach to this problem that we have found to be successful across work domains including: (1) a suite of unobtrusive, field-ready neurophysiological, physiological, and behavioral sensors that are chosen to best suit the target environment; (2) custom algorithms and statistical techniques to process and time-align raw data originating from the sensor suite; (3) probabilistic and statistical models designed to interpret the data into the human state of interest (e.g., cognitive workload, attention, fatigue); (4) and machine-learning techniques to predict upcoming performance based on the current pattern of events, and (5) display of each piece of information depending on the needs of the target user who may or may not want to drill down into the functioning of the system to determine how conclusions about human state and performance are determined. I will then focus in on our experimental results from our custom functional near-infrared spectroscopy sensor

  17. [Reproducibility of subjective refraction measurement].

    Science.gov (United States)

    Grein, H-J; Schmidt, O; Ritsche, A

    2014-11-01

    Reproducibility of subjective refraction measurement is limited by various factors. The main factors affecting reproducibility include the characteristics of the measurement method and of the subject and the examiner. This article presents the results of a study on this topic, focusing on the reproducibility of subjective refraction measurement in healthy eyes. The results of previous studies are not all presented in the same way by the respective authors and cannot be fully standardized without consulting the original scientific data. To the extent that they are comparable, the results of our study largely correspond largely with those of previous investigations: During repeated subjective refraction measurement, 95% of the deviation from the mean value was approximately ±0.2 D to ±0.65 D for the spherical equivalent and cylindrical power. The reproducibility of subjective refraction measurement in healthy eyes is limited, even under ideal conditions. Correct assessment of refraction results is only feasible after identifying individual variability. Several measurements are required. Refraction cannot be measured without a tolerance range. The English full-text version of this article is available at SpringerLink (under supplemental).

  18. Measuring the significance of workload on performance of cytotechnologists in gynecologic cytology: a study using rapid prescreening.

    Science.gov (United States)

    Deschenes, Majorie; Renshaw, Andrew A; Auger, Manon

    2008-06-25

    Workload is extensively regulated and often used as a measure of quality in gynecologic cytology. Whether workload correlates with the sensitivity of screening in gynecologic cytology is not known. The sensitivity of gynecologic cytology screening was measured over an 8-month period using the result of full screening coupled with the results of rapid prescreening. Sensitivity results were then correlated with daily workload volumes and the experience level of individual cytotechnologists. Rapid prescreening had an average sensitivity of 41.9% for atypical squamous cells of undetermined significance (ASCUS) and above. Full screening had a corrected sensitivity of 82.2% for ASCUS and above. Rapid prescreening increased the sensitivity of the laboratory to 89.9%. The sensitivity of full screening was significantly different between cytotechnologists (79.2% vs 99%, P .05). When sensitivity and workload were examined on a monthly basis, there was no significant difference between sensitivity either as a group or individually at the highest and lowest workloads (P > .40 for all). Screeners sensitivity in gynecologic cytology appears to be unrelated to the experience level of individual cytotechnologists or to their workload at the levels examined. (c) 2008 American Cancer Society.

  19. Personality traits moderate the effect of workload sources on perceived workload in flying column police officers

    Directory of Open Access Journals (Sweden)

    Carlo eChiorri

    2015-11-01

    Full Text Available Previous research has suggested that personality traits of the Five Factor Model play a role in worker's response to workload. The aim of this study was to investigate the association of personality traits of first responders with their perceived workload in real-life tasks. A flying column of 269 police officers completed a measure of subjective workload (NASA-Task Load Index after intervention tasks in a major public event. Officers' scores on a measure of Five Factor Model personality traits were obtained from archival data. Linear Mixed Modeling was used to test the direct and interaction effects of personality traits on workload scores once controlling for background variables, task type and workload source (mental, temporal and physical demand of the task, perceived effort, dissatisfaction for the performance and frustration due to the task. All personality traits except extraversion significantly interacted at least with one workload source. Perceived workload in flying column police officers appears to be the result of their personality characteristics interacting with the workload source. The implications of these results for the development of support measures aimed at reducing the impact of workload in this category of workers are discussed.

  20. Brain-wave measures of workload in advanced cockpits: The transition of technology from laboratory to cockpit simulator, phase 2

    Science.gov (United States)

    Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.

    1989-01-01

    The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.

  1. Development and validation of a surgical workload measure: the surgery task load index (SURG-TLX).

    Science.gov (United States)

    Wilson, Mark R; Poolton, Jamie M; Malhotra, Neha; Ngo, Karen; Bright, Elizabeth; Masters, Rich S W

    2011-09-01

    The purpose of the present study was to develop and validate a multidimensional, surgery-specific workload measure (the SURG-TLX), and to determine its utility in providing diagnostic information about the impact of various sources of stress on the perceived demands of trained surgical operators. As a wide range of stressors have been identified for surgeons in the operating room, the current approach of considering stress as a unidimensional construct may not only limit the degree to which underlying mechanisms may be understood but also the degree to which training interventions may be successfully matched to particular sources of stress. The dimensions of the SURG-TLX were based on two current multidimensional workload measures and developed via focus group discussion. The six dimensions were defined as mental demands, physical demands, temporal demands, task complexity, situational stress, and distractions. Thirty novices were trained on the Fundamentals of Laparoscopic Surgery (FLS) peg transfer task and then completed the task under various conditions designed to manipulate the degree and source of stress experienced: task novelty, physical fatigue, time pressure, evaluation apprehension, multitasking, and distraction. The results were supportive of the discriminant sensitivity of the SURG-TLX to different sources of stress. The sub-factors loaded on the relevant stressors as hypothesized, although the evaluation pressure manipulation was not strong enough to cause a significant rise in situational stress. The present study provides support for the validity of the SURG-TLX instrument and also highlights the importance of considering how different stressors may load surgeons. Implications for categorizing the difficulty of certain procedures, the implementation of new technology in the operating room (man-machine interface issues), and the targeting of stress training strategies to the sources of demand are discussed. Modifications to the scale to enhance

  2. Comparison of real-time relative workload measurements in rail signallers

    NARCIS (Netherlands)

    van Broekhoven, Rob; Siegel, A.W.; Schraagen, Johannes Martinus Cornelis; Noordzij, Matthijs Leendert; Milius, Birgit; Naumann, Anja

    2016-01-01

    This exploratory field study investigated the weak resilience signals of workload in a rail traffic control room. The goals of this research are to see whether real-time system information of a rail control post can be used to predict workload of a rail signaller in real-time (Siegel & Schraagen,

  3. Using workload measurement tools in diverse care contexts: the experience of staff in mental health and learning disability inpatient settings.

    Science.gov (United States)

    Fanneran, T; Brimblecombe, N; Bradley, E; Gregory, S

    2015-12-01

    What is known on the subject? Difficulties with the recruitment and retention of qualified nursing staff have resulted in nursing shortages worldwide with a consequential impact on the quality of care. It is increasingly recommended that evidence-based staffing levels are central to the development of workforce plans. Due to a paucity of empirical research in mental health and learning disability services the staffing needs and requirements for these settings are undefined and the availability of tools to aid staffing decisions is limited. What this paper adds to existing knowledge? This paper provides a valuable insight into the practical uses of these tools as perceived by staff members with day-to-day experience of the requirements of mental health and learning disability wards. It reveals that while workload measurement tools are considered a valuable aid for the development of workforce plans, they are limited in their ability to capture all aspects of care provision in these settings. It further emphasizes the inapplicability of a one-shoe-fits-all approach for determining nurse staffing levels and the need for individual and customized workforce plans. What are the implications for practice? This study demonstrates that the development of tools for use in mental health and learning disability services is in its infancy, yet no tool that has been validated as such. It highlights the potential for workload measurement tools to aid staffing decisions; however, a more holistic approach that considers additional factors is needed to ensure robust workforce planning models are developed for these services. The critical challenge of determining the correct level and skill mix of nursing staff required to deliver safe and effective health care has become an international concern. It is recommended that evidence-based staffing decisions are central to the development of future workforce plans. Workforce planning in mental health and learning disability nursing is

  4. Effects of measurement strategy and statistical analysis on dose-response relations between physical workload and low back pain

    NARCIS (Netherlands)

    J.J.P. Jansen (Justin); A. Burdorf (Alex)

    2003-01-01

    textabstractBACKGROUND: In epidemiological studies on physical workloads and back complaints, among the important features in modelling dose-response relations are the measurement strategy of the exposure and the nature of the dose-response relation that is assumed. AIM: To

  5. [Subjective Workload, Job Satisfaction, and Work-Life-Balance of Physicians and Nurses in a Municipal Hospital in a Rural Area Compared to an Urban University Hospital].

    Science.gov (United States)

    Körber, Michael; Schmid, Klaus; Drexler, Hans; Kiesel, Johannes

    2017-02-15

    Medical and nursing shortages in rural areas represent a current serious public health problem. The healthcare of the rural population is at risk. This study compares perceived workload, job satisfaction and work-life balance of physicians and nurses at a clinic in a rural area with two clinics of a University hospital. Physicians and nurses were interviewed anonymously with a standardized questionnaire (paper and pencil), including questions on job satisfaction, subjective workload and work-life balance. The response rate was almost 50% in the University hospital as well as in the municipal hospital. 32 physicians and 54 nurses from the University hospital and 18 physicians and 137 nurses from the municipal hospital participated in the survey. Nurses at the University hospital assessed the organization of the daily routine with 94.1% as better than those at the municipal hospital (82.4%, p=0.03). Physicians at the University hospital were able to better implement acquired knowledge at a University clinic with 87.5% than their counterparts at the municipal hospital (55.5%, p=0.02). In contrast to their colleagues at the municipal hospital, only 50% of the physicians at the University hospital subjectively considered their workload as just right (83.3% municipal, p=0.02). 96.9% of the physicians at the University hospital were "daily" or "several times a week" under time pressure (municipal 50%, pwork and family life (62.9% University hospital, 72.8% Municipal hospital). In contrast, only 20% of the physicians at the University Hospital but 42.9% of the physicians of the municipal hospital had sufficient opportunities to balance workload and family (p=0.13). The return rate of almost 50% can be described as good. Due to the small number of physicians, especially from the municipal hospital, it can be assumed that some interesting differences could not be detected. There were only slight differences between the nurses from the two hospitals. In contrast, subjective

  6. Measuring workload using a combination of electroencephalography and near infrared spectroscopy

    NARCIS (Netherlands)

    Coffey, E.B.J.; Brouwer, A.M.; Erp, J.B.F. van

    2012-01-01

    The ability to continuously monitor workload in a real-world environment would have important implications for the offline design of human machine interfaces as well as the real-time online improvement of interaction between humans and machines. The present study explored the usefulness of combining

  7. Determining a set of measurable and relevant factors affecting nursing workload in the acute care hospital setting: a cross-sectional study.

    Science.gov (United States)

    Myny, Dries; Van Hecke, Ann; De Bacquer, Dirk; Verhaeghe, Sofie; Gobert, Micheline; Defloor, Tom; Van Goubergen, Dirk

    2012-04-01

    While there has been great interest in the effect of nurse staffing levels have on the quality of care in hospitals, less attention has been given to determining the factors that affect the nursing workload. There are no existing studies that help define measurable factors that have a clear relation to nursing workload. The aim of this study was to determine the most important and measurable factors, other than patient acuity, that influence nursing workload. A cross-sectional design. Hospitals within the acute hospital care setting. Persons with a nursing educational background, working in Belgian acute care hospitals. A self-administered questionnaire was developed based on the results of an integrative review, the use of focus groups and a survey on measurability and relevance of the included factors. The questionnaire listed relevant and measurable factors related to nursing workload. Weight and frequency of each factor was assessed. The initial list consisted of 94 factors. These factors were regrouped and organised into a questionnaire of 28 measurable and sufficiently relevant factors affecting the nursing workload. More than half of the initial factors seemed to be relevant, but hard to measure on a daily basis. Based on the impact of each factor, the number of work interruptions was the most important factor related to nursing workload. It is unlikely that a workload instrument will ever be able to take into account all possible factors affecting the nursing workload. Nevertheless, the number of work interruptions, the patient turnover rate and the number of mandatory registrations should be included in the development or revision of a workload measurement tool. © 2011 Elsevier Ltd. All rights reserved.

  8. Development of NPP control room operators`s mental workload measurement system using bioelectric signals

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Bong Sik; Oh, In Seok; Lee, Hyun Cheol; Cha, Kyung Ho [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Lee, Dong Ha [Suwon Univ., Suwon (Korea, Republic of)

    1996-09-01

    This study developed mentalload measurement system based on the relations between mentalload and physiological responses of the human operators. The measurement system was composed of the telemetry system for EEG, EOG, ECG and respiration pattern of the subjects, A/D converter, the physiological signal processing programs (compiled by the Labview). The signal processing programs transformed the physiological signal into the scores indicating mentalload status of the subjects and recorded the mentalload scores in the form of the table of a database. The acqknowledge and the labview programs additionally transformed the mentalload score database and the operator behavior database so that both database were consolidated into one. 94 figs., 57 refs. (Author).

  9. Measuring professional satisfaction and nursing workload among nursing staff at a Greek Coronary Care Unit

    Directory of Open Access Journals (Sweden)

    Maria Gouzou

    2015-12-01

    Full Text Available ABSTRACT Objective To explore potential associations between nursing workload and professional satisfaction among nursing personnel (NP in Greek Coronary Care Units (CCUs. Method A cross-sectional study was performed involving 66 members of the NP employed in 6 randomly selected Greek CCUs. Job satisfaction was assessed by the IWS and nursing workload by NAS, CNIS and TISS-28. Results The response rate was 77.6%. The reliability of the IWS was α=0.78 and the mean score 10.7 (±2.1, scale range: 0.5-39.7. The most highly valued component of satisfaction was “Pay”, followed by “Task requirements”, “Interaction”, “Professional status”, “Organizational policies” and “Autonomy”. NAS, CNIS and TISS-28 were negatively correlated (p≤0.04 with the following work components: “Autonomy”, “Professional status”, “Interaction” and “Task requirements”. Night shift work independently predicted the score of IWS. Conclusion The findings show low levels of job satisfaction, which are related with nursing workload and influenced by rotating shifts.

  10. Faculty Perceptions of Workload: A Human Factor's Approach to Instrument Development.

    Science.gov (United States)

    Neill, Denise

    2017-04-01

    Research revealed nursing faculty members' perceived workload measures do not adequately capture the complexity of their workload. Using a human factors approach to address the multiple complex dimensions from the subjective perception of the worker, the Nurse Faculty Workload Assessment (NFWA) was developed. Survey data from 565 faculty members were used to establish the instrument's psychometric properties. NWFA Sections 1, 2, and 3 demonstrated reliability and internal consistency. Findings supported interrelationships between activity complexity, performance circumstances, and individual characteristics described in human factors workload literature. The NFWA provides a tool for administrators to evaluate faculty perception of workload expectations. Further study is needed to refine the NFWA and to compare the perception of faculty regarding workload using various workload formula calculations in various nursing programs.

  11. Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study

    Science.gov (United States)

    Yu, K.; Prasad, I.; Mir, H.; Thakor, N.; Al-Nashash, H.

    2015-08-01

    Objective. Our experiments explored the effect of visual stimuli degradation on cognitive workload. Approach. We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload. Main results. These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels. Significance. Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.

  12. Individual differences in cardiorespiratory measures of mental workload: An investigation of negative affectivity and cognitive avoidant coping in pilot candidates.

    Science.gov (United States)

    Grassmann, Mariel; Vlemincx, Elke; von Leupoldt, Andreas; Van den Bergh, Omer

    2017-03-01

    Cardiorespiratory measures provide useful information in addition to well-established self-report measures when monitoring operator capacity. The purpose of our study was to refine the assessment of operator load by considering individual differences in personality and their associations with cardiorespiratory activation. Physiological and self-report measures were analyzed in 115 pilot candidates at rest and while performing a multiple task covering perceptual speed, spatial orientation, and working memory. In the total sample and particularly in individuals with a general tendency to worry a lot, a cognitive avoidant coping style was associated with a smaller task-related increase in heart rate. Negative affectivity was found to moderate the association between cardiac and self-reported arousal. Given that physiological and self-report measures of mental workload are usually combined when evaluating operator load (e.g., in pilot selection and training), our findings suggest that integrating individual differences may reduce unexplained variance and increase the validity of workload assessments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Modeling complexity in pathologist workload measurement: the Automatable Activity-Based Approach to Complexity Unit Scoring (AABACUS).

    Science.gov (United States)

    Cheung, Carol C; Torlakovic, Emina E; Chow, Hung; Snover, Dale C; Asa, Sylvia L

    2015-03-01

    Pathologists provide diagnoses relevant to the disease state of the patient and identify specific tissue characteristics relevant to response to therapy and prognosis. As personalized medicine evolves, there is a trend for increased demand of tissue-derived parameters. Pathologists perform increasingly complex analyses on the same 'cases'. Traditional methods of workload assessment and reimbursement, based on number of cases sometimes with a modifier (eg, the relative value unit (RVU) system used in the United States), often grossly underestimate the amount of work needed for complex cases and may overvalue simple, small biopsy cases. We describe a new approach to pathologist workload measurement that aligns with this new practice paradigm. Our multisite institution with geographically diverse partner institutions has developed the Automatable Activity-Based Approach to Complexity Unit Scoring (AABACUS) model that captures pathologists' clinical activities from parameters documented in departmental laboratory information systems (LISs). The model's algorithm includes: 'capture', 'export', 'identify', 'count', 'score', 'attribute', 'filter', and 'assess filtered results'. Captured data include specimen acquisition, handling, analysis, and reporting activities. Activities were counted and complexity units (CUs) generated using a complexity factor for each activity. CUs were compared between institutions, practice groups, and practice types and evaluated over a 5-year period (2008-2012). The annual load of a clinical service pathologist, irrespective of subspecialty, was ∼40,000 CUs using relative benchmarking. The model detected changing practice patterns and was appropriate for monitoring clinical workload for anatomical pathology, neuropathology, and hematopathology in academic and community settings, and encompassing subspecialty and generalist practices. AABACUS is objective, can be integrated with an LIS and automated, is reproducible, backwards compatible

  14. The Ontario nursing workload demonstration projects: rethinking how we measure, cost and plan the work of nurses.

    Science.gov (United States)

    Ferguson-Paré, Mary; Bandurchin, Annabelle

    2010-05-01

    In 2008 the Nursing Secretariat of Ontario's Ministry of Health and Long-Term Care formed a Nursing Workload Steering Committee to oversee the implementation of three demonstration projects with the objectives: to assess the feasibility of Health Outcomes for Better Information and Care (HOBIC) data as a measure of nursing workload, determine the indicators that best support nurse leaders to measure nursing work and make informed staffing decisions, and develop a model that predicts acute care nursing costs. Three HOBIC scales--activities of daily living (ADLs), continence and fatigue--explained a small amount of the variance in nurse judgment of the amount of nursing time patients require in the first 24 hours of care. Nurses in the study appreciated providing their professional judgment to help estimate the nursing work requirements of patients. The priority and secondary indicators most important for decision-making included medical severity of patients, environmental complexity, nurse experience, patient turnover, nurse-to-patient ratio, cognitive status, infection control, nurse vacancy, predictability of patient types, nursing interventions, patient volumes, co-morbidities, patient self-care abilities, physical and psychosocial functioning, unit type and medical diagnosis. A fairly robust model was developed using existing data sources to estimate nursing input into a patient's costs. The model explained between 69% and 80% of the variation in nursing costs for each patient. In order to effectively measure, plan and cost nursing, we need to determine what nursing is. In the future, recognition of nurses as knowledge workers will require us to consider the many patient and environmental factors that affect the ability of nurses to apply their professional judgment to care for patients.

  15. Subjective measures of well--being

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    2007-01-01

    textabstractThis chapter deals with three question: 1) What are ‘subjective’ measure? 2) What is ‘wellbeing’? and 3) Are subjective measures of wellbeing of use for policymaking, in particular in developing nations? The first question is answered by making a distinction between two kinds of

  16. Impact of Conflict Avoidance Responsibility Allocation on Pilot Workload in a Distributed Air Traffic Management System

    Science.gov (United States)

    Ligda, Sarah V.; Dao, Arik-Quang V.; Vu, Kim-Phuong; Strybel, Thomas Z.; Battiste, Vernol; Johnson, Walter W.

    2010-01-01

    Pilot workload was examined during simulated flights requiring flight deck-based merging and spacing while avoiding weather. Pilots used flight deck tools to avoid convective weather and space behind a lead aircraft during an arrival into Louisville International airport. Three conflict avoidance management concepts were studied: pilot, controller or automation primarily responsible. A modified Air Traffic Workload Input Technique (ATWIT) metric showed highest workload during the approach phase of flight and lowest during the en-route phase of flight (before deviating for weather). In general, the modified ATWIT was shown to be a valid and reliable workload measure, providing more detailed information than post-run subjective workload metrics. The trend across multiple workload metrics revealed lowest workload when pilots had both conflict alerting and responsibility of the three concepts, while all objective and subjective measures showed highest workload when pilots had no conflict alerting or responsibility. This suggests that pilot workload was not tied primarily to responsibility for resolving conflicts, but to gaining and/or maintaining situation awareness when conflict alerting is unavailable.

  17. Higher mental workload is associated with poorer laparoscopic performance as measured by the NASA-TLX tool.

    Science.gov (United States)

    Yurko, Yuliya Y; Scerbo, Mark W; Prabhu, Ajita S; Acker, Christina E; Stefanidis, Dimitrios

    2010-10-01

    Increased workload during task performance may increase fatigue and facilitate errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a previously validated tool for workload self-assessment. We assessed the relationship of workload and performance during simulator training on a complex laparoscopic task. NASA-TLX workload data from three separate trials were analyzed. All participants were novices (n = 28), followed the same curriculum on the fundamentals of laparoscopic surgery suturing model, and were tested in the animal operating room (OR) on a Nissen fundoplication model after training. Performance and workload scores were recorded at baseline, after proficiency achievement, and during the test. Performance, NASA-TLX scores, and inadvertent injuries during the test were analyzed and compared. Workload scores declined during training and mirrored performance changes. NASA-TLX scores correlated significantly with performance scores (r = -0.5, P NASA-TLX questionnaire accurately reflects workload changes during simulator training and may identify individuals more likely to experience high workload and more prone to errors during skill transfer to the clinical environment.

  18. ON THE USEFULNESS OF FINGER BLOOD-PRESSURE MEASUREMENTS FOR STUDIES ON MENTAL WORKLOAD

    NARCIS (Netherlands)

    VELDMAN, JBP; RUDDEL, H; ROBBE, HWJ; Mulder, Lambertus; Mulder, Gysbertus

    Two experiments were conducted to explore the usefulness of the Penaz method for non-invasive, continuous finger blood pressure measurements during mental stress testing. In the first study, blood pressure was measured with the Penaz method, in the second it was measured intra-arterially. Two

  19. Towards Diagram Understanding: A Pilot Study Measuring Cognitive Workload Through Eye-Tracking

    DEFF Research Database (Denmark)

    Maier, Anja; Baltsen, Nick; Christoffersen, Henrik

    2014-01-01

    We investigate model understanding, in particular , how the quality of the UML diagram layout impacts cognitive load. We hypothesize that this w ill have a significant impact on the structure and effectiveness of engineers’ communication. In previous work, we have studied task performance measure...... understanding. Our results also give rise to a number of new hypotheses about diagram understanding strategies that we are investigating in an ongoing data acquisition campaign....

  20. Experimental validation of navigation workload metrics

    Energy Technology Data Exchange (ETDEWEB)

    Schryver, J.C. [Oak Ridge National Lab., TN (United States); Wachtel, J.A. [Nuclear Regulatory Commission, Rockville, MD (United States). Office of Nuclear Regulatory Research

    1994-04-01

    Advanced digital computer display interfaces in the control room may increase operator workload. Workstation monitors provide limited display area, and information is represented in large-scale display networks. Display navigation may generate disorienting effects, require additional resources for window management, and increase memory and data integration requirements. Six ORNL employees participated in an experiment to validate proposed metrics of navigation workload in the advanced control room. The task environment was a display network consisting of 25 windows resembling a simplified Safety Parameter Display System for Pressurized Water Reactors. A repeated measures design with 3 within subjects factors was employed. The factors were task difficulty, navigation distance level, and a blocking factor. Participants were asked to monitor a single parameter or two parameters. Fourteen candidate metrics were tested. Analysis of variance of the modified task load index (MTLX) and rating subscales demonstrated substantial support for the claim that navigation of large-scale display networks can impose additional mental load. Primary and secondary task performance measures exhibited ceiling effects. Memory probes for these tasks were inadequate because they were recognition-based and coarse. Eye gaze measures were not validated, indicating a need for more refined data reduction algorithms. Strong positive correlations were found between MTLX and both navigation duration and standard deviation of pupil diameter. Further study and increased statistical power are required to validate objective navigation workload metrics.

  1. Online EEG-Based Workload Adaptation of an Arithmetic Learning Environment.

    Science.gov (United States)

    Walter, Carina; Rosenstiel, Wolfgang; Bogdan, Martin; Gerjets, Peter; Spüler, Martin

    2017-01-01

    In this paper, we demonstrate a closed-loop EEG-based learning environment, that adapts instructional learning material online, to improve learning success in students during arithmetic learning. The amount of cognitive workload during learning is crucial for successful learning and should be held in the optimal range for each learner. Based on EEG data from 10 subjects, we created a prediction model that estimates the learner's workload to obtain an unobtrusive workload measure. Furthermore, we developed an interactive learning environment that uses the prediction model to estimate the learner's workload online based on the EEG data and adapt the difficulty of the learning material to keep the learner's workload in an optimal range. The EEG-based learning environment was used by 13 subjects to learn arithmetic addition in the octal number system, leading to a significant learning effect. The results suggest that it is feasible to use EEG as an unobtrusive measure of cognitive workload to adapt the learning content. Further it demonstrates that a promptly workload prediction is possible using a generalized prediction model without the need for a user-specific calibration.

  2. Online EEG-Based Workload Adaptation of an Arithmetic Learning Environment

    Science.gov (United States)

    Walter, Carina; Rosenstiel, Wolfgang; Bogdan, Martin; Gerjets, Peter; Spüler, Martin

    2017-01-01

    In this paper, we demonstrate a closed-loop EEG-based learning environment, that adapts instructional learning material online, to improve learning success in students during arithmetic learning. The amount of cognitive workload during learning is crucial for successful learning and should be held in the optimal range for each learner. Based on EEG data from 10 subjects, we created a prediction model that estimates the learner's workload to obtain an unobtrusive workload measure. Furthermore, we developed an interactive learning environment that uses the prediction model to estimate the learner's workload online based on the EEG data and adapt the difficulty of the learning material to keep the learner's workload in an optimal range. The EEG-based learning environment was used by 13 subjects to learn arithmetic addition in the octal number system, leading to a significant learning effect. The results suggest that it is feasible to use EEG as an unobtrusive measure of cognitive workload to adapt the learning content. Further it demonstrates that a promptly workload prediction is possible using a generalized prediction model without the need for a user-specific calibration. PMID:28611615

  3. Cognitive workload and sleep restriction interact to influence sleep homeostatic responses.

    Science.gov (United States)

    Goel, Namni; Abe, Takashi; Braun, Marcia E; Dinges, David F

    2014-11-01

    Determine the effects of high versus moderate workload on sleep physiology and neurobehavioral measures, during sleep restriction (SR) and no sleep restriction (NSR) conditions. Ten-night experiment involving cognitive workload and SR manipulations. Controlled laboratory environment. Sixty-three healthy adults (mean ± standard deviation: 33.2 ± 8.7 y; 29 females), age 22-50 y. Following three baseline 8 h time in bed (TIB) nights, subjects were randomized to one of four conditions: high cognitive workload (HW) + SR; moderate cognitive workload (MW) + SR; HW + NSR; or MW + NSR. SR entailed 5 consecutive nights at 4 h TIB; NSR entailed 5 consecutive nights at 8 h TIB. Subjects received three workload test sessions/day consisting of 15-min preworkload assessments, followed by a 60-min (MW) or 120-min (HW) workload manipulation comprised of visually based cognitive tasks, and concluding with 15-min of postworkload assessments. Experimental nights were followed by two 8-h TIB recovery sleep nights. Polysomnography was collected on baseline night 3, experimental nights 1, 4, and 5, and recovery night 1 using three channels (central, frontal, occipital [C3, Fz, O2]). High workload, regardless of sleep duration, increased subjective fatigue and sleepiness (all P sleep restriction produced cumulative increases in Psychomotor Vigilance Test (PVT) lapses, fatigue, and sleepiness and decreases in PVT response speed and Maintenance of Wakefulness Test (MWT) sleep onset latencies (all P sleep onset latencies (P sleep onset (P sleep homeostasis-was higher at O2 than C3 only in the HW + SR condition (P sleep onset, but it also promoted sleep homeostatic responses by increasing subjective fatigue and sleepiness, and producing a global sleep homeostatic response by reducing wake after sleep onset. When combined with sleep restriction, high workload increased local (occipital) sleep homeostasis, suggesting a use-dependent sleep response to visual work. We conclude that sleep

  4. How we can measure the non-driving-task engagement in automated driving: Comparing flow experience and workload.

    Science.gov (United States)

    Ko, Sang Min; Ji, Yong Gu

    2018-02-01

    In automated driving, a driver can completely concentrate on non-driving-related tasks (NDRTs). This study investigated the flow experience of a driver who concentrated on NDRTs and tasks that induce mental workload under conditional automation. Participants performed NDRTs under different demand levels: a balanced demand-skill level (fit condition) to induce flow, low-demand level to induce boredom, and high-demand level to induce anxiety. In addition, they performed the additional N-Back task, which artificially induces mental workload. The results showed participants had the longest reaction time when they indicated the highest flow score, and had the longest gaze-on time, road-fixation time, hands-on time, and take-over time under the fit condition. Significant differences were not observed in the driver reaction times in the fit condition and the additional N-Back task, indicating that performing NDRTs that induce a high flow experience could influence driver reaction time similar to performing tasks with a high mental workload. Copyright © 2017. Published by Elsevier Ltd.

  5. The Validity of Subjective Performance Measures

    DEFF Research Database (Denmark)

    Meier, Kenneth J.; Winter, Søren C.; O'Toole, Laurence J.

    2015-01-01

    Public management studies are increasingly using survey data on managers’ perceptions of performance to measure organizational performance. The perceptual measures are tempting to apply because archival performance data or surveys of target group outcomes and satisfaction are often lacking, costly...... to provide, and are highly policy specific rendering generalization difficult. But are perceptual performance measures valid, and do they generate unbiased findings? We examine these questions in a comparative study of middle managers in schools in Texas and Denmark. The findings are remarkably similar...... the resources it has. Even worse, the use of perceptual performance measures seems to provide biased estimates when examining how management affects performance....

  6. Measured by the oxygen uptake in the field, the work of refuse collectors is particularly hard work: Are the limit values for physical endurance workload too low?

    Science.gov (United States)

    Preisser, Alexandra M; Zhou, Linfei; Velasco Garrido, Marcial; Harth, Volker

    2016-02-01

    Collecting waste is regarded as a benchmark for "particularly heavy" work. This study aims to determine and compare the workload of refuse workers in the field. We examined heart rate (HR) and oxygen uptake as parameters of workload during their daily work. Sixty-five refuse collectors from three task-specific groups (residual and organic waste collection, and street sweeping) of the municipal sanitation department in Hamburg, Germany, were included. Performance was determined by cardiopulmonary exercise testing (CPX) under laboratory conditions. Additionally, the oxygen uptake (VO2) and HR under field conditions (1-h morning shift) were recorded with a portable spiroergometry system and a pulse belt. There was a substantial correlation of both absolute HR and VO2 during CPX [HR/VO2 R 0.89 (SD 0.07)] as well as during field measurement [R 0.78 (0.19)]. Compared to reference limits for heavy work, 44% of the total sample had shift values above 30% heart rate reserve (HRR); 34% of the individuals had mean HR during work (HRsh) values that were above the HR corresponding to 30% of individual maximum oxygen uptake (VO2,max). All individuals had a mean oxygen uptake (VO2,1h) above 30% of VO2,max. HR as well as the measurement of VO2 can be valuable tools for investigating physiological workload, not only under laboratory conditions but also under normal working conditions in the field. Both in terms of absolute and relative HR and oxygen consumption, employment as a refuse collector should be classified in the upper range of defined heavy work. The limit of heavy work at about 33% of the individual maximum load at continuous work should be reviewed.

  7. Associations of objectively and subjectively measured physical ...

    African Journals Online (AJOL)

    PBSSs) calculated from physical activity (PA) questionnaires and accelerometry measures of PA with trabecular and cortical bone properties in prepubertal children. Methods. We compared PBSSs calculated from the bone-specific component of PA ...

  8. Effects of mental workload and fatigue on the P300, alpha and theta band power during operation of an ERP (P300) brain-computer interface.

    Science.gov (United States)

    Käthner, Ivo; Wriessnegger, Selina C; Müller-Putz, Gernot R; Kübler, Andrea; Halder, Sebastian

    2014-10-01

    The study aimed at revealing electrophysiological indicators of mental workload and fatigue during prolonged usage of a P300 brain-computer interface (BCI). Mental workload was experimentally manipulated with dichotic listening tasks. Medium and high workload conditions alternated. Behavioral measures confirmed that the manipulation of mental workload was successful. Reduced P300 amplitude was found for the high workload condition. Along with lower performance and an increase in the subjective level of fatigue, an increase of power in the alpha band was found for the last as compared to the first run of both conditions. The study confirms that a combination of signals derived from the time and frequency domain of the electroencephalogram is promising for the online detection of workload and fatigue. It also demonstrates that satisfactory accuracies can be achieved by healthy participants with the P300 speller, despite constant distraction and when pursuing the task for a long time. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Subjective Optic Disc Assessment and Single Measurement ...

    African Journals Online (AJOL)

    Verbal consent was obtained from the Treasury Department of the Rivers State Ministry of Finance and also from all individuals who participated in the study. Demographic data including age and sex were recorded in the WHO/PBL eye examination form. Ocular examination consisted of uncorrected VA measured with ...

  10. Debriefing decreases mental workload in surgical crisis: A randomized controlled trial.

    Science.gov (United States)

    Boet, Sylvain; Sharma, Bharat; Pigford, Ashlee-Ann; Hladkowicz, Emily; Rittenhouse, Neil; Grantcharov, Teodor

    2017-05-01

    Mental workload is the amount of mental effort involved in performing a particular task. Crisis situations may increase mental workload, which can subsequently negatively impact operative performance and patient safety. This study aims to measure the impact of learning through debriefing and a systematic approach to crisis on trainees' mental workload in a simulated surgical crisis. Twenty junior surgical residents participated in a high-fidelity, simulated, postoperative crisis in a surgical ward environment (pretest). Participants were randomized to either an instructor-led debriefing, including performance feedback (intervention; n = 10) or no debriefing (control; n = 10). Subjects then immediately managed a second simulated crisis (post-test). Mental workload was assessed in real time during the scenarios using a previously validated, wireless, vibrotactile device. Mental workload was represented by subject response times to the vibrations, which were recorded and analyzed using the Mann-Whitney U test. Participants in the debriefing arm had a significantly reduced median response time in milliseconds (post-test minus pretest -695, quartile range -2,136 to -297) compared to participants in the control arm (42, -1,191 to 763), (between-arm difference P = .049). Debriefing after simulated surgical crisis situations may improve performance by decreasing trainee's mental workload during a subsequent simulated surgical crisis. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Reproducibility of single-subject functional connectivity measurements

    National Research Council Canada - National Science Library

    Anderson, J S; Ferguson, M A; Lopez-Larson, M; Yurgelun-Todd, D

    2011-01-01

    .... We collected data to characterize how much imaging time is necessary to obtain reproducible quantitative functional connectivity measurements needed for a reliable single-subject diagnostic test...

  12. Working memory’s workload capacity

    National Research Council Canada - National Science Library

    Heathcote, Andrew; Coleman, James R; Eidels, Ami; Watson, Jason M; Houpt, Joseph; Strayer, David L

    2015-01-01

    ... (Journal of Mathematical Psychology 39: 321–359, 1995) workload capacity measure, which revealed that the decrement in dual two-back performance was mediated by the sharing of a limited amount of processing capacity...

  13. Hopper Workload Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Austin, Brian; Butler, Tina; Gerber, Richard; Whitney, Cary; Wright, Nicholas; Yang, Woo-Sun; Zhao, Zhengji

    2014-05-02

    The National Energy Research Scientific Computing (NERSC) Center is the primary computing facility for the United States Department of Energy, Office of Science. With over 5,000 users and over 600 different applications utilizing NERSC systems, it is critically important to examine the workload running on NERSCs large supercomputers in order to procure systems that perform well for a broad workload. In this paper we show the breakdown of the NERSC workload by science area, algorithm, memory, thread usage and more. We also describe the methods used to collect data from NERSCs Hopper (Cray XE6) system.

  14. Cognitive Workload and Sleep Restriction Interact to Influence Sleep Homeostatic Responses

    Science.gov (United States)

    Goel, Namni; Abe, Takashi; Braun, Marcia E.; Dinges, David F.

    2014-01-01

    Study Objectives: Determine the effects of high versus moderate workload on sleep physiology and neurobehavioral measures, during sleep restriction (SR) and no sleep restriction (NSR) conditions. Design: Ten-night experiment involving cognitive workload and SR manipulations. Setting: Controlled laboratory environment. Participants: Sixty-three healthy adults (mean ± standard deviation: 33.2 ± 8.7 y; 29 females), age 22–50 y. Interventions: Following three baseline 8 h time in bed (TIB) nights, subjects were randomized to one of four conditions: high cognitive workload (HW) + SR; moderate cognitive workload (MW) + SR; HW + NSR; or MW + NSR. SR entailed 5 consecutive nights at 4 h TIB; NSR entailed 5 consecutive nights at 8 h TIB. Subjects received three workload test sessions/day consisting of 15-min preworkload assessments, followed by a 60-min (MW) or 120-min (HW) workload manipulation comprised of visually based cognitive tasks, and concluding with 15-min of postworkload assessments. Experimental nights were followed by two 8-h TIB recovery sleep nights. Polysomnography was collected on baseline night 3, experimental nights 1, 4, and 5, and recovery night 1 using three channels (central, frontal, occipital [C3, Fz, O2]). Measurements and Results: High workload, regardless of sleep duration, increased subjective fatigue and sleepiness (all P sleep restriction produced cumulative increases in Psychomotor Vigilance Test (PVT) lapses, fatigue, and sleepiness and decreases in PVT response speed and Maintenance of Wakefulness Test (MWT) sleep onset latencies (all P sleep onset latencies (P sleep onset (P sleep homeostasis—was higher at O2 than C3 only in the HW + SR condition (P sleep onset, but it also promoted sleep homeostatic responses by increasing subjective fatigue and sleepiness, and producing a global sleep homeostatic response by reducing wake after sleep onset. When combined with sleep restriction, high workload increased local (occipital) sleep

  15. Comparing subjective and objective measures of headgear compliance.

    Science.gov (United States)

    Bos, Annemieke; Kleverlaan, Cornelis J; Hoogstraten, Johan; Prahl-Andersen, Birte; Kuitert, Rein

    2007-12-01

    Many studies have used subjective measures to examine patient compliance during orthodontic treatment. Objective measurement of compliance has been confined to only a few studies that used electronic timing devices built into removable appliances. Our aim in this study was to compare subjective and objective methods of measuring compliance with headgear wear. It was hypothesized that orthodontists, patients, and patients' parents overestimate compliance and report more wearing hours than the headgear timers indicate. Also, relationships between sex, age, treatment time, and headgear compliance were explored. A headgear timer device and 3 questionnaires were developed to assess compliance. The subjects were unaware that their headgear use was being measured. Significant differences between the estimates of orthodontists, patients, parents, and headgear timer scores were found. Also, there were differences regarding age and treatment time. Subjective measures might result in overestimation of compliance. This suggests that the use of an objective instrument to measure headgear compliance should be continued in future studies.

  16. Assessment of operators’ mental workload using physiological and subjective measures in cement, city traffic and power plant controlcenters

    Directory of Open Access Journals (Sweden)

    Majid Fallahi

    2016-06-01

    Conclusion: The results suggested that when operators’ mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers.Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions.

  17. Polish adaptation of three self-report measures of job stressors: the Interpersonal Conflict at Work Scale, the Quantitative Workload Inventory and the Organizational Constraints Scale.

    Science.gov (United States)

    Baka, Łukasz; Bazińska, Róża

    2016-01-01

    The objective of the present study was to test the psychometric properties, reliability and validity of three job stressor measures, namely, the Interpersonal Conflict at Work Scale, the Organizational Constraints Scale and the Quantitative Workload Inventory. The study was conducted on two samples (N = 382 and 3368) representing a wide range of occupations. The estimation of internal consistency with Cronbach's α and the test-retest method as well as both exploratory and confirmatory factor analyses were the main statistical methods. The internal consistency of the scales proved satisfactory, ranging from 0.80 to 0.90 for Cronbach's α test and from 0.72 to 0.86 for the test-retest method. The one-dimensional structure of the three measurements was confirmed. The three scales have acceptable fit to the data. The one-factor structures and other psychometric properties of the Polish version of the scales seem to be similar to those found in the US version of the scales. It was also proved that the three job stressors are positively related to all the job strain measures. The Polish versions of the three analysed scales can be used to measure the job stressors in Polish conditions.

  18. State of science: mental workload in ergonomics.

    Science.gov (United States)

    Young, Mark S; Brookhuis, Karel A; Wickens, Christopher D; Hancock, Peter A

    2015-01-01

    Mental workload (MWL) is one of the most widely used concepts in ergonomics and human factors and represents a topic of increasing importance. Since modern technology in many working environments imposes ever more cognitive demands upon operators while physical demands diminish, understanding how MWL impinges on performance is increasingly critical. Yet, MWL is also one of the most nebulous concepts, with numerous definitions and dimensions associated with it. Moreover, MWL research has had a tendency to focus on complex, often safety-critical systems (e.g. transport, process control). Here we provide a general overview of the current state of affairs regarding the understanding, measurement and application of MWL in the design of complex systems over the last three decades. We conclude by discussing contemporary challenges for applied research, such as the interaction between cognitive workload and physical workload, and the quantification of workload 'redlines' which specify when operators are approaching or exceeding their performance tolerances.

  19. The smartphone and the driver's cognitive workload: A comparison of Apple, Google, and Microsoft's intelligent personal assistants.

    Science.gov (United States)

    Strayer, David L; Cooper, Joel M; Turrill, Jonna; Coleman, James R; Hopman, Rachel J

    2017-06-01

    The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple's Siri , Google's Google Now for Android phones, and Microsoft's Cortana ) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: "on-task" workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. A psychophysiological assessment of operator workload during simulated flight missions

    Science.gov (United States)

    Kramer, Arthur F.; Sirevaag, Erik J.; Braune, Rolf

    1987-01-01

    The applicability of the dual-task event-related (brain) potential (ERP) paradigm to the assessment of an operator's mental workload and residual capacity in a complex situation of a flight mission was demonstrated using ERP measurements and subjective workload ratings of student pilots flying a fixed-based single-engine simulator. Data were collected during two separate 45-min flights differing in difficulty; flight demands were examined by dividing each flight into four segments: takeoff, straight and level flight, holding patterns, and landings. The P300 ERP component in particular was found to discriminate among the levels of task difficulty in a systematic manner, decreasing in amplitude with an increase in task demands. The P300 amplitude is shown to be negatively correlated with deviations from command headings across the four flight segments.

  1. Measuring human wellbeing in Pakistan: objective versus subjective indicators

    OpenAIRE

    Haq, Rashida

    2009-01-01

    The concern for measuring wellbeing objectively and subjectively is found in modern political philosophy. This study explores objective indicators versus subjective perceptions of human wellbeing in ranking of survey data for districts of Pakistan. Data used for the analysis is ‘The Pakistan Social and Living Standards Measurement Survey’ for the year 2006-07. The human wellbeing is examined in four domains: education, health, living conditions and economic situation. Principal component anal...

  2. The workload of fishermen

    DEFF Research Database (Denmark)

    Østergaard, Helle; Jepsen, Jørgen Riis; Berg-Beckhoff, Gabriele

    2016-01-01

    the work environment of Danish fishermen with regard to their physical workload and ergonomic factors. Materials and methods: A cross sectional study was performed on a random sample of active Danish commercial fishermen (response rate: 28%) by means of a questionnaire on demographic and self...... on Danish seiners had higher workload scores than fishermen in other vessel types. Conclusions: Despite improved work environment in the Danish fishing industry, fishermen still experience high levels of workload and suboptimal ergonomic conditions, which are known to cause pain and impair musculoskeletal......Background: Fishery has always been perceived as a physically demanding industry of a manual character. In recent years the physical work environment has developed positively and consequently the current situation in not fully described in the existing literature. This study aims to describe...

  3. Subjective Narcosis Assessment Scale: measuring the subjective experience of nitrogen narcosis.

    Science.gov (United States)

    van Wijk, Charles H; Meintjes, W A J

    2014-01-01

    The interaction of subjective experiences and objective measures of neuropsychological performance during hyperbaric exposure has received less attention in the literature, in part due to the shortage of available and appropriately standardized measures. This study aimed to describe the psychometric properties of a modified version of the Subjective High Assessment Scale when used in the hyperbaric context, by exploring internal reliability, factor structure, associations with psychological variables and simple cognitive delayed recall, and the effect of task focus on the recall of subjective experience. Seventy qualified divers completed dry hyperbaric chamber dives to 607.95 kPa, and completed ratings of their subjective experiences. Some also completed a delayed recall task and psychological measures prior to their dives. The scale displayed good internal consistency, with four meaningful factors emerging. It showed some significant but small associations with trait anxiety and transient mood states, and a small to moderate correlation with recall performance. There was no significant effect of task focus on self-report of subjective experiences. The modified scale, renamed the Subjective Narcosis Assessment Scale here, has useful psychometric properties, and promising potential for future use.

  4. Comparing capacity coefficient and dual task assessment of visual multitasking workload

    Energy Technology Data Exchange (ETDEWEB)

    Blaha, Leslie M.

    2017-07-14

    Capacity coefficient analysis could offer a theoretically grounded alternative approach to subjective measures and dual task assessment of cognitive workload. Workload capacity or workload efficiency is a human information processing modeling construct defined as the amount of information that can be processed by the visual cognitive system given a specified of amount of time. In this paper, I explore the relationship between capacity coefficient analysis of workload efficiency and dual task response time measures. To capture multitasking performance, I examine how the relatively simple assumptions underlying the capacity construct generalize beyond the single visual decision making tasks. The fundamental tools for measuring workload efficiency are the integrated hazard and reverse hazard functions of response times, which are defined by log transforms of the response time distribution. These functions are used in the capacity coefficient analysis to provide a functional assessment of the amount of work completed by the cognitive system over the entire range of response times. For the study of visual multitasking, capacity coefficient analysis enables a comparison of visual information throughput as the number of tasks increases from one to two to any number of simultaneous tasks. I illustrate the use of capacity coefficients for visual multitasking on sample data from dynamic multitasking in the modified Multi-attribute Task Battery.

  5. Comparing subjective and objective measures of headgear compliance

    NARCIS (Netherlands)

    Bos, A.; Kleverlaan, C.J.; Hoogstraten, J.; Prahl-Andersen, B.; Kuitert, R.

    2007-01-01

    Introduction: Many studies have used subjective measures to examine patient compliance during orthodontic treatment. Objective measurement of compliance has been confined to only a few studies that used electronic timing devices built into removable appliances. Our aim in this study was to compare

  6. Simuluating quantum many-body systems subject to measurements

    DEFF Research Database (Denmark)

    Gammelmark, Søren

    We demonstrate how to simulate both discrete and continuous stochastic evolutions of a quantum many-body system subject to measurements using matrix product states. A particular, but generally applicable, measurement model is analyzed and a simple representation in terms of matrix product operators...

  7. Simulating quantum many-body systems subject to measurements

    DEFF Research Database (Denmark)

    Gammelmark, Søren

    We demonstrate how to simulate both discrete and continuous stochastic evolutions of a quantum many-body system subject to measurements using matrix product states. A particular, but generally applicable, measurement model is analyzed and a simple representation in terms of matrix product operators...

  8. Optimizing measurement of subjective amplitude of accommodation with defocus curves.

    Science.gov (United States)

    Gupta, Navneet; Wolffsohn, James S W; Naroo, Shehzad A

    2008-08-01

    To determine whether letter sequences and/or lens-presentation order should be randomized when measuring defocus curves and to assess the most appropriate criterion for calculating the subjective amplitude of accommodation (AoA) from defocus curves. Eye Clinic, School of Life & Health Sciences, Aston University, Birmingham, United Kingdom. Defocus curves (from +3.00 diopters [D] to -3.00 D in 0.50 D steps) for 6 possible combinations of randomized or nonrandomized letter sequences and/or lens-presentation order were measured in a random order in 20 presbyopic subjects. Subjective AoA was calculated from the defocus curves by curve fitting using various published criteria, and each was correlated to subjective push-up AoA. Objective AoA was measured for comparison of blur tolerance and pupil size. Randomization of lens-presentation order and/or letter sequences, or lack of, did not affect the measured defocus curves (P >.05, analysis of variance). The range of defocus that maintains highest achievable visual acuity (allowing for variability of repeated measurement) was better correlated to (r = 0.84) and agreed best with (+/-0.50 D) subjective push-up AoA than any other relative or absolute acuity criterion used in previous studies. Nonrandomized letters and lens presentation on their own did not affect subjective AoA measured by defocus curves, although their combination should be avoided. Quantification of subjective AoA from defocus curves should be standardized to the range of defocus that maintains the best achievable visual acuity.

  9. Subjective Sleep Measures in Children: Self-Report.

    Science.gov (United States)

    Erwin, Andrea M; Bashore, Lisa

    2017-01-01

    The American Academy of Sleep Medicine (AASM) recently published a consensus statement on the recommended number of hours of sleep in infants and children. The AASM expert panel identified seven health categories in children influenced by sleep duration, a component of sleep quality. For optimal health and general function, children require a certain number of hours of sleep each night. Limited data exist to subjectively assess sleep in this population. Practitioners must evaluate overall sleep quality not simply sleep duration. The purpose of this article is to provide a mini-review of the self-report sleep measures used in children. The authors individually completed a review of the literature for this article via an independent review followed by collaborative discussion. The subjective measures included in this mini-review have been used in children, but not all measures have reported psychometrics. Several tools included in this mini-review measure subjective sleep in children but with limited reliabilities or only preliminary psychometrics. Accurate measurement of self-reported sleep in children is critical to identify sleep problems in this population and further detect associated health problems. Ongoing studies are warranted to establish reliable and valid measures of self-reported sleep in children to accurately detect health problems associated with poor sleep quality. This mini-review of the literature is an important first step to identify the most reliable subjective sleep measures in children.

  10. A measure of subjective happiness: Preliminary reliability and construct validation

    OpenAIRE

    Lyubomirsky, S; Lepper, HS

    1999-01-01

    Using a 'subjectivist' approach to the assessment of happiness, a new 4-item measure of global subjective happiness was developed and validated in 14 studies with a total of 2 732 participants. Data was collected in the United States from students on two college campuses and one high school campus, from community adults in two California cities, and from older adults. Students and community adults in Moscow, Russia also participated in this research. Results indicated that the Subjective Happ...

  11. On the relationship between subjective and objective measures of fatigue.

    Science.gov (United States)

    Völker, Ina; Kirchner, Christine; Bock, Otmar Leo

    2016-09-01

    Objective and subjective methods have been used in the past to assess workplace fatigue, but little is known about correlations between them. We examine correlations between subjective and objective measures, including measures collected in a workplace scenario. 15 young and 17 older participants were assessed before and after work with four types of fatigue measure: objective physical (posturography), objective mental (psychomotor vigilance task), subjective physical and mental (self-assessment), objective and subjective realistic (oculomotor behaviour, observer-rated facial expression, typing performance). Pre- and post-test scores were analysed with an ANOVA, significant differences were submitted to a factor analysis. It yielded three factors: one representing posturography, the second self-rated mental and physical fatigue and the third observer-rated facial expression. Results advocate the existence of three independent fatigue components: Objective physical fatigue, introspective and extrospective fatigue. Practitioner Summary: This study analyses correlations between different subjective and objective fatigue markers to better understand the complex nature of workplace fatigue. Measurements were conducted directly at the workplace. Results reveal that fatigue comprises three independent fatigue components: Objective physical fatigue, introspective and extrospective fatigue.

  12. Comparing perceptual judgment and subjective measures of spatial awareness.

    Science.gov (United States)

    Bolton, Matthew L; Bass, Ellen J

    2009-07-01

    Spatial awareness is important in domains where safety hinges on human operators keeping track of the relative locations of objects in the environment. While a variety of subjective and judgment-based measures have been used to evaluate spatial awareness, none have probed all three of its levels: (1) identification of environmental objects, (2) their current locations relative to the operator, and (3) their relative positions over time. This work compares new judgment-based measures of spatial awareness that probe all three levels of spatial awareness to conventional subjective measures. In the evaluation of 14 configurations of Synthetic Vision Systems head down displays (seven terrain textures and two Geometric Fields of View (GFOVs)), 18 pilots made four types of judgments (relative angle, distance, height, and abeam time) regarding the location of terrain points displayed in 112 5-s, non-interactive simulations. They also provided subjective demand, awareness, clutter, SA-SWORD, and preferred GFOV measures. Correlation analyses revealed that displays that received higher awareness and SA-SWORD subjective ratings were associated with smaller errors in abeam time judgments and, for SA-SWORD, smaller errors in relative distance judgments. Thus SA-SWORD provides insight into level 2 spatial awareness and both SA-SWORD and awareness provide insight into level 3 spatial awareness. ANOVA and chi(2) analyses revealed comparable results between display configurations that produced the minimum error in judgments and those recommended by the awareness, SA-SWORD, and preferred GFOV measures.

  13. Reproducibility of single-subject functional connectivity measurements.

    Science.gov (United States)

    Anderson, J S; Ferguson, M A; Lopez-Larson, M; Yurgelun-Todd, D

    2011-03-01

    Measurements of resting-state functional connectivity have increasingly been used for characterization of neuropathologic and neurodevelopmental populations. We collected data to characterize how much imaging time is necessary to obtain reproducible quantitative functional connectivity measurements needed for a reliable single-subject diagnostic test. We obtained 100 five-minute BOLD scans on a single subject, divided into 10 sessions of 10 scans each, with the subject at rest or while watching video clips of cartoons. These data were compared with resting-state BOLD scans from 36 healthy control subjects by evaluating the correlation between each pair of 64 small spheric regions of interest obtained from a published functional brain parcellation. Single-subject and group data converged to reliable estimates of individual and population connectivity values proportional to 1 / sqrt(n). Dramatic improvements in reliability were seen by using ≤25 minutes of imaging time, with smaller improvements for additional time. Functional connectivity "fingerprints" for the individual and population began diverging at approximately 15 minutes of imaging time, with increasing reliability even at 4 hours of imaging time. Twenty-five minutes of BOLD imaging time was required before any individual connections could reliably discriminate an individual from a group of healthy control subjects. A classifier discriminating scans during which our subject was resting or watching cartoons was 95% accurate at 10 minutes and 100% accurate at 15 minutes of imaging time. An individual subject and control population converged to reliable different functional connectivity profiles that were task-modulated and could be discriminated with sufficient imaging time.

  14. Objective and subjective measures of vergence step responses.

    Science.gov (United States)

    Jainta, S; Hoormann, J; Jaschinski, W

    2007-12-01

    Dichoptic nonius lines are used for subjectively (psychophysically) measuring vergence states, but they have been questioned as valid indicators of vergence eye position. In a mirror-stereoscope, we presented convergent and divergent step-stimuli and estimated the vergence response with nonius lines flashed at fixed delays after the disparity step stimulus. For each delay, an adaptive psychophysical procedure was run to determine the physical nonius offset required for subjective alignment; these vergence states were compared with objective eye movement recordings. Between both measures of initial vergence, we calculated the maximal cross-correlation coefficient: the median in our sample was about 0.9 for convergence and divergence, suggesting a good agreement. Relative to the objective measures, the subjective method revealed a smaller vergence velocity and a larger vergence response in the final phase of the response, but both measures were well correlated. The dynamic nonius test is therefore considered to be useful to relatively evaluate a subject's ability in disparity vergence.

  15. Vehicle handling: relationships between subjective and objective measures

    NARCIS (Netherlands)

    Verschuren, R.M.A.F.; Hogema, J.H.

    2003-01-01

    TNO Human Factors and TNO Automotive are investigating relationships between subjective and objective measures in the area of vehicle handling. This paper presents a driving simulator study and a field experiment in which these relationships were investigated. First, in the driving simulator

  16. Comparing objective and subjective error measures for color constancy

    NARCIS (Netherlands)

    Lucassen, M.P.; Gijsenij, A.; Gevers, T.

    2008-01-01

    We compare an objective and a subjective performance measure for color constancy algorithms. Eight hyper-spectral images were rendered under a neutral reference illuminant and four chromatic illuminants (Red, Green, Yellow, Blue). The scenes rendered under the chromatic illuminants were color

  17. Subjective Quality Measurement of Speech Its Evaluation, Estimation and Applications

    CERN Document Server

    Kondo, Kazuhiro

    2012-01-01

    It is becoming crucial to accurately estimate and monitor speech quality in various ambient environments to guarantee high quality speech communication. This practical hands-on book shows speech intelligibility measurement methods so that the readers can start measuring or estimating speech intelligibility of their own system. The book also introduces subjective and objective speech quality measures, and describes in detail speech intelligibility measurement methods. It introduces a diagnostic rhyme test which uses rhyming word-pairs, and includes: An investigation into the effect of word familiarity on speech intelligibility. Speech intelligibility measurement of localized speech in virtual 3-D acoustic space using the rhyme test. Estimation of speech intelligibility using objective measures, including the ITU standard PESQ measures, and automatic speech recognizers.

  18. How Objective Are Subjective Measures of Organizational Innovativeness, Really?

    Directory of Open Access Journals (Sweden)

    Patrycja Klimas

    2014-06-01

    Full Text Available Purpose: This paper aims to match subjective and objective measures of organizational innovativeness and test correlative relationship between the two. Methodology: The research adopts a quantitative approach, and applies correlation analysis to identify interdependencies. The study has been done in the aviation industry, as organizational innovativeness has so far been described especially in high-tech industries – however it has not been investigated within aviation industry yet. Findings: The results show that the discussions over reliability of research based on subjective measurements techniques are not unfounded. The evidence suggests that subjective measures are not correlated with objective measures, and the outcomes of third-party investigations differ considerably. Therefore decisions about measurements techniques should be deliberate, thought out, theoretically grounded and justifi ed. In general, methodological recommendations provided by this paper could be boiled down to the ascertainment that accurate and reliable assessment of organizational innovativeness should use a set of objective measures addressing all stages of the innovation process. Originality: It should be noted that this study was restricted to only one industry and prone to some common bias. The aviation industry sample was relatively small and purposefully selected, disallowing conclusive statements made outside of this empirical setting. However despite the limitations this paper provides some significant contribution to evaluation and research on innovativeness. It compares two approaches to measurement and empirically proves which approach is more suitable in case of such a highly innovation-intensive sector like aviation. Moreover, it introduces a new in Polish research tool for subjective assessment of organizational innovativeness namely the questionnaire developed by Wang and Ahmed (2004.

  19. Using theta and alpha band power to assess cognitive workload in multitasking environments.

    Science.gov (United States)

    Puma, Sébastien; Matton, Nadine; Paubel, Pierre-V; Raufaste, Éric; El-Yagoubi, Radouane

    2017-10-07

    Cognitive workload is of central importance in the fields of human factors and ergonomics. A reliable measurement of cognitive workload could allow for improvements in human machine interface designs and increase safety in several domains. At present, numerous studies have used electroencephalography (EEG) to assess cognitive workload, reporting the rise in cognitive workload to be associated with increases in theta band power and decreases in alpha band power. However, results have been inconsistent with some failing to reach the required level of significance. We hypothesized that the lack of consistency could be related to individual differences in task performance and/or to the small sample sizes in most EEG studies. In the present study we used EEG to assess the increase in cognitive workload occurring in a multitasking environment while taking into account differences in performance. Twenty participants completed a task commonly used in airline pilot recruitment, which included an increasing number of concurrent sub-tasks to be processed from one to four. Subjective ratings, performances scores, pupil size and EEG signals were recorded. Results showed that increases in EEG alpha and theta band power reflected increases in the involvement of cognitive resources for the completion of one to three subtasks in a multitasking environment. These values reached a ceiling when performances dropped. Consistent differences in levels of alpha and theta band power were associated to levels of task performance: highest performance was related to lowest band power. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. The Measurement of Pilot Workload.

    Science.gov (United States)

    1983-01-01

    visual display system. It is mounted on a motion platform having two degrees of freedom and is able to provide vestibular and kinesthetic pilot cueing...I. . . . . .. . APPENDIX C-I MANEUVERS BRIEFING (TRAINING/SCREENING OF PILOTS) NORMAL TAKEOFF At Vr , rotate to 100 - 120. When a positive rate of

  1. The Power Dynamics and Politics of Survey Design: Measuring Workload Associated with Teaching, Administering and Supporting Work-Integrated Learning Courses

    Science.gov (United States)

    Clark, Lindie; Rowe, Anna; Cantori, Alex; Bilgin, Ayse; Mukuria, Valentine

    2016-01-01

    Work-integrated learning (WIL) courses can be more time consuming and resource intensive to design, teach, administer and support than classroom-based courses, as they generally require different curricula and pedagogical approaches as well as additional administrative and pastoral responsibilities. Workload and resourcing issues are reported as…

  2. Family Medicine in Croatia: Quality Measured by Patients’ Subjective Satisfaction

    OpenAIRE

    Stanić, Arsen; Stevanović, Ranko; Pristaš, Ivan; Tiljak, Hrvoje; Benković, Vanesa; Krčmar, Nevenka; Jovanović, Aleksandar; Jurlina, Nataša; Nott, Teodora

    2007-01-01

    A survey of the subjective assessment of quality in the fi eld of family medicine was conducted on a random sample of 50 family medicine teams distributed proportionally across all Croatian counties, and both rural and urban areas. It measured the satisfaction of insurants/patients, i.e. healthcare service users, on the basis of the completed EUROPEP questionnaire. The survey included 7.271 respondents (the response rate to 15.000 distributed questionnaires was 48.47%). O...

  3. Quantifying the impact of cross coverage on physician's workload and performance in radiation oncology.

    Science.gov (United States)

    Mosaly, Prithima R; Mazur, Lukasz M; Jones, Ellen L; Hoyle, Lesley; Zagar, Timothy; Chera, Bhishamjit S; Marks, Lawrence B

    2013-01-01

    To quantitatively assess the difference in workload and performance of radiation oncology physicians during radiation therapy treatment planning tasks under the conditions of "cross coverage" versus planning a patient with whom they were familiar. Eight physicians (3 experienced faculty physicians and 5 physician residents) performed 2 cases. The first case represented a "cross-coverage" scenario where the physicians had no prior information about the case to be planned. The second exposure represented a "regular-coverage" scenario where the physicians were familiar with the patient case to be planned. Each case involved 3 tasks to be completed systematically. Workload was assessed both subjectively (perceived) using National Aeronautics and Space Administration-Task Load Index (NASA-TLX), and objectively (physiological) throughout the task using eye data (via monitoring pupil size and blink rate). Performance of each task and the case was measured using completion time. Subjective willingness to approve or disapprove the generated plan was obtained after completion of the case only. Forty-eight perceived and 48 physiological workload assessments were obtained. Overall, results revealed a significant increase in perceived workload (high NASA-TLX score) and decrease in performance (longer completion time and reduced approval rate) during cross coverage. There were nonsignificant increases in pupil diameter and decreases in the blink rate during cross-coverage versus regular-coverage scenario. In both cross-coverage and regular-coverage scenarios the level of experience did not affect workload and performance. The cross-coverage scenario significantly increases perceived workload and degrades performance versus regular coverage. Hence, to improve patient safety, efforts must be made to develop policies, standard operating procedures, and usability improvements to electronic medical record and treatment planning systems for "easier" information processing to deal with

  4. Strategic workload management and decision biases in aviation

    Science.gov (United States)

    Raby, Mireille; Wickens, Christopher D.

    1994-01-01

    Thirty pilots flew three simulated landing approaches under conditions of low, medium, and high workload. Workload conditions were created by varying time pressure and external communications requirements. Our interest was in how the pilots strategically managed or adapted to the increasing workload. We independently assessed the pilot's ranking of the priority of different discrete tasks during the approach and landing. Pilots were found to sacrifice some aspects of primary flight control as workload increased. For discrete tasks, increasing workload increased the amount of time in performing the high priority tasks, decreased the time in performing those of lowest priority, and did not affect duration of performance episodes or optimality of scheduling of tasks of any priority level. Individual differences analysis revealed that high-performing subjects scheduled discrete tasks earlier in the flight and shifted more often between different activities.

  5. Executive function in fibromyalgia: Comparing subjective and objective measures.

    Science.gov (United States)

    Gelonch, Olga; Garolera, Maite; Valls, Joan; Rosselló, Lluís; Pifarré, Josep

    2016-04-01

    There is evidence to suggest the existence of an executive dysfunction in people diagnosed with fibromyalgia, although there are certain inconsistencies between studies. Here, we aim to compare executive performance between patients with fibromyalgia and a control group by using subjective and objective cognitive tests, analyzing the influence of patient mood on the results obtained, and studying associations between the two measures. 82 patients diagnosed with fibromyalgia and 42 healthy controls, matched by age and years of education, were assessed using the Behavioral Rating Inventory of Executive Function - Adult Version (BRIEF-A) as a subjective measure of executive functioning. A selection of objective cognitive tests were also used to measure a series of executive functions and to identify symptoms of depression and anxiety. Patients with fibromyalgia perceived greater difficulties than the control group on all of the BRIEF-A scales. However, after adjustments were made for depression and anxiety the only differences that remained were those associated with the working memory scale and the Metacognition and Global Executive Composite index. In the case of the objective cognitive tests, a significantly worse overall performance was evidenced for the fibromyalgia patients. However, this also disappeared when adjustments were made for depression and anxiety. After this adjustment, fibromyalgia patients only performed significantly worse for the interference effect in the Stroop Test. Although there were no significant associations between most of the objective cognitive tests and the BRIEF-A scales, depression and anxiety exhibited strong associations with almost all of the BRIEF-A scales and with several of the objective cognitive tests. Patients with fibromyalgia showed executive dysfunction in subjective and objective measures, although most of this impairment was associated with mood disturbances. Exceptions to this general rule were observed in the

  6. WBDOC Weekly Workload Status Report

    Data.gov (United States)

    Social Security Administration — Weekly reports of workloads processed in the Wilkes Barre Data Operation Center. Reports on quantities of work received, processed, pending and average processing...

  7. Subjective relevance of objective measures for spatial impression (A)

    DEFF Research Database (Denmark)

    Wang, Lily M.; Gade, Anders Christian

    2000-01-01

    Several objective measures have been proposed to describe the feeling of spatial impression in concert halls, including Lateral Energy Fraction (LF) and Interaural Cross-Correlation Coefficient (IACC). However, previous studies have shown that LF and IACC values did not highly correlate with each...... generated by the room acoustics simulation program ODEON, using four different musical motifs, and were presented to test subjects via headphones. Results from the experiments are presented. [Work supported by ASA Hunt Postdoctoral Research Fellowship.]...... other at individual seat positions in real halls [J. S. Bradley, J. Acoust. Soc. Am. 96, 3525–3535 (1994)]. To investigate the listener envelopment aspect of spatial impression further, subjective paired-comparison tests have been run using signals which have various values for LF, early IACC (from 5...

  8. Measuring trade-offs that matter: assessing the impact of a new electronic cross-match policy on the turnaround time and the cross-match workload efficiency.

    Science.gov (United States)

    Lin, David M; Goldfinger, Dennis; Lu, Qun; Wallace, Bridget; Kosaka-Nguyen, Dawn; Wood, Alisa; Porter, Bethany; Bumerts, Pamela; Jeffery, Rebecca; Fang, Amy; Stalcup, Irene; Penaflorida, Tracy; Ziman, Alyssa

    2014-12-01

    Our traditional cross-match (XM) policy generated a significant number of XM units that were never issued. To minimize the unnecessary XM workload, we proposed a new policy where orders eligible for the electronic XM (EXM) are pended until orders to issue red blood cells (RBCs) are received. To address concerns that this new policy might unduly delay blood availability, we conducted a study to assess whether the new policy was noninferior to the traditional policy with regard to the turnaround time (TAT). We monitored the TAT and XM workload efficiency (XM-to-issue [C : I] ratio) for a total of 8 weeks split between the two policies' periods. The primary outcome was the proportion of RBC issue requests that was turned around in less than 12 minutes. Fifty percent (1133 of 2265) of issue requests were turned around in 12 minutes or less under the traditional policy compared to 43.9% (975 of 2223) under the new policy (absolute difference of 6.1%; 95% confidence interval [CI], 3.2%-9.1%; p trade-off between delays in the TAT and efficiency gains in the XM workload remained acceptable for patient care. © 2014 AABB.

  9. Workload Control with Continuous Release

    NARCIS (Netherlands)

    Phan, B. S. Nguyen; Land, M. J.; Gaalman, G. J. C.

    2009-01-01

    Workload Control (WLC) is a production planning and control concept which is suitable for the needs of make-to-order job shops. Release decisions based on the workload norms form the core of the concept. This paper develops continuous time WLC release variants and investigates their due date

  10. Application of Avatars in Display Design to Support Spatial Awareness under Varying Workload Conditions

    Science.gov (United States)

    2006-09-01

    AVATARS IN DISPLAY DESIGN TO SUPPORT SPATIAL AWARENESS UNDER VARYING WORKLOAD CONDITIONS by Dimitrios Myttas September 2006 Thesis Advisor...Avatars in Display Design to Support Spatial Awareness under Varying Workload Conditions 6. AUTHOR(S) Dimitrios Myttas 5. FUNDING NUMBERS 7...24 5. Human Performance – Workload Measurement ................. 24 III. PROPOSED DISPLAY DESIGN ................................................................... 27

  11. Nursing Workload and the Changing Health Care Environment: A Review of the Literature

    Science.gov (United States)

    Neill, Denise

    2011-01-01

    Changes in the health care environment have impacted nursing workload, quality of care, and patient safety. Traditional nursing workload measures do not guarantee efficiency, nor do they adequately capture the complexity of nursing workload. Review of the literature indicates nurses perceive the quality of their work has diminished. Research has…

  12. Subjectivity

    Directory of Open Access Journals (Sweden)

    Jesús Vega Encabo

    2015-11-01

    Full Text Available In this paper, I claim that subjectivity is a way of being that is constituted through a set of practices in which the self is subject to the dangers of fictionalizing and plotting her life and self-image. I examine some ways of becoming subject through narratives and through theatrical performance before others. Through these practices, a real and active subjectivity is revealed, capable of self-knowledge and self-transformation. 

  13. Psychological workload and body weight

    DEFF Research Database (Denmark)

    Overgaard, Dorthe; Gyntelberg, F; Heitmann, B L

    2004-01-01

    BACKGROUND: According to Karasek's Demand/Control Model, workload can be conceptualized as job strain, a combination of psychological job demands and control in the job. High job strain may result from high job demands combined with low job control. Aim To give an overview of the literature...... on the association between obesity and psychological workload. METHOD: We carried out a review of the associations between psychological workload and body weight in men and women. In total, 10 cross-sectional studies were identified. RESULTS: The review showed little evidence of a general association between...... psychological workload and body mass index. Only weak positive associations were found, and only between elements of psychological workload and overall body weight. For body fat distribution, two out of three studies showed a positive association in men, but the associations became insignificant after...

  14. The Effect of Communication Style on Task Performance and Mental Workload Using Wearable Computers

    OpenAIRE

    Nash, Eric B

    2000-01-01

    This thesis measured the mental workload associated with operating a voice activated software application run on wearable computer under five different communication styles (buttons, command line, icon buttons, icon text menus, and text menus). The goal of this thesis was to determine which communication style would be best allow wearable computer users to simultaneously perform other non-computer tasks. Thirty subjects were randomly assigned to using one of five software versions (n = 6), ...

  15. Avaliação da carga mental de trabalho e do desempenho de medidas de mensuração: NASA TLX e SWAT Evaluation of mental workload and performance measurement: NASA TLX and SWAT

    Directory of Open Access Journals (Sweden)

    Mariane de Souza Cardoso

    2012-12-01

    Full Text Available Este estudo avalia a carga mental para atividades desempenhadas em empresa catarinense de soluções em energia e busca comparar os resultados da carga mental de trabalho encontrada a partir de dois métodos de mensuração atualmente mais usados - NASA TLX e SWAT. Por meio deste estudo avaliou-se a carga mental exigida tanto pela atividade de montagem manual, quanto de montagem automática de placas eletrônicas. Os resultados da avaliação da carga mental evidenciaram que entre as duas formas de execução da atividade, as exigências mentais mostram-se maiores na atividade de montagem manual. Os métodos de avaliação da carga mental aplicados em estudos da ergonomia possibilitam conhecer as capacidades e limitações do trabalhador, características da organização do trabalho e facilitam a apresentação quantitativa e qualitativa dos resultados. A comparação do desempenho entre os dois métodos de avaliação da carga mental, também se mostrou como uma investigação pertinente para o campo da ergonomia, já que são poucos os estudos comparativos em relação ao desempenho dos métodos. Na comparação do desempenho geral entre os dois métodos, o método NASA TLX possibilita avaliar a carga mental analisando diversas dimensões da situação de trabalho e apresenta vantagens quando comparado ao SWAT, pois pode ser facilmente aplicado e mostrou-se com maior aceitação por parte dos avaliados.This study evaluates the mental workload in some activities in an electricity generation company in Santa Catarina, Brazil and compares the mental workload measurements obtained using two commonly used measurement methods- NASA TLX and SWAT. The mental workload required by both manual and automated assembly of circuit boards was evaluated. The evaluation of the mental workload showed that comparing these two types of activities, the mental requirements appear to be higher during manual assembly tasks. The methods for assessing the mental

  16. Crew workload-management strategies - A critical factor in system performance

    Science.gov (United States)

    Hart, Sandra G.

    1989-01-01

    This paper reviews the philosophy and goals of the NASA/USAF Strategic Behavior/Workload Management Program. The philosophical foundation of the program is based on the assumption that an improved understanding of pilot strategies will clarify the complex and inconsistent relationships observed among objective task demands and measures of system performance and pilot workload. The goals are to: (1) develop operationally relevant figures of merit for performance, (2) quantify the effects of strategic behaviors on system performance and pilot workload, (3) identify evaluation criteria for workload measures, and (4) develop methods of improving pilots' abilities to manage workload extremes.

  17. Measuring Subjective Happiness by Newly Developed Scale in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Kambiz Abachizadeh

    2015-10-01

    Full Text Available Background: Happiness as one of the main positive health indicators has drawn more attention in recent years among policy makers and health system managers. There are few studies performed to measure happiness in population-based settings in Iran. In response to this need, our study tends to assess Iranians subjective happiness in Tehran, Capital city of Iran.Materials and Methods: Present study was conducted in Tehran, Capital of Iran, with more than 7 Million populations in January 2013, using a two-step approach. In first step c conceptual framework of Iranians’ happiness was developed. In the second phase of study, a survey recruiting 700 participants was conducted. Stratified cluster sampling method was employed. Participants were recruited from all the 22 municipal divisions of Tehran as strata, proportional to the population size and its gender and age distribution. Happiness was measure by a 40-item questionnaire with scores ranged among 40 to 200.Results: Conceptual framework of Iranians’ happiness based on reviewed documents and consensus building process was the product of first step. At second step, from a pool of 700 persons, 696 (97% agreed to participate and filled out the questionnaire completely.  The mean of happiness score was 143.9 (95% confidence interval, 142.5 to 145.4. The results show that the happiness score of jobless people (135.1, 95%CI: 128.1-142.0 and widowed singles (126.6, 95%CI: 113.0-140.2 were significantly lower than other corresponding groups. There was no significant association between gender, age group, educational level as determinants and happiness.Conclusion: Happiness level of Tehranians is somewhat higher than the moderate level. This finding is consistent with findings of other conducted studies in country. However, it is not consistent with some of international reports of happiness, For instance, Happy Planet Index. Due to inadequate information, it is necessary to conduct more research to

  18. Physical Workload and Work Capacity across Occupational Groups.

    Directory of Open Access Journals (Sweden)

    Stefanie Brighenti-Zogg

    Full Text Available This study aimed to determine physical performance criteria of different occupational groups by investigating physical activity and energy expenditure in healthy Swiss employees in real-life workplaces on workdays and non-working days in relation to their aerobic capacity (VO2max. In this cross-sectional study, 337 healthy and full-time employed adults were recruited. Participants were classified (nine categories according to the International Standard Classification of Occupations 1988 and merged into three groups with low-, moderate- and high-intensity occupational activity. Daily steps, energy expenditure, metabolic equivalents and activity at different intensities were measured using the SenseWear Mini armband on seven consecutive days (23 hours/day. VO2max was determined by the 20-meter shuttle run test. Data of 303 subjects were considered for analysis (63% male, mean age: 33 yrs, SD 12, 101 from the low-, 102 from the moderate- and 100 from the high-intensity group. At work, the high-intensity group showed higher energy expenditure, metabolic equivalents, steps and activity at all intensities than the other groups (p<0.001. There were no significant differences in physical activity between the occupational groups on non-working days. VO2max did not differ across groups when stratified for gender. The upper workload limit was 21%, 29% and 44% of VO2max in the low-, moderate- and high-intensity group, respectively. Men had a lower limit than women due to their higher VO2max (26% vs. 37%, when all groups were combined. While this study did confirm that the average workload limit is one third of VO2max, it showed that the average is misrepresenting the actual physical work demands of specific occupational groups, and that it does not account for gender-related differences in relative workload. Therefore, clinical practice needs to consider these differences with regard to a safe return to work, particularly for the high-intensity group.

  19. Biases and power for groups comparison on subjective health measurements.

    Directory of Open Access Journals (Sweden)

    Jean-François Hamel

    Full Text Available Subjective health measurements are increasingly used in clinical research, particularly for patient groups comparisons. Two main types of analytical strategies can be used for such data: so-called classical test theory (CTT, relying on observed scores and models coming from Item Response Theory (IRT relying on a response model relating the items responses to a latent parameter, often called latent trait. Whether IRT or CTT would be the most appropriate method to compare two independent groups of patients on a patient reported outcomes measurement remains unknown and was investigated using simulations. For CTT-based analyses, groups comparison was performed using t-test on the scores. For IRT-based analyses, several methods were compared, according to whether the Rasch model was considered with random effects or with fixed effects, and the group effect was included as a covariate or not. Individual latent traits values were estimated using either a deterministic method or by stochastic approaches. Latent traits were then compared with a t-test. Finally, a two-steps method was performed to compare the latent trait distributions, and a Wald test was performed to test the group effect in the Rasch model including group covariates. The only unbiased IRT-based method was the group covariate Wald's test, performed on the random effects Rasch model. This model displayed the highest observed power, which was similar to the power using the score t-test. These results need to be extended to the case frequently encountered in practice where data are missing and possibly informative.

  20. Total Student Workload: Implications of the European Credit Transfer and Accumulation System for an Integrated, Problem-Based Medical Curriculum

    Directory of Open Access Journals (Sweden)

    Emad Nosair

    2017-12-01

    Discussion: Measuring student total workload in a problem-based program is important for evading the associated overload, and improving the quality of teaching and learning. Calculating student workload in an integrated problem-based curriculum is a challenge. Total student workload is the foundation for determination of the European Credit Transfer and Accumulation System units. Measuring unstructured student workload (or “out-of-class” learning time is an important component of total student workload. Assigning the European Credit Transfer and Accumulation System to problem-based programs improves its quality assurance, and has educational, curricular, and organizational impact. Therefore, student workload in such programs should be regularity monitored and evaluated.

  1. Labour intensity of guidelines may have a greater effect on adherence than GPs' workload

    Directory of Open Access Journals (Sweden)

    Westert Gert P

    2009-11-01

    Full Text Available Abstract Background Physicians' heavy workload is often thought to jeopardise the quality of care and to be a barrier to improving quality. The relationship between these has, however, rarely been investigated. In this study quality of care is defined as care 'in accordance with professional guidelines'. In this study we investigated whether GPs with a higher workload adhere less to guidelines than those with a lower workload and whether guideline recommendations that require a greater time investment are less adhered to than those that can save time. Methods Data were used from the Second Dutch National survey of General Practice (DNSGP-2. This nationwide study was carried out between April 2000 and January 2002. A multilevel logistic-regression analysis was conducted of 170,677 decisions made by GPs, referring to 41 Guideline Adherence Indicators (GAIs, which were derived from 32 different guidelines. Data were used from 130 GPs, working in 83 practices with 98,577 patients. GP-characteristics as well as guideline characteristics were used as independent variables. Measures include workload (number of contacts, hours spent on continuing medical education, satisfaction with available time, practice characteristics and patient characteristics. Outcome measure is an indicator score, which is 1 when a decision is in accordance with professional guidelines or 0 when the decision deviates from guidelines. Results On average, 66% of the decisions GPs made were in accordance with guidelines. No relationship was found between the objective workload of GPs and their adherence to guidelines. Subjective workload (measured on a five point scale was negatively related to guideline adherence (OR = 0.95. After controlling for all other variables, the variation between GPs in adherence to guideline recommendations showed a range of less than 10%. 84% of the variation in guideline adherence was located at the GAI-level. Which means that the differences in

  2. Exercise responsive genes measured in peripheral blood of women with chronic fatigue syndrome and matched control subjects.

    Science.gov (United States)

    Whistler, Toni; Jones, James F; Unger, Elizabeth R; Vernon, Suzanne D

    2005-03-24

    Chronic fatigue syndrome (CFS) is defined by debilitating fatigue that is exacerbated by physical or mental exertion. To search for markers of CFS-associated post-exertional fatigue, we measured peripheral blood gene expression profiles of women with CFS and matched controls before and after exercise challenge. Women with CFS and healthy, age-matched, sedentary controls were exercised on a stationary bicycle at 70% of their predicted maximum workload. Blood was obtained before and after the challenge, total RNA was extracted from mononuclear cells, and signal intensity of the labeled cDNA hybridized to a 3800-gene oligonucleotide microarray was measured. We identified differences in gene expression among and between subject groups before and after exercise challenge and evaluated differences in terms of Gene Ontology categories. Exercise-responsive genes differed between CFS patients and controls. These were in genes classified in chromatin and nucleosome assembly, cytoplasmic vesicles, membrane transport, and G protein-coupled receptor ontologies. Differences in ion transport and ion channel activity were evident at baseline and were exaggerated after exercise, as evidenced by greater numbers of differentially expressed genes in these molecular functions. These results highlight the potential use of an exercise challenge combined with microarray gene expression analysis in identifying gene ontologies associated with CFS.

  3. Exercise responsive genes measured in peripheral blood of women with Chronic Fatigue Syndrome and matched control subjects

    Directory of Open Access Journals (Sweden)

    Unger Elizabeth R

    2005-03-01

    Full Text Available Abstract Background Chronic fatigue syndrome (CFS is defined by debilitating fatigue that is exacerbated by physical or mental exertion. To search for markers of CFS-associated post-exertional fatigue, we measured peripheral blood gene expression profiles of women with CFS and matched controls before and after exercise challenge. Results Women with CFS and healthy, age-matched, sedentary controls were exercised on a stationary bicycle at 70% of their predicted maximum workload. Blood was obtained before and after the challenge, total RNA was extracted from mononuclear cells, and signal intensity of the labeled cDNA hybridized to a 3800-gene oligonucleotide microarray was measured. We identified differences in gene expression among and between subject groups before and after exercise challenge and evaluated differences in terms of Gene Ontology categories. Exercise-responsive genes differed between CFS patients and controls. These were in genes classified in chromatin and nucleosome assembly, cytoplasmic vesicles, membrane transport, and G protein-coupled receptor ontologies. Differences in ion transport and ion channel activity were evident at baseline and were exaggerated after exercise, as evidenced by greater numbers of differentially expressed genes in these molecular functions. Conclusion These results highlight the potential use of an exercise challenge combined with microarray gene expression analysis in identifying gene ontologies associated with CFS.

  4. Electronic Health Record Alert-Related Workload as a Predictor of Burnout in Primary Care Providers.

    Science.gov (United States)

    Gregory, Megan E; Russo, Elise; Singh, Hardeep

    2017-07-05

    Electronic health records (EHRs) have been shown to increase physician workload. One EHR feature that contributes to increased workload is asynchronous alerts (also known as inbox notifications) related to test results, referral responses, medication refill requests, and messages from physicians and other health care professionals. This alert-related workload results in negative cognitive outcomes, but its effect on affective outcomes, such as burnout, has been understudied. To examine EHR alert-related workload (both objective and subjective) as a predictor of burnout in primary care providers (PCPs), in order to ultimately inform interventions aimed at reducing burnout due to alert workload. A cross-sectional questionnaire and focus group of 16 PCPs at a large medical center in the southern United States. Subjective, but not objective, alert workload was related to two of the three dimensions of burnout, including physical fatigue (p = 0.02) and cognitive weariness (p = 0.04), when controlling for organizational tenure. To reduce alert workload and subsequent burnout, participants indicated a desire to have protected time for alert management, fewer unnecessary alerts, and improvements to the EHR system. Burnout associated with alert workload may be in part due to subjective differences at an individual level, and not solely a function of the objective work environment. This suggests the need for both individual and organizational-level interventions to improve alert workload and subsequent burnout. Additional research should confirm these findings in larger, more representative samples.

  5. Full-time employed and a family caregiver: a profile of women's workload, effort, and health.

    Science.gov (United States)

    Juratovac, Evanne; Zauszniewski, Jaclene A

    2014-01-01

    Women provide care for elderly family members while managing their other responsibilities, including full-time employment. This descriptive study used an inductively derived workload-effort-health theoretical model to examine workload, effort, and health among 46 full-time employed family caregivers [CG] of community-dwelling older adults from a larger, nonprobability, cross-sectional sample of 110 CGs. The women's caregiving workload (time, difficulty, care recipient's [CR] function), effort (perceived exertion of energy experienced in doing a workload), self-assessed health [SAH], depressive symptoms, and sources of help were richly described, and several associations were found, including higher physical and mental effort, were significantly correlated with higher workload time and difficulty and lower CR function, but not SAH. Higher mental effort and workload, and poorer SAH were significantly correlated with high depressive symptoms. Worse effort, workload, and health experiences were reported by daughters and by women who lived with their CR; those who did not have family or formal caregiving help had higher mental effort and were more depressed, suggesting an area for further study. Suggestions are offered for richer measurement of employment status, caregiving workload, and effort. Findings provide a unique profile of full-time employed women CGs' workload, effort (that is, how they do the work), and health, toward a stronger understanding of how women manage multiple workloads. Workplace policies are needed to address workload, effort and health in this informal caregiving workforce. Copyright © 2014 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  6. Maintenance Models for Systems subject to Measurable Deterioration

    NARCIS (Netherlands)

    R.P. Nicolai (Robin)

    2008-01-01

    textabstractComplex engineering systems such as bridges, roads, flood defence structures, and power pylons play an important role in our society. Unfortunately such systems are subject to deterioration, meaning that in course of time their condition falls from higher to lower, and possibly even to

  7. Subjective sleepiness and sleep quality in adolescents are related to objective and subjective measures of school performance

    NARCIS (Netherlands)

    Boschloo, Annemarie; Krabbendam, Lydia; Dekker, Sanne; Lee, Nikki; De Groot, Renate; Jolles, Jelle

    2016-01-01

    This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11–18 years. Three subjective measures of sleep were used: sleepiness, sleep quality, and sleep duration. They were compared to three measures of school performance: objective school

  8. Subjective sleepiness and sleep quality in adolescents are related to objective and subjective measures of school performance

    NARCIS (Netherlands)

    Boschloo, Annemarie; Krabbendam, Lydia; Dekker, Sanne; Lee, Nikki; De Groot, Renate; Jolles, Jelle

    2018-01-01

    This study investigated the relation between sleep and school performance in a large sam- ple of 561 adolescents aged 11–18 years. Three subjective measures of sleep were used: sleepiness, sleep quality, and sleep duration. They were compared to three measures of school performance: objective school

  9. Subjective sleepiness and sleep quality in adolescents are related to objective and subjective measures of school performance

    NARCIS (Netherlands)

    Boschloo, A.; Krabbendam, L.; Dekker, S.; Lee, N.; Groot, R. de; Jolles, J.

    2013-01-01

    This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11-18 years. Three subjective measures of sleep were used: sleepiness, sleep quality, and sleep duration. They were compared to three measures of school performance: objective school

  10. Subjective Sleep Measures in Children: Self-Report

    OpenAIRE

    Erwin, Andrea M.; Bashore, Lisa

    2017-01-01

    The American Academy of Sleep Medicine (AASM) recently published a consensus statement on the recommended number of hours of sleep in infants and children. The AASM expert panel identified seven health categories in children influenced by sleep duration, a component of sleep quality. For optimal health and general function, children require a certain number of hours of sleep each night. Limited data exist to subjectively assess sleep in this population. Practitioners must evaluate overall sle...

  11. Measurement of tendon reflexes by surface electromyography in normal subjects

    NARCIS (Netherlands)

    Stam, J.; van Crevel, H.

    1989-01-01

    A simple method for measuring the tendon reflexes was developed. A manually operated, electronic reflex hammer was applied that enabled measurement of the strength of tendon taps. Reflex responses were recorded by surface electromyography. Stimulus-response relations and latencies of tendon reflexes

  12. Monitoring Workload in Throwing-Dominant Sports: A Systematic Review.

    Science.gov (United States)

    Black, Georgia M; Gabbett, Tim J; Cole, Michael H; Naughton, Geraldine

    2016-10-01

    used to monitor workload and purposes for monitoring workload, encompassing the relationship between workload and injury, individual responses to workloads, the effect of workload on subsequent performance and the future directions of workload-monitoring techniques. This systematic review highlighted a number of simple and effective workload-monitoring techniques implemented across a variety of throwing-dominant sports. The current literature placed an emphasis on the relationship between workload and injury. However, due to differences in chronological and training age, inconsistent injury definitions and time frames used for monitoring, injury thresholds remain unclear in throwing-dominant sports. Furthermore, although research has examined total workload, the intensity of workload is often neglected. Additional research on the reliability of self-reported workload data is also required to validate existing relationships between workload and injury. Considering the existing disparity within the literature, it is likely that throwing-dominant sports would benefit from the development of an automated monitoring tool to objectively assess throwing-related workloads in conjunction with well-established internal measures of load in athletes.

  13. Human interaction with robotic systems: performance and workload evaluations.

    Science.gov (United States)

    Reinerman-Jones, L; Barber, D J; Szalma, J L; Hancock, P A

    2017-10-01

    We first tested the effect of differing tactile informational forms (i.e. directional cues vs. static cues vs. dynamic cues) on objective performance and perceived workload in a collaborative human-robot task. A second experiment evaluated the influence of task load and informational message type (i.e. single words vs. grouped phrases) on that same collaborative task. In both experiments, the relationship of personal characteristics (attentional control and spatial ability) to performance and workload was also measured. In addition to objective performance and self-report of cognitive load, we evaluated different physiological responses in each experiment. Results showed a performance-workload association for directional cues, message type and task load. EEG measures however, proved generally insensitive to such task load manipulations. Where significant EEG effects were observed, right hemisphere amplitude differences predominated, although unexpectedly these latter relationships were negative. Although EEG measures were partially associated with performance, they appear to possess limited utility as measures of workload in association with tactile displays. Practitioner Summary: As practitioners look to take advantage of innovative tactile displays in complex operational realms like human-robotic interaction, associated performance effects are mediated by cognitive workload. Despite some patterns of association, reliable reflections of operator state can be difficult to discern and employ as the number, complexity and sophistication of these respective measures themselves increase.

  14. Curriculum Change Management and Workload

    Science.gov (United States)

    Alkahtani, Aishah

    2017-01-01

    This study examines the ways in which Saudi teachers have responded or are responding to the challenges posed by a new curriculum. It also deals with issues relating to workload demands which affect teachers' performance when they apply a new curriculum in a Saudi Arabian secondary school. In addition, problems such as scheduling and sharing space…

  15. Neurophysiologic monitoring of mental workload and fatigue during operation of a flight simulator

    Science.gov (United States)

    Smith, Michael E.; Gevins, Alan

    2005-05-01

    In one experiment, EEG recordings were made during a daytime session while 16 well-rested participants performed versions of a PC flight simulator task that were either low, moderate, or high in difficulty. In another experiment, the same subjects repeatedly performed high difficulty versions of the same task during an all night session with total sleep deprivation. Multivariate EEG metrics of cortical activation were derived for frontal brain regions essential for working memory and executive control processes that are presumably important for maintaining situational awareness, central brain regions essential for sensorimotor control, and posterior parietal and occipital regions essential for visuoperceptual processing. During the daytime session each of these regional measures displayed greater activation during the high difficulty task than during the low difficulty task, and degree of cortical activation was positively correlated with subjective workload ratings in these well-rested subjects. During the overnight session, cortical activation declined with time-on-task, and the degree of this decline over frontal regions was negatively correlated with subjective workload ratings. Since participants were already highly skilled in the task, such changes likely reflect fatigue-related diminishment of frontal executive capability rather than practice effects. These findings suggest that the success of efforts to gauge mental workload via proxy cortical activation measures in the context of adaptive automation systems will likely depend on use of user models that take both task demands and the operator"s state of alertness into account. Further methodological development of the measurement approach outlined here would be required to achieve a practical, effective objective means for monitoring transient changes in cognitive brain function during performance of complex real-world tasks.

  16. Subject bias in three self-report measures of change.

    NARCIS (Netherlands)

    Sprangers, M.; Hoogstraten, J.

    1991-01-01

    Examined whether 3 measures of self-reported change (post minus pre difference scores, post minus then difference scores, and direct improvement scores) are susceptible to training related S bias. 19 university students were assigned to a study planning (experimental) group, 19 to a text studying

  17. Subjective sleepiness and sleep quality in adolescents are related to objective and subjective measures of school performance

    OpenAIRE

    Annemarie eBoschloo; Lydia eKrabbendam; Sanne eDekker; Lee, Nikki C.; Renate ede Groot; Jelle eJolles

    2013-01-01

    This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11-18 years. Three subjective measures of sleep were used: sleepiness, sleep quality and sleep duration. They were compared to three measures of school performance: objective school grades, self-reported school performance, and parent-reported school performance. Sleepiness – ‘I feel sleepy during the first hours at school’ – appeared to predict both school grades and self-repor...

  18. Surgeons' display reduced mental effort and workload while performing robotically assisted surgical tasks, when compared to conventional laparoscopy.

    Science.gov (United States)

    Moore, Lee J; Wilson, Mark R; McGrath, John S; Waine, Elizabeth; Masters, Rich S W; Vine, Samuel J

    2015-09-01

    Research has demonstrated the benefits of robotic surgery for the patient; however, research examining the benefits of robotic technology for the surgeon is limited. This study aimed to adopt validated measures of workload, mental effort, and gaze control to assess the benefits of robotic surgery for the surgeon. We predicted that the performance of surgical training tasks on a surgical robot would require lower investments of workload and mental effort, and would be accompanied by superior gaze control and better performance, when compared to conventional laparoscopy. Thirty-two surgeons performed two trials on a ball pick-and-drop task and a rope-threading task on both robotic and laparoscopic systems. Measures of workload (the surgery task load index), mental effort (subjective: rating scale for mental effort and objective: standard deviation of beat-to-beat intervals), gaze control (using a mobile eye movement recorder), and task performance (completion time and number of errors) were recorded. As expected, surgeons performed both tasks more quickly and accurately (with fewer errors) on the robotic system. Self-reported measures of workload and mental effort were significantly lower on the robotic system compared to the laparoscopic system. Similarly, an objective cardiovascular measure of mental effort revealed lower investment of mental effort when using the robotic platform relative to the laparoscopic platform. Gaze control distinguished the robotic from the laparoscopic systems, but not in the predicted fashion, with the robotic system associated with poorer (more novice like) gaze control. The findings highlight the benefits of robotic technology for surgical operators. Specifically, they suggest that tasks can be performed more proficiently, at a lower workload, and with the investment of less mental effort, this may allow surgeons greater cognitive resources for dealing with other demands such as communication, decision-making, or periods of increased

  19. EEG-based Workload Estimation Across Affective Contexts

    Directory of Open Access Journals (Sweden)

    Christian eMühl

    2014-06-01

    Full Text Available Workload estimation from electroencephalographic signals (EEG offers a highly sensitive tool to adapt the human-computer interaction to the user state. To create systems that reliably work in the complexity of the real world, a robustness against contextual changes (e.g., mood, has to be achieved. To study the resilience of state-of-the-art EEG-based workload classification against stress we devise a novel experimental protocol, in which we manipulated the affective context (stressful/non-stressful while the participant solved a task with 2 workload levels. We recorded self-ratings, behavior, and physiology from 24 participants to validate the protocol. We test the capability of different, subject-specific workload classifiers using either frequency-domain, time-domain, or both feature varieties to generalize across contexts. We show that the classifiers are able to transfer between affective contexts, though performance suffers independent of the used feature domain. However, cross-context training is a simple and powerful remedy allowing the extraction of features in all studied feature varieties that are more resilient to task-unrelated variations in signal characteristics. Especially for frequency-domain features, across-context training is leading to a performance comparable to within-context training and testing. We discuss the significance of the result for neurophysiology-based workload detection in particular and for the construction of reliable passive brain-computer interfaces in general.

  20. Measuring Graph Literacy without a Test: A Brief Subjective Assessment.

    Science.gov (United States)

    Garcia-Retamero, Rocio; Cokely, Edward T; Ghazal, Saima; Joeris, Alexander

    2016-10-01

    Visual aids tend to help diverse and vulnerable individuals understand risk communications, as long as these individuals have a basic understanding of graphs (i.e., graph literacy). Tests of objective graph literacy (OGL) can effectively identify individuals with limited skills, highlighting vulnerabilities and facilitating custom-tailored risk communication. However, the administration of these tests can be time-consuming and may evoke negative emotional reactions (e.g., anxiety). To evaluate a brief and easy-to-use assessment of subjective graph literacy (SGL) (i.e., self-reported ability to process and use graphically presented information) and to estimate the robustness and validity of the SGL scale and compare it with the leading OGL scale in diverse samples from different cultures. Demographically diverse residents (n = 470) of the United States, young adults (n = 172) and patients (n = 175) from Spain, and surgeons (n = 175) from 48 countries. A focus group and 4 studies for instrument development and initial validation (study 1), reliability and convergent and discriminant validity evaluation (study 2), and predictive validity estimation (studies 3 and 4). Psychometric properties of the scale. In about 1 minute, the SGL scale provides a reliable, robust, and valid assessment of skills and risk communication preferences and evokes fewer negative emotional reactions than the OGL scale. The SGL scale can be suitable for use in clinical research and may be useful as a communication aid in clinical practice. Theoretical mechanisms involved in SGL, emerging applications, limitations, and open questions are discussed. © The Author(s) 2016.

  1. Air-to-ground training missions: a psychophysiological workload analysis.

    Science.gov (United States)

    Wilson, G F

    1993-09-01

    Psychophysiological measures are used to assess the workload of F4 Phantom aircraft pilots and weapon systems officers (WSOs) during air-to-ground training missions and during the performance of two levels of difficulty of a laboratory tracking task. The bombing range portion of the missions was associated with the highest pilot workload, while the WSO flying the aircraft was the highest workload segment for the WSOs. The pilots' data were found to have a wider range of values for the physiological measures than were found in the WSO data. The different levels of tracking task difficulty produced significant physiological effects but the range of values found for most of the flight segments were much greater. These data demonstrate that extrapolating laboratory data to the flight environment is risky at best. The various physiological measures were differentially sensitive to the different demands of the various flight segments.

  2. Effects of a psychophysiological system for adaptive automation on performance, workload, and the event-related potential P300 component

    Science.gov (United States)

    Prinzel, Lawrence J 3rd; Freeman, Frederick G.; Scerbo, Mark W.; Mikulka, Peter J.; Pope, Alan T.

    2003-01-01

    The present study examined the effects of an electroencephalographic- (EEG-) based system for adaptive automation on tracking performance and workload. In addition, event-related potentials (ERPs) to a secondary task were derived to determine whether they would provide an additional degree of workload specificity. Participants were run in an adaptive automation condition, in which the system switched between manual and automatic task modes based on the value of each individual's own EEG engagement index; a yoked control condition; or another control group, in which task mode switches followed a random pattern. Adaptive automation improved performance and resulted in lower levels of workload. Further, the P300 component of the ERP paralleled the sensitivity to task demands of the performance and subjective measures across conditions. These results indicate that it is possible to improve performance with a psychophysiological adaptive automation system and that ERPs may provide an alternative means for distinguishing among levels of cognitive task demand in such systems. Actual or potential applications of this research include improved methods for assessing operator workload and performance.

  3. Academic context and perceived mental workload of psychology students.

    Science.gov (United States)

    Rubio-Valdehita, Susana; López-Higes, Ramón; Díaz-Ramiro, Eva

    2014-01-01

    The excessive workload of university students is an academic stressor. Consequently, it is necessary to evaluate and control the workload in education. This research applies the NASA-TLX scale, as a measure of the workload. The objectives of this study were: (a) to measure the workload levels of a sample of 367 psychology students, (b) to group students according to their positive or negative perception of academic context (AC) and c) to analyze the effects of AC on workload. To assess the perceived AC, we used an ad hoc questionnaire designed according to Demand-Control-Social Support and Effort-Reward Imbalance models. Using cluster analysis, participants were classified into two groups (positive versus negative context). The differences between groups show that a positive AC improves performance (p < .01) and reduces feelings of overload (p < .02), temporal demand (p < .02), and nervousness and frustration (p < .001). Social relationships with peers and teachers, student autonomy and result satisfaction were relevant dimensions of the AC (p < .001 in all cases).

  4. Assessing and improving health in the workplace: an integration of subjective and objective measures with the STress Assessment and Research Toolkit (St.A.R.T. method

    Directory of Open Access Journals (Sweden)

    Panari Chiara

    2012-09-01

    Full Text Available Abstract Background The aim of this work was to introduce a new combined method of subjective and objective measures to assess psychosocial risk factors at work and improve workers’ health and well-being. In the literature most of the research on work-related stress focuses on self-report measures and this work represents the first methodology capable of integrating different sources of data. Method An integrated method entitled St.A.R.T. (STress Assessment and Research Toolkit was used in order to assess psychosocial risk factors and two health outcomes. In particular, a self-report questionnaire combined with an observational structured checklist was administered to 113 workers from an Italian retail company. Results The data showed a correlation between subjective data and the rating data of the observational checklist for the psychosocial risk factors related to work contexts such as customer relationship management and customer queue. Conversely, the factors related to work content (workload and boredom measured with different methods (subjective vs. objective showed a discrepancy. Furthermore, subjective measures of psychosocial risk factors were more predictive of workers’ psychological health and exhaustion than rating data. The different objective measures played different roles, however, in terms of their influence on the two health outcomes considered. Conclusions It is important to integrate self-related assessment of stressors with objective measures for a better understanding of workers’ conditions in the workplace. The method presented could be considered a useful methodology for combining the two measures and differentiating the impact of different psychological risk factors related to work content and context on workers’ health.

  5. Changes over time of psychoacoustic outcome measurements are not a substitute for subjective outcome measurements in acute tinnitus.

    Science.gov (United States)

    Rabau, Sarah; Cox, Tony; Punte, Andrea Kleine; Waelkens, Brecht; Gilles, Annick; Wouters, Kristien; de Varebeke, Sebastien Janssens; Van de Heyning, Paul

    2015-03-01

    The aim of this study was to assess correlations between the changes over time of various tinnitus measurements. A longitudinal prospective study comparing two test moments was performed: before treatment and after 90 days. Tinnitus assessment consisted of psychoacoustic outcome measurements (minimal masking level and loudness matching at 1 kHz) and subjective outcome measurements (Tinnitus Impairment Questionnaire, Tinnitus Questionnaire and Numeric Rating Scale of loudness and annoyance). Additionally, the effect size was measured. 35 subjects were included in this study. The subjects had a permanent, non-pulsatile tinnitus acquired psychoacoustic outcome measurements and ∆subjective outcome measurements. The effect size showed that subjective outcome measurements were the most responsive to measure change in tinnitus complaints. We can conclude that psychoacoustic outcome measurements of tinnitus cannot substitute subjective outcome measurements in patients with acute tinnitus. The authors recommend subjective outcome measurements as primary outcome measurements in a clinical setting. In research, however, it is meaningful to quantify tinnitus in both ways.

  6. Self-report scales alone cannot capture mental workload : A reply to De Winter, Controversy in human factors constructs and the explosive use of the NASA TLX: A measurement perspective

    NARCIS (Netherlands)

    de Waard, Dick; Lewis Evans, Ben

    Mental workload is an operational concept that can only be assessed indirectly. Self-reports such as the NASA-TLX however will never suffice to describe how a task was performed, and how heavily loaded operators were.

  7. Subjective Sleepiness and Sleep Quality in Adolescents are Related to Objective and Subjective Measures of School Performance

    OpenAIRE

    Boschloo, Annemarie; Krabbendam, Lydia; Dekker, Sanne; Lee, Nikki; De Groot, Renate; Jolles, Jelle

    2013-01-01

    This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11–18 years. Three subjective measures of sleep were used: sleepiness, sleep quality, and sleep duration. They were compared to three measures of school performance: objective school grades, self-reported school performance, and parent-reported school performance. Sleepiness – “I feel sleepy during the first hours at school” – appeared to predict both school grades and self-repo...

  8. A Procedure for Collecting Mental Workload Data During an Experiment That Is Comparable to IMPRINT Workload Data

    Science.gov (United States)

    2009-11-01

    workload by the individual’s level of certain physiological measures such as eye tracking, electrocardiogram ( EKG ), electro -encephalogram (EEG), and...galvanic skin response (GSR) measures. During the test, ATC evaluators instrumented two test participants and collected the EEG, EKG , and GSR data. They

  9. Monitoring the athlete training response: subjective self-reported measures trump commonly used objective measures: a systematic review.

    Science.gov (United States)

    Saw, Anna E; Main, Luana C; Gastin, Paul B

    2016-03-01

    Monitoring athlete well-being is essential to guide training and to detect any progression towards negative health outcomes and associated poor performance. Objective (performance, physiological, biochemical) and subjective measures are all options for athlete monitoring. We systematically reviewed objective and subjective measures of athlete well-being. Objective measures, including those taken at rest (eg, blood markers, heart rate) and during exercise (eg, oxygen consumption, heart rate response), were compared against subjective measures (eg, mood, perceived stress). All measures were also evaluated for their response to acute and chronic training load. The databases Academic search complete, MEDLINE, PsycINFO, SPORTDiscus and PubMed were searched in May 2014. Fifty-six original studies reported concurrent subjective and objective measures of athlete well-being. The quality and strength of findings of each study were evaluated to determine overall levels of evidence. Subjective and objective measures of athlete well-being generally did not correlate. Subjective measures reflected acute and chronic training loads with superior sensitivity and consistency than objective measures. Subjective well-being was typically impaired with an acute increase in training load, and also with chronic training, while an acute decrease in training load improved subjective well-being. This review provides further support for practitioners to use subjective measures to monitor changes in athlete well-being in response to training. Subjective measures may stand alone, or be incorporated into a mixed methods approach to athlete monitoring, as is current practice in many sport settings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Comparative analysis of cognitive tasks for modeling mental workload with electroencephalogram.

    Science.gov (United States)

    Hwang, Taeho; Kim, Miyoung; Hwangbo, Minsu; Oh, Eunmi

    2014-01-01

    Previous electroencephalogram (EEG) studies have shown that cognitive workload can be estimated by using several types of cognitive tasks. In this study, we attempted to characterize cognitive tasks that have been used to manipulate workload for generating classification models. We carried out a comparative analysis between two representative types of working memory tasks: the n-back task and the mental arithmetic task. Based on experiments with 7 healthy subjects using Emotiv EPOC, we compared the consistency, robustness, and efficiency of each task in determining cognitive workload in a short training session. The mental arithmetic task seems consistent and robust in manipulating clearly separable high and low levels of cognitive workload with less training. In addition, the mental arithmetic task shows consistency despite repeated usage over time and without notable task adaptation in users. The current study successfully quantifies the quality and efficiency of cognitive workload modeling depending on the type and configuration of training tasks.

  11. Reliability and minimal detectable change of a new treadmill-based progressive workload incremental test to measure cardiorespiratory fitness in manual wheelchair users.

    Science.gov (United States)

    Gauthier, Cindy; Arel, Jasmine; Brosseau, Rachel; Hicks, Audrey L; Gagnon, Dany H

    2017-11-01

    Cardiorespiratory fitness training is commonly provided to manual wheelchair users (MWUs) in rehabilitation and physical activity programs, emphasizing the need for a reliable task-specific incremental wheelchair propulsion test. Quantifying test-retest reliability and minimal detectable change (MDC) of key cardiorespiratory fitness measures following performance of a newly developed continuous treadmill-based wheelchair propulsion test (WPTTreadmill). Twenty-five MWUs completed the WPTTreadmill on two separate occasions within one week. During these tests, participants continuously propelled their wheelchair on a motorized treadmill while the exercise intensity was gradually increased every minute until exhaustion by changing the slope and/or speed according to a standardized protocol. Peak oxygen consumption (VO2peak), carbon dioxide production (VCO2peak), respiratory exchange ratio (RERpeak), minute ventilation (VEpeak) and heart rate (HRpeak) were computed. Time to exhaustion (TTE) and number of increments completed were also measured. Intra-class correlation coefficients (ICC) were calculated to determine test-retest reliability. Standard error of measurement (SEM) and MDC90% values were calculated. Excellent test-retest reliability was reached for almost all outcome measures (ICC=0.91-0.76), except for RERpeak (ICC=0.58), which reached good reliability. TTE (ICC=0.89) and number of increments (ICC=0.91) also reached excellent test-retest reliability. For the main outcome measures (VO2peak and TTE), absolute SEM was 2.27 mL/kg/min and 0.76 minutes, respectively and absolute MDC90% was 5.30 mL/kg/min and 1.77 minutes, respectively. The WPTTreadmill is a reliable test to assess cardiorespiratory fitness among MWUs. TTE and number of increments could be used as reliable outcome measures when VO2 measurement is not possible.

  12. Effects of speech versus tactile driver support messages on driving behaviour and workload

    NARCIS (Netherlands)

    Martens, M.H.; Winsum, W. van

    2001-01-01

    In a driving simulator experiment, effects were tested of an integrated support system on driving behaviour, user acceptance and workload. An alternative workload measure was used based upon peripheral vision. Two modes of support (tactile and speech messages) were compared to a control condition

  13. Of MOS and men : Bridging the gap between objective and subjective quality measurements in mobile TV

    NARCIS (Netherlands)

    De Koning, T.C.M.; Veldhoven, P.; Knoche, H.; Kooij, R.E.

    2007-01-01

    In this paper we explore the relation between subjective and objective measures of video quality. We computed objective MOS values from video clips using the video quality measuring tool VQM and compared it to the clips’ subjective Acceptability scores. Using the ITU defined mapping (M2G) from MOS

  14. The CMS workload management system

    Energy Technology Data Exchange (ETDEWEB)

    Cinquilli, M. [CERN; Evans, D. [Fermilab; Foulkes, S. [Fermilab; Hufnagel, D. [Fermilab; Mascheroni, M. [CERN; Norman, M. [UC, San Diego; Maxa, Z. [Caltech; Melo, A. [Vanderbilt U.; Metson, S. [Bristol U.; Riahi, H. [INFN, Perugia; Ryu, S. [Fermilab; Spiga, D. [CERN; Vaandering, E. [Fermilab; Wakefield, Stuart [Imperial Coll., London; Wilkinson, R. [Caltech

    2012-01-01

    CMS has started the process of rolling out a new workload management system. This system is currently used for reprocessing and Monte Carlo production with tests under way using it for user analysis. It was decided to combine, as much as possible, the production/processing, analysis and T0 codebases so as to reduce duplicated functionality and make best use of limited developer and testing resources. This system now includes central request submission and management (Request Manager), a task queue for parcelling up and distributing work (WorkQueue) and agents which process requests by interfacing with disparate batch and storage resources (WMAgent).

  15. E-MODULE DEVELOPMENT FOR THE SUBJECT OF MEASURING INSTRUMENTS AND MEASUREMENT IN ELECTRONICS ENGINEERING EDUCATION

    Directory of Open Access Journals (Sweden)

    Nuryake Fajaryati

    2016-09-01

    Full Text Available This study aims to develop an e-module as a medium of learning for the practice course of Measuring Instruments and Measurement in the Department of Electronics Engineering Education of Yogyakarta State University and to determine the feasibility of the e-module. This study employed a method of research and development. The development process was conducted through four phases by using the model of Lee and Owens which consisted of analysis phase, design phase, developing and implementation phase, as well as evaluation phase.The evaluation was conducted in several stages. Firstly, an alpha test for product validation was conducted by the experts on material and media. After that, a beta test was conducted by testing the product in small group users. The subjects of this study were the students of Electronics Engineering. The instruments used to collect the data were a validation sheet and questionnaires. The results of qualitative data were then modified into quantitative data with a range of 1 to 5, then they were converted with a rating scale to determine the feasibility of the medium. The results showed that based on the alpha test, the medium was in a very high quality. Meanwhile, in the beta test of the instructional aspect, in terms of material and evaluation and the multimedia aspect the e-module was respectively considered feasible and quite feasible. The four indicators namely text, image, animation and video were all generally considered feasible. In terms of usage aspect, the e-module was considered feasible where its two indicators, namely instructions and navigation, were generally regarded as very feasible by all respondents.

  16. Telomeres, workload and life-history in great tits

    NARCIS (Netherlands)

    Atema, Els

    2017-01-01

    Ageing and the effects of increased workload in great tits A new measurement to quantify variation in quality and rate of ageing between individuals is telomere length. Telomeres are a piece of DNA at the end of chromosomes, and they protect the other DNA. In many species shortening of telomere

  17. Physiological workload reactions to increasing levels of task difficulty

    NARCIS (Netherlands)

    Veltman, J.A.; Gaillard, A.W.K.

    1998-01-01

    The sensitivity of physiological measures to mental workload has been investigated in a flight simulator. Twelve pilots had to fly through a tunnel with different levels of difficulty. Additionally, they had to perform a memory task with four levels of difficulty. The easiest memory task was

  18. Assessment of mental workload and academic motivation in medical students.

    Science.gov (United States)

    Atalay, Kumru Didem; Can, Gulin Feryal; Erdem, Saban Remzi; Muderrisoglu, Ibrahim Haldun

    2016-05-01

    To investigate the level of correlation and direction of linearity between academic motivation and subjective workload. The study was conducted at Baskent University School of Medicine, Ankara, Turkey, from December 2013 to February 2014, and comprised Phase 5 Phase 6 medical students. Subjective workload level was determined by using National Aeronautics and Space Administration Task Load Index scale that was adapted to Turkish. Academic motivation values were obtained with the help of Academic Motivation Scale university form. SPSS 17 was used for statistical analysis. Of the total 105 subjects, 65(62%) students were in Phase 5 and 40(38%) were in Phase 6. Of the Phase 5 students, 18(27.7%) were boys and 47(72.3%) were girls, while of the Phase 6 students, 16(40%) were boys and 24(60%) were girls. There were significant differences in Phase 5 and Phase 6 students for mental effort (p=0.00) and physical effort (p=0.00). The highest correlation in Phase 5 was between mental effort and intrinsic motivation (r=0.343). For Phase 6, highest correlation was between effort and amotivation (r= -0.375). Subjective workload affected academic motivation in medical students.

  19. OEO SRB Weekly Workload Status Report

    Data.gov (United States)

    Social Security Administration — Weekly reports of workloads processed in the Security Records Branch in Boyers, PA. Reports on quantities of work received, processed, pending and average processing...

  20. Subjective sleepiness and sleep quality in adolescents are related to objective and subjective measures of school performance

    Directory of Open Access Journals (Sweden)

    Annemarie eBoschloo

    2013-02-01

    Full Text Available This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11-18 years. Three subjective measures of sleep were used: sleepiness, sleep quality and sleep duration. They were compared to three measures of school performance: objective school grades, self-reported school performance, and parent-reported school performance. Sleepiness – ‘I feel sleepy during the first hours at school’ – appeared to predict both school grades and self-reported school performance. Sleep quality on the other hand – as a measure of (uninterrupted sleep and/or problems falling asleep or waking up – predicted parent-reported school performance. Self- and parent-reported school performance correlated only moderately with school grades. So it turns out that the measures used to measure either sleep or school performance impacts whether or not a relation is found. Further research on sleep and school performance should take this into account. The findings do underscore the notion that sleep in adolescence can be important for learning. They are compatible with the hypothesis that a reduced sleep quality can give rise to sleepiness in the first hours at school which results in lower school performance. This notion could have applied value in counseling adolescents and their parents in changing adolescents’ sleep behavior.

  1. Subjective Sleepiness and Sleep Quality in Adolescents are Related to Objective and Subjective Measures of School Performance.

    Science.gov (United States)

    Boschloo, Annemarie; Krabbendam, Lydia; Dekker, Sanne; Lee, Nikki; de Groot, Renate; Jolles, Jelle

    2013-01-01

    This study investigated the relation between sleep and school performance in a large sample of 561 adolescents aged 11-18 years. Three subjective measures of sleep were used: sleepiness, sleep quality, and sleep duration. They were compared to three measures of school performance: objective school grades, self-reported school performance, and parent-reported school performance. Sleepiness - "I feel sleepy during the first hours at school" - appeared to predict both school grades and self-reported school performance. Sleep quality on the other hand - as a measure of (un)interrupted sleep and/or problems falling asleep or waking up - predicted parent-reported school performance. Self- and parent-reported school performance correlated only moderately with school grades. So it turns out that the measures used to measure either sleep or school performance impacts whether or not a relation is found. Further research on sleep and school performance should take this into account. The findings do underscore the notion that sleep in adolescence can be important for learning. They are compatible with the hypothesis that a reduced sleep quality can give rise to sleepiness in the first hours at school which results in lower school performance. This notion could have applied value in counseling adolescents and their parents in changing adolescents' sleep behavior.

  2. Measuring organizational performance in the hospital industry: an exploratory comparison of objective and subjective methods.

    Science.gov (United States)

    McCracken, M J; McIlwain, T F; Fottler, M D

    2001-11-01

    One of the major challenges facing health services management researchers is the measurement of various aspects of organizational performance. This challenge is exacerbated by a reluctance of many healthcare organizations to share data with researchers because of a fear of competitor access to these data. Even where objective, reliable and valid measures of organizational performance are available, typically they are available only in aggregate form, rather than for individual organizations. In response to these constraints, researchers have used subjective measures of performance often based on the perception of key executives. This research compares the subjective perceptions of hospital executives to the objective financial performance data of 60 hospitals. While the correlations between the subjective and objective measures vary, return of assets (ROA) and operating margin are the most valid subjective financial measures of hospital performance. Implications for future research are discussed.

  3. Do Overweight and Obese Individuals Select a “Moderate Intensity” Workload When Asked to Do So?

    Directory of Open Access Journals (Sweden)

    Cameron W. Hall

    2012-01-01

    Full Text Available The purpose of this study was (1 to determine if overweight/obese individuals (age 26–50 y would self-select moderate exercise intensity when asked to do so and (2 to determine how this self-selected workload compared to exercising at a workload (60% peak aerobic capacity that is known to provide cardioprotective health benefits. Oxygen consumption (VO2 and energy expenditure were measured in 33 men/women (BMI≥27 kg/m2 who completed two 30 min walking bouts: (1 self-selected walking pace on an indoor track and (2 prescribed exercise pace (60% VO2 peak on a treadmill. The data revealed that (1 the prescribed intensity was 6% higher than the self-selected pace and elicited a higher energy expenditure (<0.05 than the self-selected pace (+83 kJ; (2 overweight subjects walked at a slightly lower percentage of VO2 peak than the obese subjects (<0.05; (3 men walked at a lower percentage of VO2 peak than the women (<0.05. In conclusion when asked to walk at a moderate intensity, overweight/obese individuals tended to select a lower workload in the “moderate intensity” range which could be maintained for 30 min; however, a higher intensity which would be more cardioprotective could not be maintained for 30 min by most individuals.

  4. EEG BASED COGNITIVE WORKLOAD CLASSIFICATION DURING NASA MATB-II MULTITASKING

    Directory of Open Access Journals (Sweden)

    Sushil Chandra

    2015-06-01

    Full Text Available The objective of this experiment was to determine the best possible input EEG feature for classification of the workload while designing load balancing logic for an automated operator. The input features compared in this study consisted of spectral features of Electroencephalography, objective scoring and subjective scoring. Method utilizes to identify best EEG feature as an input in Neural Network Classifiers for workload classification, to identify channels which could provide classification with the highest accuracy and for identification of EEG feature which could give discrimination among workload level without adding any classifiers. The result had shown Engagement Index is the best feature for neural network classification.

  5. Mental workload and its relation with fatigue among urban bus drivers

    Directory of Open Access Journals (Sweden)

    Narmin Hassanzadeh-Rangi

    2017-06-01

    Full Text Available Introduction: Driving crash is one of major concerns in all countries. Mental workload reflects the level of attention resources required to meet both objec­tive and subjective performance criteria, which may be affected by task demand, external support, and past experience. Mental workload has been commonly cited as a major cause of workplace and transportation accidents. The objective of this study was assessment of mental workload and its relation with fatigue among urban bus drivers in Tehran, Iran. Methods: In this descriptive and analytical study, the NASA-TLX workload scale and the Samn-Perelli fatigue scale were completed by 194 professional bus drivers. Descriptive statistics as well as correlation and regression analysis were performed for data processing. Results: The total mental workload had highest correlation with the physical demand(r=0.73, p<0.001, the mental demand (r=0.68, p<0.001 and the time pressure (r=0.58, p<0.001. The total fatigue perceived by bus driver had highest correlation with the frustration level (r=0.42, p<0.001, the time pressure (r=0.24, p<0.001 and the mental workload (r=0.21, p<0.001. Conclusion: Mental workload, physical workload and time pressure are important determinants of the total mental workload and fatigue perceived by urban bus drivers. A comprehensive intervention program, include work turnover, trip and work-rest scheduling as well as smoking cessation, was recommended to improve mental workload and fatigue. 

  6. Schrodinger's Cat: Empirical Research into the Radical Subjective solution of the Measurement problem.

    NARCIS (Netherlands)

    Bierman, D.; Whitmarsh, S.

    2007-01-01

    Schrodinger's Cat: Empirical research into the radical subjective solution of the measurement problem Dick J. Bierman & Stephen Whitmarsh The most controversial of all solutions of the measurement problem holds that a measurement is not completed until a conscious observation is made. In other

  7. THE SYSTEM OF STATISTICAL OBJECTIVE AND SUBJECTIVE INDICATORS OF MEASURING QUALITY OF LIFE

    OpenAIRE

    I. Romaniuk

    2015-01-01

    This article examines approaches to defining and measuring quality of life. Each approach to measuring the quality of life contains information that is not contained in the other measures. It describes the economic, subjective and social indicators. The strengths and weaknesses of those indicators are also analyzed.

  8. Differences between Subjective Balanced Occlusion and Measurements Reported With T-Scan III

    Directory of Open Access Journals (Sweden)

    Zana Lila-Krasniqi

    2017-08-01

    CONCLUSION: In our study, it was concluded that there were statistically significant differences of balanced occlusion in all three groups. Also it was concluded that subjective data are not exact with measurements reported with electronic device T-scan III.

  9. Grouping machines for effective workload control

    NARCIS (Netherlands)

    Henrich, P.; Land, M.J.; Gaalman, G.J.C.

    2006-01-01

    Workload control (WLC) allows the release of new orders to the shop floor as long as workload norms for capacity groups, generally a number of functionally similar machines, are not exceeded. Effective WLC requires a profound decision on the grouping of machines as well as on the norm levels for the

  10. Workload dynamics on clusters and grids

    NARCIS (Netherlands)

    Li, H.

    2009-01-01

    This paper presents a comprehensive statistical analysis of a variety of workloads collected on production clusters and Grids. The applications are mostly computational-intensive and each task requires single CPU for processing data, which dominate the workloads on current production Grid systems.

  11. Robust Models for Operator Workload Estimation

    Science.gov (United States)

    2015-03-01

    into distinct cognitive channels (visual, auditory, spatial, etc.) based on our ability to multitask effectively as long as no one channel is...between workload levels. For example, recalling two numbers from working memory may be associated with “low” workload, four numbers with “medium...

  12. A passive brain-computer interface application for the mental workload assessment on professional air traffic controllers during realistic air traffic control tasks.

    Science.gov (United States)

    Aricò, P; Borghini, G; Di Flumeri, G; Colosimo, A; Pozzi, S; Babiloni, F

    2016-01-01

    In the last decades, it has been a fast-growing concept in the neuroscience field. The passive brain-computer interface (p-BCI) systems allow to improve the human-machine interaction (HMI) in operational environments, by using the covert brain activity (eg, mental workload) of the operator. However, p-BCI technology could suffer from some practical issues when used outside the laboratories. In particular, one of the most important limitations is the necessity to recalibrate the p-BCI system each time before its use, to avoid a significant reduction of its reliability in the detection of the considered mental states. The objective of the proposed study was to provide an example of p-BCIs used to evaluate the users' mental workload in a real operational environment. For this purpose, through the facilities provided by the École Nationale de l'Aviation Civile of Toulouse (France), the cerebral activity of 12 professional air traffic control officers (ATCOs) has been recorded while performing high realistic air traffic management scenarios. By the analysis of the ATCOs' brain activity (electroencephalographic signal-EEG) and the subjective workload perception (instantaneous self-assessment) provided by both the examined ATCOs and external air traffic control experts, it has been possible to estimate and evaluate the variation of the mental workload under which the controllers were operating. The results showed (i) a high significant correlation between the neurophysiological and the subjective workload assessment, and (ii) a high reliability over time (up to a month) of the proposed algorithm that was also able to maintain high discrimination accuracies by using a low number of EEG electrodes (~3 EEG channels). In conclusion, the proposed methodology demonstrated the suitability of p-BCI systems in operational environments and the advantages of the neurophysiological measures with respect to the subjective ones. © 2016 Elsevier B.V. All rights reserved.

  13. Workload modelling for data-intensive systems

    CERN Document Server

    Lassnig, Mario

    This thesis presents a comprehensive study built upon the requirements of a global data-intensive system, built for the ATLAS Experiment at CERN's Large Hadron Collider. First, a scalable method is described to capture distributed data management operations in a non-intrusive way. These operations are collected into a globally synchronised sequence of events, the workload. A comparative analysis of this new data-intensive workload against existing computational workloads is conducted, leading to the discovery of the importance of descriptive attributes in the operations. Existing computational workload models only consider the arrival rates of operations, however, in data-intensive systems the correlations between attributes play a central role. Furthermore, the detrimental effect of rapid correlated arrivals, so called bursts, is assessed. A model is proposed that can learn burst behaviour from captured workload, and in turn forecast potential future bursts. To help with the creation of a full representative...

  14. Training and testing ERP-BCIs under different mental workload conditions

    Science.gov (United States)

    Ke, Yufeng; Wang, Peiyuan; Chen, Yuqian; Gu, Bin; Qi, Hongzhi; Zhou, Peng; Ming, Dong

    2016-02-01

    Objective. As one of the most popular and extensively studied paradigms of brain-computer interfaces (BCIs), event-related potential-based BCIs (ERP-BCIs) are usually built and tested in ideal laboratory settings in most existing studies, with subjects concentrating on stimuli and intentionally avoiding possible distractors. This study is aimed at examining the effect of simultaneous mental activities on ERP-BCIs by manipulating various levels of mental workload during the training and/or testing of an ERP-BCI. Approach. Mental workload was manipulated during the training or testing of a row-column P300-speller to investigate how and to what extent the spelling performance and the ERPs evoked by the oddball stimuli are affected by simultaneous mental workload. Main results. Responses of certain ERP components, temporal-occipital N200 and the late reorienting negativity evoked by the oddball stimuli and the classifiability of ERP features between targets and non-targets decreased with the increase of mental workload encountered by the subject. However, the effect of mental workload on the performance of ERP-BCI was not always negative but depended on the conditions where the ERP-BCI was built and applied. The performance of ERP-BCI built under an ideal lab setting without any irrelevant mental activities declined with the increasing mental workload of the testing data. However, the performance was significantly improved when an ERP-BCI was built under an appropriate mental workload level, compared to that built under speller-only conditions. Significance. The adverse effect of concurrent mental activities may present a challenge for ERP-BCIs trained in ideal lab settings but which are to be used in daily work, especially when users are performing demanding mental processing. On the other hand, the positive effects of the mental workload of the training data suggest that introducing appropriate mental workload during training ERP-BCIs is of potential benefit to the

  15. Measuring driver impairments: sleepiness, distraction, and workload.

    Science.gov (United States)

    Ahlstrom, Christer; Kircher, Katja; Fors, Carina; Dukic, Tania; Patten, Christopher; Anund, Anna

    2012-03-01

    Snow was falling heavily when Sarah was driving on a slippery road to her cousin's country cottage. It was dark outside, and the visibility was poor. She had planned to arrive before sunset, but the rental service had made a mistake, and it took hours before she got her rental car at the airport. It was past midnight now, and after a long day of traveling, Sarah was starting to get sleepy. Fortunately, there were only 15 km to go, but her eyelids were starting to feel heavy. To stay awake, she put her favorite CD on, turned up the volume, and started to sing along. This seemed to help a little-good-only 10 km to go. This was when Sarah's phone started ringing, and she awkwardly tried to find the mute button for the car stereo while answering the phone. As she looked up again, she barely caught a glimpse of the red brake lights of the car in front of her as she smashed into it.

  16. Differences in quantitative methods for measuring subjective cognitive decline - results from a prospective memory clinic study

    DEFF Research Database (Denmark)

    Vogel, Asmus; Salem, Lise Cronberg; Andersen, Birgitte Bo

    2016-01-01

    decline. Depression scores were significantly correlated to both scales measuring subjective decline. Linear regression models showed that age did not have a significant contribution to the variance in subjective memory beyond that of depressive symptoms. CONCLUSIONS: Measures for subjective cognitive......BACKGROUND: Cognitive complaints occur frequently in elderly people and may be a risk factor for dementia and cognitive decline. Results from studies on subjective cognitive decline are difficult to compare due to variability in assessment methods, and little is known about how different methods...... influence reports of cognitive decline. METHODS: The Subjective Memory Complaints Scale (SMC) and The Memory Complaint Questionnaire (MAC-Q) were applied in 121 mixed memory clinic patients with mild cognitive symptoms (mean MMSE = 26.8, SD 2.7). The scales were applied independently and raters were blinded...

  17. Mental workload under time pressure can trigger frequent hot flashes in menopausal women.

    Science.gov (United States)

    Park, Mi Kyong; Satoh, Noriaki; Kumashiro, Masaharu

    2008-07-01

    The aim of this study is to examine the relationship between mental workload and occurrence of hot flashes. Twelve women with moderate to severe menopausal hot flashes participated in the study. Subjects participated in both a mental arithmetic task (Task) and control (Non-task) experiments. We measured heart rate, heart rate variability, blood pressure, near infrared spectroscopy, skin temperature, and skin potential level. The incidence of hot flashes was greater in Task than in Non-task. No significant differences between before, during and after hot flashes emerged for the percentage of correct responses and reaction time. However, the percentage of correct responses for two subjects among the ten who experienced hot flashes in Task substantially declined during hot flashes. Chest skin temperatures increased in both Task and Non-task during hot flashes, and regional oxygen saturation was significantly higher in Non-task than in Task. The present study suggested that mental workload under time pressure might be a risk factor for menopausal hot flashes, and the performance of most people who experienced hot flashes was not affected by hot flashes, however, work-related difficulties due to cognitive disturbance during hot flashes might arise in some people.

  18. Biochemical and cardiovascular measures in subjects with noise-induced hearing loss

    Energy Technology Data Exchange (ETDEWEB)

    Gold, S.; Haran, I.; Attias, J.; Shapira, I.; Shahar, A. (Institute for Noise Hazards Research, Ramat Gan (Israel))

    1989-11-01

    Reports on a potential relationship between noise-induced hearing loss (NIHL) and cardiovascular as well as biochemical measures are controversial. This study compares the means of certain cardiovascular and biochemical measures in subjects with NIHL with those in subjects exposed to similar occupational noise, but demonstrating normal hearing. This might indicate certain predisposing factors for NIHL. Eight hundred noise-exposed subjects were divided into two age-matched hearing groups (NIHL and normal hearing). The results showed that the mean values of all the variables examined in both hearing groups were within the normal range. No significant differences were found between the two groups in terms of the distribution of subjects for the indices measured.

  19. Correlation of subjective slipperiness judgements with quantitative COF (Coefficient Of Friction) measurements for structural steel

    Science.gov (United States)

    Purswell, Jerry L.; Schlegel, Robert E.

    1988-06-01

    When there is no simple or accurate procedure for measuring the coefficient of friction (COF) at a job site, workers and/or supervisors involved must make subjective judgments about the slipperiness of the walking and climbing surfaces and in turn decide whether the surface presents a safe or an unsafe condition for work. This project was designed to determine whether these subjective judgment calls did in fact agree with the COF measurements obtained using a mechanical device. It was noted that the coatings chosen for study were subject to a polishing factor by the boot soles during the trials, causing the COF values to become lower as the trials continued. Poor correlation was obtained between subjective ratings of slipperiness and the COF values measured before the trials began. A relatively high correlation was obtained between subjective ratings and the COF values measured after the trials had been completed. A difference was noted in the subjective ratings for the effects of water on a coating for column climbing, but not for walking a beam, suggesting the effects of water on a coating are related to the type of task being performed in steel erection. An increase in the measured COF was noted for all of the coatings when they were wet as compared to the dry condition. The importance of clean shoe soles was clearly demonstrated.

  20. Subjective well-being in schizophrenia as measured with the Subjective Well-Being under Neuroleptic Treatment scale : a review

    NARCIS (Netherlands)

    Vothknecht, Sylke; Schoevers, Robert A.; de Haan, Lieuwe

    Objective: The Subjective Well-being under Neuroleptic Treatment scale (SWN) is the most widely used self-rating scale in recent research of subjective well-being in schizophrenia. We reviewed all available publications on relevant research of subjective well-being using the SWN, in order to

  1. Subjective well-being in schizophrenia as measured with the Subjective Well-Being under Neuroleptic Treatment scale: a review

    NARCIS (Netherlands)

    Vothknecht, Sylke; Schoevers, Robert A.; de Haan, Lieuwe

    2011-01-01

    Objective: The Subjective Well-being under Neuroleptic Treatment scale (SWN) is the most widely used self-rating scale in recent research of subjective well-being in schizophrenia. We reviewed all available publications on relevant research of subjective well-being using the SWN, in order to

  2. Lack of relationship between occupational workload and microscopic alterations in lumbar intervertebral disc disease.

    Science.gov (United States)

    Huschak, Gerald; Holzhausen, Hans-Jürgen; Beier, Andre; Meisel, Hans Jörg; Hoell, Thomas

    2014-01-01

    The study investigated the impact of occupational workloads on disc surgery specimens. We report the relationship between workload and histological features. Specimens were collected prospectively from patients suffering from lumbar disc prolapse (n=90) or spinal osteochondrosis (n=19). Histomorphology and occupational workload data and histomorphological features were evaluated. Occupational data were collected in a structured, standardized patient interview assessing lifting and carrying loads. In this way the exposure was assessed for each test subject's entire working life up to surgery. There was no association between cumulative workload and histological patterns. In a subgroup of patients with a workload period of 12 months prior to surgery a relevant formation of chondrocyte clusters (p=0.055) was apparent. Chondrocyte cluster formation was found in 83% (n=74) of the prolapse patients and in 58% (n=11) of the osteochondrosis patients (p=0.02). Fibrocyte mediated scar formation was found in 55% of the prolapse patients and in 45% of the spinal stenosis patients. Chondrocyte clusters and their de novo collagen matrix did not integrate biomechanically sufficient with collagen fibers of the disc. Disintegration of clusters from disc matrix and formation of intra-discal sequesters were observed. Matrix degeneration was common but displayed no relationship to occupational workload or other histological features. Scar formation was observed in every second specimen. Regenerative chondrocyte cluster proliferation was a common feature in disc specimens and tended to be associated in patients with a workload one year before surgery.

  3. Satisfaction with travel and subjective well-being: development and test of a measurement tool

    NARCIS (Netherlands)

    Ettema, D.F.; Gärling, T.; Eriksson, L.; Friman, M.; Olsson, L.E.; Fujii, S.

    2011-01-01

    Subjective well-being (SWB) that includes individuals’ cognitive and affective evaluations of life in general is proposed to be a more appropriate measure capturing the benefits individuals derive from travel improvements. We develop and testa measure of travel-related SWB, the nine item self-report

  4. Effects of Workloads and Cadences on Frontal Plane Knee Biomechanics in Cycling.

    Science.gov (United States)

    Fang, Ying; Fitzhugh, Eugene C; Crouter, Scott E; Gardner, Jacob K; Zhang, Songning

    2016-02-01

    Although effects of workload and cadence on sagittal plane knee biomechanics in cycling have been widely studied, few studies have examined their impact on the frontal plane. The purpose of this study was to investigate the effects of different workloads and cadences on knee sagittal and frontal plane biomechanics. Eighteen healthy participants (age, 55.7 ± 11.0 yr) volunteered for this study. A motion analysis system and a custom instrumented pedal were used to collect five cycles of three-dimensional kinematics (240 Hz) and pedal reaction force (PRF, 1200 Hz) during 2 min of cycling in each of eight testing conditions, including five workload conditions of 0.5, 1, 1.5, 2, and 2.5 kg at 60 rpm, and three cadence conditions of 70, 80, and 90 rpm with 1-kg workload. Two one-way repeated measures analyses of variance were used to examine the influence of cadence and workload on selected variables (P < 0.05). Increased workloads with constant rpm caused an increased peak knee abduction moment from 5.82 to 14.36 N · m and peak knee extension moment from 11.61 to 37.16 N · m. Increased workloads also significantly increased peak medial and vertical PRF. Increased cadences at the constant workload had no effects on peak knee abduction moment but caused increased peak anterior and vertical PRF and peak knee flexion moment. The findings of this study indicate that increasing workload at constant cadence significantly increased peak knee abduction moment. Further study may be needed to demonstrate the efficacy of appropriate levels of workload and cadence in knee osteoarthritis and other populations with knee problems.

  5. Patient Safety Incidents and Nursing Workload

    Directory of Open Access Journals (Sweden)

    Katya Cuadros Carlesi

    Full Text Available ABSTRACT Objective: to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. Method: quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs was performed using the Therapeutic Interventions Scoring System (TISS-28 and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. Results: 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919 and rate of falls (r = 0.8770. The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. Conclusions: the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload.

  6. Modeling Parallel System Workloads with Temporal Locality

    Science.gov (United States)

    Minh, Tran Ngoc; Wolters, Lex

    In parallel systems, similar jobs tend to arrive within bursty periods. This fact leads to the existence of the locality phenomenon, a persistent similarity between nearby jobs, in real parallel computer workloads. This important phenomenon deserves to be taken into account and used as a characteristic of any workload model. Regrettably, this property has received little if any attention of researchers and synthetic workloads used for performance evaluation to date often do not have locality. With respect to this research trend, Feitelson has suggested a general repetition approach to model locality in synthetic workloads [6]. Using this approach, Li et al. recently introduced a new method for modeling temporal locality in workload attributes such as run time and memory [14]. However, with the assumption that each job in the synthetic workload requires a single processor, the parallelism has not been taken into account in their study. In this paper, we propose a new model for parallel computer workloads based on their result. In our research, we firstly improve their model to control locality of a run time process better and then model the parallelism. The key idea for modeling the parallelism is to control the cross-correlation between the run time and the number of processors. Experimental results show that not only the cross-correlation is controlled well by our model, but also the marginal distribution can be fitted nicely. Furthermore, the locality feature is also obtained in our model.

  7. Evaluating Faculty Workload: An Application of Process Control Charts with Supplementary Run Rules.

    Science.gov (United States)

    Lau, R. S. M.

    1996-01-01

    Describes a method for evaluating faculty workload (measured by time spent in teaching, research, and service) by using process control charts with supplementary run rules that can identify potential overload or underload. (SK)

  8. Validity and reliability of subjective wellbeing indicators in sociological research: The measurement of life satisfaction

    Directory of Open Access Journals (Sweden)

    Mentus Vladimir

    2017-01-01

    Full Text Available The subject of this paper is the level of accuracy i.e. validity and reliability of subjective well-being indicators in sociological research, in case of life satisfaction. First, the relationship between subjective and objective indicators of well-being is presented. Second, the concept of life satisfaction is defined, and the findings of research related to the validity (convergent, discriminant, and predictive and reliability (test-retest, and internal consistency of life satisfaction measures are presented. Third, these findings were reassessed using data originating from large international surveys, which have not been used for this purpose yet. The results in this paper generally contribute to, in quite a large extent existing agreement within the scientific literature about the satisfactory level of validity and reliability of life satisfaction measures i.e. subjective indicators of well-being.

  9. Workload assessment of surgeons: correlation between NASA TLX and blinks.

    Science.gov (United States)

    Zheng, Bin; Jiang, Xianta; Tien, Geoffrey; Meneghetti, Adam; Panton, O Neely M; Atkins, M Stella

    2012-10-01

    Blinks are known as an indicator of visual attention and mental stress. In this study, surgeons' mental workload was evaluated utilizing a paper assessment instrument (National Aeronautics and Space Administration Task Load Index, NASA TLX) and by examining their eye blinks. Correlation between these two assessments was reported. Surgeons' eye motions were video-recorded using a head-mounted eye-tracker while the surgeons performed a laparoscopic procedure on a virtual reality trainer. Blink frequency and duration were computed using computer vision technology. The level of workload experienced during the procedure was reported by surgeons using the NASA TLX. A total of 42 valid videos were recorded from 23 surgeons. After blinks were computed, videos were divided into two groups based on the blink frequency: infrequent group (≤ 6 blinks/min) and frequent group (more than 6 blinks/min). Surgical performance (measured by task time and trajectories of tool tips) was not significantly different between these two groups, but NASA TLX scores were significantly different. Surgeons who blinked infrequently reported a higher level of frustration (46 vs. 34, P = 0.047) and higher overall level of workload (57 vs. 47, P = 0.045) than those who blinked more frequently. The correlation coefficients (Pearson test) between NASA TLX and the blink frequency and duration were -0.17 and 0.446. Reduction of blink frequency and shorter blink duration matched the increasing level of mental workload reported by surgeons. The value of using eye-tracking technology for assessment of surgeon mental workload was shown.

  10. Mood Influences the Concordance of Subjective and Objective Measures of Sleep Duration in Older Adults

    Directory of Open Access Journals (Sweden)

    Marion Baillet

    2016-07-01

    Full Text Available Objective/Background: Sleep plays a central role in maintaining health and cognition. In most epidemiologic studies, sleep is evaluated by self-report questionnaires but several reports suggest that these evaluations might be less accurate than objective measures such as polysomnography or actigraphy. Determinants of the discrepancy between objective and subjective measures remain to be investigated. The aim of this pilot-study was to examine the role of mood states in determining the discrepancy observed between objective and subjective measures of sleep duration in older adults.Patients/Methods: Objective sleep quantity and quality were recorded by actigraphy in a sample of 45 elderly subjects over at least three consecutive nights. Subjective sleep duration and supplementary data, such as mood status and memory, were evaluated using Ecological Momentary Assessment (EMA.Results: A significant discrepancy was observed between EMA and actigraphic measures of sleep duration (p<0.001. The magnitude of this difference was explained by the patient’s mood status (p=0.020. No association was found between the magnitude of this discrepancy and age, sex, sleep quality or memory performance.Conclusion: The discrepancy classically observed between objective and subjective measures of sleep duration can be explained by mood status at the time of awakening. These results have potential implications for epidemiologic and clinical studies examining sleep as a risk factor for morbidity or mortality.

  11. Mood Influences the Concordance of Subjective and Objective Measures of Sleep Duration in Older Adults.

    Science.gov (United States)

    Baillet, Marion; Cosin, Charlotte; Schweitzer, Pierre; Pérès, Karine; Catheline, Gwenaëlle; Swendsen, Joel; Mayo, Willy

    2016-01-01

    Sleep plays a central role in maintaining health and cognition. In most epidemiologic studies, sleep is evaluated by self-report questionnaires but several reports suggest that these evaluations might be less accurate than objective measures such as polysomnography or actigraphy. Determinants of the discrepancy between objective and subjective measures remain to be investigated. The aim of this pilot-study was to examine the role of mood states in determining the discrepancy observed between objective and subjective measures of sleep duration in older adults. Objective sleep quantity and quality were recorded by actigraphy in a sample of 45 elderly subjects over at least three consecutive nights. Subjective sleep duration and supplementary data, such as mood status and memory, were evaluated using ecological momentary assessment (EMA). A significant discrepancy was observed between EMA and actigraphic measures of sleep duration (p sleep quality or memory performance. The discrepancy classically observed between objective and subjective measures of sleep duration can be explained by mood status at the time of awakening. These results have potential implications for epidemiologic and clinical studies examining sleep as a risk factor for morbidity or mortality.

  12. Subjective measures of hearing aid benefit in the NIDCD/VA Clinical Trial.

    Science.gov (United States)

    Haskell, George B; Noffsinger, Douglas; Larson, Vernon D; Williams, David W; Dobie, Robert A; Rogers, Janette L

    2002-08-01

    Subjective measures of performance were assessed on three different hearing aid circuits as part of a large clinical trial. These measurements included the Profile of Hearing Aid Performance and a subjective ranking of individual preference. A multi-center, double-masked clinical trial of hearing aids was conducted at eight VA Medical Centers. Three hearing aid circuits, a linear peak-clipper, a linear compression limiter and a wide dynamic range compressor, were investigated. The experimental design was a three-period, three-treatment crossover design. Subjects (N = 360) were stratified by site and randomized to one of six sequences for the hearing aid circuits. All fittings were binaural and involved a 3-mo trial with each of the three circuits. All subjective measures were administered for unaided and aided conditions at the end of each trial period. While all of the circuits resulted in improved scores on the aided versus the unaided PHAP, there were few conditions in which one circuit outperformed the others. An exception was the aversiveness of sound subscale where the peak clipper frequently scored worse than either the compression limiter or the wide dynamic range compressor. In the subjective ranking scale the compression limiter received more first place rankings than the other two circuits, especially for one subgroup of patients with moderate flat hearing loss. All circuits were perceived as beneficial by these subjects in most situations. The peak clipper scored worse on aversiveness of sound than did the other two circuits for most subjects, while the compression limiter seemed to have a slight advantage in subjective rankings. Most subjects perceived considerable aided benefit in situations involving background noise and reverberation, situations where hearing aid benefit is often questioned.

  13. Cluster analysis for computer workload evaluation

    CERN Document Server

    Landau, K

    1976-01-01

    An introduction to computer workload analysis is given, showing its range of application in computer centre management, system and application programming. Cluster methods are discussed which can be used in conjunction with workload data and cluster algorithms are adapted to the specific set problem. Several samples of CDC 7600- accounting-data-collected at CERN, the European Organization for Nuclear Research-underwent a cluster analysis to determine job groups. The conclusions from resource usage of typical job groups in relation to computer workload analysis are discussed. (17 refs).

  14. Retinal nerve fiber layer measurements by scanning laser polarimetry with enhanced corneal compensation in healthy subjects.

    Science.gov (United States)

    Rao, Harsha L; Venkatesh, Chirravuri R; Vidyasagar, Kelli; Yadav, Ravi K; Addepalli, Uday K; Jude, Aarthi; Senthil, Sirisha; Garudadri, Chandra S

    2014-12-01

    To evaluate the (i) effects of biological (age and axial length) and instrument-related [typical scan score (TSS) and corneal birefringence] parameters on the retinal nerve fiber layer (RNFL) measurements and (ii) repeatability of RNFL measurements with the enhanced corneal compensation (ECC) protocol of scanning laser polarimetry (SLP) in healthy subjects. In a cross-sectional study, 140 eyes of 73 healthy subjects underwent RNFL imaging with the ECC protocol of SLP. Linear mixed modeling methods were used to evaluate the effects of age, axial length, TSS, and corneal birefringence on RNFL measurements. One randomly selected eye of 48 subjects from the cohort underwent 3 serial scans during the same session to determine the repeatability. Age significantly influenced all RNFL measurements. RNFL measurements decreased by 1 µm for every decade increase in age. TSS affected the overall average RNFL measurement (β=-0.62, P=0.003), whereas residual anterior segment retardance affected the superior quadrant measurement (β=1.14, P=0.01). Axial length and corneal birefringence measurements did not influence RNFL measurements. Repeatability, as assessed by the coefficient of variation, ranged between 1.7% for the overall average RNFL measurement and 11.4% for th nerve fiber indicator. Age significantly affected all RNFL measurements with the ECC protocol of SLP, whereas TSS and residual anterior segment retardance affected the overall average and the superior average RNFL measurements, respectively. Axial length and corneal birefringence measurements did not influence any RNFL measurements. RNFL measurements had good intrasession repeatability. These results are important while evaluating the change in structural measurements over time in glaucoma patients.

  15. Workload composition of the organic horticulture.

    Science.gov (United States)

    Abrahão, R F; Ribeiro, I A V; Tereso, M J A

    2012-01-01

    This project aimed the characterization of the physical workload of the organic horticulture by determining the frequency of exposure of operators to some activity categories. To do this, an adaptation of the PATH method (Posture, Activities, Tools and Handling) was done to be used in the context of agriculture work. The approach included an evaluation of physical effort demanded to perform the tasks in the work systems from an systematic sampling of work situations from a synchronized monitoring of the heart rate; a characterization of posture repertoire adopted by workers by adapting the OWAS method; an identification of pain body areas using the Corlett diagram; and a subjective evaluation of perceived effort using the RPE Borg scale. The results of the individual assessments were cross correlated and explained from an observation of the work activity. Postural demands were more significant than cardiovascular demands for the studied tasks, and correlated positively with the expressions of bodily discomfort. It is expected that, besides the knowledge obtained of the physical effort demanded by organic horticulture, this project will be useful for the development of new technologies directed to minimize the difficulties of the human work and to raise the work productivity.

  16. Impact of simulated three-dimensional perception on precision of depth judgements, technical performance and perceived workload in laparoscopy.

    Science.gov (United States)

    Sakata, S; Grove, P M; Hill, A; Watson, M O; Stevenson, A R L

    2017-07-01

    This study compared precision of depth judgements, technical performance and workload using two-dimensional (2D) and three-dimensional (3D) laparoscopic displays across different viewing distances. It also compared the accuracy of 3D displays with natural viewing, along with the relationship between stereoacuity and 3D laparoscopic performance. A counterbalanced within-subjects design with random assignment to testing sequences was used. The system could display 2D or 3D images with the same set-up. A Howard-Dolman apparatus assessed precision of depth judgements, and three laparoscopic tasks (peg transfer, navigation in space and suturing) assessed performance (time to completion). Participants completed tasks in all combinations of two viewing modes (2D, 3D) and two viewing distances (1 m, 3 m). Other measures administered included the National Aeronautics and Space Administration Task Load Index (perceived workload) and the Randot(®) Stereotest (stereoacuity). Depth judgements were 6·2 times as precise at 1 m and 3·0 times as precise at 3 m using 3D versus 2D displays (P large improvements over 2D displays in precision of depth judgements, technical performance and perceived workload. © 2017 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

  17. Objective and subjective measures of neighborhood environment (NE): relationships with transportation physical activity among older persons.

    Science.gov (United States)

    Nyunt, Ma Shwe Zin; Shuvo, Faysal Kabir; Eng, Jia Yen; Yap, Keng Bee; Scherer, Samuel; Hee, Li Min; Chan, Siew Pang; Ng, Tze Pin

    2015-09-15

    This study examined the associations of subjective and objective measures of the neighbourhood environment with the transportation physical activity of community-dwelling older persons in Singapore. A modified version of the Neighborhood Environment Walkability Scale (NEWS) and Geographical Information System (GIS) measures of the built environment characteristics were related to the frequency of walking for transportation purpose in a study sample of older persons living in high-density apartment blocks within a public housing estate in Singapore. Relevant measured variables to assess the complex relationships among built environment measures and transportation physical activity were examined using structural equation modelling and multiple regression analyses. The subjective measures of residential density, street connectivity, land use mix diversity and aesthetic environment and the objective GIS measure of Accessibility Index have positively significant independent associations with transportation physical activity, after adjusting for demographics, socio-economic and health status. Subjective and objective measures are non-overlapping measures complementing each other in providing information on built environment characteristics. For elderly living in a high-density urban neighborhood, well connected street, diversity of land use mix, close proximity to amenities and facilities, and aesthetic environment were associated with higher frequency of walking for transportation purposes.

  18. [Nursing workloads and working conditions: integrative review].

    Science.gov (United States)

    Schmoeller, Roseli; Trindade, Letícia de Lima; Neis, Márcia Binder; Gelbcke, Francine Lima; de Pires, Denise Elvira Pires

    2011-06-01

    This study reviews theoretical production concerning workloads and working conditions for nurses. For that, an integrative review was carried out using scientific articles, theses and dissertations indexed in two Brazilian databases, Virtual Health Care Library (Biblioteca Virtual de Saúde) and Digital Database of Dissertations (Banco Digital de Teses), over the last ten years. From 132 identified studies, 27 were selected. Results indicate workloads as responsible for professional weariness, affecting the occurrence of work accidents and health problems. In order to adequate workloads studies indicate some strategies, such as having an adequate numbers of employees, continuing education, and better working conditions. The challenge is to continue research that reveal more precisely the relationships between workloads, working conditions, and health of the nursing team.

  19. Reproducibility of the measurements of knee joint proprioception in patients with osteoarthritis of the knee and healthy subject

    NARCIS (Netherlands)

    Hurkmans, E.; van der Esch, M.; Ostelo, R.W.J.G.; Knol, D.L.; Dekker, J; Steultjens, M

    2007-01-01

    Objective. To estimate the inter- and intrarater reliability and agreement of instrumented knee joint proprioception measurement in subjects with knee osteoarthritis (OA) and healthy subjects; to assess the effect of variations in the measurement procedure on agreement parameters. Methods.

  20. Telomeres, workload and life-history in great tits

    OpenAIRE

    Atema, Els

    2017-01-01

    Ageing and the effects of increased workload in great tits A new measurement to quantify variation in quality and rate of ageing between individuals is telomere length. Telomeres are a piece of DNA at the end of chromosomes, and they protect the other DNA. In many species shortening of telomere length with increasing age was demonstrated. This shortening is accelerated by processes that also decrease life expectancy. In this project we discovered that telomeres of great tits differ from telom...

  1. Physiological Indicators of Workload in a Remotely Piloted Aircraft Simulation

    Science.gov (United States)

    2015-10-01

    situations. That is, performance decrements will have to occur before high workload can be recognized. It would not benefit commanders to recognize, for... caffeine and tobacco), by pain and discomfort, and by diurnal variations. It is worth noting that, there are limitations with all physiological measures...multiple semi-autonomous RPA. The benefits of such automated systems include: reducing manpower requirements, lower life-cycle costs, and decreased

  2. Evaluation of drivers\\' behavior performing a curve under mental workload

    OpenAIRE

    Fábio Sartori Vieira

    2016-01-01

    Driving under distraction may lead drivers to wrong actions that can result in serious accidents. The objective of this thesis was to apply a driving simulator to verify variations in drivers\\' behavior while driving. Behavior to drive on a curve was measured by variation in drivers\\' speed profile in a virtualized highway. The comparison was performed between two identical simulations, one involving drivers distracted with a mental workload, and other in which they were full aware of driving...

  3. Measuring Welfare beyond GDP : 'Objective' and 'Subjective' Indicators in Sweden, 1968-2015

    Directory of Open Access Journals (Sweden)

    Christopher Kullenberg

    2017-10-01

    Full Text Available This article analyses a series of negotiations on how to measure welfare and quality of life in Sweden beyond economic indicators. It departs from a 2015 Government Official Report that advanced a strong recommendation to measure only 'objective indicators' of quality of life, rather than relying on what is referred to as 'subjective indicators' such as life satisfaction and happiness. The assertion of strictly 'objective' indicators falls back on a sociological perspective developed in the 1970s, which conceived of welfare as being measurable as 'levels of living', a framework that came to be called 'the Scandinavian model of welfare research'. However, in the mid-2000s, objective indicators were challenged scientifically by the emerging field of happiness studies, which also found political advocates in Sweden who argued that subjective indicators should become an integral part of measuring welfare. This tension between 'subjective' and 'objective' measurements resulted in a controversy between several actors about what should count as a valuable measurement of welfare. As a consequence, we argue that the creation of such value meters is closely intertwined with how welfare is defined, and by what measures welfare should be carried through.

  4. Workflow interruptions and mental workload in hospital pediatricians: an observational study.

    Science.gov (United States)

    Weigl, Matthias; Müller, Andreas; Angerer, Peter; Hoffmann, Florian

    2014-09-24

    Pediatricians' workload is increasingly thought to affect pediatricians' quality of work life and patient safety. Workflow interruptions are a frequent stressor in clinical work, impeding clinicians' attention and contributing to clinical malpractice. We aimed to investigate prospective associations of workflow interruptions with multiple dimensions of mental workload in pediatricians during clinical day shifts. In an Academic Children's Hospital a prospective study of 28 full shift observations was conducted among pediatricians providing ward coverage. The prevalence of workflow interruptions was based on expert observation using a validated observation instrument. Concurrently, Pediatricians' workload ratings were assessed with three workload dimensions of the well-validated NASA-Task Load Index: mental demands, effort, and frustration. Observed pediatricians were, on average, disrupted 4.7 times per hour. Most frequent were interruptions by colleagues (30.2%), nursing staff (29.7%), and by telephone/beeper calls (16.3%). Interruption measures were correlated with two workload outcomes of interest: frequent workflow interruptions were related to less cognitive demands, but frequent interruptions were associated with increased frustration. With regard to single sources, interruptions by colleagues showed the strongest associations to workload. The findings provide insights into specific pathways between different types of interruptions and pediatricians' mental workload. These findings suggest further research and yield a number of work and organization re-design suggestions for pediatric care.

  5. Mood and objective and subjective measures of sleep during late pregnancy and the postpartum period.

    Science.gov (United States)

    Coo, Soledad; Milgrom, Jeannette; Trinder, John

    2014-01-01

    This study examined the association between measures of objective sleep (OS) and subjective sleep (SS) to postpartum mood in healthy women from the third trimester of pregnancy to 10 to 12 weeks postpartum. Twenty-nine pregnant women completed self-report measures of mood and SS, and wore actigraphs for 7 continuous days during the third trimester (Time 1), within 15 days (Time 2), and 10 to 12 weeks postpartum (Time 3). The subjective perception of marked daytime dysfunction was associated with low mood during Time 1 and Time 3. Poor nighttime SS was related to low mood only at Time 2, whereas poor nighttime OS influenced stress during the same assessment time. These data indicate a stronger association between postpartum mood and the subjective perception of sleep than with OS quality and duration in healthy, non-depressed women, and highlight the awareness of poor daytime functioning as a significant contributor to new mothers' emotional wellbeing.

  6. Objectively and subjectively measured physical activity: associations with cognition and academic achievement in adolescents

    NARCIS (Netherlands)

    Van Dijk, Martin; De Groot, Renate; Van Acker, Frederik; Savelberg, Hans; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Van Acker, F., Savelberg, H. C. M., & Kirschner, P. A. (2013, 26 February). Objectively and subjectively measured physical activity: associations with cognition and academic achievement in adolescents. Presentation at the CELSTEC plenary, Heerlen, The

  7. Comparison of the subjective sense of high or low metabolism and objectively measured resting metabolic rate.

    Science.gov (United States)

    Wallhuss, Andreas; Isik, Markus; Nystrom, Fredrik H

    2010-09-01

    To measure caloric intake, physical activity level and resting metabolic rate in participants having the subjective opinion of either having a high or low metabolic rate. Recruitment by local advertising of healthy subjects feeling that they have high or low metabolism, i.e. either a tendency to easily stay lean ('high') or to very easily gain weight ('low') also when taking food intake in comparison with physical activity into account. Walking distance was estimated by pedometry, assessment of caloric intake was determined by food registration. Measurement of resting metabolic rate was performed in the fasting state. We recruited 44 participants with a sense of 'high' metabolism and 12 subjects in the contrasting group. Subjects with 'high' metabolism were leaner ('high': 20.4 +/- 2.1 kg/m(2), 'low': 27.8 +/- 7.5 kg/m(2), p difference in the measured resting metabolic rate between the two groups ('high': 7230 +/- 1233 kJ/24 h, 'low': 7430 +/- 1422 kJ/24 h, p = 0.6), nor was there any difference in physical activity measured by pedometry. Resting metabolic rate was negatively correlated with age and positively correlated with BMI in multivariate analyses of the total cohort. The sense of having a low or high metabolic rate is not related to actual resting metabolic rate.

  8. "Chips with Everything": A Laboratory Exercise for Comparing Subjective and Objective Measurements of Potato Chips

    Science.gov (United States)

    Davies, Cathy

    2005-01-01

    The following laboratory exercise was designed to aid student understanding of the differences between subjective and objective measurements. Students assess the color and texture of different varieties of potato chip (crisps) by means of an intensity rating scale and a rank test and objectively with a colorimeter and texture analyzer. For data…

  9. Measuring Quality of Life in Stroke Subjects Receiving an Implanted Neural Prosthesis for Drop Foot

    NARCIS (Netherlands)

    Kottink, Anke I.; IJzerman, Maarten Joost; Hermens, Hermanus J.; Groothuis-Oudshoorn, Catharina Gerarda Maria; Kottink, A.I.R.

    2010-01-01

    The aim was to determine if the treatment of a drop foot by means of an implantable two-channel peroneal nerve stimulator improves health-related quality of life (HRQoL). All subjects were measured at baseline and after a follow-up period of 12 and 26 weeks. Twenty-nine stroke survivors with chronic

  10. Objectively versus subjectively measured physical activity: associations with cognition and academic achievement in adolescents

    NARCIS (Netherlands)

    Van Dijk, Martin; De Groot, Renate; Savelberg, Hans; Van Acker, Frederik; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Savelberg, H. C. M., Van Acker, F. H. M., & Kirschner, P. A. (2013, 25 May). Objectively versus subjectively measured physical activity: associations with cognition and academic achievement in adolescents. Poster presentation at the ISBNPA conference 2013, Ghent,

  11. A Short Introduction to Subjective Well-being: Measurement, Correlates and Policy Uses

    NARCIS (Netherlands)

    Hoorn, A.A.J. van

    2008-01-01

    Since the emergence of the field over five decades ago, the subjective well-being (SWB; e.g. self-reported happiness or life satisfaction) literature has progressed rapidly. This overview discusses the state of the art in the measurement of SWB, the understanding of the factors determining SWB,

  12. FY17 CSSE L2 Milestone Report: Analyzing Power Usage Characteristics of Workloads Running on Trinity.

    Energy Technology Data Exchange (ETDEWEB)

    Pedretti, Kevin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    This report summarizes the work performed as part of a FY17 CSSE L2 milestone to in- vestigate the power usage behavior of ASC workloads running on the ATS-1 Trinity plat- form. Techniques were developed to instrument application code regions of interest using the Power API together with the Kokkos profiling interface and Caliper annotation library. Experiments were performed to understand the power usage behavior of mini-applications and the SNL/ATDM SPARC application running on ATS-1 Trinity Haswell and Knights Landing compute nodes. A taxonomy of power measurement approaches was identified and presented, providing a guide for application developers to follow. Controlled scaling study experiments were performed on up to 2048 nodes of Trinity along with smaller scale ex- periments on Trinity testbed systems. Additionally, power and energy system monitoring information from Trinity was collected and archived for post analysis of "in-the-wild" work- loads. Results were analyzed to assess the sensitivity of the workloads to ATS-1 compute node type (Haswell vs. Knights Landing), CPU frequency control, node-level power capping control, OpenMP configuration, Knights Landing on-package memory configuration, and algorithm/solver configuration. Overall, this milestone lays groundwork for addressing the long-term goal of determining how to best use and operate future ASC platforms to achieve the greatest benefit subject to a constrained power budget.

  13. Comparison of verbal and pictorial measures of hunger during fasting in normal weight and obese subjects.

    Science.gov (United States)

    Lowe, M R; Friedman, M I; Mattes, R; Kopyt, D; Gayda, C

    2000-11-01

    Friedman, Ulrich, and Mattes described a new pictorial instrument for assessing hunger wherein respondents outline areas on a drawing of a human figure to depict the location of their hunger sensations. The present study compared normal weight and obese individuals on the pictorial measure and on more traditional verbal hunger measures during a 22-hour fast. The pictorial measure, along with 13 verbal items assessing hunger and hunger-related symptoms, was administered to 29 normal weight college students and 46 overweight clinic patients four times during a 22-hour fast. Factor analyses of verbal hunger items produced Hunger, Somatic Symptoms, and Stomach Symptoms factors. The pictorial measure was divided into peripheral (arms, legs, head) and central (trunk) body areas. The increases in hunger during the fast were greater when measured using the pictorial as opposed to the verbal instrument. Correlations between and within the three verbal hunger measures and two pictorial measures were generally few in number and modest in size. The overall pattern of correlations suggested that the verbally based hunger measures more adequately reflected the experience of hunger in normal weight than in obese individuals. A significant interaction between weight status and assessment period was found for the pictorial measure, indicating that normal weight subjects experienced more bodily hunger than overweight subjects initially but experienced less hunger than obese subjects after a prolonged period of food deprivation. Although more testing is needed, these results suggest that the pictorial hunger assessment provides information about the experience of hunger that could complement information provided by traditional verbally based hunger measures.

  14. Examining complexity across domains: relating subjective and objective measures of affective environmental scenes, paintings and music.

    Science.gov (United States)

    Marin, Manuela M; Leder, Helmut

    2013-01-01

    Subjective complexity has been found to be related to hedonic measures of preference, pleasantness and beauty, but there is no consensus about the nature of this relationship in the visual and musical domains. Moreover, the affective content of stimuli has been largely neglected so far in the study of complexity but is crucial in many everyday contexts and in aesthetic experiences. We thus propose a cross-domain approach that acknowledges the multidimensional nature of complexity and that uses a wide range of objective complexity measures combined with subjective ratings. In four experiments, we employed pictures of affective environmental scenes, representational paintings, and Romantic solo and chamber music excerpts. Stimuli were pre-selected to vary in emotional content (pleasantness and arousal) and complexity (low versus high number of elements). For each set of stimuli, in a between-subjects design, ratings of familiarity, complexity, pleasantness and arousal were obtained for a presentation time of 25 s from 152 participants. In line with Berlyne's collative-motivation model, statistical analyses controlling for familiarity revealed a positive relationship between subjective complexity and arousal, and the highest correlations were observed for musical stimuli. Evidence for a mediating role of arousal in the complexity-pleasantness relationship was demonstrated in all experiments, but was only significant for females with regard to music. The direction and strength of the linear relationship between complexity and pleasantness depended on the stimulus type and gender. For environmental scenes, the root mean square contrast measures and measures of compressed file size correlated best with subjective complexity, whereas only edge detection based on phase congruency yielded equivalent results for representational paintings. Measures of compressed file size and event density also showed positive correlations with complexity and arousal in music, which is

  15. Objective measurement of daytime napping, cognitive dysfunction and subjective sleepiness in Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Samuel J Bolitho

    Full Text Available INTRODUCTION: Sleep-wake disturbances and concomitant cognitive dysfunction in Parkinson's disease (PD contribute significantly to morbidity in patients and their carers. Subjectively reported daytime sleep disturbance is observed in over half of all patients with PD and has been linked to executive cognitive dysfunction. The current study used daytime actigraphy, a novel objective measure of napping and related this to neuropsychological performance in a sample of PD patients and healthy, age and gender-matched controls. Furthermore this study aimed to identify patients with PD who may benefit from pharmacologic and behavioural intervention to improve these symptoms. METHODS: Eighty-five PD patients and 21 healthy, age-matched controls completed 14 days of wrist actigraphy within two weeks of neuropsychological testing. Objective napping measures were derived from actigraphy using a standardised protocol and subjective daytime sleepiness was recorded by the previously validated Epworth Sleepiness Scale. RESULTS: Patients with PD had a 225% increase in the mean nap time per day (minutes as recorded by actigraphy compared to age matched controls (39.2 ± 35.2 vs. 11.5 ± 11.0 minutes respectively, p < 0.001. Significantly, differences in napping duration between patients, as recorded by actigraphy were not distinguished by their ratings on the subjective measurement of excessive daytime sleepiness. Finally, those patients with excessive daytime napping showed greater cognitive deficits in the domains of attention, semantic verbal fluency and processing speed. CONCLUSION: This study confirms increased levels of napping in PD, a finding that is concordant with subjective reports. However, subjective self-report measures of excessive daytime sleepiness do not robustly identify excessive napping in PD. Fronto-subcortical cognitive dysfunction was observed in those patients who napped excessively. Furthermore, this study suggests that daytime

  16. Objective Measurement of Daytime Napping, Cognitive Dysfunction and Subjective Sleepiness in Parkinson’s Disease

    Science.gov (United States)

    Bolitho, Samuel J.; Naismith, Sharon L.; Salahuddin, Pierre; Terpening, Zoe; Grunstein, Ron R.; Lewis, Simon J. G.

    2013-01-01

    Introduction Sleep-wake disturbances and concomitant cognitive dysfunction in Parkinson’s disease (PD) contribute significantly to morbidity in patients and their carers. Subjectively reported daytime sleep disturbance is observed in over half of all patients with PD and has been linked to executive cognitive dysfunction. The current study used daytime actigraphy, a novel objective measure of napping and related this to neuropsychological performance in a sample of PD patients and healthy, age and gender-matched controls. Furthermore this study aimed to identify patients with PD who may benefit from pharmacologic and behavioural intervention to improve these symptoms. Methods Eighty-five PD patients and 21 healthy, age-matched controls completed 14 days of wrist actigraphy within two weeks of neuropsychological testing. Objective napping measures were derived from actigraphy using a standardised protocol and subjective daytime sleepiness was recorded by the previously validated Epworth Sleepiness Scale. Results Patients with PD had a 225% increase in the mean nap time per day (minutes) as recorded by actigraphy compared to age matched controls (39.2 ± 35.2 vs. 11.5 ± 11.0 minutes respectively, p napping duration between patients, as recorded by actigraphy were not distinguished by their ratings on the subjective measurement of excessive daytime sleepiness. Finally, those patients with excessive daytime napping showed greater cognitive deficits in the domains of attention, semantic verbal fluency and processing speed. Conclusion This study confirms increased levels of napping in PD, a finding that is concordant with subjective reports. However, subjective self-report measures of excessive daytime sleepiness do not robustly identify excessive napping in PD. Fronto-subcortical cognitive dysfunction was observed in those patients who napped excessively. Furthermore, this study suggests that daytime actigraphy, a non-invasive and inexpensive objective measure of

  17. Objective measurement of daytime napping, cognitive dysfunction and subjective sleepiness in Parkinson's disease.

    Science.gov (United States)

    Bolitho, Samuel J; Naismith, Sharon L; Salahuddin, Pierre; Terpening, Zoe; Grunstein, Ron R; Lewis, Simon J G

    2013-01-01

    Sleep-wake disturbances and concomitant cognitive dysfunction in Parkinson's disease (PD) contribute significantly to morbidity in patients and their carers. Subjectively reported daytime sleep disturbance is observed in over half of all patients with PD and has been linked to executive cognitive dysfunction. The current study used daytime actigraphy, a novel objective measure of napping and related this to neuropsychological performance in a sample of PD patients and healthy, age and gender-matched controls. Furthermore this study aimed to identify patients with PD who may benefit from pharmacologic and behavioural intervention to improve these symptoms. Eighty-five PD patients and 21 healthy, age-matched controls completed 14 days of wrist actigraphy within two weeks of neuropsychological testing. Objective napping measures were derived from actigraphy using a standardised protocol and subjective daytime sleepiness was recorded by the previously validated Epworth Sleepiness Scale. Patients with PD had a 225% increase in the mean nap time per day (minutes) as recorded by actigraphy compared to age matched controls (39.2 ± 35.2 vs. 11.5 ± 11.0 minutes respectively, p napping duration between patients, as recorded by actigraphy were not distinguished by their ratings on the subjective measurement of excessive daytime sleepiness. Finally, those patients with excessive daytime napping showed greater cognitive deficits in the domains of attention, semantic verbal fluency and processing speed. This study confirms increased levels of napping in PD, a finding that is concordant with subjective reports. However, subjective self-report measures of excessive daytime sleepiness do not robustly identify excessive napping in PD. Fronto-subcortical cognitive dysfunction was observed in those patients who napped excessively. Furthermore, this study suggests that daytime actigraphy, a non-invasive and inexpensive objective measure of daytime sleep, can identify patients with PD

  18. Local effects in the respiratory tract: relevance of subjectively measured irritation for setting occupational exposure limits.

    Science.gov (United States)

    Arts, Josje H E; de Heer, Cees; Woutersen, Ruud A

    2006-04-01

    Chemosensory effects of stimulation by a chemical can either be irritating (trigeminal stimulation) or odorous (olfactory stimulation) or both. For odorous irritants, a clear-cut distinction between odour and irritation is difficult to make. The differences in the lowest concentration found to be irritating to the respiratory tract in humans when compared to experimental animals has brought much debate in the process of setting occupational exposure limits (OELs) for such chemicals. In this paper it will be discussed as to how far subjectively measured sensory irritation threshold levels can be used to establish OELs. Data on respiratory irritation of four odorous irritants were retrieved from public literature and discussed, viz. acetone, formaldehyde, furfural and sulphur dioxide. Objective measures of irritation yielded results that differed from subjective evaluations. Important factors modulating the reported levels of irritation and health symptoms include the perception of odour intensity, exposure history and the individual's bias to report irritation on the basis of his/her prejudice or knowledge of the compound. Subjective measures alone are less appropriate for establishing sensory irritation thresholds of odorous irritants and are, therefore, less suitable to establish OELs without supporting evidence. Objectively measured irritation in humans, the Alarie assay (an experimental animal test assessing the concentration that results in a 50% reduction of the breathing frequency) and repeated exposure studies in animals may be of help to study objective irritation. If subjective measurements are used to study sensory irritation, the study design should at least include: measurement of both incidence and severity determined at several concentrations, an appropriate (0 ppm) control condition, preferably a non-irritant odorant control exposure, validated questionnaires and correct concentration measurements.

  19. Multichannel SQUID system for measurement of spinal cord evoked magnetic field for supine subjects

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Y; Kawai, J; Miyamoto, M; Uehara, G; Ogata, H [Applied Electronics Laboratory, Kanazawa Institute of Technology, 3 Amaike, Kanazawa, Ishikawa, 920-1331 (Japan); Kawabata, S [Section of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 (Japan)

    2008-02-01

    A SQUID biomagnetometer system for cervical spinal cord evoked field (SCEF) was developed to investigate a non-invasive diagnosis of function of the spinal cord. The measurement system was characterized by a uniquely shaped cryostat designed for supine subjects. The cryostat has a vertical cylindrical main body whose dimensions are 500 mm in diameter and 940 mm in height and a horizontal protrusion from the side surface with 390 mm of length. The sensor array of 35 LTS-SQUID vector gradiometers directed vertically upward is installed in the end of the protruded part. Subjects lie on a bed in supine position with the head running off the edge of the bed and the back of the neck supported on the upper surface of the protruded part of the cryostat standing beside the bed. This structure readily enables the sensor array to approach close to the neck of the supine subject. The subjects can keep their posture stable during the measurement. We demonstrated the cervical SCEF was successfully detected from a healthy subject who was given electric stimulation to the median nerve at the wrist. The intensity of the evoked magnetic field was 40-70 fT in amplitude. The neural signal propagating along the spinal cord was magnetically observed from the investigation of the transition of the magnetic field distribution.

  20. Comparison of Occlusion Effect in Normal Hearing Subjects via Real Ear Measurement and Audiometric Bing Test

    Directory of Open Access Journals (Sweden)

    Meymaneh Jafari

    2009-12-01

    Full Text Available Background and Aim: One of the most common complaints, particularly among patients with normal or near normal low-frequency hearing, is that their voice sounds "hollow". This is associated with "Occlusion effect". The aim of this study was to comparison of occlusion effect in normal hearing subjects via Real Ear Measurement and Audiometric Bing test. Materials and Method: Twenty volunteers with normal hearing (10 male, 10 female, with ages ranging from 18 – 24 years were enrolled in this study. First, audiometric Bing test was performed in frequencies of 250, 500, 750 and 1000 Hz. Then in real ear measurement, subjects were instructed to vocalize /â/ and /i/ for 5 seconds. Probe microphone was recorded the sound pressure in the ear canals. The degrees of occlusion effect unit were obtained for further analysis.Results: The means of occlusion effect were present in all subjects. There was no correlation between the results of audiometric Bing test and real-ear measurement. No significant difference was obtained between genders and monaural or binaural occlusion in real-ear measurement. But in audiometric Bing test, the difference between monaural or binaural occlusion was significant(p<0.05.Conclusion: The peak of occlusion effect varies significantly among hearing aid users, so the hearing aid must be tuned. Probe- microphone measures will assist in determination how much gain is enough, and where frequency- specific adjustments are needed.

  1. Anxiety and cerebral blood flow during behavioral challenge. Dissociation of central from peripheral and subjective measures

    Energy Technology Data Exchange (ETDEWEB)

    Zohar, J.; Insel, T.R.; Berman, K.F.; Foa, E.B.; Hill, J.L.; Weinberger, D.R.

    1989-06-01

    To investigate the relationship between anxiety and regional cerebral blood flow, we administered behavioral challenges to 10 patients with obsessive-compulsive disorder while measuring regional cerebral blood flow with the xenon 133 inhalation technique. Each patient was studied under three conditions: relaxation, imaginal flooding, and in vivo (actual) exposure to the phobic stimulus. Subjective anxiety, obsessive-compulsive ratings, and autonomic measures (heart rate, blood pressure) increased significantly, but respiratory rate and PCO/sub 2/ did not change across the three conditions. Regional cerebral blood flow increased slightly (in the temporal region) during imaginal flooding, but decreased markedly in several cortical regions during in vivo exposure, when anxiety was highest by subjective and peripheral autonomic measures. These results demonstrate that intense anxiety can be associated with decreased rather than increased cortical perfusion and that ostensibly related states of anxiety (eg, anticipatory and obsessional anxiety) may be associated with opposite effects on regional cerebral blood flow.

  2. A psychometric evaluation of the Taiwan version of the Individual Workload Perception Scale.

    Science.gov (United States)

    Lin, Shu-Yuan; Lin, Chung-Hui; Yeh, Mei Chang; Lin, Shu-Ying; Hwang, Yueh-Jiau

    2011-02-01

    The aim was to evaluate the psychometric properties of the Taiwan version of the Revised Individual Workload Perception Scale on staff nurses in southern Taiwan. Most psychometric measures of the nursing work environment were developed in North America and reflect nursing practice in Western health care environments. As these instruments are used most often in translation, it is important to inquire whether they appropriately capture the characteristics of nursing work in environments outside of the original contexts. A descriptive, cross-sectional study was conducted between 1 June-30 September 2009, with a convenience sample of 344 nurses providing direct patient care at a regional teaching hospital in southern Taiwan. The Taiwan version of the Revised Individual Workload Perception Scale was created by translating the original English language Individual Workload Perception Scale-Revised, which is used to measure the staff nurses' perceptions of their work environment. The Taiwan version of the Revised Individual Workload Perception Scale is a 24-item five-point Likert scale measuring manager support, peer support, unit support, workload and intent to stay. Content validity, construct validity and reliability of the Taiwan version of the Revised Individual Workload Perception Scale were evaluated. The content validity index of the Taiwan version of the Revised Individual Workload Perception Scale was 0.93. Cronbach's alpha for the total Taiwan version of the Revised Individual Workload Perception Scale was 0.88, with a range of 0.61-0.85 for the subscales. Factorial validity was supported using a five-factor model solution that accounted for 55.47% of the total variance for nursing work environment. Manager support had the highest explained variance (28.38%). Acceptable reliability and content validity were found; the Taiwan version of the Revised Individual Workload Perception Scale is recommended for measuring nurses' perceptions of their work environment

  3. Evaluation of ride quality measurement procedures by subjective experiments using simulators

    Science.gov (United States)

    Klauder, L. T., Jr.; Clevenson, S. A.

    1975-01-01

    Since ride quality is, by definition, a matter of passenger response, there is need for a qualification procedure (QP) for establishing the degree to which any particular ride quality measurement procedure (RQMP) does correlate with passenger responses. Once established, such a QP will provide very useful guidance for optimal adjustment of the various parameters which any given RQMP contains. A QP is proposed based on use of a ride motion simulator and on test subject responses to recordings of actual vehicle motions. Test subject responses are used to determine simulator gain settings for the individual recordings such as to make all of the simulated rides equally uncomfortable to the test subjects. Simulator platform accelerations vs. time are recorded with each ride at its equal discomfort gain setting. The equal discomfort platform acceleration recordings are then digitzed.

  4. Serum troponin I measurement of subjects exposed to the Taser X-26.

    Science.gov (United States)

    Sloane, Christian M; Chan, Theodore C; Levine, Saul D; Dunford, James V; Neuman, Tom; Vilke, Gary M

    2008-07-01

    The Taser is a high-voltage, low-amperage conducted energy device used by many law enforcement agencies as a less lethal force weapon. The objective of this study was to evaluate for a rise in serum troponin I level after deployment of the Taser on law enforcement training volunteers. A prospective, observational cohort study was performed evaluating serum troponin I levels in human subjects 6 h after an exposure to the Taser X-26. Outcome measures included abnormal elevation in serum troponin I level (> 0.2 ng/mL). There were 66 subjects evaluated. The mean shock duration was 4.36 s (range 1.2-5 s). None of the subjects had a positive troponin I level 6 h after exposure. It was concluded that human volunteers exposed to a single shock from the Taser did not develop an abnormal serum troponin I level 6 h after shock, suggesting that there was no myocardial necrosis or infarction.

  5. The subjective handicap of epilepsy. A new approach to measuring treatment outcome.

    Science.gov (United States)

    O'Donoghue, M F; Duncan, J S; Sander, J W

    1998-02-01

    It is now widely acknowledged that the impact of epilepsy on the individual extends beyond the occurrence of seizures, and that there is a need for outcome measures sensitive to these consequences. Until now these instruments have largely been developed within a 'quality of life' framework. The technical and conceptual difficulties that arise with measuring quality of life have led us to develop a more focused measurement model, the 'Subjective Handicap of Epilepsy' (SHE) scale, based on the World Health Organization's concept of handicap. The scale contains 32 items in six subscales: 'Work and activities' (eight items), 'Social and personal' (four items), 'Self-perception' (five items), 'Physical' (four items), 'Life-satisfaction' (four items) and a 'Change' scale (seven items); and it takes on average handicapping effects of increasing seizure frequency, employment status, the impact of epilepsy on career choice and the subject's own opinion as to the major determinant of their quality of life. The scales were also sensitive, retrospectively, to the benefits of successful epilepsy surgery in a cohort of 105 patients. Scales focusing specifically on handicap were more sensitive to group differences in seizure frequency in the clinic population, and to outcome after epilepsy surgery, than the 'Life-satisfaction' scale and the Epilepsy Surgery Inventory 55 (ESI-55) scales. This supports the contention that measuring 'subjective handicap' may be a more sensitive, and more useful, approach to assessing the impact of interventions on the long-term consequences of epilepsy than current methods.

  6. Trismus following different treatment modalities for head and neck cancer: a systematic review of subjective measures.

    Science.gov (United States)

    Loh, Sook Y; Mcleod, Robert W J; Elhassan, Hassan A

    2017-07-01

    The aim of this review was to compare systematically the subjective measure of trismus between different interventions to treat head and neck cancer, particularly those of the oropharynx. Using The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) Guidelines, Six databases were searched for the text using various terms which include "oropharyngeal/head and neck cancer", "trismus/mouth opening" and the various treatment modalities. Included in the review were clinical studies (> or =10 patients). Three observers independently assessed the papers identified. Among the six studies reviewed, five showed a significantly worst outcome with regard to the quality-of-life questionnaire scores for a radiotherapy or surgery and radiotherapy (RT) ± chemotherapy or chemoradiotherapy when compared to surgery alone. Only one study showed no significant difference between surgery alone and other treatment modalities. Subjective quality-of-life measures are a concurrent part of modern surgical practice. Although subjective measures were utilised to measure post operative trismus successfully, there was no consensus as to which treatment modality had overall better outcomes, with conflicting studies in keeping with the current debate in this field. Larger and higher quality studies are needed to compare all three treatment modalities.

  7. The influence of negative mood on heart rate complexity measures and baroreflex sensitivity in healthy subjects.

    Science.gov (United States)

    Köbele, Ralf; Koschke, Mandy; Schulz, Steffen; Wagner, Gerd; Yeragani, Shravya; Ramachandraiah, Chaitra T; Voss, Andreas; Yeragani, Vikram K; Bär, Karl-Jürgen

    2010-01-01

    Decreased cardiac vagal function is linked with increased cardiac mortality and depression is associated with decreased heart rate variability. We have previously shown that the Mood Induction Procedure (MIP) in healthy subjects alters pain perception and thalamic activity during pain perception. To study the effect of negative emotion on heart rate variability and complexity measures as well as on baroreceptor sensitivity, as these parameters reflect cardiac autonomic function. We studied 20 healthy female controls before and after neutral MIP and 20 healthy female subjects before and after negative MIP. We investigated measures of valence of mood, heart rate variability and complexity and the baroreceptor sensitivity index. While there was a significant difference in the valence of mood between the neutral and the negative effect condition, there were no significant differences in any of the heart rate or baroreceptor sensitivity measures between the two groups. Our findings did not show any significant influence of acute negative MIP on heart rate variability and complexity measures and baroreceptor sensitivity, even though depressive disorder and stress are associated with decreased heart rate variability. These findings are discussed in the context of clinical depression and anxiety and the increased risk for cardiac mortality. In contrast to the presented results here, we have previously shown that MIP in healthy subjects alters pain perception and thalamic activity.

  8. Understanding excess skin in postbariatric patients: objective measurements and subjective experiences.

    Science.gov (United States)

    Biörserud, Christina; Olbers, Torsten; Staalesen, Trude; Elander, Anna; Olsén, Monika Fagevik

    2016-08-01

    Excess skin is a well-known side effect of massive weight loss after bariatric surgery. However, there is a lack of longitudinal follow-ups. The primary aims of this study were to investigate the development and amount of excess skin after laparoscopic Roux-en-Y gastric bypass and to relate objective results to subjective experiences. University hospital. From 2009 to 2012, 200 patients were included and assessed with respect to excess skin before and 18 months after bariatric surgery. Patients were measured according to a standardized protocol and completed a questionnaire regarding their subjective experience of excess skin. A follow-up visit was completed in 149 patients (78%). All ptosis measurements decreased after weight reduction except for ptosis on the thighs. When comparing objective measurements with patients' subjective experience and discomfort from excess skin, we found little or low correlation in most body parts (rs .03-.67). The prediction analysis indicated that, for every centimeter of ptosis on the abdomen preoperatively, there was a 2-fold greater probability of having a postoperative ptosis on the abdomen of>3 cm (OR = 2.32, 1.76-3.07). The objective measurement of excess skin provides unique information in postbariatric patients' body habitus. Although the measured excess skin decreased compared with preoperative measurements, patients seem to become more aware of and disturbed and discomforted by it after the weight loss. Importantly, the objectively assessed measurements of excess skin correlated fairly with the perceived discomfort. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  9. Effect of a Bluetooth-implemented hearing aid on speech recognition performance: subjective and objective measurement.

    Science.gov (United States)

    Kim, Min-Beom; Chung, Won-Ho; Choi, Jeesun; Hong, Sung Hwa; Cho, Yang-Sun; Park, Gyuseok; Lee, Sangmin

    2014-06-01

    The object was to evaluate speech perception improvement through Bluetooth-implemented hearing aids in hearing-impaired adults. Thirty subjects with bilateral symmetric moderate sensorineural hearing loss participated in this study. A Bluetooth-implemented hearing aid was fitted unilaterally in all study subjects. Objective speech recognition score and subjective satisfaction were measured with a Bluetooth-implemented hearing aid to replace the acoustic connection from either a cellular phone or a loudspeaker system. In each system, participants were assigned to 4 conditions: wireless speech signal transmission into hearing aid (wireless mode) in quiet or noisy environment and conventional speech signal transmission using external microphone of hearing aid (conventional mode) in quiet or noisy environment. Also, participants completed questionnaires to investigate subjective satisfaction. Both cellular phone and loudspeaker system situation, participants showed improvements in sentence and word recognition scores with wireless mode compared to conventional mode in both quiet and noise conditions (P Bluetooth-implemented hearing aids helped to improve subjective and objective speech recognition performances in quiet and noisy environments during the use of electronic audio devices.

  10. Comparison between refraction measured by Spot Vision ScreeningTM and subjective clinical refractometry

    OpenAIRE

    Daniela Lima de Jesus; Flávio Fernandes Villela; Luis Fernando Orlandin; Fernando Naves Eiji; Daniel Oliveira Dantas; Milton Ruiz Alves

    2016-01-01

    OBJECTIVE: The purpose of this study was to evaluate the accuracy of Spot Vision ScreeningTM as an autorefractor by comparing refraction measurements to subjective clinical refractometry results in children and adult patients. METHODS: One-hundred and thirty-four eyes of 134 patients were submitted to refractometry by Spot and clinical refractometry under cycloplegia. Patients, students, physicians, staff and children of staff from the Hospital das Clínicas (School of Medicine, University of...

  11. Analysis of the Precautionary Saving Motive Based on a Subjective Measure : (SAVE 2005-2007)

    OpenAIRE

    Ziegelmeyer, Michael

    2009-01-01

    The importance of the precautionary saving motive for households’ saving behaviour is unquestioned in the literature of the last two decades. However, the magnitude of precautionary savings and its influencing factors could not be satisfactorily determined. A subjective measure of the desired amount of precautionary savings in the German SAVE study 2005-2007 allows for the evaluation of these questions on a new basis without relying on a specific definition of wealth. This study supports the ...

  12. Nasolabial fold angle measurement using anterior segment optical coherence tomography in normal subjects.

    Science.gov (United States)

    Lim, Marcus C C; Aung, Han T; Aung, Tin; Looi, Audrey L G

    2009-01-01

    The human nasolabial fold angle (NFA) has been measured using MRI and photogrammetry and has been shown to decrease with age. The authors aimed to evaluate a novel method using optical coherence tomography to measure the NFA. In this cross-sectional observational series, the authors used anterior segment optical coherence tomography (ASOCT) to image the NFA of both cheeks of 126 subjects aged 21 to 79 years. A dental vinylpolysiloxane custom-designed mould was used as a chin rest. The mean of 3 scans on each side was calculated and analysis of variance, multiple comparisons, and multiple linear regression were carried out using SPSS 11.0. Sixty-one subject (48.4%) were men and 65 (51.6%) were women. Mean age was 50.6 +/- 16.8 years (range, 21-79 years). The ASOCT successfully imaged the NFA in all subjects. Mean right and left NFA were 144.4 degrees +/- 17.1 degrees and 145.4 degrees +/- 17.7 degrees. The NFA were dissimilar between the 6 age categories by decade (p NFA, accounting for 55% of NFA variation. Every year accounted for a decrease of 0.78 degrees (p NFA of 5.4 degrees (p = 0.007) and 4.0 degrees (p = 0.06) in the right and left cheeks, respectively. The NFA decreases with age and increases with male sex and can be measured with ASOCT accurately and easily.

  13. Can subjective comfort be used as a measure of plantar pressure in football boots?

    Science.gov (United States)

    Okholm Kryger, Katrine; Jarratt, Vicky; Mitchell, Séan; Forrester, Steph

    2017-05-01

    Comfort has been shown to be the most desired football boot feature by players. Previous studies have shown discomfort to be related to increased plantar pressures for running shoes which, in some foot regions, has been suggested to be a causative factor in overuse injuries. This study examined the correlation between subjective comfort data and objective plantar pressure for football boots during football-specific drills. Eight male university football players were tested. Plantar pressure data were collected during four football-specific movements for each of three different football boots. The global and local peak pressures based on a nine-sectioned foot map were compared to subjective comfort measures recorded using a visual analogue scale for global discomfort and a discomfort foot map for local discomfort. A weak (rs = -0.126) yet significant (P comfort. The model only significantly predicted (P > 0.001) the outcome for two (medial and lateral forefoot) of the nine foot regions. Subjective comfort data is therefore not a reliable measure of increased plantar pressures for any foot region. The use of plantar pressure measures is therefore needed to optimise injury prevention when designing studded footwear.

  14. Adaptation profiles comprising objective and subjective measures in fibromyalgia: the al-Ándalus project.

    Science.gov (United States)

    Estévez-López, Fernando; Segura-Jiménez, Víctor; Álvarez-Gallardo, Inmaculada C; Borges-Cosic, Milkana; Pulido-Martos, Manuel; Carbonell-Baeza, Ana; Aparicio, Virginia A; Geenen, Rinie; Delgado-Fernández, Manuel

    2017-11-01

    The aim of this study was to identify subgroups in terms of adaptation to FM and to test differences in FM severity between these subgroups. The al-Ándalus project made it possible to perform a comprehensive population-based cross-sectional study in 486 FM patients including multiple assessments of modifiable (could be targeted in therapy) resilience and vulnerability factors, measured by objective and subjective assessments, related to psychological and physical function. FM severity was assessed by means of FM impact (total score of the Revised Fibromyalgia Impact Questionnaire) and distress (Polysymptomatic Distress Scale of the modified 2011 preliminary criteria for FM). Exploratory factor analysis, cluster analysis and analysis of variance were conducted. Factor analysis yielded eight factors: three included objective measures (declarative memory, active lifestyle and objective physical fitness) and five included subjective measures (fatigue, psychological distress, catastrophizing, resilience and subjective physical fitness). Cluster analysis based on these eight factors identified five profiles: Adapted (16%), Fit (18%), Poor performer (20%), Positive (20%) and Maladapted (26%). Most profile comparisons revealed different levels of FM severity varying from Adapted (the most favourable profile) to Maladapted (the most unfavourable profile) with Fit, Poor performer and Positive obtaining intermediate positions. Heterogeneity of FM was shown by five clinically meaningful profiles of modifiable factors that were associated with FM severity. It is of clinical interest to examine whether these profiles are associated with FM prognosis and the effectiveness of interventions, which would enhance the development of customized interventions based on adaptation profiles in FM.

  15. Digital Workload In A Large Radiology Department

    Science.gov (United States)

    Goodsitt, Mitchell M.; Bauman, Roger A.; Lodwick, Gwilym S.

    1986-06-01

    As Radiology becomes more invested in direct digital imaging techniques, the potential for moving these images throughout the department, interpreting them directly in digital mode and archiving them in computer form is a topic of high current interest. A fundamental consideration is the amount of digital data to be handled. Even the low and medium resolution images now handled in digital mode require immense amounts of digital storage space. The first quantification of the amount of digital data was by Dwyer, et al, in a report concerning the workload in a 614-bed hospital. Their assumptions and calculations are reviewed and applied to the workload data from a 1082-bed hospital. Storage requirements for PET and MRI workload are calculated, and an estimate of digital radiography data is presented. The digitization of plain film radiographs will virtually increase the storage requirements by a factor of 10.

  16. The sensitivity of Galvanic Skin Response for assessing mental workload in Indonesia.

    Science.gov (United States)

    Widyanti, Ari; Muslim, Khoirul; Sutalaksana, Iftikar Zahedi

    2017-01-01

    Objective measures have been shown to be equally sensitive in different cultures. However, these measures need special devices that are relatively expensive and need expertise to analyze the result. In Indonesia, there is a need for a sensitive and affordable mental workload measure. To evaluate the sensitivity of Galvanic Skin Response (GSR) in assessing mental workload in Indonesia. A total of 72 Indonesian students with normal visual capability. Participants were asked to work on visual memory search task with a secondary task of counting with three different levels of difficulty. GSR, Heart Rate Variability (HRV), and the NASA-TLX were administered prior to, during, and after the tasks. GSR measure was compared to NASA-TLX and HRV measures. Like the HRV, GSR showed to be sensitive in distinguishing rest and task condition significantly but not sensitive in distinguishing different levels of mental workload. In contrast, both the NASA-TLX and performance measure were sensitive in differentiating different levels of mental workload. GSR has potential as a simple, cost-effective tool for measuring mental workload in Indonesia.

  17. Comparison of different pointing methods for sound localizability measurement in the vision impaired subjects.

    Science.gov (United States)

    Fujii, Atsunori; Ohsugi, Yudai; Yamamoto, Yuki; Nakamura, Takabun; Sugiura, Toshifumi; Tauchi, Masaki

    2007-05-01

    In order to find out the most suitable and accurate pointing methods to study the sound localizability of persons with visual impairment, we compared the accuracy of three different pointing methods for indicating the direction of sound sources in a semi-anechoic dark room. Six subjects with visual impairment (two totally blind and four with low vision) participated in this experiment. The three pointing methods employed were (1) directing the face, (2) directing the body trunk on a revolving chair and (3) indicating a tactile cue placed horizontally in front of the subject. Seven sound emitters were arranged in a semicircle 2.0 m from the subject, 0 degrees to +/-80 degrees of the subject's midline, at a height of 1.2 m. The accuracy of the pointing methods was evaluated by measuring the deviation between the angle of the target sound source and that of the subject's response. The result was that all methods indicated that as the angle of the sound source increased from midline, the accuracy decreased. The deviations recorded toward the left and the right of midline were symmetrical. In the whole frontal area (-80 degrees to +80 degrees from midline), both the tactile cue and the body trunk methods were more accurate than the face-pointing method. There was no significant difference in the center (-40 degrees to +40 degrees from midline). In the periphery (-80 degrees and +80 degrees ), the tactile cue pointing method was the most accurate of all and the body trunk method was the next best. These results suggest that the most suitable pointing methods to study the sound localizability of the frontal azimuth for subjects who are visually impaired are the tactile cue and the body trunk methods because of their higher accuracy in the periphery.

  18. The Evolution of Eupathics: The Historical Roots of Subjective Measures of Wellbeing

    Directory of Open Access Journals (Sweden)

    Erik Angner

    2011-01-01

    Full Text Available

    This paper traces the historical roots of subjective measures of wellbeing, that is, measures designed to represent happiness, satisfaction, or other “positive” or desirable mental states. While it is often suggested that these measures are a modern invention, I argue that they have a long and rich history that conforms to Theodore M. Porter’s general account of measurement in social and behavioral science. Subjective measures emerged in marital success studies, educational psychology, and personality psychology in the 1920s and 30s, and were further shaped by the epidemiology of mental health, gerontology, and the social indicator movement in the 1960s and 70s. Consistent with Porter’s account, these measures emerged in applied rather than theoretical branches of social and behavioral science, and they did so not as a result of physics envy, but rather as a result of a moral impulse to improve society; quantification was intended to make up for perceived deficiencies in unaided human judgment; and radical disagreements about the nature of wellbeing did not impede efforts to measure it – indeed, in time, there was considerably more agreement about how to measure wellbeing than about how to define it.

  19. The reliability of side to side measurements of upper extremity activity levels in healthy subjects

    Directory of Open Access Journals (Sweden)

    Amasay Tal

    2010-07-01

    Full Text Available Abstract Background In both clinical and occupational settings, ambulatory sensors are becoming common for assessing all day measurements of arm motion. In order for the motion of a healthy, contralateral side to be used as a control for the involved side, the inherent side to side differences in arm usage must be minimal. The goal of the present study was to determine the reliability of side to side measurements of upper extremity activity levels in healthy subjects. Methods Thirty two subjects with no upper extremity pathologies were studied. Each subject wore a triaxial accelerometer on both arms for three and a half hours. Motion was assessed using parameters previously reported in the literature. Side to side differences were compared with the intraclass correlation coefficient, standard error of the mean, minimal detectable change scores and a projected sample size analysis. Results The variables were ranked based on their percentage of minimal detectable change scores and sample sizes needed for paired t-tests. The order of these rankings was found to be identical and the top ranked parameters were activity counts per hour (MDC% = 9.5, n = 5, jerk time (MDC% = 15.8, n = 8 and percent time above 30 degrees (MDC% = 34.7, n = 9. Conclusions In general, the mean activity levels during daily activities were very similar between dominant and non-dominant arms. Specifically, activity counts per hour, jerk time, and percent time above 30 degrees were found to be the variables most likely to reveal significant difference or changes in both individuals and groups of subjects. The use of ambulatory measurements of upper extremity activity has very broad uses for occupational assessments, musculoskeletal injuries of the shoulder, elbow, wrist and hand as well as neurological pathologies.

  20. Measurements of potential differences in human subjects induced by motion in a superconducting magnetic field.

    Science.gov (United States)

    Frinak, S; Knight, R A; Liboff, A R

    1992-01-01

    We have attempted to measure the electromotive forces (emfs) induced in human beings moving at a constant speed in a highly dense magnetic field. Experiments were initially conducted on a set of models, and then directly on human subjects. The models consisted of single circular loops of Tygon tubing (I.D., 0.635 cm; O.D., 0.9525 cm) filled with normal saline solution, with circumferences of 20, 40, 60, 80, and 100 cm. The models were connected to an amplifier via silver/silver-chloride electrodes. Each saline loop was mounted on a movable platform, with the plane of the loop perpendicular to the platform's axis; the platform was enabled to move at known constant speeds into and out of the bore of a 1.89-T magnet. The human subjects were then substituted for the saline loops, with the long axis parallel to the direction of motion, and with standard EKG electrodes placed at 180 degrees successively on the ankle, calf, lower thigh, upper thigh, chest, and head. In all cases, for human subjects and models, the peak induced voltage was directly proportional to the speed of movement and the square of the circumference of the bounded cross-sectional areas. Thus, for the saline loops, the correlation coefficient between induced voltage and circumference was .998, and for human subjects, .947. Under the loose assumption that for equal circumferences the bounded areas in human subjects were equal to those in the circular loops, the induced emfs in human subjects were consistently about 13% greater than those in the loops. At a mean speed of 1.18 m/s, the chest had a peak induced voltage of 260 mV, while the voltage at the ankle had a peak of 19.8 mV. The experimental data were used to estimate the corresponding induced-current density at the pericardium, 17 mA/m2. We conclude for a human subject moving at constant speed along the body's long axis into a magnetic field that Faraday's law is closely followed for various cross-sections of the body. Further, in those cases in

  1. Validation of subject-specific cardiovascular system models from porcine measurements.

    Science.gov (United States)

    Revie, James A; Stevenson, David J; Chase, J Geoffrey; Hann, Christopher E; Lambermont, Bernard C; Ghuysen, Alexandre; Kolh, Philippe; Shaw, Geoffrey M; Heldmann, Stefan; Desaive, Thomas

    2013-02-01

    A previously validated mathematical model of the cardiovascular system (CVS) is made subject-specific using an iterative, proportional gain-based identification method. Prior works utilised a complete set of experimentally measured data that is not clinically typical or applicable. In this paper, parameters are identified using proportional gain-based control and a minimal, clinically available set of measurements. The new method makes use of several intermediary steps through identification of smaller compartmental models of CVS to reduce the number of parameters identified simultaneously and increase the convergence stability of the method. This new, clinically relevant, minimal measurement approach is validated using a porcine model of acute pulmonary embolism (APE). Trials were performed on five pigs, each inserted with three autologous blood clots of decreasing size over a period of four to five hours. All experiments were reviewed and approved by the Ethics Committee of the Medical Faculty at the University of Liege, Belgium. Continuous aortic and pulmonary artery pressures (P(ao), P(pa)) were measured along with left and right ventricle pressure and volume waveforms. Subject-specific CVS models were identified from global end diastolic volume (GEDV), stroke volume (SV), P(ao), and P(pa) measurements, with the mean volumes and maximum pressures of the left and right ventricles used to verify the accuracy of the fitted models. The inputs (GEDV, SV, P(ao), P(pa)) used in the identification process were matched by the CVS model to errors pressures not used to fit the model compared experimental measurements to median absolute errors of 4.3% and 4.4%, which are equivalent to the measurement errors of currently used monitoring devices in the ICU (∼5-10%). These results validate the potential for implementing this approach in the intensive care unit. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. A new device for measuring resting energy expenditure (REE) in healthy subjects.

    Science.gov (United States)

    Malavolti, Marcella; Pietrobelli, Angelo; Dugoni, Manfredo; Poli, Marco; Romagnoli, Elisa; De Cristofaro, Paolo; Battistini, Nino C

    2007-06-01

    Lifestyle change targeted towards increasing daily resting energy expenditure (REE) is one of the cornerstones of obesity treatment. Measurements of energy expenditure and substrate utilization are essential to understanding the metabolic basis of obesity, and the physiological responses to perturbations in habitual food intake. REE is the largest part of human energy expenditure (60-70%) and an increase or decrease in REE would have a large impact on total energy. Accurate and easy-to-use methods for measuring REE are needed, to be applied by clinicians in daily clinical settings to assess the validity of a new instrument to estimate REE in normal weight, healthy adults. Ninety-nine subjects (52 females and 47 males) (mean+/-SD, age 38+/-14 years; body mass index (BMI) 23+/-3 kg/m(2)) were tested. REE was assessed using a Sensor Medics Vmax metabolic cart with a ventilated canopy and with the SenseWear armband. Body composition, percentage fat mass (%FM) and percentage fat free mass (%FFM) were assessed by skinfold thickness measurements (SF), bio-electrical impedance analysis (BIA) and air displacement plethysmography (BOD-POD). No significant difference was found among measurements of FFM using the three different techniques. Both SenseWear and Sensor Medics Vmax showed a high correlation, r=0.42 and r=0.40 (pBOD-POD correlated with SenseWear (r=0.42, pBOD-POD provide valid and reliable measurements of FFM. Our results suggest that the SenseWear armband is an acceptable device to accurately measure REE in healthy subjects. Its characteristics have the potential to reduce measurement times and make the SenseWear armband useful for epidemiological studies.

  3. Is there an association between subjective and objective measures of cognitive function in patients with affective disorders?

    DEFF Research Database (Denmark)

    Svendsen, Anne M; Kessing, Lars V; Munkholm, Klaus

    2012-01-01

    Background: Patients with affective disorders experience cognitive dysfunction in addition to their affective symptoms. The relationship between subjectively experienced and objectively measured cognitive function is controversial with several studies reporting no correlation between subjective...... and objective deficits. Aims: To investigate whether there is a correlation between subjectively reported and objectively measured cognitive function in patients with affective disorders, and whether subjective complaints predict objectively measured dysfunction. Methods: The study included 45 participants; 15...... with bipolar disorder (BD), 15 with unipolar disorder (UD) and 15 healthy individuals. Participants' subjectively experienced cognitive function and objective cognitive function were assessed with the Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire (CPFQ) and the Screen...

  4. Measuring executive function in control subjects and TBI patients with question completion time (QCT).

    Science.gov (United States)

    Woods, David L; Yund, E William; Wyma, John M; Ruff, Ron; Herron, Timothy J

    2015-01-01

    Questionnaire completion is a complex task that places demands on cognitive functions subserving reading, introspective memory, decision-making, and motor control. Although computerized questionnaires and surveys are used with increasing frequency in clinical practice, few studies have examined question completion time (QCT), the time required to complete each question. Here, we analyzed QCTs in 172 control subjects and 31 patients with traumatic brain injury (TBI) who completed two computerized questionnaires, the 17-question Post-Traumatic Stress Disorder (PTSD) Checklist (PCL) and the 25-question Cognitive Failures Questionnaire (CFQ). In control subjects, robust correlations were found between self-paced QCTs on the PCL and CFQ (r = 0.82). QCTs on individual questions correlated strongly with the number of words in the question, indicating the critical role of reading speed. QCTs increased significantly with age, and were reduced in females and in subjects with increased education and computer experience. QCT z-scores, corrected for age, education, computer use, and sex, correlated more strongly with each other than with the results of other cognitive tests. Patients with a history of severe TBI showed significantly delayed QCTs, but QCTs fell within the normal range in patients with a history of mild TBI. When questionnaires are used to gather relevant patient information, simultaneous QCT measures provide reliable and clinically sensitive measures of processing speed and executive function.

  5. The kinetic and kinematic stability measures in healthy adult subjects with and without flat foot.

    Science.gov (United States)

    Sung, Paul S; Zipple, J Timothy; Andraka, John M; Danial, Pamela

    2017-03-01

    Flat foot problems are associated with impaired mobility and postural stability. The purpose of this study was to compare the kinematic and kinetic indices during one leg standing between subjects with and without flat foot. Forty-four participants enrolled in the study, including 22 subjects with flat foot and 22 control subjects. The measurements included kinematic stability on the trunk as well as kinetic stability from a force plate. All participants were asked to maintain one leg standing with the contralateral hip and knee flexed to approximately 90° for 25seconds. The kinetic index decreased in the flat foot group (t=-5.08, p=0.001) during one leg standing without visual input. There were strong correlations between kinetic and kinematic stabilities (0.75-0.86) with visual input and moderate correlations (0.49-0.67) without visual input in the control group. The flat foot group exhibited a significantly decreased kinetic index without visual input. The more effective postural stability in the control group might be due to efficient compensatory strategies utilized without visual input to maintain one leg standing. These outcome measures could help to develop a practical test leading to kinematic postural changes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Subjectively and objectively measured sleep with and without posttraumatic stress disorder and trauma exposure.

    Science.gov (United States)

    Kobayashi, Ihori; Huntley, Edward; Lavela, Joseph; Mellman, Thomas A

    2012-07-01

    Although reports of sleep disturbances are common among individuals with posttraumatic stress disorder (PTSD), results of polysomnographic (PSG) studies have inconsistently documented abnormalities and have therefore suggested "sleep state misperception." The authors' study objectives were to compare sleep parameters measured objectively and subjectively in the laboratory and at home in civilians with and without trauma exposure and PTSD. Cross-sectional study. PSG recordings in a sleep laboratory and actigraphic recordings in participants' homes. One hundred three urban-residing African Americans with and without trauma exposure and PTSD who participated in a larger study. N/A. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], and wake after sleep onset [WASO]) were assessed using laboratory PSG and home actigraphy. A sleep diary was completed in the morning after PSG and actigraphy recordings. Habitual TST, SOL, and WASO were assessed using a sleep questionnaire. The Clinician Administered PTSD Scale was administered to assess participants' trauma exposure and PTSD diagnostic status. Participants, regardless of their trauma exposure/PTSD status, underestimated WASO in the diary and questionnaire relative to actigraphy and overestimated SOL in the diary relative to PSG. Among participants with current PTSD, TST diary estimates did not differ from the actigraphy measure in contrast with those without current PTSD who overestimated TST. No other significant group differences in discrepancies between subjective and objective sleep measures were found. Discrepancies between subjectively and objectively measured sleep parameters were not associated with trauma exposure or PTSD. This challenges prior assertions that individuals with PTSD overreport their sleep disturbances.

  7. A review of subjective impact measures for use with children and adolescents with epilepsy.

    Science.gov (United States)

    Cowan, Justin; Baker, Gus A

    2004-10-01

    To evaluate measures of epilepsy-specific impact currently available for use with children and adolescents. The relative merits of the different measures are examined. Four published epilepsy-specific impact measures, the Epilepsy and Learning Disabilities Quality of Life Scale (ELDQOL), the Health-related Quality of Life in Children with Epilepsy (HRQoLCE); the Impact of Childhood Neurologic Disability Scale (ICND), the Quality of Life in Epilepsy Inventory for Adolescents (QOLIE-AD-48), and the Quality of Life for Children with Epilepsy (QOLCE) were reviewed. There exist several shortcomings with the available measures on various psychometric criteria with not one of the currently available measures reaching acceptable psychometric standards in terms of reliability and validity. Of note are the particular inadequacies in the validation of scale content; with there being no investigation of the existence of age or ability effects for the items in any of the questionnaires reviewed. There is a clear demand for a psychometrically robust measure of subjective impact of epilepsy for children and adolescents, which is applicable to a wide age and ability range. At present, the efforts of the Canadian Pediatric Epilepsy Network with the recent publication of a novel measure holds much promise for the future. It is advocated that further efforts are made to further establish the psychometric properties of these scales and for their integration within a comprehensive outcome model for use in the evaluation of clinical interventions.

  8. Subjective and objective measurement of websites quality in a chemical industry

    Directory of Open Access Journals (Sweden)

    Julius Jillbert

    2014-10-01

    Full Text Available This paper assesses the Website of a chemical company, Deza, relative to strategy and Website quality. In an attempt to obtain both an objective and subjective measure of the quality of the Deza website, two assessment methods have been used. Firstly, a subjective assessment was conducted based on the WebQual survey instrument proposed by Barnes and Vidgen (2000. Secondly, a more objective assessment was conducted via an “informational content analysis”, based on the work of Carlson et. al. (2001. Analysis of the results of the WebQual survey suggest that overall, the Deza Website is perceived by the user as being of a higher quality than the Koppers Website, but a lower quality then the Nalon Website. The Information content analysis also ranks the Deza website as being superior to Koppers and inferior to Nalon.

  9. Is aerobic workload positively related to ambulatory blood pressure? A cross-sectional field study among cleaners.

    Science.gov (United States)

    Korshøj, Mette; Clays, Els; Lidegaard, Mark; Skotte, Jørgen H; Holtermann, Andreas; Krustrup, Peter; Søgaard, Karen

    2016-01-01

    Cardiovascular disease is prevalent among workers with high levels of occupational physical activity. The increased risk may be due to a high relative aerobic workload, possibly leading to increased blood pressure. However, studies investigating the relation between relative aerobic workload and ambulatory blood pressure (ABP) are lacking. The aim was to explore the relationship between objectively measured relative aerobic workload and ABP. A total of 116 cleaners aged 18-65 years were included after informed consent was obtained. A portable device (Spacelabs 90217) was mounted for 24-h measurements of ABP, and an Actiheart was mounted for 24-h heart rate measurements to calculate relative aerobic workload as percentage of relative heart rate reserve. A repeated-measure multi-adjusted mixed model was applied for analysis. A fully adjusted mixed model of measurements throughout the day showed significant positive relations (p < 0.001): a 1% increase in mean relative aerobic workload was associated with an increase of 0.42 ± 0.05 mmHg (95% CI 0.32-0.52 mmHg) in systolic ABP and 0.30 ± 0.04 mmHg (95% CI 0.22-0.38 mmHg) in diastolic ABP. Correlations between relative aerobic workload and ABP were significant. Because workers may have an elevated relative aerobic workload for several hours each working day, this relationship may elucidate a mechanism behind the increased risk for cardiovascular disease among workers exposed to high levels of occupational physical activity.

  10. Comparison of subjective and fully automated methods for measuring mammographic density.

    Science.gov (United States)

    Moshina, Nataliia; Roman, Marta; Sebuødegård, Sofie; Waade, Gunvor G; Ursin, Giske; Hofvind, Solveig

    2018-02-01

    Background Breast radiologists of the Norwegian Breast Cancer Screening Program subjectively classified mammographic density using a three-point scale between 1996 and 2012 and changed into the fourth edition of the BI-RADS classification since 2013. In 2015, an automated volumetric breast density assessment software was installed at two screening units. Purpose To compare volumetric breast density measurements from the automated method with two subjective methods: the three-point scale and the BI-RADS density classification. Material and Methods Information on subjective and automated density assessment was obtained from screening examinations of 3635 women recalled for further assessment due to positive screening mammography between 2007 and 2015. The score of the three-point scale (I = fatty; II = medium dense; III = dense) was available for 2310 women. The BI-RADS density score was provided for 1325 women. Mean volumetric breast density was estimated for each category of the subjective classifications. The automated software assigned volumetric breast density to four categories. The agreement between BI-RADS and volumetric breast density categories was assessed using weighted kappa (k w ). Results Mean volumetric breast density was 4.5%, 7.5%, and 13.4% for categories I, II, and III of the three-point scale, respectively, and 4.4%, 7.5%, 9.9%, and 13.9% for the BI-RADS density categories, respectively ( P for trend density categories was k w  = 0.5 (95% CI = 0.47-0.53; P density increased with increasing density category of the subjective classifications. The agreement between BI-RADS and volumetric breast density categories was moderate.

  11. Workload Management Strategies for Online Educators

    Science.gov (United States)

    Crews, Tena B.; Wilkinson, Kelly; Hemby, K. Virginia; McCannon, Melinda; Wiedmaier, Cheryl

    2008-01-01

    With increased use of online education, both students and instructors are adapting to the online environment. Online educators must adjust to the change in responsibilities required to teach online, as it is quite intensive during the designing, teaching, and revising stages. The purpose of this study is to examine and update workload management…

  12. Parameters and sensitivity in workload control

    NARCIS (Netherlands)

    Land, M.J.

    2006-01-01

    Both practitioners and scientists have recognized the importance of workload control (WLC) for job shop practices. WLC principles have been integrated into a comprehensive concept, which receives a lot of attention in scientific literature in recent years. Though meant as a robust concept for

  13. Exploring Individual Differences in Workload Assessment

    Science.gov (United States)

    2014-12-26

    Mark H. Chignell. "Mental Workload Dynamics in Adaptive Interface Design." IEEE Transactions on Systems, Man and Cybernetics 18, no. 4 (1988): 647-658...J. Colombi, D. Jacques, and J. Miller. "Human Systems Integration within the DOD Architecture Framework." IIE Annual Conference and Expo

  14. Dynamic workload peak detection for slack management

    NARCIS (Netherlands)

    Milutinovic, A.; Goossens, Kees; Smit, Gerardus Johannes Maria; Kuper, Jan; Kuper, J.

    2009-01-01

    In this paper an analytical study on dynamism and possibilities on slack exploitation by dynamic power management is presented. We introduce a specific workload decomposition method for work required for (streaming) application processing data tokens (e.g. video frames) with work behaviour patterns

  15. Beyond standard quality of life measures: the subjective experiences of living with inflammatory bowel disease.

    Science.gov (United States)

    Wolfe, Barat J; Sirois, Fuschia M

    2008-08-01

    In order to facilitate our understanding of health-related quality of life (HRQoL) for inflammatory bowel disease (IBD) patients, it is critical to explore their subjective experiences with the disease. Research has suggested that current modes of assessing HRQoL (i.e., generic and disease-specific measures) may not fully represent all dimensions of patients' HRQoL. The purpose of this study was to examine IBD patients' subjective experiences of the daily impact of IBD, and categorize dimensions of their HRQoL affected by IBD, as identified by the patients themselves. Two hundred and eighty-two patients with IBD provided answers to the qualitative question "How has IBD affected your daily activities?" A content analysis using NVivo 2.0 was conducted on the participants' responses to this question to reveal dimensions of their HRQoL. The analysis yielded six dimensions and several subdimensions of HRQoL, including physical (systemic functioning, daily functioning, energy/vitality, pain), emotional, social, cognitive (functioning, attending to disease), self-regulation (taking control, loss of control, and neutral), and practical functioning. These results reflect previous findings, but also reveal several dimensions of HRQoL not included in current measures of HRQoL for IBD patients (i.e., cognitive, self-regulation, and practical). The implications of these findings for future measurement of HRQoL and research with IBD patients are discussed.

  16. Measurement of cortisol and testosterone in hair of obese and non-obese human subjects.

    Science.gov (United States)

    Chan, J; Sauvé, B; Tokmakejian, S; Koren, G; Van Uum, S

    2014-06-01

    Hair analysis has been demonstrated to accurately reflect exposure to drug abuse, environmental toxins and exogenous hormones. We tested the feasibility of measuring cortisol and testosterone in hair of healthy and obese subjects. A modified immunoassay (ELISA) originally developed for saliva was used. Hair, urine and blood samples were collected from young non-obese and obese patients. Perceived stress (PSS) was measured using a validated questionnaire. There was no difference in PSS between non-obese and obese subjects. Hair cortisol levels were significantly correlated with weight (r = 0.27, p significance (p = 0.063). Hair cortisol levels did not correlate with age or urinary cortisol. There was a negative correlation between hair testosterone and age (r = -0.47, p significance (p = 0.098). The ratio of hair cortisol over hair testosterone (C/T) was higher in the obese group than in the young non-obese group. The C/T ratio correlated positively with age (r = 0.56, p significance. Hair cortisol levels increase, while hair testosterone levels decrease with obesity. The hair C/T ratio was significantly correlated with age, BMI and waist circumference better than hair cortisol or testosterone alone. As hair collection is non-invasive and is not influenced by moment-to-moment variations, the measurement of hormones in hair is a useful tool in research and possibly clinical practice. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Translating data and measurements from stratus to cirrus OCT in glaucoma patients and healthy subjects.

    Science.gov (United States)

    Chiseliţă, Dorin; Pantalon, Anca Delia; Cantemir, Alina; Gălăţanu, Cătălina

    2016-01-01

    Aim: our study tried to find a mathematical conversion method of the measurements obtained in Time Domain (TD) OCT to Spectral Domain (SD) OCT. Material and method: A prospective randomized, double blind study that included 244 eyes, from 121 patients (normal subjects, glaucoma suspects, glaucoma), in whom we analyzed the retinal nerve fiber layer (RNFL) and the optic disc in the same session by using TD OCT (Stratus) and SD OCT (Cirrus), was performed. The means for RNFL thickness (overall value and per quadrants), neural area and cup/ disc (C/ D) ratio, were measured. Results: We found statistically significant differences between parameters measured in TD OCT and SD OCT (pOCT machines. Data dispersion showed a linear relation between measurements. One can use the following mathematical equations for conversion: Mean RNFL (Cirrus) = 15.77 + 0.748 x Mean RNFL (Stratus) Mean neural area (Cirrus) = 0.508 + 0.388 x Mean neural area (Stratus) Mean C/ D ratio (Cirrus) = 0.157 + 0.792 x Mean C/ D (Stratus) Conclusions: data based on our calculated mathematical conversion equations can be converted into SD OCT. Therefore, we offered a useful tool for the long term monitoring of our patients although the initial measurements in TD OCT made comparisons for patients later measured with SD OCT impossible. Abbreviations: RNFL = retinal nerve fiber layer, TD OCT = time domain optical coherence tomography, SD OCT = spectral domain optical coherence tomography, VF = visual field, CI = confidence interval, ISNT segments = inferior, superior, nasal, temporal segment.

  18. Measurements of exhaled nitric oxide in healthy subjects age 4 to 17 years

    DEFF Research Database (Denmark)

    Buchvald, Frederik; Baraldi, Eugenio; Carraro, Silvia

    2005-01-01

    NO was measured in healthy subjects of 4 to 17 years according to American Thoracic Society guidelines (single breath online, exhalation flow 50 mL/s) with a chemiluminescence analyzer (NIOX Exhaled Nitric Oxide Monitoring System, Aerocrine, Sweden) in 3 European and 2 US centers. Each child performed 3...... NO in 405 children was 9.7 ppb, and the upper 95% confidence limit was 25.2 ppb. FE NO increased significantly with age, and higher FE NO was seen in children with self-reported rhinitis/conjunctivitis or hay fever. The success rate was age-dependent and improved from 40% in the children 4 years old...

  19. Perception of depth distance of integral photography through the measurement of eye movement and subjective test

    Science.gov (United States)

    Yano, Sumio; Suzuki, Makoto; Park, Min-Chul

    2017-05-01

    We developed a measurement tool for binocular eye movement and examined the perception of depth distance in integral photography images, which is a type of three dimensional image, using the tool we developed. Furthermore, we evaluated the perception of the depth distance in integral photography images by the subjective test, and we considered the perception results of the depth distance, which were these two experimental results. Additionally, we examined the perception of the depth distance in the real objects, and compared with the results in the case of integral photography images and real objects.

  20. Personality dimensions measured by the Temperament and Character Inventory (TCI) in subjects with social phobia.

    Science.gov (United States)

    Marteinsdottir, Ina; Tillfors, Maria; Furmark, Tomas; Anderberg, Ulla Maria; Ekselius, Lisa

    2003-01-01

    The present study investigated personality dimensions by means of the Temperament and Character Inventory (TCI) in subjects with social phobia with or without a co-existing avoidant personality disorder. Thirty-one individuals with social phobia were recruited through advertisement and diagnosed with the Structured Clinical Interview for DSM-IV I and II psychiatric disorders. Comorbid Axis I psychiatric disorders were diagnosed in 29% of the cases. Co-occurring personality disorders were present in 55.8% of the cases, and avoidant personality disorder in 48.4%. The social phobia subjects, as compared to healthy controls of the same age, scored significantly higher in the TCI dimension measuring Harm avoidance but significantly lower in Persistence, Self-directedness, Cooperativeness and Self-transcendence. Presence of avoidant personality disorders in the social phobia subjects was associated with significantly higher Harm avoidance, particularly on the subscale Shyness with strangers. In conclusion, individuals with social phobia were characterized by high comorbidity of avoidant personality disorder and deviations in TCI personality dimensions. Enhanced Harm avoidance was the most prominent personality trait. The observed deviations in TCI dimensions were primarily related to the social phobia itself and not to the presence of concurrent personality disorders.

  1. How do training and competition workloads relate to injury? The workload-injury aetiology model.

    Science.gov (United States)

    Windt, Johann; Gabbett, Tim J

    2017-03-01

    Injury aetiology models that have evolved over the previous two decades highlight a number of factors which contribute to the causal mechanisms for athletic injuries. These models highlight the pathway to injury, including (1) internal risk factors (eg, age, neuromuscular control) which predispose athletes to injury, (2) exposure to external risk factors (eg, playing surface, equipment), and finally (3) an inciting event, wherein biomechanical breakdown and injury occurs. The most recent aetiological model proposed in 2007 was the first to detail the dynamic nature of injury risk, whereby participation may or may not result in injury, and participation itself alters injury risk through adaptation. However, although training and competition workloads are strongly associated with injury, existing aetiology models neither include them nor provide an explanation for how workloads alter injury risk. Therefore, we propose an updated injury aetiology model which includes the effects of workloads. Within this model, internal risk factors are differentiated into modifiable and non-modifiable factors, and workloads contribute to injury in three ways: (1) exposure to external risk factors and potential inciting events, (2) fatigue, or negative physiological effects, and (3) fitness, or positive physiological adaptations. Exposure is determined solely by total load, while positive and negative adaptations are controlled both by total workloads, as well as changes in load (eg, the acute:chronic workload ratio). Finally, we describe how this model explains the load-injury relationships for total workloads, acute:chronic workload ratios and the training load-injury paradox. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Therapeutic misconception in research subjects: development and validation of a measure.

    Science.gov (United States)

    Appelbaum, Paul S; Anatchkova, Milena; Albert, Karen; Dunn, Laura B; Lidz, Charles W

    2012-12-01

    Therapeutic misconception (TM), which occurs when research subjects fail to appreciate the distinction between the imperatives of clinical research and ordinary treatment, may undercut the process of obtaining meaningful consent to clinical research participation. Previous studies have found that TM is widespread, but progress in addressing TM has been stymied by the absence of a validated method for assessing its presence. The goal of this study was to develop and validate a theoretically grounded measure of TM, assess its diagnostic accuracy, and test previous findings regarding TM's prevalence. A total of 220 participants were recruited from clinical trials at four academic medical centers in the United States. Participants completed a 28-item Likert-type questionnaire to assess the presence of beliefs associated with TM, and a semistructured TM interview designed to elicit their perceptions of the nature of the clinical trial in which they were participating. Data from the questionnaires were subjected to factor analysis, and items with poor factor loadings were excluded. This resulted in a 10-item scale, with three strongly correlated factors and excellent internal consistency; the fit indices of the model across 10 training sets were consistent with the original results, suggesting a stable factor solution. The scale was validated against the TM interview, with significantly higher scores among subjects coded as displaying evidence of TM. Receiver operating curve (ROC) analysis based on a 10-fold internal cross-validation yielded area under the ROC (AUC) = 0.682 for any evidence of TM. When sensitivity (0.72) and specificity (0.61) were both optimized, positive predictive value was 0.65 and negative predictive value was 0.68, with a positive likelihood ratio of 1.89 and a negative likelihood ratio of 0.47. In all, 50.5% (n = 101) of the participants manifested evidence of TM on the TM interview, a somewhat lower rate than in most previous studies. The

  3. An investigation of correlation between pilot scanning behavior and workload using stepwise regression analysis

    Science.gov (United States)

    Waller, M. C.

    1976-01-01

    An electro-optical device called an oculometer which tracks a subject's lookpoint as a time function has been used to collect data in a real-time simulation study of instrument landing system (ILS) approaches. The data describing the scanning behavior of a pilot during the instrument approaches have been analyzed by use of a stepwise regression analysis technique. A statistically significant correlation between pilot workload, as indicated by pilot ratings, and scanning behavior has been established. In addition, it was demonstrated that parameters derived from the scanning behavior data can be combined in a mathematical equation to provide a good representation of pilot workload.

  4. Network, anatomical, and non-imaging measures for the prediction of ADHD diagnosis in individual subjects

    Directory of Open Access Journals (Sweden)

    Jason W Bohland

    2012-12-01

    Full Text Available Brain imaging methods have long held promise as diagnostic aids for neuropsychiatric conditions with complex behavioral phenotypes such as Attention-Deficit/Hyperactivity Disorder. This promise has largely been unrealized, at least partly due to the heterogeneity of clinical populations and the small sample size of many studies. A large, multi-center dataset provided by the ADHD-200 Consortium affords new opportunities to test methods for individual diagnosis based on MRI-observable structural brain attributes and functional interactions observable from resting state fMRI. In this study, we systematically calculated a large set of standard and new quantitative markers from individual subject datasets. These features (>12,000 per subject consisted of local anatomical attributes such as cortical thickness and structure volumes and both local and global resting state network measures. Three methods were used to compute graphs representing interdependencies between activations in different brain areas, and a full set of network features was derived from each. Of these, features derived from the inverse of the time series covariance matrix, under an L1-norm regularization penalty, proved most powerful. Anatomical and network feature sets were used individually, and combined with non-imaging phenotypic features from each subject. Machine learning algorithms were used to rank attributes, and performance was assessed under cross-validation and on a separate test set of 168 subjects for a variety of feature set combinations. While non-imaging features gave highest performance in cross-validation, the addition of imaging features in sufficient numbers led to improved generalization to new data. Stratification by gender also proved to be a fruitful strategy to improve classifier performance. We describe the overall approach used, compare the predictive power of different classes of features, and describe the most impactful features in relation to the

  5. Empirical Analysis of the Subjective Impressions and Objective Measures of Domain Scientists’ Analytical Judgment Using Visualizations

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Aritra; Burrows, Susannah M.; Han, Kyungsik; Rasch, Philip J.

    2017-04-15

    Scientists working in a particular domain often adhere to conventional data analysis and presentation methods and this leads to familiarity with these methods over time. But does high familiarity always lead to better analytical judgment? This question is especially relevant when visualizations are used in scientific tasks, as there can be discrepancies between visualization best practices and domain conventions. However, there is little empirical evidence of the relationships between scientists’ subjective impressions about familiar and unfamiliar visualizations and objective measures of their effect on scientific judgment. To address this gap and to study these factors, we focus on the climate science domain, specifically on visualizations used for comparison of model performance. We present a comprehensive user study with 47 climate scientists where we explored the following factors: i) relationships between scientists’ familiarity, their perceived levels of com- fort, confidence, accuracy, and objective measures of accuracy, and ii) relationships among domain experience, visualization familiarity, and post-study preference.

  6. Panel workload assessment in US primary care: accounting for non-face-to-face panel management activities.

    Science.gov (United States)

    Arndt, Brian; Tuan, Wen-Jan; White, Jennifer; Schumacher, Jessica

    2014-01-01

    An understanding of primary care provider (PCP) workload is an important consideration in establishing optimal PCP panel size. However, no widely acceptable measure of PCP workload exists that incorporates the effort involved with both non-face-to-face patient care activities and face-to-face encounters. Accounting for this gap is critical given the increase in non-face-to-face PCP activities that has accompanied electronic health records (EHRs) (eg, electronic messaging). Our goal was to provide a comprehensive assessment of perceived PCP workload, accounting for aspects of both face-to-face and non-face-to-face encounters. Internal medicine, family medicine, and pediatric PCPs completed a self-administered survey about the perceived workload involved with face-to-face and non-face-to-face panel management activities as well as the perceived challenge associated with caring for patients with particular biomedical, demographic, and psychosocial characteristics (n = 185). Survey results were combined with EHR data at the individual patient and PCP service levels to assess PCP panel workload, accounting for face-to-face and non-face-to-face utilization. Of the multiple face-to-face and non-face-to-face activities associated with routine primary care, PCPs considered hospital admissions, obstetric care, hospital discharges, and new patient preventive health visits to be greater workload than non-face-to-face activities such as telephone calls, electronic communication, generating letters, and medication refills. Total workload within PCP panels at the individual patient level varied by overall health status, and the total workload of non-face-to-face panel management activities associated with routine primary care was greater than the total workload associated with face-to-face encounters regardless of health status. We used PCP survey results coupled with EHR data to assess PCP workload associated with both face-to-face as well as non-face-to-face panel management

  7. Measurement of dynamic ocular surface temperature in healthy subjects using a new thermography device.

    Science.gov (United States)

    Klamann, Matthias K J; Maier, Anna-Karina B; Gonnermann, Johannes; Klein, Julian P; Pleyer, Uwe

    2012-08-01

    To investigate the routine use and applicability of a new ocular thermography device (TG 1000; Tomey Corp, Nagoya, Japan) in healthy individuals. Sixty eyes of 30 healthy subjects were included in this prospective study. Intraobserver reproducibility was tested with an ocular surface-oriented infrared radiation thermographic device in a non-contact manner. Using a standard examination protocol, the ocular surface temperature was assessed by dynamic thermal imaging over a time period of 10 s. The procedure was repeated three times during a single session by one examiner. Intraclass correlation coefficients (ICC) were calculated. Ocular surface temperature measurements were highly reproducible. The mean ocular surface temperature was 34.02°C ± 0.22. The ICC was 0.947%, 0.949%, and 0.955% for minimum, maximum, and mean temperatures, respectively. Ocular surface temperature measurements made using the Tomey TG 1000 in healthy subjects showed excellent intraobserver reproducibility. This novel non-invasive technique offers new options for increased understanding of the physiology of the ocular surface.

  8. A Novel Noninvasive Method for Measuring Fatigability of the Quadriceps Muscle in Noncooperating Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Jesper B. Poulsen

    2015-01-01

    Full Text Available Background. Critical illness is associated with muscle weakness leading to long-term functional limitations. Objectives. To assess the reliability of a novel method for evaluating fatigability of the quadriceps muscle in noncooperating healthy subjects. Methods. On two occasions, separated by seven days, nonvoluntary isometric contractions (twitch and tetanic of the quadriceps femoris muscle evoked by transcutaneous electrical muscle stimulation were recorded in twelve healthy adults. For tetanic contractions, the Fatigue Index (ratio of peak torque values and the slope of the regression line of peak torque values were primary outcome measures. For twitch contractions, maximum peak torque and rise time were calculated. Relative (intraclass correlation, ICC3.1 and absolute (standard error of measurement, SEM reliability were assessed and minimum detectable change was calculated using a 95% confidence interval (MDC95%. Results. The Fatigue Index (ICC3.1, 0.84; MDC95%, 0.12 and the slope of the regression line (ICC3.1, 0.99; MDC95%, 0.03 showed substantial relative and absolute reliability during the first 15 and 30 contractions, respectively. Conclusion. This method for assessing fatigability of the quadriceps muscle produces reliable results in healthy subjects and may provide valuable data on quantitative changes in muscle working capacity and treatment effects in patients who are incapable of producing voluntary muscle contractions.

  9. Workload based order acceptance in job shop environments

    NARCIS (Netherlands)

    Ebben, Mark; Hans, Elias W.; Olde Weghuis, F.M.; Olde Weghuis, F.M.

    2005-01-01

    In practice, order acceptance and production planning are often functionally separated. As a result, order acceptance decisions are made without considering the actual workload in the production system, or by only regarding the aggregate workload. We investigate the importance of a good workload

  10. Workload characterization, modeling, and prediction in grid Computing

    NARCIS (Netherlands)

    Li, Hui

    2008-01-01

    Workloads play an important role in experimental performance studies of computer systems. This thesis presents a comprehensive characterization of real workloads on production clusters and Grids. A variety of correlation structures and rich scaling behavior are identified in workload attributes such

  11. Age-related different relationships between ectopic adipose tissues and measures of central obesity in sedentary subjects

    National Research Council Canada - National Science Library

    Guglielmi, Valeria; Maresca, Luciano; D'Adamo, Monica; Di Roma, Mauro; Lanzillo, Chiara; Federici, Massimo; Lauro, Davide; Preziosi, Paolo; Bellia, Alfonso; Sbraccia, Paolo

    2014-01-01

    ... (SAT) were simultaneously measured by Magnetic Resonance Imaging (MRI) and related to waist circumference measurements and age in 32 sedentary subjects without cardiovascular disease (18 men; 14 women; mean age 48.5 ± 14 years...

  12. The impact of automation on workload and dispensing errors in a hospital pharmacy.

    Science.gov (United States)

    James, K Lynette; Barlow, Dave; Bithell, Anne; Hiom, Sarah; Lord, Sue; Pollard, Mike; Roberts, Dave; Way, Cheryl; Whittlesea, Cate

    2013-04-01

    To determine the effect of installing an original-pack automated dispensing system (ADS) on dispensary workload and prevented dispensing incidents in a hospital pharmacy. Data on dispensary workload and prevented dispensing incidents, defined as dispensing errors detected and reported before medication had left the pharmacy, were collected over 6 weeks at a National Health Service hospital in Wales before and after the installation of an ADS. Workload was measured by non-participant observation using the event recording technique. Prevented dispensing incidents were self-reported by pharmacy staff on standardised forms. Median workloads (measured as items dispensed/person/hour) were compared using Mann-Whitney U tests and rate of prevented dispensing incidents were compared using Chi-square test. Spearman's rank correlation was used to examine the association between workload and prevented dispensing incidents. A P value of ≤0.05 was considered statistically significant. Median dispensary workload was significantly lower pre-automation (9.20 items/person/h) compared to post-automation (13.17 items/person/h, P automation (0.28%) than pre-automation (0.64%, P automation (ρ = 0.23, P automation improves dispensing efficiency and reduces the rate of prevented dispensing incidents. It is proposed that prevented dispensing incidents frequently occurred during periods of high workload due to involuntary automaticity. Prevented dispensing incidents occurring after a busy period were attributed to staff experiencing fatigue after-effects. © 2012 The Authors. IJPP © 2012 Royal Pharmaceutical Society.

  13. Service and Education: The Association Between Workload, Patient Complexity, and Teaching on Internal Medicine Inpatient Services.

    Science.gov (United States)

    Ratcliffe, Temple A; Crabtree, Meghan A; Palmer, Raymond F; Pugh, Jacqueline A; Lanham, Holly J; Leykum, Luci K

    2018-02-01

    Attending rounds remain the primary venue for formal teaching and learning at academic medical centers. Little is known about the effect of increasing clinical demands on teaching during attending rounds. To explore the relationships among teaching time, teaching topics, clinical workload, and patient complexity variables. Observational study of medicine teaching teams from September 2008 through August 2014. Teams at two large teaching hospitals associated with a single medical school were observed for periods of 2 to 4 weeks. Twelve medicine teaching teams consisting of one attending, one second- or third-year resident, two to three interns, and two to three medical students. The study examined relationships between patient complexity (comorbidities, complications) and clinical workload variables (census, turnover) with educational measures. Teams were clustered based on clinical workload and patient complexity. Educational measures of interest were time spent teaching and number of teaching topics. Data were analyzed both at the daily observation level and across a given patient's admission. We observed 12 teams, 1994 discussions (approximately 373 h of rounds) of 563 patients over 244 observation days. Teams clustered into three groups: low patient complexity/high clinical workload, average patient complexity/low clinical workload, and high patient complexity/high clinical workload. Modest associations for team, patient complexity, and clinical workload variables were noted with total time spent teaching (9.1% of the variance in time spent teaching during a patient's admission; F[8,549] = 6.90, p complexity characteristics among teams were only modestly associated with total teaching time and teaching topics.

  14. Measurement of Drug Craving in Persian Speaking Subjects; a Review on Current Experiences and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Masoomeh Maarefvand

    2012-09-01

    Full Text Available Background: Drug craving is considered as one of the main cores of drug dependency and addiction. Multidimensionality of drug craving, its cultural-bounded features and its intra individual rapidly changing nature makes it difficult to be measured. Nowadays, regarding different psychometric approaches, there are various instruments available for measurement of different aspects of drug craving but mainly for Latin-based languages in North America and European countries. High prevalence and special conditions, and unique subcultures in substance abuse and addiction in many countries, like Iran, make the design of culturally validated instruments for drug craving assessment priority. Materials and Methods: Comprehensive review on drug craving measurement instruments for Persian speaking subjects have been performed by searching in databases (ELSEVIER, Science Direct and Scientific Information Database (SID and investigating of related documents on regional experiences. Results: In this article seven main categories of drug craving instruments have been reviewed focusing on validated versions in Persian language including: self-reports, reinforcement “proxies”, drug self administration, psycho physiological responding, neurobiological responding, cognitive processing and expressive methods. Conclusion: Reviewing on weak and strength points of each instrument group and national and regional experiences shows that designing and validating a new series of ecologically-validated instruments for multidimensional measurement of drug craving in different addiction subcultures should be prioritized to cover current methodological gaps in substance abuse studies in Iran.

  15. Objective and subjective measures of the quality of managed care in nursing homes.

    Science.gov (United States)

    Schnelle, J F; Ouslander, J G; Buchanan, J; Zellman, G; Farley, D; Hirsch, S H; Reuben, D B

    1999-04-01

    The number of nursing home (NH) residents enrolled in managed care plans (HMO) will increase, and there is concern that the quality of their medical care may be compromised by cost-containment pressures. In this study, we evaluated the medical care of residents enrolled in 3 health maintenance organizations (HMO) that developed specific long-term care programs. To compare the medical care received by NH residents enrolled in HMO and Fee-for-Service (FFS) plans with both objective process of care and consumer perception (subjective) measures. To describe the relationship between the objective and subjective measures. Number of primary care visits per month; process of medical care for 2 geriatric tracer conditions (falls, fevers); family and residents' perceptions of the adequacy of sickness episode management; and the frequency of primary provider visits. Quasi-experimental. HMO residents received more timely and appropriate responses to falls and fevers than did FFS residents. HMO residents also received more frequent routine visits by a primary care provider team consisting of a physician and nurse practitioner. Consumer perceptions of quality did not differ between the HMO and FFS groups. Families within both groups were significantly more positive than were residents about the frequency of visits by both physicians and nurse practitioners. Within the HMO group, both families and residents were more positive about the frequency of nurse practitioner visits than were physician visits even when the frequency of visits by the 2 providers were similar. Although the medical care received by HMO residents was better on most objective process measures than that received by FFS residents, consumer perceptions of care did not detect those differences. NH residents and families have different perceptions about the adequacy of visits by physicians and nurse practitioners, and both families and residents appear to have different expectations concerning how often they want

  16. Internal Lymphedema Correlates with Subjective and Objective Measures of Dysphagia in Head and Neck Cancer Patients.

    Science.gov (United States)

    Jackson, Leanne K; Ridner, Sheila H; Deng, Jie; Bartow, Carmin; Mannion, Kyle; Niermann, Ken; Gilbert, Jill; Dietrich, Mary S; Cmelak, Anthony J; Murphy, Barbara A

    2016-09-01

    Tumor/treatment-related internal lymphedema (IL) and/or external lymphedema (EL) are associated with functional deficits and increased symptom burden in head and neck cancer patients (HNCP). Previously, we noted association between EL/IL and patient-reported dysphagia using the Vanderbilt Head and Neck Symptom Survey (VHNSS) version 1.0. To determine the relationship between IL/EL and subjective and objective measures of swallowing function. Eighty-one HNCP completed: (1) VHNSS version 2.0, including 13 swallowing/nutrition-related questions grouped into three clusters: swallow solids (ss), swallow liquids (sl), and nutrition(nt); (2) physical assessment of EL using Foldi scale; (3) endoscopic assessment of IL using Patterson scale (n = 56); and (4) modified barium swallow study rated by dysphagia outcome and severity scale (DOSS) and in conjunction with a swallow evaluation by National Outcomes Measurement System (NOMS). Examinations were performed at varied time points to assess lymphedema spectrum, from baseline (n = 15, 18.1%) to 18 months post-therapy (n = 20, 24.1%). VHNSS swallow/nutrition items scores correlated with NOMS/DOSS ratings (p nutrition scores correlated with maximum grade of swelling for any single structure on Patterson scale: ss (0.43; p = 0.001); sl (0.38; p = 0.004); nt (0.41; p = 0.002). IL of aryepiglottic/pharyngoepiglottic folds, epiglottis, and pyriform sinus were most strongly correlated with VHNSS and NOMS ratings. NOMS/DOSS ratings correlated with EL (> = -0.34; p nutrition items and EL ( 0.20). IL correlated with subjective and objective measures of swallow dysfunction. Longitudinal analysis of trajectory and impact of IL/EL on dysphagia is ongoing.

  17. Reasons for adopting technological innovations reducing physical workload in bricklaying.

    Science.gov (United States)

    de Jong, A M; Vink, P; de Kroon, J C A

    2003-09-15

    In this paper the adoption of technological innovations to improve the work of bricklayers and bricklayers' assistants is evaluated. Two studies were performed among 323 subjects to determine the adoption of the working methods, the perceived workload, experiences with the working methods, and the reasons for adopting the working methods. Furthermore, a comparison of the results of the studies was made with those of two similar studies in the literature. The results show that more than half of the sector adopted the innovations. The perceived workload was reduced. The employees and employers are satisfied with the working methods and important reasons for adoption were cost/benefit advantages, improvement of work and health, and increase in productivity. Problems preventing the adoption were the use of the working methods at specific sites, for instance in renovation work. The adoption of the new working methods could perhaps have been higher or faster if more attention had been paid to the active participation of bricklayers and bricklayers' assistants during the development of the new working methods and to the use of modern media techniques, such as the Internet and CD/DVD.

  18. Vocal efficiency measurements in subjects with vocal polyps and nodules: a preliminary report.

    Science.gov (United States)

    Jiang, Jack; Stern, Jennifer; Chen, Hui-Jun; Solomon, Nancy Pearl

    2004-04-01

    Vocal efficiency is a quantitative measure of the ability of the larynx to convert subglottal power to acoustic power. On the basis of the scant previous literature and clinical intuition, we tested the hypothesis that vocal efficiency, as an indicator of the functional status of the larynx, is abnormally reduced in persons with vocal nodules and polyps. Because the most difficult aspect of obtaining measures of vocal efficiency has been the determination of subglottal pressure, we applied a noninvasive airflow interruption technique for this purpose. Subjects with normal voices (n = 22), vocal polyps (n = 14), and vocal nodules (n = 16) phonated at different intensities into a mask connected by way of piping to a flow meter, a pressure transducer, and an acoustic microphone. Inflation of a balloon-type valve located within the piping provided interruption of phonation. The intraoral pressure plateau occurring during flow interruption was used to estimate subglottal pressure. Subglottal power and acoustic power were determined, and their quotient provided a measure of vocal efficiency. The vocal efficiency in the normal subjects averaged 1.15 x 10(-5) at 70 dB, 3.17 x 10(-5) at 75 dB, 7.52 x 10(-5) at 80 dB, and 1.41 x 10(-4) at 85 dB. The vocal efficiency in the patients with vocal polyps averaged 3.62 x 10(-6) at 70 dB, 8.34 x 10(-6) at 75 dB, 2.10 x 10(-5) at 80 dB, and 4.26 x 10(-5) at 85 dB. The vocal efficiency in the patients with vocal nodules averaged 4.32 x 10(-6) at 70 dB, 1.57 x 10(-5) at 75 dB, 4.26 x 10(-5) at 80 dB, and 8.34 x 10(-5) at 85 dB. As compared to the normal subjects, the patients with laryngeal polyps or vocal nodules had significantly reduced vocal efficiency. These results provide quantitative verification of the clinical impression of inefficient phonation in patients with mass lesions of the vocal folds.

  19. Generating Shifting Workloads to Benchmark Adaptability in Relational Database Systems

    Science.gov (United States)

    Rabl, Tilmann; Lang, Andreas; Hackl, Thomas; Sick, Bernhard; Kosch, Harald

    A large body of research concerns the adaptability of database systems. Many commercial systems already contain autonomic processes that adapt configurations as well as data structures and data organization. Yet there is virtually no possibility for a just measurement of the quality of such optimizations. While standard benchmarks have been developed that simulate real-world database applications very precisely, none of them considers variations in workloads produced by human factors. Today’s benchmarks test the performance of database systems by measuring peak performance on homogeneous request streams. Nevertheless, in systems with user interaction access patterns are constantly shifting. We present a benchmark that simulates a web information system with interaction of large user groups. It is based on the analysis of a real online eLearning management system with 15,000 users. The benchmark considers the temporal dependency of user interaction. Main focus is to measure the adaptability of a database management system according to shifting workloads. We will give details on our design approach that uses sophisticated pattern analysis and data mining techniques.

  20. Effect of respiratory pattern on automated clinical blood pressure measurement: an observational study with normotensive subjects.

    Science.gov (United States)

    Herakova, Natalia; Nwobodo, Nnenna Harmony Nzeribe; Wang, Ying; Chen, Fei; Zheng, Dingchang

    2017-01-01

    It has been reported that deep breathing could reduce blood pressures (BP) in general. It is also known that BP is decreased during inhalation and increased during exhalation. Therefore, the measured BPs could be potentially different during deep breathing with different lengths of inhalation and exhalation. This study aimed to quantitatively investigate the effect of different respiratory patterns on BPs. Forty healthy subjects (20 males and 20 females, aged from 18 to 60 years) were recruited. Systolic and diastolic BPs (SBP and DBP) were measured using a clinically validated automated BP device. There were two repeated measurement sessions for each subject. Within each session, eight BP measurements were performed, including 4 measurements during deep breathing with different respiratory patterns (Pattern 1: 4.5 s vs 4.5 s; Patter 2: 6 s vs 2 s; Pattern 3: 2 s vs 6 s; and Pattern 4: 1.5 s vs 1.5 s, respectively for the durations of inhalation and exhalation) and additional 4 measurements from 1 min after the four different respiratory patterns. At the beginning and end of the two repeated measurement sessions, there were two baseline BP measurements under resting condition. The key experimental results showed that overall automated SBP significantly decreased by 3.7 ± 5.7 mmHg, 3.9 ± 5.2 mmHg, 1.7 ± 5.9 mmHg and 3.3 ± 5.3 mmHg during deep breathing, respectively for Patterns 1, 2, 3 and 4 (all p Pattern 3). Similarly, the automated DBPs during deep breathing in pattern 1, 2 and 4 decreased by 3.7 ± 5.0 mmHg, 3.7 ± 4.9 mmHg and 4.6 ± 3.9 mmHg respectively (all p Pattern 3 with a decrease of 1.0 ± 4.3 mmHg, p = 0.14). Correspondingly, after deep breathing, automated BPs recovered back to normal with no significant difference in comparison with baseline BP (all p > 0.05, except for SBP in Pattern 4). In summary, this study has quantitatively demonstrated that the measured automated BPs decreased

  1. Effects of Background Music on Objective and Subjective Performance Measures in an Auditory BCI.

    Science.gov (United States)

    Zhou, Sijie; Allison, Brendan Z; Kübler, Andrea; Cichocki, Andrzej; Wang, Xingyu; Jin, Jing

    2016-01-01

    Several studies have explored brain computer interface (BCI) systems based on auditory stimuli, which could help patients with visual impairments. Usability and user satisfaction are important considerations in any BCI. Although background music can influence emotion and performance in other task environments, and many users may wish to listen to music while using a BCI, auditory, and other BCIs are typically studied without background music. Some work has explored the possibility of using polyphonic music in auditory BCI systems. However, this approach requires users with good musical skills, and has not been explored in online experiments. Our hypothesis was that an auditory BCI with background music would be preferred by subjects over a similar BCI without background music, without any difference in BCI performance. We introduce a simple paradigm (which does not require musical skill) using percussion instrument sound stimuli and background music, and evaluated it in both offline and online experiments. The result showed that subjects preferred the auditory BCI with background music. Different performance measures did not reveal any significant performance effect when comparing background music vs. no background. Since the addition of background music does not impair BCI performance but is preferred by users, auditory (and perhaps other) BCIs should consider including it. Our study also indicates that auditory BCIs can be effective even if the auditory channel is simultaneously otherwise engaged.

  2. Comparison between refraction measured by Spot Vision ScreeningTM and subjective clinical refractometry

    Directory of Open Access Journals (Sweden)

    Daniela Lima de Jesus

    2016-02-01

    Full Text Available OBJECTIVE: The purpose of this study was to evaluate the accuracy of Spot Vision ScreeningTM as an autorefractor by comparing refraction measurements to subjective clinical refractometry results in children and adult patients. METHODS: One-hundred and thirty-four eyes of 134 patients were submitted to refractometry by Spot and clinical refractometry under cycloplegia. Patients, students, physicians, staff and children of staff from the Hospital das Clínicas (School of Medicine, University of São Paulo aged 7-50 years without signs of ocular disease were examined. Only right-eye refraction data were analyzed. The findings were converted in magnitude vectors for analysis. RESULTS: The difference between Spot Vision ScreeningTM and subjective clinical refractometry expressed in spherical equivalents was +0.66±0.56 diopters (D, +0.16±0.27 D for the vector projected on the 90 axis and +0.02±0.15 D for the oblique vector. CONCLUSIONS: Despite the statistical significance of the difference between the two methods, we consider the difference non-relevant in a clinical setting, supporting the use of Spot Vision ScreeningTM as an ancillary method for estimating refraction.

  3. Comparison between refraction measured by Spot Vision Screening™ and subjective clinical refractometry.

    Science.gov (United States)

    de Jesus, Daniela Lima; Villela, Flávio Fernandes; Orlandin, Luis Fernando; Eiji, Fernando Naves; Dantas, Daniel Oliveira; Alves, Milton Ruiz

    2016-02-01

    The purpose of this study was to evaluate the accuracy of Spot Vision Screening™ as an autorefractor by comparing refraction measurements to subjective clinical refractometry results in children and adult patients. One-hundred and thirty-four eyes of 134 patients were submitted to refractometry by Spot and clinical refractometry under cycloplegia. Patients, students, physicians, staff and children of staff from the Hospital das Clínicas (School of Medicine, University of São Paulo) aged 7-50 years without signs of ocular disease were examined. Only right-eye refraction data were analyzed. The findings were converted in magnitude vectors for analysis. The difference between Spot Vision Screening™ and subjective clinical refractometry expressed in spherical equivalents was +0.66±0.56 diopters (D), +0.16±0.27 D for the vector projected on the 90 axis and +0.02±0.15 D for the oblique vector. Despite the statistical significance of the difference between the two methods, we consider the difference non-relevant in a clinical setting, supporting the use of Spot Vision Screening™ as an ancillary method for estimating refraction.

  4. Comparison between refraction measured by Spot Vision ScreeningTM and subjective clinical refractometry

    Science.gov (United States)

    de Jesus, Daniela Lima; Villela, Flávio Fernandes; Orlandin, Luis Fernando; Eiji, Fernando Naves; Dantas, Daniel Oliveira; Alves, Milton Ruiz

    2016-01-01

    OBJECTIVE: The purpose of this study was to evaluate the accuracy of Spot Vision ScreeningTM as an autorefractor by comparing refraction measurements to subjective clinical refractometry results in children and adult patients. METHODS: One-hundred and thirty-four eyes of 134 patients were submitted to refractometry by Spot and clinical refractometry under cycloplegia. Patients, students, physicians, staff and children of staff from the Hospital das Clínicas (School of Medicine, University of São Paulo) aged 7-50 years without signs of ocular disease were examined. Only right-eye refraction data were analyzed. The findings were converted in magnitude vectors for analysis. RESULTS: The difference between Spot Vision ScreeningTM and subjective clinical refractometry expressed in spherical equivalents was +0.66±0.56 diopters (D), +0.16±0.27 D for the vector projected on the 90 axis and +0.02±0.15 D for the oblique vector. CONCLUSIONS: Despite the statistical significance of the difference between the two methods, we consider the difference non-relevant in a clinical setting, supporting the use of Spot Vision ScreeningTM as an ancillary method for estimating refraction. PMID:26934234

  5. A Systematic Review on Existing Measures for the Subjective Assessment of Rehabilitation and Assistive Robot Devices

    Directory of Open Access Journals (Sweden)

    Yiannis Koumpouros

    2016-01-01

    Full Text Available The objective of the current study is to identify and classify outcome measures currently used for the assessment of rehabilitation or assistive robot devices. We conducted a systematic review of the literature using PubMed, MEDLINE, CIRRIE, and Scopus databases for studies that assessed rehabilitation or assistive robot devices from 1980 through January 2016. In all, 31 articles met all inclusion criteria. Tailor-made questionnaires were the most commonly used tool at 66.7%, while the great majority (93.9% of the studies used nonvalidated instruments. The study reveals the absence of a standard scale which makes it difficult to compare the results from different researchers. There is a great need, therefore, for a valid and reliable instrument to be available for use by the intended end users for the subjective assessment of robot devices. The study concludes by identifying two scales that have been validated in general assistive technology devices and could support the scope of subjective assessment in rehabilitation or assistive robots (however, with limited coverage and a new one called PYTHEIA, recently published. The latter intends to close the gap and help researchers and developers to evaluate, assess, and produce products that satisfy the real needs of the end users.

  6. Longitudinal measurement equivalence of subjective language brokering experiences scale in Mexican American adolescents.

    Science.gov (United States)

    Kim, Su Yeong; Hou, Yang; Shen, Yishan; Zhang, Minyu

    2017-04-01

    Language brokering occurs frequently in immigrant families and can have significant implications for the well-being of family members involved. The present study aimed to develop and validate a measure that can be used to assess multiple dimensions of subjective language brokering experiences among Mexican American adolescents. Participants were 557 adolescent language brokers (54.2% female, Mage.wave1 = 12.96, SD = .94) in Mexican American families. Using exploratory and confirmatory factor analyses, we were able to identify 7 reliable subscales of language brokering: linguistic benefits, socioemotional benefits, efficacy, positive parent-child relationships, parental dependence, negative feelings , and centrality . Tests of factorial invariance show that these subscales demonstrate, at minimum, partial strict invariance across time and across experiences of translating for mothers and fathers, and in most cases, also across adolescent gender, nativity, and translation frequency. Thus, in general, the means of the subscales and the relations among the subscales with other variables can be compared across these different occasions and groups. Tests of criterion-related validity demonstrated that these subscales correlated, concurrently and longitudinally, with parental warmth and hostility, parent-child alienation, adolescent family obligation, depressive symptoms, resilience, and life meaning. This reliable and valid subjective language brokering experiences scale will be helpful for gaining a better understanding of adolescents' language brokering experiences with their mothers and fathers, and how such experiences may influence their development. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Effects of background music on objective and subjective performance measures in an auditory BCI

    Directory of Open Access Journals (Sweden)

    Sijie Zhou

    2016-10-01

    Full Text Available Several studies have explored brain computer interface (BCI systems based on auditory stimuli, which could help patients with visual impairments. Usability and user satisfaction are important considerations in any BCI. Although background music can influence emotion and performance in other task environments, and many users may wish to listen to music while using a BCI, auditory and other BCIs are typically studied without background music. Some work has explored the possibility of using polyphonic music in auditory BCI systems. However, this approach requires users with good musical skills, and has not been explored in online experiments. Our hypothesis was that an auditory BCI with background music would be preferred by subjects over a similar BCI without background music, without any difference in BCI performance. We introduce a simple paradigm (which does not require musical skill using percussion instrument sound stimuli and background music, and evaluated it in both offline and online experiments. The result showed that subjects preferred the auditory BCI with background music. Different performance measures did not reveal any significant performance effect when comparing background music vs. no background. Since the addition of background music does not impair BCI performance but is preferred by users, auditory (and perhaps other BCIs should consider including it. Our study also indicates that auditory BCIs can be effective even if the auditory channel is simultaneously otherwise engaged.

  8. A Systematic Review on Existing Measures for the Subjective Assessment of Rehabilitation and Assistive Robot Devices.

    Science.gov (United States)

    Koumpouros, Yiannis

    2016-01-01

    The objective of the current study is to identify and classify outcome measures currently used for the assessment of rehabilitation or assistive robot devices. We conducted a systematic review of the literature using PubMed, MEDLINE, CIRRIE, and Scopus databases for studies that assessed rehabilitation or assistive robot devices from 1980 through January 2016. In all, 31 articles met all inclusion criteria. Tailor-made questionnaires were the most commonly used tool at 66.7%, while the great majority (93.9%) of the studies used nonvalidated instruments. The study reveals the absence of a standard scale which makes it difficult to compare the results from different researchers. There is a great need, therefore, for a valid and reliable instrument to be available for use by the intended end users for the subjective assessment of robot devices. The study concludes by identifying two scales that have been validated in general assistive technology devices and could support the scope of subjective assessment in rehabilitation or assistive robots (however, with limited coverage) and a new one called PYTHEIA, recently published. The latter intends to close the gap and help researchers and developers to evaluate, assess, and produce products that satisfy the real needs of the end users.

  9. Pipelines subject to slow landslide movements: Structural modeling vs field measurement

    Energy Technology Data Exchange (ETDEWEB)

    Bruschi, R.; Glavina, S.; Spinazze, M.; Tomassini, D. [Snamprogetti S.p.A., Fano (Italy); Bonanni, S.; Cuscuna, S. [Snam S.p.A., Milan (Italy)

    1996-12-01

    In recent years finite element techniques have been increasingly used to investigate the behavior of buried pipelines subject to soil movements. The use of these tools provides a rational basis for the definition of minimum wall thickness requirements in landslide crossings. Furthermore the design of mitigation measures or monitoring systems which control the development of undesirable strains in the pipe wall over time, requires a detailed structural modeling. The scope of this paper is to discuss the use of dedicated structural modeling with relevant calibration to field measurements. The strain measurements used were regularly gathered from pipe sections, in two different sites over a period of time long enough to record changes of axial strain due to soil movement. Detailed structural modeling of pipeline layout in both sites and for operating conditions, is applied. Numerical simulations show the influence of the distribution of soil movement acting on the pipeline with regards to the state of strain which can be developed in certain locations. The role of soil nature and direction of relative movements in the definition of loads transferred to the pipeline, is also discussed.

  10. Limitations of subjective cognitive load measures in simulation-based procedural training.

    Science.gov (United States)

    Naismith, Laura M; Cheung, Jeffrey J H; Ringsted, Charlotte; Cavalcanti, Rodrigo B

    2015-08-01

    The effective implementation of cognitive load theory (CLT) to optimise the instructional design of simulation-based training requires sensitive and reliable measures of cognitive load. This mixed-methods study assessed relationships between commonly used measures of total cognitive load and the extent to which these measures reflected participants' experiences of cognitive load in simulation-based procedural skills training. Two groups of medical residents (n = 38) completed three questionnaires after participating in simulation-based procedural skills training sessions: the Paas Cognitive Load Scale; the NASA Task Load Index (TLX), and a cognitive load component (CLC) questionnaire we developed to assess total cognitive load as the sum of intrinsic load (how complex the task is), extraneous load (how the task is presented) and germane load (how the learner processes the task for learning). We calculated Pearson's correlation coefficients to assess agreement among these instruments. Group interviews explored residents' perceptions about how the simulation sessions contributed to their total cognitive load. Interviews were audio-recorded, transcribed and subjected to qualitative content analysis. Total cognitive load scores differed significantly according to the instrument used to assess them. In particular, there was poor agreement between the Paas Scale and the TLX. Quantitative and qualitative findings supported intrinsic cognitive load as synonymous with mental effort (Paas Scale), mental demand (TLX) and task difficulty and complexity (CLC questionnaire). Additional qualitative themes relating to extraneous and germane cognitive loads were not reflected in any of the questionnaires. The Paas Scale, TLX and CLC questionnaire appear to be interchangeable as measures of intrinsic cognitive load, but not of total cognitive load. A more complete understanding of the sources of extraneous and germane cognitive loads in simulation-based training contexts is

  11. Estimating workload using EEG spectral power and ERPs in the n-back task

    Science.gov (United States)

    Brouwer, Anne-Marie; Hogervorst, Maarten A.; van Erp, Jan B. F.; Heffelaar, Tobias; Zimmerman, Patrick H.; Oostenveld, Robert

    2012-08-01

    Previous studies indicate that both electroencephalogram (EEG) spectral power (in particular the alpha and theta band) and event-related potentials (ERPs) (in particular the P300) can be used as a measure of mental work or memory load. We compare their ability to estimate workload level in a well-controlled task. In addition, we combine both types of measures in a single classification model to examine whether this results in higher classification accuracy than either one alone. Participants watched a sequence of visually presented letters and indicated whether or not the current letter was the same as the one (n instances) before. Workload was varied by varying n. We developed different classification models using ERP features, frequency power features or a combination (fusion). Training and testing of the models simulated an online workload estimation situation. All our ERP, power and fusion models provide classification accuracies between 80% and 90% when distinguishing between the highest and the lowest workload condition after 2 min. For 32 out of 35 participants, classification was significantly higher than chance level after 2.5 s (or one letter) as estimated by the fusion model. Differences between the models are rather small, though the fusion model performs better than the other models when only short data segments are available for estimating workload.

  12. Independent effect of physical workload and childhood socioeconomic status on low back pain among health care workers in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Marie Birk; Nabe-Nielsen, Kirsten; Clausen, Thomas

    2013-01-01

    STUDY DESIGN: Prospective cohort study. OBJECTIVE: To investigate the independent effect of physical workload and childhood socioeconomic status (CSES) on low back pain (LBP) and LBP-related sickness absence among female health care workers. SUMMARY OF BACKGROUND DATA: The role of physical workload...... on LBP independently from CSES is still subject to controversy. METHODS: We used questionnaire data from 1661 female social and health care workers responding to a questionnaire in 2004, 2005, and 2006. We collected information on CSES (parental occupation), physical workload, and LBP-prevalence (no LBP......, subchronic LBP, and frequent LBP), and LBP-related sickness absence. The participants were categorized into 5 groups according to CSES (I = highest, V = lowest). Data were analyzed using logistic regression analysis. RESULTS: Irrespective of CSES, high physical workload increased the odds ratio (OR...

  13. In situ observation and measurement of composites subjected to extremely high temperature

    Science.gov (United States)

    Fang, Xufei; Yu, Helong; Zhang, Guobing; Su, Hengqiang; Tang, Hongxiang; Feng, Xue

    2014-03-01

    In this work, we develop an instrument to study the ablation and oxidation process of materials such as C/SiC (carbon fiber reinforced silicon carbide composites) and ultra-high temperature ceramic in extremely high temperature environment. The instrument is integrated with high speed cameras with filtering lens, infrared thermometers and water vapor generator for image capture, temperature measurement, and humid atmosphere, respectively. The ablation process and thermal shock as well as the temperature on both sides of the specimen can be in situ monitored. The results show clearly the dynamic ablation and liquid oxide flowing. In addition, we develop an algorithm for the post-processing of the captured images to obtain the deformation of the specimens, in order to better understand the behavior of the specimen subjected to high temperature.

  14. Distortion-Product Otoacoustic Emission Measured Below 300 Hz in Normal-Hearing Human Subjects

    DEFF Research Database (Denmark)

    Christensen, Anders Tornvig; Ordoñez Pizarro, Rodrigo Eduardo; Hammershøi, Dorte

    2017-01-01

    Physiological noise levels in the human ear canal often exceed naturally low levels of otoacoustic emissions (OAEs) near the threshold of hearing. Low-frequency noise, and electronic filtering to cope with it, has effectively limited the study of OAE to frequencies above about 500 Hz. Presently......, a custom-built low-frequency acoustic probe was put to use in 21 normal-hearing human subjects (of 34 recruited). Distortion-product otoacoustic emission (DPOAE) was measured in the enclosed ear canal volume as the response to two simultaneously presented tones with frequencies f1 and f2. The stimulus...... known from higher frequencies. Toward low frequencies, however, the bell broadens and the optimal ratio increases proportionally to the bandwidth of an auditory filter as defined by the equivalent rectangular bandwidth. The DPOAE phase rotates monotonously as a function of the stimulus ratio, and its...

  15. Measuring the degradation level of polymer films subjected to partial discharges

    Energy Technology Data Exchange (ETDEWEB)

    Bozzo, R.; Gemme, C.; Guastavino, F. [Univ. of Genoa (Italy). Electrical Engineering Dept.; Tiemblo, P. [Inst. de Ciencia y Tecnologia de Polimeros, Madrid (Spain)

    1996-12-31

    Polymer films have been subjected to partial discharge (PD) aging. It is shown that statistical quantities derived from partial discharges patterns can be related to test conditions, film characteristics and degradation level. PDs have been measured by means of a digital system. Several resulting PD patterns have been elaborated and about 50 derived and statistical quantities have been obtained for each pattern. The effects of the test conditions on the derived quantities has been studied with relevance to the following items: To recognize the kind of film under test; to correlate the value of quantities with the degradation level of the film (i.e., to focus at the quantities which change with time); to find a link between the quantities values and the test ambient conditions (i.e., relative humidity); to determine the influence of the film thickness; and to evidence the effect of the voltage level.

  16. Workload, flow, and telepresence during teleoperation

    Energy Technology Data Exchange (ETDEWEB)

    Draper, J.V. [Oak Ridge National Lab., TN (United States); Blair, L.M. [Human Machine Interfaces, Inc., Knoxville, TN (United States)

    1996-04-01

    There is much speculation about the relations among workload, flow, telepresence, and performance during teleoperation, but few data that provide evidence concerning them. This paper presents results an investigation conducted during completion of a pipe cutting task using a teleoperator at ORNL. Results show support for the hypothesis that telepresence is related to expenditure of attentional resources, and some support for the hypothesis that telepresence is related to flow. The discussion examines the results from an attentional resources perspective on teleoperation.

  17. Cognitive Workload and Psychophysiological Parameters During Multitask Activity in Helicopter Pilots.

    Science.gov (United States)

    Gaetan, Sophie; Dousset, Erick; Marqueste, Tanguy; Bringoux, Lionel; Bourdin, Christophe; Vercher, Jean-Louis; Besson, Patricia

    2015-12-01

    Helicopter pilots are involved in a complex multitask activity, implying overuse of cognitive resources, which may result in piloting task impairment or in decision-making failure. Studies usually investigate this phenomenon in well-controlled, poorly ecological situations by focusing on the correlation between physiological values and either cognitive workload or emotional state. This study aimed at jointly exploring workload induced by a realistic simulated helicopter flight mission and emotional state, as well as physiological markers. The experiment took place in the helicopter full flight dynamic simulator. Six participants had to fly on two missions. Workload level, skin conductance, RMS-EMG, and emotional state were assessed. Joint analysis of psychological and physiological parameters associated with workload estimation revealed particular dynamics in each of three profiles. 1) Expert pilots showed a slight increase of measured physiological parameters associated with the increase in difficulty level. Workload estimates never reached the highest level and the emotional state for this profile only referred to positive emotions with low emotional intensity. 2) Non-Expert pilots showed increasing physiological values as the perceived workload increased. However, their emotional state referred to either positive or negative emotions, with a greater variability in emotional intensity. 3) Intermediate pilots were similar to Expert pilots regarding emotional states and similar to Non-Expert pilots regarding physiological patterns. Overall, high interindividual variability of these results highlight the complex link between physiological and psychological parameters with workload, and question whether physiology alone could predict a pilot's inability to make the right decision at the right time.

  18. Human vestibular memory studied via measurement of the subjective horizontal during gondola centrifugation.

    Science.gov (United States)

    Tribukait, Arne

    2003-07-01

    Measurements of the subjective visual horizontal (SVH) were made in a large swing-out gondola centrifuge. Rotation of the centrifuge was anti-clockwise, as seen from above. Test subjects were seated upright in the gondola, facing forwards. In front of the subject, at a straight-ahead eye-level position, there was a narrow luminous line, which could be rotated, by remote control, about the visual axis. At gravitoinertial force levels of 1.1-1.3G the subjects were asked to indicate, by repeatedly setting the line in darkness, what they perceived as horizontal (the SVH). During gondola centrifugation, the head and body length axis is always parallel with the resultant gravitoinertial force vector (vectorial sum of earth gravity force and the centrifugal force) i.e., the horizontal plane of the head or body does not change with respect to the gravitoinertial horizontal. Hence, the otolith organs, as well as the somatosensory system, continually signal upright position. However, the swing-out of the gondola during acceleration of the centrifuge (25 degrees at 1.1G) is a roll (frontal plane) change-in-position stimulus to the vertical semicircular canals, thus creating an otolith-semicircular canal conflict. After acceleration of the centrifuge, the SVH was initially tilted up to 20 degrees to the right relative to the gravitoinertial horizontal. Since there was no roll-tilt stimulus to gravity receptors, this SVH tilt must be related to stimulation of the semicircular canals. However, it decayed much more slowly than any known effects of angular-velocity stimulation of the semicircular canals. The decay was bi-phasic with two time constants, the smaller in the region of 1-2 min, the other being too large to be reliably estimated on the basis of data collected during only 10 min. This persistence of the SVH tilt suggests a memory for angular changes in roll head position detected by the semicircular canals-a position-storage mechanism. Further, the SVH seems to be

  19. Controls in quality assessment in gynecologic cytology: A rational approach to workload limits for the ThinPrep imaging system.

    Science.gov (United States)

    Renshaw, Andrew A; Elsheikh, Tarik M

    2010-10-01

    Major components of good quality assurance (QA) in cytology laboratories are measuring the screening accuracy of cytotechnologists (CTs) and determining appropriate workload limits for them. Currently, the FDA approved workload limits for image assisted Paps, however, are too high. In addition, the CLIA 88 mandated QA measures, by themselves, are insufficient to accurately measure the screening performance of CTs. Although the use of "controls" is fundamental to good practice in the clinical laboratory; this has not been emphasized in gynecologic cytology. In this review, we underscore the importance of using controls, such as monitoring morning and afternoon abnormal rates, in assessing CT performance and assigning reasonable workload limits. Using controls, however, requires significant alteration in the laboratory workflow, and much lower and variable workload limits for CTs, compared to those approved by FDA. © 2010 Wiley-Liss, Inc.

  20. Impact of promoting self-care in nursing workload.

    Science.gov (United States)

    Trettene, Armando Dos Santos; Fontes, Cassiana Mendes Bertoncelo; Razera, Ana Paula Ribeiro; Gomide, Marcia Ribeiro

    2016-01-01

    To assess the impact of promoting self-care in nursing workload and associate it to the variables: age, gender, socioeconomic status, education, marital status and number of children of caregivers. Prospective study with 31 children and their caregivers. Participants were assessed at two moments, 1st and 2nd hospitalization, the nursing workload was measured by the Nursing Activities Score (NAS). The mean NAS in the 1st hospitalization was 60.9% and in the 2nd hospitalization was 41.6%, that is, 14.6 and 9.9 hours of nursing, respectively. The nursing workload on the first day of hospitalization was higher compared to the last day, both for the 1st (pautocuidado na carga de trabalho de enfermagem e associá-la às variáveis: idade, gênero, classificação socioeconômica, escolaridade, estado civil e número de filhos dos cuidadores. Estudo prospectivo, onde participaram 31 crianças e seus respectivos cuidadores. Os participantes foram avaliados em dois momentos, 1ª e 2ª internação, quanto à carga de trabalho de enfermagem mensurada por meio do Nursing Activities Score (NAS). A média NAS na 1ª internação foi de 60,9%, e na 2ª internação foi de 41,6%, ou seja, 14,6 e 9,9 horas de enfermagem, respectivamente. A carga de trabalho de enfermagem no primeiro dia de internação foi maior quando comparada ao último dia, tanto na 1ª (pautocuidado a influenciaram (pautocuidado correspondeu a 14,6 horas e foi superior ao determinado pela legislação existente.

  1. Temporal and Physiologic Measurements of Deglutition in the Upright and Supine Position with Videofluoroscopy (VFS) in Healthy Subjects.

    Science.gov (United States)

    Su, H K; Khorsandi, A; Silberzweig, J; Kobren, A J; Urken, M L; Amin, M R; Branski, R C; Lazarus, C L

    2015-08-01

    Cross-sectional imaging has long been employed to examine swallowing in both the sagittal and axial planes. However, data regarding temporal swallow measures in the upright and supine positions are sparse, and none have employed the MBS impairment profile (MBSImP). We report temporal swallow measures, physiologic variables, and swallow safety of upright and supine swallowing in healthy subjects using videofluoroscopy (VFS). Twenty healthy subjects ages 21-40 underwent VFS study upright and supine. Subjects were viewed in the sagittal plane and swallowed 5 mL liquid and pudding barium. Oral transit time, pharyngeal delay time, pharyngeal response time, pharyngeal transit time, and total swallow duration were measured. Penetration/aspiration scores and 14 MBSImP variables were analyzed in both positions. All subjects completed swallows supine, although one aspirated on one liquid bolus. Temporal measures of swallowing were similar for pudding upright and supine. Pharyngeal phase swallow measures were longer for liquids in supine. MBSImP physiologic measures revealed a pharyngeal delay in both positions. Although Pen/Asp range was higher supine, more subjects penetrated upright. Temporal measures were increased for liquids in supine. Although Pen/Asp range was higher in supine, more subjects penetrated upright. These results provide support for cross-sectional supine imaging of swallowing for pudding, but perhaps not thin liquids for dysphagic patients. Slightly thicker liquids might prove reliable in supine without compromising swallow safety. Future research should examine swallow physiology in both positions in dysphagic and older healthy subjects.

  2. Use of memory strategies among younger and older adults: Results from objective and subjective measures

    Directory of Open Access Journals (Sweden)

    Aline Teixeira Fabricio

    Full Text Available Abstract Memory plays a fundamental role in the identity of people and in human life, as it enables us to interpret our surroundings and make decisions. It is known that the aging process can be accompanied by cognitive decline in some memory sub systems. However, the use of memory strategies can help encoding and retrieval of new information. Objective: The aim of this study was to identify and compare, using objective and subjective measures, which recall strategies are used spontaneously by young and older adults. Methods: Twenty-six first-year college students, and thirty-three seniors enrolled at the Third Age University of the same campus, completed a visual memory test including 18 black and white pictures, memorized a short story, and completed an open question about memory strategies, a memory check list to indicate strategies used, and a memory self-efficacy scale. The Bousfield categorization measure was also calculated from the recall protocol. Results: Young adults demonstrated better performance than the older adults on the memory tasks, and were also more confident. Both groups reported using similar strategies. Conclusion: Young and older adults seem to tackle memory tasks in similar ways but young adults outperform seniors.

  3. Relationship between Voice Complaints and Subjective and Objective Measures of Vocal Function in Iranian Female Teachers.

    Science.gov (United States)

    Faham, Maryam; Jalilevand, Nahid; Torabinezhad, Farhad; Silverman, Erin Pearson; Ahmadi, Akram; Anaraki, Zahra Ghayoumi; Jafari, Narges

    2017-07-01

    Teachers are at high risk of developing voice problems because of the excessive vocal demands necessitated by their profession. Teachers' self-assessment of vocal complaints, combined with subjective and objective measures of voice, may enable better therapeutic decision-making. This investigation compared audio-perceptual assessment and acoustic variables in teachers with and without voice complaints. Ninety-nine teachers completed this cross-sectional study and were assigned to one of two groups: those "with voice complaint (VC)" and those "without voice complaint (W-VC)." Voice samples were collected during reading, counting, and vowel prolongation tasks. Teachers were also asked to document any voice symptoms they experienced. Voice samples were analyzed using Dr. Speech program (4th version; Tiger Ltd., USA), and labeled "normal" or "abnormal" according to the "grade" dimension "G" from GRBAS scale. Twenty-one teachers were assigned to the VC group based on self-assessment data. There were statistically significant differences between the two groups with regard to self-reported voice symptoms of hoarseness, breathiness, pitch breaks, and vocal fatigue (P Teachers with and without voice complaints differed in the incidence, but not type of voice symptoms. Teachers' voice complaints did not correspond to perceptual and acoustic measures. This suggests a potential unmet need for teachers to receive further education on voice disorders. Copyright © 2017 The Voice Foundation. All rights reserved.

  4. Impedance measures in analysis and characterization of multistable structures subjected to harmonic excitation

    Science.gov (United States)

    Harne, Ryan L.; Goodpaster, Benjamin A.

    2018-01-01

    Structural components susceptible to adverse, post-buckled dynamic behaviors have long challenged the success of applications requiring lightweight, slender curved structures, while researchers have begun to leverage such bistable systems in emerging applications for novel energy attenuation and shape-changing properties. To expedite development and deployment of these built-up platforms containing post-buckled constituents, efficient approaches are required to complement time-consuming full-field models in the prediction of the near- and far-from-equilibrium dynamics. This research meets the need by introducing a semi-analytical model framework to enable the characterization of steady-state responses in multi degree-of-freedom (DOF) and multistable structural systems subjected to harmonic excitation. In so doing, the pathway for assessing impedance measures is created here so as to identify how energy travels and returns within built-up multistable structures. Verified by simulations and qualitatively validated by experiments, the analysis is shown to accurately reproduce both near- and far-from-equilibrium responses including different classes of energetic snap-through dynamics that only exist in such multistable structures. A first look at the impedance measures of different dynamic regimes reveals a connection between damping in multistable structures and the sustainability of far-from-equilibrium oscillations.

  5. Normative data of cortical excitability measurements obtained by transcranial magnetic stimulation in healthy subjects.

    Science.gov (United States)

    Cueva, Ana Sofia; Galhardoni, Ricardo; Cury, Rubens Gisbert; Parravano, Daniella Cardoso; Correa, Guilherme; Araujo, Haniel; Cecilio, Sofia Barros; Raicher, Irina; Toledo, Diego; Silva, Valquíria; Marcolin, Marco Antonio; Teixeira, Manoel Jacobsen; Ciampi de Andrade, Daniel

    2016-02-01

    The assessment of cortical excitability (CE) measurements has been increasingly used in neuropsychiatric research. However, there is scant information on the normative values of these measurements, as well as the possible effect of hemisphere laterality, gender and age on these variables. To obtain normative data for CE measurements by transcranial magnetic stimulation, to assess inter-/intra-investigator variability and the influence of sex, age and oral contraception use. A sample of 216 healthy volunteers matched according to age and gender was evaluated. Bilateral rest motor thresholds, motor evoked potentials (MEP), intracortical inhibition and facilitation were measured in the first dorsal interosseous muscle area representation of the primary motor cortex with a circular transcranial magnetic stimulation coil delivering biphasic pulses. Normative data were obtained for 200 participants (in a 1:1 male:female ratio) in a balanced proportion between five age groups (18-30; 31-40; 41-50; 51-60; >60 years). Inter/intra-investigator variability was assessed in 20 healthy volunteers in two sessions performed within a 30-minute interval. Measurements were also performed in a subgroup of 16 healthy female volunteers, using oral contraception and during the menstrual phase. Age had a dichotomous effect on CE measurements, providing significantly different normative data for subjects 50 years old, with smaller MEP's and intracortical inhibition in older individuals. There were no differences between genders or between left and right hemispheres. Also, CE parameters did not significantly differ with use of contraceptive treatment compared to the menstrual phase of the cycle. The inter-/intra-investigator reliability assessment showed some variability that may not be clinically significant. Age had a non-linear effect on CE. There were non-significant differences between genders, hemispheres or with use of oral contraceptives. There was good inter

  6. Across-subject calibration of an instrumented glove to measure hand movement for clinical purposes.

    Science.gov (United States)

    Gracia-Ibáñez, Verónica; Vergara, Margarita; Buffi, James H; Murray, Wendy M; Sancho-Bru, Joaquín L

    2017-05-01

    Motion capture of all degrees of freedom of the hand collected during performance of daily living activities remains challenging. Instrumented gloves are an attractive option because of their higher ease of use. However, subject-specific calibration of gloves is lengthy and has limitations for individuals with disabilities. Here, a calibration procedure is presented, consisting in the recording of just a simple hand position so as to allow capture of the kinematics of 16 hand joints during daily life activities even in case of severe injured hands. 'across-subject gains' were obtained by averaging the gains obtained from a detailed subject-specific calibration involving 44 registrations that was repeated three times on multiple days to 6 subjects. In additional 4 subjects, joint angles that resulted from applying the 'across-subject calibration' or the subject-specific calibration were compared. Global errors associated with the 'across-subject calibration' relative to the detailed, subject-specific protocol were small (bias: 0.49°; precision: 4.45°) and comparable to those that resulted from repeating the detailed protocol with the same subject on multiple days (0.36°; 3.50°). Furthermore, in one subject, performance of the 'across-subject calibration' was directly compared to another fast calibration method, expressed relative to a videogrammetric protocol as a gold-standard, yielding better results.

  7. The evaluation of team lifting on physical work demands and workload in ironworkers.

    Science.gov (United States)

    van der Molen, Henk F; Visser, Steven; Kuijer, P Paul F M; Faber, Gert; Hoozemans, Marco J M; van Dieën, Jaap H; Frings-Dresen, Monique H W

    2012-01-01

    Lifting and carrying heavy loads occur frequently among ironworkers and result in high prevalence and incidence rates of low back complaints, injuries and work-disability. From a health perspective, little information is available on the effect of team lifting on work demands and workload. Therefore, the objective of this study was to compare the effects of team lifting of maximally 50 kg by two ironworkers (T50) with team lifting of maximally 100 kg by four ironworkers (T100). This study combined a field and laboratory study with the following outcome measures: duration and frequency of tasks and activities, energetic workload, perceived discomfort and maximal compression forces (Fc peak) on the low back. The physical work demands and workload of an individual iron worker during manual handling of rebar materials of 100 kg with four workers did not differ from the manual handling of rebar materials of 50 kg with two workers, with the exception of low back discomfort and Fc peak. The biomechanical workload of the low back exceeded for both T50 and T100 the NIOSH threshold limit of 3400N. Therefore, mechanical transport or other effective design solutions should be considered to reduce the biomechanical workload of the low back and the accompanying health risks among iron workers.

  8. Decreasing workload among community health workers using interactive, structured, rich-media guidelines on smartphones.

    Science.gov (United States)

    Iyengar, M Sriram; Florez-Arango, Jose F

    2013-01-01

    Currently, in developing countries, there is considerable interest in using mobile phones as job-aids for community health workers (CHWs) to improve the care they provide. However, acceptance of new technologies can be inhibited if the workload imposed is perceived as excessive compared to existing methods. To compare perceived workload of CHWs using clinical care guidelines presented on mobile phones versus using conventional paper-based guidelines. Validated clinical practice guidelines were developed as Interactive Structured Rich-Medical guidelines (ISRMGs) on Windows Mobile 6.5 mobile phones. A prospective randomized controlled study was performed in Colombia in which 50 CHWs used the ISRMGs, and paper-based materials with the same information, in a cross-over design to diagnose and treat 15 matched pairs of medical cases presented on Human Patient simulators. The NASA Task Load Index, a validated measure of perceived workload, was administered and results compared by means of a mixed model analysis. When using the ISRMGs on mobile phones the health workers reported statistically significant decreases in mental demand, frustration, and overall workload as compared to using paper-based job-aids. Use of ISRMGs on mobile phones by community health workers in developing countries has the potential to decrease their perceived workload, fatigue, and enhance their ability to provide better care for more patients.

  9. Subjective Sleep Complaints in Pediatric Depression: A Controlled Study and Comparison with EEG Measures of Sleep and Waking

    Science.gov (United States)

    Bertocci, Michele A.; Dahl, Ronald E.; Williamson, Douglas E.; Iosif, Ana-Maria; Birmaher, Boris; Axelson, David; Ryan, Neal D.

    2005-01-01

    Objective: Children with major depressive disorder (MDD) often complain of sleep disturbances; however, polysomnographic studies have failed to find objective evidence of these disturbances. This article examines subjective sleep reports of children with MDD and healthy controls focusing on comparing subjective and objective sleep measures.…

  10. [Objective and subjective measures of sleep of shift-working nurses].

    Science.gov (United States)

    Matsumoto, Mitsuhiro; Lee, Bumsuk; Tozato, Fusae; Gennai, Kazuko; Shiihara, Yasufumi

    2014-01-01

    To objectively evaluate sleep quality of shift-working nurses, we used an Actiwatch 2, a watch-like actigraphy device designed to measure sleep and wakefulness based on the amount of movement. Subjective sleep quality was also assessed using the St. Mary's Hospital Sleep Questionnaire. Nineteen shift-working nurses wore the Actiwatch 2 for 5 days. The monitoring began with 2 days of the morning shift, which were followed by a 16-hour night shift and a rest day. Sleep recordings were obtained four times: night sleep after the second morning shift ("sleep 1"), napping on the night shift ("nap 1"), daytime napping after the night shift ("nap 2") and night sleep after the night shift ("sleep 2"). Actiwatch 2 sleep measures include sleep onset latency, snooze time, sleep efficiency, and percent sleep. In addition, the perceived quality of sleep was obtained using five questions of the St. Mary's Hospital Sleep Questionnaire. Objective and subjective sleep quality were compared between different sleep/nap times: sleep 1 vs. sleep 2, and nap 1 vs. nap 2. Percent sleep of sleep 2 was higher than that of sleep 1. In almost all responses to the St. Mary's Hospital Sleep Questionnaire, the perceived quality of sleep on sleep 2 was better than those of sleep 1, and that of nap 2 was better than nap 1. A significant negative correlation was found between the perceived sleep quality of nap 2 and the characteristics of participants (age, number of children, and length of career). There were positive correlations between the perceived sleep quality of sleep and percent sleep, and between the perceived sleep quality of nap and sleep efficiency. Moreover, the perceived sleep quality of nap 2 tended to decrease in participants whose bedtime deviated from the mean value on morning shift days and the rest day. We found that perceived sleep quality is related to percent sleep, and that the perceived sleep quality of nap is related to sleep efficiency. The results suggest that improving

  11. Relative workload determines exercise-induced increases in PGC-1alpha mRNA

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Lundby, Carsten; Leick, Lotte

    2010-01-01

    INTRODUCTION:: The hypothesis that brief intermittent exercise induced increases in human skeletal muscle metabolic mRNA is dependent on relative workload was investigated. METHODS:: Trained (n=10) and untrained (n=8) subjects performed exhaustive intermittent cycling exercise (4x4 min @ 85% of VO2...... peak, interspersed by 3 min). Trained subjects also performed the intermittent exercise at the same absolute workload as untrained, corresponding to 70% of VO2 peak (n=6). RESULTS:: Exercise at 85% of VO2 peak elevated (Ptrained...... after exercise at 85% of VO2 peak. Likewise, PDK4 and HKII mRNA expression were only increased (Ptrained subjects. HIF2alpha mRNA only increased (Ptrained, with no difference between the 70% and 85% of VO2 peak...

  12. Time Spent, Workload, and Student and Faculty Perceptions in a Blended Learning Environment.

    Science.gov (United States)

    Phillips, Jennifer A; Schumacher, Christie; Arif, Sally

    2016-08-25

    Objective. To evaluate student perception and time spent on asynchronous online lectures in a blended learning environment (BLE) and to assess faculty workload and perception. Methods. Students (n=427) time spent viewing online lectures was measured in three courses. Students and faculty members completed a survey to assess perceptions of a BLE. Faculty members recorded time spent creating BLEs. Results. Total time spent in the BLE was less than the allocated time for two of the three courses by 3-15%. Students preferred online lectures for their flexibility, students' ability to apply information learned, and congruence with their learning styles. Faculty members reported the BLE facilitated higher levels of learning during class sessions but noted an increase in workload. Conclusion. A BLE increased faculty workload but was well received by students. Time spent viewing online lectures was less than what was allocated in two of the three courses.

  13. Time Spent, Workload, and Student and Faculty Perceptions in a Blended Learning Environment

    Science.gov (United States)

    Schumacher, Christie; Arif, Sally

    2016-01-01

    Objective. To evaluate student perception and time spent on asynchronous online lectures in a blended learning environment (BLE) and to assess faculty workload and perception. Methods. Students (n=427) time spent viewing online lectures was measured in three courses. Students and faculty members completed a survey to assess perceptions of a BLE. Faculty members recorded time spent creating BLEs. Results. Total time spent in the BLE was less than the allocated time for two of the three courses by 3-15%. Students preferred online lectures for their flexibility, students’ ability to apply information learned, and congruence with their learning styles. Faculty members reported the BLE facilitated higher levels of learning during class sessions but noted an increase in workload. Conclusion. A BLE increased faculty workload but was well received by students. Time spent viewing online lectures was less than what was allocated in two of the three courses. PMID:27667839

  14. Longitudinal changes in ultrasound measurements: a parallel study in subjects with genetic disorders and healthy controls.

    Science.gov (United States)

    Halaba, Zenon; Pyrkosz, Antoni; Adamczyk, Piotr; Drozdzowska, Bogna; Pluskiewicz, Wojciech

    2006-03-01

    Disturbances in skeletal status in subjects with genetic disorder may increase their fracture risk. The aim of the study was longitudinal observation of phalangeal speed of sound changes across the bone over a period of 2 y in 24 patients (14 boys and 10 girls, mean age 9.63 +/- 1.8 y.) and 24 age-matched healthy controls (14 boys and 10 girls, mean age 9.65 +/- 1.71 y.). Weight and height did not differ between patients and controls at baseline and follow-up. Patients with the following disorders were evaluated: 7 with Down syndrome, 6 nonspecific mental retardations of unknown etiology, 5 Martin-Bell syndrome and 6 with other diseases. In patients and controls, no factors potentially influencing bone metabolism (except for genetic disorder) were present. Bone status was assessed by quantitative ultrasound at hand phalanges using DBM Sonic 1200 (IGEA, Carpi, Italy), which measures amplitude-dependent speed of sound (Ad-SoS [m/s]). At baseline, Ad-SoS and Z-score were significantly lower in patients than in controls (1892 +/- 51 m/s versus 1936 +/- 43 m/s, p Z-score increased significantly in patients (1892 +/- 51 m/s to 1934 +/- 48 m/s, p Z-Score were significantly lower in patients (p Z-score weight did not differ between patients and control, and height increased more in controls (13.2 +/- 2.8 cm versus 11.4 +/- 5.9 cm, p over a period of observation. In conclusion, despite comparable improvement in measured ultrasound parameter in patients and controls observed over a study duration, the difference between them remained stable.

  15. Assessing effect of meditation on cognitive workload using EEG signals

    Science.gov (United States)

    Jadhav, Narendra; Manthalkar, Ramchandra; Joshi, Yashwant

    2017-06-01

    Recent research suggests that meditation affects the structure and function of the brain. Cognitive load can be handled in effective way by the meditators. EEG signals are used to quantify cognitive load. The research of investigating effect of meditation on cognitive workload using EEG signals in pre and post-meditation is an open problem. The subjects for this study are young healthy 11 engineering students from our institute. The focused attention meditation practice is used for this study. EEG signals are recorded at the beginning of meditation and after four weeks of regular meditation using EMOTIV device. The subjects practiced meditation daily 20 minutes for 4 weeks. The 7 level arithmetic additions of single digit (low level) to three digits with carry (high level) are presented as cognitive load. The cognitive load indices such as arousal index, performance enhancement, neural activity, load index, engagement, and alertness are evaluated in pre and post meditation. The cognitive indices are improved in post meditation data. Power Spectral Density (PSD) feature is compared between pre and post-meditation across all subjects. The result hints that the subjects were handling cognitive load without stress (ease of cognitive functioning increased for the same load) after 4 weeks of meditation.

  16. Temperature measurement and control system for transtibial prostheses: Single subject clinical evaluation.

    Science.gov (United States)

    Ghoseiri, Kamiar; Zheng, Yong Ping; Leung, Aaron K L; Rahgozar, Mehdi; Aminian, Gholamreza; Masoumi, Mehdi; Safari, Mohammad Reza

    2017-01-05

    The snug fit of a prosthetic socket over the residual limb can disturb thermal balance and put skin integrity in jeopardy by providing an unpleasant and infectious environment. The prototype of a temperature measurement and control (TM&C) system was previously introduced to resolve thermal problems related to prostheses. This study evaluates its clinical application in a setting with reversal, single subject design. The TM&C system was installed on a fabricated prosthetic socket of a man with unilateral transtibial amputation. Skin temperature of the residual limb without prosthesis at baseline and with prosthesis during rest and walking was evaluated. The thermal sense and thermal comfort of the participant were also evaluated. The results showed different skin temperature around the residual limb with a temperature decrease tendency from proximal to distal. The TM&C system decreased skin temperature rise after prosthesis wearing. The same situation occurred during walking, but the thermal power of the TM&C system was insufficient to overcome heat build-up in some regions of the residual limb. The participant reported no significant change of thermal sense and thermal comfort. Further investigations are warranted to examine thermography pattern of the residual limb, thermal sense, and thermal comfort in people with amputation.

  17. Measuring Numeracy in a Community College Context: Assessing the Reliability of the Subjective Numeracy Scale

    Directory of Open Access Journals (Sweden)

    Kate S. Wolfe

    2017-07-01

    Full Text Available In this paper, our goals were to assess the suitability of the Subjective Numeracy Scale (SNS, developed for health-care use, in a new context with predominantly minority students at a South Bronx community college and to identify any race/ ethnicity, gender, and ESL enrollment effects. The scale assesses perceptions of quantitative reasoning skills and preferences for data presentation. This scale was given to a convenience sample of students in behavioral sciences classes. Results show that the SNS scale was reliable with our sample using the full thirteen-question scale or the shorter eight-item version. Gender, race/ ethnicity, and English as a Second Language (ESL are related to perceptions of QR/QL. This study may help researchers see the SNS as a reliable instrument across samples and as a way to measure numeracy. The results of the multivariate analyses raise questions for future research about cultural differences for numerical presentation among these ethnic groups and our international student population.

  18. Thermoluminescent properties of Dy doped calcium borate based glass for dose measurement subjected to photon irradiation

    Directory of Open Access Journals (Sweden)

    Tajuddin H. A.

    2017-01-01

    Full Text Available This study presents the thermoluminescent (TL dosimetric properties of calcium borate glass with various dopant concentration of dysprosium (Dy. Calcium borate glass is a new potential material to be used in radiation measurement with absorption coefficient that is close to human bone. A series of glasses based on chemical equation xCaO-(100-x B2O3 system, x = 0.1, 0.2, 0.3, 0.4, 0.5 (0< x <100 % weight have been prepared by melt quenching method. The X-ray diffraction analysis of glass samples were carried out and the result showed a broad peak, which confirmed the amorphous nature of the glass. The 70B2O3-30CaO glass sample was found as the most stable among other glass samples studied. Present work focuses on 70B2O3-30CaO glass of (0.01-0.4 mol% Dy-doped in order to investigate the thermoluminescence (TL properties, in particular, dose-response and fading. The glass samples were irradiated to dose range of 0.5-4.0 Gy subjected to 6MV photon irradiations of LINAC Primus MLC 3339. TL response of 0.3 mol% Dy-doped 70B2O3-30CaO glass was found to produce highest response, with good linear dose- response relationship.

  19. Work-Based Social Interactions, Perceived Stress, and Workload Incongruence as Antecedents of Athletic Trainer Burnout

    Science.gov (United States)

    DeFreese, J. D.; Mihalik, Jason P.

    2016-01-01

    Context Burnout is an important psychological health concern for working professionals. Understanding how psychological stress and markers of workload contribute to athletic trainers' (ATs') perceptions of burnout is highly valuable. Both positive (social support) and negative social interactions should be considered when examining relationships among markers of ATs' health and wellbeing. Objective To examine the potential effects of social interactions on the relationships between (1) burnout and perceived stress and (2) burnout and workload incongruence in ATs. Design Cross-sectional study. Setting Participating ATs completed a computer-based survey during the fall sports season. Patients or Other Participants Responding participants were ATs randomly sampled from the National Athletic Trainers' Association membership (N = 154; men = 78, women = 76; age = 36.8 ± 9.5 years). Main Outcome Measure(s) Participants completed self-report assessments (Perceived Stress Scale, Social Support Questionnaire, Positive and Negative Social Exchanges, Maslach Burnout Inventory–Human Services Survey) via a secure e-mail link. Workload incongruence was calculated by subtracting anticipated work hours from actual current work hours (6.0 ± 9.6 hours). We used hierarchical multiple regression analyses to examine hypothesized relationships among study variables. Results Social interactions did not affect the relationships between burnout and perceived stress or workload incongruence at the global or dimensional level. However, perceived stress (β = .47, P burnout. Negative social interactions trended toward significance (β = .12, P = .055). Our findings suggest that stress perceptions and social support drive the dimensional AT burnout experience, whereas workload incongruence (emotional exhaustion) and negative social interactions (depersonalization) were linked to specific burnout dimensions. Conclusions Social interactions and markers of stress and workload should be

  20. Interactions of Subjective and Objective Measures of Fatigue Defined in the Context of Brain Control of Locomotion.

    Science.gov (United States)

    Holtzer, Roee; Yuan, Jennifer; Verghese, Joe; Mahoney, Jeannette R; Izzetoglu, Meltem; Wang, Cuiling

    2017-03-01

    Fatigue adversely impacts quality of life in old age. The relationship between subjective and objective measurements of fatigue, however, is poorly understood. We examined whether subjective fatigue moderated the expression of objective fatigue during locomotion. Associations between objective and subjective measures of fatigue were predicted to manifest only under dual-task conditions that maximized cognitive demands. Participants were 314 nondemented older adults (age = 76.8±6.7 years; % female = 56). Functional near-infrared spectroscopy was used to assess oxygenated hemoglobin (HbO2) levels during walking. A 4×14-foot Zeno electronic walkway was utilized to assess stride velocity (cm/s). Objective fatigue was operationalized as attenuation in HbO2 levels and decline in stride velocity (cm/s) during six continuous straight walks under single- (normal-walk) and dual-task (walk-while-talk) conditions. The Brief Fatigue Inventory assessed subjective fatigue. Worse subjective fatigue was associated with attenuated increase in HbO2 levels (estimate = 0.175; p .05) from normal-walk to walk-while-talk conditions. Objective fatigue did not manifest and was not associated with subjective fatigue during the course of normal-walk. Worse subjective fatigue was associated with attenuated HbO2 levels in the fourth (estimate = -0.178; p subjective and objective measurements of fatigue as defined in the context of attention-demanding locomotion.

  1. Workload-Aware Indexing of Continuously Moving Objects

    DEFF Research Database (Denmark)

    Tzoumas, Kostas; Yiu, Man Lung; Jensen, Christian Søndergaard

    2009-01-01

    indexing and achieves workload-awareness by controlling the underlying index’s filtering quality. QU-Trade safely drops index updates, increasing the overlap in the index when the workload is update-intensive, and it restores the filtering capabilities of the index when the workload becomes query-intensive......The increased deployment of sensors and data communication networks yields data management workloads with update loads that are intense, skewed, and highly bursty. Query loads resulting from location-based services are expected to exhibit similar characteristics. In such environments, index...... structures can easily become performance bottlenecks. We address the need for indexing that is adaptive to the workload characteristics, called workload-aware, in order to cover the space in between maintaining an accurate index, and having no index at all. Our proposal, QU-Trade, extends R-tree type...

  2. Individual differences in working memory capacity and workload capacity

    Directory of Open Access Journals (Sweden)

    Ju-Chi eYu

    2014-12-01

    Full Text Available We investigated the relationship between working memory capacity (WMC and workload capacity (WLC. Each participant performed an operation span (OSPAN task to measure his/her WMC and three redundant-target detection tasks to measure his/her WLC. WLC was computed non-parametrically (Experiments 1 and 2 and parametrically (Experiment 2. Both levels of analyses showed that participants high in WMC had larger WLC than those low in WMC only when redundant information came from visual and auditory modalities, suggesting that high-WMC participants had superior processing capacity in dealing with redundant visual and auditory information. This difference was eliminated when multiple processes required processing for only a single working memory subsystem in a color-shape detection task and a double-dot detection task. These results highlighted the role of executive control in integrating and binding information from the two working memory subsystems for perceptual decision making.

  3. Probe-Independent EEG Assessment of Mental Workload in Pilots

    Science.gov (United States)

    2015-05-18

    A TRIDENT SCHOLAR PROJECT REPORT NO. 437 Probe-Independent EEG Assessment of Mental Workload in Pilots by Midshipman 1/C Michael K...INDEPENDENT EEG ASSESSMENT OF MENTAL WORKLOAD IN PILOTS by Midshipman 1/C Michael K. Johnson United States Naval Academy Annapolis, Maryland...REPORT TYPE 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Probe-Independent EEG Assessment of Mental Workload in Pilots 5a. CONTRACT NUMBER

  4. Filter bank common spatial patterns in mental workload estimation.

    OpenAIRE

    Arvaneh, M.; Umilta, A.; Robertson, I.H.

    2015-01-01

    EEG-based workload estimation technology provides a real time means of assessing mental workload. Such technology can effectively enhance the performance of the human-machine interaction and the learning process. When designing workload estimation algorithms, a crucial signal processing component is the feature extraction step. Despite several studies on this field, the spatial properties of the EEG signals were mostly neglected. Since EEG inherently has a poor spacial resolution, features ex...

  5. Health impairment of system engineers working on projects with heavy workload.

    Science.gov (United States)

    Shimizui, Hayato; Ooshima, Kirika; Miki, Akiko; Matsushita, Yoshie; Hattori, Youji; Sugita, Minoru

    2011-03-01

    It has been reported that many system engineers must work hard to produce computer systems, and some of them suffer from health impairment due to their hard work. The purpose of the present cross-sectional study was to investigate the situation of impaired health status of system engineers in projects with high job strain. Countermeasures against health impairment of the subjects in the projects with high job strain in practices of occupational health fields are discussed. The study subjects were five superiors and their 35 subordinates working on computer system projects with high job strain at a large computer systems corporation in the Tokyo area. The control group was comprised of three superiors and their 18 subordinates in the same corporation. From July to November, 2006, the above were interviewed by six occupational health nurses, who evaluated their health and recorded their health evaluation scores. The problems involved in producing the computer systems were sometimes very difficult to solve, even if they spent long hours working on them. The present study detected a tendency showing that healthy superiors' subordinates were unhealthy and unhealthy superiors' subordinates were healthy in the overload projects with high job strain, while this was not detected in the control groups. A few employees whose health deteriorated were faced with very hard jobs in the overload projects. This means that heavy workloads were unevenly distributed in the overload projects among superiors, and their subordinates, and the health of a few members with heavy workloads deteriorated due to the heavy workload. In order to improve such a situation, it may be important not only to commit the necessary number of employees whose working ability is high to the section but also to even the workload in the overload project by informing all members of the project the health impairment of a few members due to heavy workload, from the viewpoint of the practice of occupational health

  6. Subjective and objective measures of adaptation and readaptation to night work on an oil rig in the North Sea.

    Science.gov (United States)

    Bjorvatn, Bjørn; Stangenes, Kristine; Oyane, Nicolas; Forberg, Knut; Lowden, Arne; Holsten, Fred; Akerstedt, Torbjørn

    2006-06-01

    To study the adaptation and readaptation processes to 1 week of night work (6:30 PM to 6:30 AM) followed by 1 week of day work (6:30 AM to 6:30 PM). Part of a randomized, placebo-controlled, crossover field study. Here, data from the placebo arm are presented. Oil rig in the North Sea. Work schedule: 2 weeks on a 12-hour shift, with the first week on the night shift and the second week on the day shift. Subjects complaining about problems with adjusting to shift work. Seventeen workers completed the study. N/A. Subjective and objective measures of sleepiness (Karolinska Sleepiness Scale and simple serial reaction time test) and sleep (diary and actigraphy). Both subjective and objective measures improved gradually during night work. The return to day work after 1 week on the night shift led to a clear increase in subjective sleepiness and worsening of sleep parameters. During the week on the day shift, sleepiness and sleep gradually improved, similar to the improvement seen during night work. The workers indicated that the day shift was worse than the night shift on some of the measures, e.g., sleep length was significantly longer during the night-shift period. This is one of few studies showing how shift workers in a real-life setting adjust to night work. Both subjective and objective sleepiness and subjective sleep improved across days. The effects were especially pronounced for the subjective data.

  7. Efficient workload classification based on ignored auditory probes: A proof of concept

    Directory of Open Access Journals (Sweden)

    Raphaëlle N. Roy

    2016-10-01

    Full Text Available Mental workload is a mental state that is currently one of the main research focuses in neuroergonomics. It can notably be estimated using measurements in electroencephalography (EEG, a method that allows for direct mental state assessment. Auditory probes can be used to elicit event-related potentials (ERPs that are modulated by workload. Although some papers do report ERP modulations due to workload using attended or ignored probes, to our knowledge there is no literature regarding effective workload classification based on ignored auditory probes. In this paper, in order to efficiently estimate workload, we advocate for the use of such ignored auditory probes in a single-stimulus paradigm and a signal processing chain that includes a spatial filtering step. The effectiveness of this approach is demonstrated on data acquired from participants that performed the Multi-Attribute Task Battery – II. They carried out this task during two ten-minute blocks. Each block corresponded to a workload condition that was pseudorandomly assigned. The easy condition consisted of two monitoring tasks performed in parallel, and the difficult one consisted of those two tasks with an additional plane driving task. Infrequent auditory probes were presented during the tasks and the participants were asked to ignore them. The EEG data were denoised and the probes’ ERPs were extracted and spatially filtered using a Canonical Correlation Analysis (CCA. Next, binary classification was performed using a Fisher LDA and a 5-fold cross-validation procedure. Our method allowed for a very high estimation performance with a classification accuracy above 80% for every participant, and minimal intrusiveness thanks to the use of a single-stimulus paradigm. Therefore, this study paves the way to the efficient use of ERPs for mental state monitoring in close to real-life settings and contributes towards the development of adaptive user interfaces.

  8. The moderating effect of control over work scheduling and overtime on the relationship between workload demands and perceived job risk.

    Science.gov (United States)

    Näswall, Katharina; Burt, Christopher D B; Pearce, Megan

    2015-01-01

    This study investigated the impact of workload demands on perceived job risk using the Job Demand-Control model as a research framework. The primary objective was to test the hypothesis that employee control over work scheduling and overtime would moderate the relationship between workload demands and perceived job risk. Ninety-six participants working in a variety of industries completed measures of workload demands, and of control over work scheduling and overtime, and a measure of perceived job risk. Workload demands predicted higher perceptions of job risk. However, the results also suggest that control over overtime moderated this relationship, where those with the combination of high workload demands and low control over overtime reported higher levels of perceived risk. The results indicate that the JDC model is applicable to safety research. The results suggest that employee control over workload demands is an important variable to consider in terms of managing workplace safety. The present study also points to important areas for future research to explore in order to further understand the connection between demands and safety.

  9. Within-subject variation in BOLD-fMRI signal changes across repeated measurements: Quantification and implications for sample size

    NARCIS (Netherlands)

    Zandbelt, B.B.; Gladwin, T.E.; Raemaekers, M.; Buuren, M. van; Neggers, S.F.W.; Kahn, R.S.; Ramsey, N.F.; Vink, M.

    2008-01-01

    Functional magnetic resonance imaging (fMRI) can be used to detect experimental effects on brain activity across measurements. The success of such studies depends on the size of the experimental effect, the reliability of the measurements, and the number of subjects. Here, we report on the stability

  10. Inter-relationships between objective and subjective measures of the residential environment among urban African American women.

    Science.gov (United States)

    Sealy-Jefferson, Shawnita; Messer, Lynne; Slaughter-Acey, Jaime; Misra, Dawn P

    2017-03-01

    The inter-relationships between objective (census based) and subjective (resident reported) measures of the residential environment is understudied in African American (AA) populations. Using data from the Life Influences on Fetal Environments Study (2009-2011; n = 1387) of AA women, we quantified the area-level variation in subjective reports of residential healthy food availability, walkability, safety, and disorder that can be accounted for with an objective neighborhood disadvantage index (NDI). Two-level generalized linear models estimated associations between objective and subjective measures of the residential environment, accounting for individual-level covariates. In unconditional models, intraclass correlation coefficients for block-group variance in subjective reports ranged from 11% (healthy food availability) to 30% (safety). Models accounting for the NDI (vs. both NDI and individual-level covariates) accounted for more variance in healthy food availability (23% vs. 8%) and social disorder (40% vs. 38%). The NDI and individual-level variables accounted for 39% and 51% of the area-level variation in walkability and safety, respectively. Associations between subjective and objective measures of the residential environment were significant and in the expected direction. Future studies on neighborhood effects on health, especially among AAs, should include a wide range of residential environment measures, including subjective, objective, and spatial contextual variables. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. An assessment of the effects of navigation maps on drivers' mental workloads.

    Science.gov (United States)

    Chao, Chin-Jung; Lin, Chia-Hsyang; Hsu, Shang-Hwa

    2014-06-01

    This study compares the mental workloads and subjective feelings of drivers navigating different road patterns using different formats of electronic and paper maps. The results show drivers experience lower mental workloads when using 2D electronic maps compared to 3D electronic maps. Significant differences in galvanic skin responses were observed for navigation map formats with different road intersection patterns. The low- and high-frequency components of heart rate variability showed significant differences between map formats for regular road intersections, but no significant differences between map formats for irregular road intersections. Statistically significant effects on subjective feelings were found between different map formats and road intersection patterns. The wider implications of the study results for the design and use of navigation map interfaces are discussed.

  12. Coffee versus Caffeine: Effects on Subjective and Behavioral Measures of Alertness

    Science.gov (United States)

    1991-04-12

    particular attention to the impulsivity subscale of the Eysenck Personality Inventory ( Eysenck & Eysenck , 1964). Impulsivity is a construct related to...and only significant in one of the experiments (Exp.3). In a similar study, Anderson & Revelle (1982) again gave subjects the Eysenck Personality...Inventory ( Eysenck & Eysenck , 1964) and divided them into high and low impulsive groups based on a median split. Baseline caffeine intake of subjects

  13. Objective-subjective disparity in cancer-related cognitive impairment: does the use of change measures help reconcile the difference?

    Science.gov (United States)

    O'Farrell, Erin; Smith, Andra; Collins, Barbara

    2017-10-01

    Studies to date have found little correlation between subjective and objective measures of cognitive function in cancer patients, making it difficult to interpret the significance of their cognitive complaints. The purpose of this study was to determine if a stronger correlation would be obtained using measures of cognitive change rather than static scores. Sixty women with early stage breast cancer underwent repeated cognitive assessment over the course of chemotherapy with a neuropsychological test battery (objective measure) and with the FACT-Cog (subjective measure). Their results were compared to 60 healthy women matched on age and education and assessed at similar intervals. We used multilevel modeling, with FACT-Cog as the dependent measure and ordinary least squares slopes of a neuropsychological summary score as the independent variable, to evaluate the co-variation between the subjective and objective measures over time RESULTS: Measures of both objective and subjective cognitive function declined over the course of chemotherapy in the breast cancer patients but there was no significant relationship between them, even when using change measures. Change in objective cognitive function was not related to change in anxiety or fatigue scores but the decline in perceived cognitive function was associated with greater anxiety and fatigue. The discrepancy in objective and subjective measures of cognition in breast cancer patients cannot be accounted for in terms of a failure to use change measures. Although the results are negative, we contend that this is the more appropriate methodology for analyzing cancer-related changes in cognition. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Patient Safety Incidents and Nursing Workload.

    Science.gov (United States)

    Carlesi, Katya Cuadros; Padilha, Kátia Grillo; Toffoletto, Maria Cecília; Henriquez-Roldán, Carlos; Juan, Monica Andrea Canales

    2017-04-06

    to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs) was performed using the Therapeutic Interventions Scoring System (TISS-28) and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919) and rate of falls (r = 0.8770). The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload. identificar a relação entre a carga de trabalho da equipe de enfermagem e a ocorrência de incidentes de segurança dos pacientes ligados aos cuidados de enfermagem de um hospital público no Chile. pesquisa transversal analítica quantitativa através de revisão de prontuários médicos. A estimativa da carga de trabalho em Unidade de Terapia Intensiva (UTI) foi realizada utilizando o Índice de Intervenções Terapêuticas-TISS-28 e para os outros serviços, foram utilizados os cocientes enfermeira/paciente e auxiliar de enfermagem/ paciente. Foram feitas análises univariada descritiva e multivariada. Para a análise multivariada utilizou-se análise de componentes principais e correlação de Pearson. foram analisados 879 prontuáriosclínicos de pós-alta e a carga de trabalho de 85 enfermeiros e 157

  15. Do Subjective Measures Improve the Ability to Identify Limited Health Literacy in a Clinical Setting?

    Science.gov (United States)

    Goodman, Melody S; Griffey, Richard T; Carpenter, Christopher R; Blanchard, Melvin; Kaphingst, Kimberly A

    2015-01-01

    Existing health literacy assessments developed for research purposes have constraints that limit their utility for clinical practice, including time requirements and administration protocols. The Brief Health Literacy Screen (BHLS) consists of 3 self-administered Single-Item Literacy Screener (SILS) questions and obviates these clinical barriers. We assessed whether the addition of SILS items or the BHLS to patient demographics readily available in ambulatory clinical settings reaching underserved patients improves the ability to identify limited health literacy. We analyzed data from 2 cross-sectional convenience samples of patients from an urban academic emergency department (n = 425) and a primary care clinic (n = 486) in St. Louis, Missouri. Across samples, health literacy was assessed using the Rapid Estimate of Adult Literacy in Medicine-Revised (REALM-R), Newest Vital Sign (NVS), and the BHLS. Our analytic sample consisted of 911 adult patients, who were primarily female (62%), black (66%), and had at least a high school education (82%); 456 were randomly assigned to the estimation sample and 455 to the validation sample. The analysis showed that the best REALM-R estimation model contained age, sex, education, race, and 1 SILS item (difficulty understanding written information). In validation analysis this model had a sensitivity of 62%, specificity of 81%, a positive likelihood ratio (LR(+)) of 3.26, and a negative likelihood ratio (LR(-)) of 0.47; there was a 28% misclassification rate. The best NVS estimation model contained the BHLS, age, sex, education and race; this model had a sensitivity of 77%, specificity of 72%, LR(+) of 2.75, LR(-) of 0.32, and a misclassification rate of 25%. Findings suggest that the BHLS and SILS items improve the ability to identify patients with limited health literacy compared with demographic predictors alone. However, despite being easier to administer in clinical settings, subjective estimates of health literacy have

  16. Objective Versus Subjective Measures of Executive Functions: Predictors of Participation and Quality of Life in Parkinson Disease?

    Science.gov (United States)

    Vlagsma, Thialda T; Koerts, Janneke; Tucha, Oliver; Dijkstra, Hilde T; Duits, Annelien A; van Laar, Teus; Spikman, Jacoba M

    2017-11-01

    To determine whether objective (neuropsychological tests) and subjective measures (questionnaires) of executive functions (EFs) are associated in patients with Parkinson disease (PD), and to determine to what extent level of participation and quality of life (QoL) of patients with PD can be predicted by these measures of EFs. Correlational research design (case-control and prediction design). Departments of neuropsychology of 3 medical centers. A sample (N=136) of patients with PD (n=42) and their relatives, and controls without PD (n=94). Not applicable. A test battery measuring EFs. In addition, patients, their relatives, and controls completed the Dysexecutive Questionnaire, Brock Adaptive Functioning Questionnaire, and Barkley Deficits in Executive Functioning Scale - time management questionnaires measuring complaints about EFs. Participation and QoL were measured with the Impact on Participation and Autonomy scale and the Parkinson's Disease Questionnaire-39, respectively. Patients with PD showed impairments in EFs on objective tests and reported significantly more complaints about EFs than did controls without PD. No associations were found between patients' performances on objective and subjective measures of EFs. However, both objective and subjective measures predicted patients' level of participation. In addition, subjective measures of EFs predicted QoL in patients with PD. These findings show that objective and subjective measures of EFs are not interchangeable and that both approaches predict level of participation and QoL in patients with PD. However, within this context, sex needs to be taken into account. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  17. Energy cost of walking measurements in subjects with lower limb amputations: a comparison study between floor and treadmill test.

    Science.gov (United States)

    Traballesi, Marco; Porcacchia, Paolo; Averna, Tiziano; Brunelli, Stefano

    2008-01-01

    Measuring the energy cost of walking (ECW) is a valid way of assessing the walking efficiency of subjects who were prosthetic users following lower limb amputation. The aim of this study was to determine whether, in these subjects, treadmill and floor ECW measurements are comparable. We tested 24 subjects who had undergone unilateral lower limb amputations for vascular diseases as they walked at a self-selected comfortable speed on the floor and on a treadmill. The tests were conducted at the end of rehabilitative treatment to fit prosthesis. Eight subjects underwent transtibial and 16 transfemoral amputation. The measurements were taken with a portable gas analyzer. The self-selected comfortable speed on the treadmill was significantly lower than that on the floor, where the patients adopted the aid they normally used for walking; oxygen consumption was the same in the two tests. Therefore, for both transtibial and transfemoral patients, ECW was greater during walking on the treadmill. Steady-state heart rate did not differ in the two tests. The data show that the ECW values of the amputated subjects obtained on the treadmill at the end of rehabilitation did not correspond with those they obtained on the floor. The floor test is the one that may better reflect walking with prostheses and aids in everyday life, in subjects with dysvascular lower limb amputation, using the prosthesis for a short time.

  18. The stress and workload of virtual reality training: the effects of presence, immersion and flow.

    Science.gov (United States)

    Lackey, S J; Salcedo, J N; Szalma, J L; Hancock, P A

    2016-08-01

    The present investigation evaluated the effects of virtual reality (VR) training on the performance, perceived workload and stress response to a live training exercise in a sample of Soldiers. We also examined the relationship between the perceptions of that same VR as measured by engagement, immersion, presence, flow, perceived utility and ease of use with the performance, workload and stress reported on the live training task. To a degree, these latter relationships were moderated by task performance, as measured by binary (Go/No-Go) ratings. Participants who reported positive VR experiences also tended to experience lower stress and lower workload when performing the live version of the task. Thus, VR training regimens may be efficacious for mitigating the stress and workload associated with criterion tasks, thereby reducing the ultimate likelihood of real-world performance failure. Practitioner Summary: VR provides opportunities for training in artificial worlds comprised of highly realistic features. Our virtual room clearing scenario facilitated the integration of Training and Readiness objectives and satisfied training doctrine obligations in a compelling engaging experience for both novice and experienced trainees.

  19. Ontario protocol assessment level: clinical trial complexity rating tool for workload planning in oncology clinical trials.

    Science.gov (United States)

    Smuck, Bobbi; Bettello, Phyllis; Berghout, Koralee; Hanna, Tracie; Kowaleski, Brenda; Phippard, Lynda; Au, Diana; Friel, Kay

    2011-03-01

    The Ontario Institute for Cancer Research supported the creation of a working group with the objective of developing a standard rating scale to evaluate clinical trial complexity and applying the scale to facilitate workload measurement for Ontario cancer research sites. The lack of a mechanism to measure the workload involved in a clinical trials protocol was identified and confirmed by a literature review. To collect information on how Ontario sites were assessing workload, a survey was distributed and evaluated. As a result, the working group developed the Ontario Protocol Assessment Level (OPAL), a protocol complexity rating scale designed to capture the workload involved in a clinical trial. After a training workshop on the application, OPAL was evaluated by 17 Ontario cancer centers to demonstrate its reliability and consistency during a 3-month pilot study. Twenty-seven protocols were reviewed by multiple sites, and the majority of the sites reported OPAL score differences between 0 and 1.5. OPAL provides clinical trials departments with an objective method of quantifying clinical trials activity on the basis of study protocol complexity. With consistent application of OPAL, sites can manage staffing objectively. The working group is continuing to monitor the application of OPAL in Ontario.

  20. Evaluation of Subjective Measurement Systems with Focus on Workmanship Scratches and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Fitzgerald, Jesse

    2011-02-24

    The presence of workmanship defects at the Kansas City Plant (KCP) is not a new problem nor is it an easy one to remedy. The lack of well defined parameters, subjective evaluations, and operator dependency makes this problem difficult to analyze. At the time of project assignment, workmanship defects comprised approximately 50% of all non-conformance reports for internally produced products. Not all of these non-conformances result in product rejections, thus inferring that inconsistency in evaluations were present. The purpose of this study was to identify a method for evaluating an operator’s ability to properly characterize subjective defects. Since the scope of the project was limited to no funding, scratch depth was selected as the only criteria to evaluate. It was determined that the introduction of a reference standard coupled with a predefined gate-sorting technique approved by the customer can statistically improve an operators ability to perform subjective evaluations.

  1. Estimating mental workload through event-related fluctuations of pupil area during a task in a virtual world.

    Science.gov (United States)

    Reiner, Miriam; Gelfeld, Tatiana M

    2014-07-01

    Monitoring mental load for optimal performance has become increasingly central with the recently evolving need to cope with exponentially increasing amounts of data. This paper describes a non-intrusive, objective method to estimate mental workload in an immersive virtual reality system, through analysis of frequencies of pupil fluctuations. We tested changes in mental workload with a number of task-repetitions, level of predictability of the task and the effect of prior experience in predictable task performance, on mental workload of unpredictable task performance. Two measures were used to calculate mental workload: the ratio of Low Frequency to High Frequency components of pupil fluctuations, and the High Frequency alone, all extracted from the Power Spectrum Density of pupil fluctuations. Results show that mental workload decreases with a number of repetitions, creating a mode in which the brain acts as an automatic controller. Automaticity during training occurs only after a minimal number of repetitions, which once achieved, resulted in further improvements in the performance of unpredictable motor tasks, following training in a predictable task. These results indicate that automaticity is a central component in the transfer of skills from highly predictable to low predictable motor tasks. Our results suggest a potentially applicable method to brain-computer-interface systems that adapt to human mental workload, and provide intelligent automated support for enhanced performance. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Predicting screening sensitivity from workload in gynecologic cytology: a review.

    Science.gov (United States)

    Renshaw, Andrew A; Elsheikh, Tarik M

    2011-11-01

    Recent studies have shown that it is possible to correlate workload or epithelial cell abnormality (ECA) adjusted workload with screening sensitivity. The results show that for manual screening of conventional smears or SurePath slides, screening sensitivity begins to fall with workloads as low as 30 slides/day. For review of slides with the ThinPrep Imaging System, screening sensitivity appears to be better correlated with ECA adjusted workload (workload × ECA rate) than workload alone. Screening sensitivity with the ThinPrep imager appears to fall at ECA adjusted workloads of 7 slides/day at a threshold of ASCUS and above and LSIL, and slightly lower for HSIL. This corresponds to 70 slides/day at an ECA rate of 10%. The variance in these models is likely high reflecting a wide range of individual cytotechnologist performance. Strategies to most effectively incorporate this data in the management of workload in the laboratory are reviewed. Copyright © 2010 Wiley-Liss, Inc.

  3. Effects of motorway lighting on workload and driving behaviour

    NARCIS (Netherlands)

    Hogema, J.H.; Veltman, J.A.; Hof, A. van 't

    2004-01-01

    The Dutch Ministry of Transport, Public Works and Water Management needs knowledge in the area of workload in car driving. This paper describes a study in which the effects of traffic volume, road lighting, and a cognitively loading secondary task on driving behaviour and workload were investigated.

  4. Effects of motorway lighting on workload and driving behaviour

    NARCIS (Netherlands)

    Hogema, J.H.; Veltman, J.A.; Hof, A. van 't

    2005-01-01

    The Dutch Ministry of Transport, Public Works and Water Management needs knowledge in the area of workload in car driving. This paper describes a study in which the effects of traffic volume, road lighting, and a cognitively loading secondary task on driving behaviour and workload were investigated.

  5. The influence of shop characteristics on workload control

    NARCIS (Netherlands)

    Oosterman, B.J.; Land, M.J.; Gaalman, G.J.C.

    2000-01-01

    Several order release methods have been developed for workload control in job shop production. The release methods of the traditional workload control concerts differ in how they deal with the flow of work to each station. Previous research has pointed at strengths and weaknesses of each method.

  6. Remuneration, workload, and allocation of time in general practice.

    NARCIS (Netherlands)

    Berg, M.J. van den; Westert, G.P.; Groenewegen, P.P.; Bakker, D.H. de; Zee, J. van der

    2006-01-01

    Background: General Practitioners (GPs) can cope with workload by, among others, spending more hours in patient care or by spending less time per patient. The way GPs are paid might affect the way they cope with workload. From an economical point of view, capitation payment is an incentive to

  7. Workload demand in police officers during mountain bike patrols

    NARCIS (Netherlands)

    Takken, T.; Ribbink, A.; Heneweer, H.; Moolenaar, H.; Wittink, H.

    2009-01-01

    To the authors' knowledge this is the first paper that has used the training impulse (TRIMP) 'methodology' to calculate workload demand. It is believed that this is a promising method to calculate workload in a range of professions in order to understand the relationship between work demands and

  8. EEG-Based Affect and Workload Recognition in a Virtual Driving Environment for ASD Intervention.

    Science.gov (United States)

    Fan, Jing; Wade, Joshua W; Key, Alexandra P; Warren, Zachary E; Sarkar, Nilanjan

    2018-01-01

    To build group-level classification models capable of recognizing affective states and mental workload of individuals with autism spectrum disorder (ASD) during driving skill training. Twenty adolescents with ASD participated in a six-session virtual reality driving simulator-based experiment, during which their electroencephalogram (EEG) data were recorded alongside driving events and a therapist's rating of their affective states and mental workload. Five feature generation approaches including statistical features, fractal dimension features, higher order crossings (HOC)-based features, power features from frequency bands, and power features from bins () were applied to extract relevant features. Individual differences were removed with a two-step feature calibration method. Finally, binary classification results based on the k-nearest neighbors algorithm and univariate feature selection method were evaluated by leave-one-subject-out nested cross-validation to compare feature types and identify discriminative features. The best classification results were achieved using power features from bins for engagement (0.95) and boredom (0.78), and HOC-based features for enjoyment (0.90), frustration (0.88), and workload (0.86). Offline EEG-based group-level classification models are feasible for recognizing binary low and high intensity of affect and workload of individuals with ASD in the context of driving. However, while promising the applicability of the models in an online adaptive driving task requires further development. The developed models provide a basis for an EEG-based passive brain computer interface system that has the potential to benefit individuals with ASD with an affect- and workload-based individualized driving skill training intervention.

  9. Objective Versus Subjective Measurement of Stress and Social Support: Combat-Related Reactions.

    Science.gov (United States)

    Solomon, Zahava; And Others

    1987-01-01

    Studied combat intensity, social support, and related stress reactions among soldiers who fought in the 1982 Israeli-Lebanon War, comparing those who experienced combat stress reaction (N=382) and those who did not (N=344). Subjective indicators were found to be stronger predictors than were objective indicators. Combat stress reaction was clearly…

  10. Application of LaserBreath-001 for breath acetone measurement in subjects with diabetes mellitus

    Science.gov (United States)

    Wang, Zhennan; Sun, Meixiu; Chen, Zhuying; Zhao, Xiaomeng; Li, Yingxin; Wang, Chuji

    2016-11-01

    Breath acetone is a promising biomarker of diabetes mellitus. With an integrated standalone, on-site cavity ringdown breath acetone analyzer, LaserBreath-001, we tested breath samples from 23 type 1 diabetic (T1D) patients, 312 type 2 diabetic (T2D) patients, 52 healthy subjects. In the cross-sectional studies, the obtained breath acetone concentrations were higher in the diabetic subjects compared with those in the control group. No correlation between breath acetone and simultaneous BG was observed in the T1D, T2D, and healthy subjects. A moderate positive correlation between the mean individual breath acetone concentrations and the mean individual BG levels was observed in the 20 T1D patients without ketoacidosis. In a longitudinal study, the breath acetone concentrations in a T1D patient with ketoacidosis decreased significantly and remained stable during the 5-day hospitalization. The results from a relatively large number of subjects tested indicate that an elevated mean breath acetone concentration exists in diabetic patients in general. Although many physiological parameters affect breath acetone concentrations, fast (diabetic screening and management under a specifically controlled condition.

  11. Sex differences in subjective and actigraphic sleep measures: A population-based study of elderly persons

    NARCIS (Netherlands)

    Berg, J.F. van den; Miedema, H.M.E.; Tulen, J.H.M.; Hofman, A.; Neven, A.K.; Tiemeier, H.

    2009-01-01

    Study Objectives: To investigate and explain sex differences in subjective and actigraphic sleep parameters in community-dwelling elderly persons. Design: Cross-sectional study. Setting: The study was embedded in the Rotterdam Study, a population-based study. Participants: Nine hundred fifty-six

  12. [Measuring facial paralysis using the three-dimensional dynamic quantitative analysis system of facial motion: correlation with subjective grading systems].

    Science.gov (United States)

    Zhao, Y; Feng, G D; Wu, H Y; Zhuang, Y; Gao, Z Q

    2016-07-07

    The aim of this study was to measure the facial motion of patients with facial paralysis using a three-dimensional dynamic quantitative analysis system of facial motion (3D ASFM) and analyze its correlation with subjective grading systems. We included 30 healthy volunteers and 50 patients with unilateral facial paralysis. After placing landmarks on the faces, the facial motions of the patients were measured using the 3D ASFM. The regional symmetry ratios(SRs) and gross scores of different parameters were calculated. Then a comparison with four subjective grading systems(House-Brackmann, Sunnybrook, Facial Nerve Grading System 2.0, Fisch) was performed. The entire test could be completed within five minutes. The normal range of healthy volunteers were obtained, the gross score of which was 91.9±1.5. The SRs of the maximal moving distance(MMD) were most strongly correlated with regional subjective grading systems, followed by the SRs of the maximal moving velocity (MMV). The SRs of the maximal moving acceleration (MMA) were either poorly correlated or uncorrelated with the subjective grading systems. Moreover, the Spearman coefficients with four subjective grading systems were -0.630(House-Brackmann), -0.728(Facial Nerve Grading System 2.0), 0.697(Sunnybrook), and 0.617(Fisch)respectively(Pfacial paralysis. It not only overcomes the shortcomings of conventional subjective grading systems, but also correlates well with them.

  13. A comparative study of autokeratometric and Scheimpflug keratometric measurements of the anterior corneal surface: results for a single subject

    Directory of Open Access Journals (Sweden)

    S. Mathebula

    2007-01-01

    Full Text Available One purpose of the broader study was to determine whether keratometric measurements obtained with an autokeratometer (Nidek ARK-700 would be comparable with those measured using the Oculus Pentacam(model 70700. Ten healthy subjects without ocular abnormality, no previous or current contact lens wear or history of ocular surgery were recruited and at least 43 successive keratometric measurements were obtained for the right eye of each subject using both instruments, namely the autokeratometer and the Pentacam. This paper will concern itself with data from only one of the ten subjects involved, namely Subject 1. The corneal powers were analyzed using multivariate methods for analyzing dioptric power. Scatter plots and meridional profiles of skewness and kurtosis were used to compare the results for the two instruments. Mean dioptric powers in conventional and scientific notation were determined.The results for this subject indicated that there was a statistically significant difference between the autokeratometry and the Pentacam. Although the means  between the two instruments were found to be significantly different at a 95% level of confidence, there was minimal clinical difference between the means of the two instruments. That is, this preliminary investigation suggests that in normal eyes, clinically, keratometric results obtained by means of an autokeratometer and a Pentacam are reasonably similar and can be used interchangeably.

  14. Assessment of Crew Workload for the RAH-66 Comanche Force Development Experiment 1

    National Research Council Canada - National Science Library

    Durbin, David

    2001-01-01

    ...) workload levels contribute to a need to 'battle roster' Comanche pilots. Workload data were collected via the Bedford Workload Rating Scale and a cockpit controls and displays usability questionnaire...

  15. School Nurse Workload: A Scoping Review of Acute Care, Community Health, and Mental Health Nursing Workload Literature

    Science.gov (United States)

    Endsley, Patricia

    2017-01-01

    The purpose of this scoping review was to survey the most recent (5 years) acute care, community health, and mental health nursing workload literature to understand themes and research avenues that may be applicable to school nursing workload research. The search for empirical and nonempirical literature was conducted using search engines such as…

  16. Nursing workload for cancer patients under palliative care.

    Science.gov (United States)

    Fuly, Patrícia Dos Santos Claro; Pires, Livia Márcia Vidal; Souza, Claudia Quinto Santos de; Oliveira, Beatriz Guitton Renaud Baptista de; Padilha, Katia Grillo

    2016-01-01

    To verify the nursing workload required by cancer patients undergoing palliative care and possible associations between the demographic and clinical characteristics of the patients and the nursing workload. This is a quantitative, cross-sectional, prospective study developed in the Connective Bone Tissue (TOC) clinics of Unit II of the Brazilian National Cancer Institute José Alencar Gomes da Silva with patients undergoing palliative care. Analysis of 197 measures of the Nursing Activities Score (NAS) revealed a mean score of 43.09% and an association between the performance status of patients undergoing palliative care and the mean NAS scores. The results of the study point to the need to resize the team of the unit. The NAS has proven to be a useful tool in oncologic clinical units for patients undergoing palliative care. Verificar a carga de trabalho de enfermagem requerida por pacientes com câncer sob cuidados paliativos e possíveis associações entre as características demográficas e clínicas dos pacientes e a carga de trabalho de enfermagem. Trata-se de um estudo de abordagem quantitativa, transversal, prospectivo, desenvolvido na clínica de Tecido Ósseo Conectivo (TOC) da Unidade II do Instituto Nacional de Câncer José Alencar Gomes da Silva, com pacientes em cuidados paliativos. A análise de 197 medidas do Nursing Activities Score (NAS) revelou um escore médio de 43,09% e uma associação entre a performance status de pacientes em cuidados paliativos com os valores médios do NAS. Os resultados do estudo apontam para a necessidade de redimensionamento da equipe da Unidade. O NAS mostrou-se um instrumento passível de utilização em unidades clínicas oncológicas, com pacientes em cuidados paliativos.

  17. A novel noninvasive method for measuring fatigability of the quadriceps muscle in noncooperating healthy subjects

    DEFF Research Database (Denmark)

    Poulsen, Jesper Brøndum; Rose, Martin Høyer; Møller, Kirsten

    2015-01-01

    days, nonvoluntary isometric contractions (twitch and tetanic) of the quadriceps femoris muscle evoked by transcutaneous electrical muscle stimulation were recorded in twelve healthy adults. For tetanic contractions, the Fatigue Index (ratio of peak torque values) and the slope of the regression line......Background. Critical illness is associated with muscle weakness leading to long-term functional limitations. Objectives. To assess the reliability of a novel method for evaluating fatigability of the quadriceps muscle in noncooperating healthy subjects. Methods. On two occasions, separated by seven...... fatigability of the quadriceps muscle produces reliable results in healthy subjects and may provide valuable data on quantitative changes in muscle working capacity and treatment effects in patients who are incapable of producing voluntary muscle contractions....

  18. Measurement of effective alveolar carbon dioxide tension during spontaneous breathing in normal subjects and patients with chronic airways obstruction.

    Science.gov (United States)

    Jordanoglou, J; Koulouris, N; Kyroussis, D; Rapakoulias, P; Vassalos, P; Madianos, J

    1995-03-01

    The measurement of effective alveolar carbon dioxide tension (PA-CO2eff) is still a matter of debate. It has, however, become common practice to use arterial instead of alveolar CO2 tension for computing alveolar oxygen tension (PAO2) and physiological dead space, not only in normal subjects but also in patients. The purpose of this study was to estimate alveolar CO2 tension during spontaneous breathing with a new bedside technique which is simple and non-invasive, and to compare these values with arterial CO2 tension measured in normal subjects and patients with chronic airways obstruction. The subjects breathed quietly through the equipment assembly (mouthpiece, monitoring ring, Fleisch transducer head) connected to a pneumotachograph and a fast response infrared CO2 analyser. The method is a computerised calculation of the volume weighted effective alveolar CO2 tension obtained from the simultaneously recorded expiratory flow and CO2 concentration versus time curves. An arterial blood sample was taken to measure PaCO2 for comparison during the study. The results showed a mean difference (PACO2eff-PaCO2) of -0.205 kPa in 20 normal subjects and -0.460 kPa in 46 patients. The 95% confidence interval of the bias was -0.029 to -0.379 kPa in normal subjects and -0.213 to -0.707 kPa in patients. The limits of agreement between PACO2eff and PaCO2 were 0.526 to -0.935 in normal subjects and 1.170 to -2.088 in patients. The volume weighted effective alveolar PCO2 in normal subjects and patients with chronic airways obstruction is lower than the arterial PCO2 and is recommended as a better estimate in the classical equations for estimating dead space and intrapulmonary shunt.

  19. Changes after voice therapy in objective and subjective voice measurements of pediatric patients with vocal nodules.

    Science.gov (United States)

    Tezcaner, Ciler Zahide; Karatayli Ozgursoy, Selmin; Ozgursoy, Selmin Karatayli; Sati, Isil; Dursun, Gursel

    2009-12-01

    The aim of this study was to analyze the efficiency of the voice therapy in children with vocal nodules by using the acoustic analysis and subjective assessment. Thirty-nine patients with vocal fold nodules, aged between 7 and 14, were included in the study. Each subject had voice therapy led by an experienced voice therapist once a week. All diagnostic and follow-up workouts were performed before the voice therapy and after the third or the sixth month. Transoral and/or transnasal videostroboscopic examination and acoustic analysis were achieved using multi-dimensional voice program (MDVP) and subjective analysis with GRBAS scale. As for the perceptual assessment, the difference was significant for four parameters out of five. A significant improvement was found in the acoustic analysis parameters of jitter, shimmer, and noise-to-harmonic ratio. The voice therapy which was planned according to patients' needs, age, compliance and response to therapy had positive effects on pediatric patients with vocal nodules. Acoustic analysis and GRBAS may be used successfully in the follow-up of pediatric vocal nodule treatment.

  20. Evaluation of Physiologically-Based Artificial Neural Network Models to Detect Operator Workload in Remotely Piloted Aircraft Operations

    Science.gov (United States)

    2016-07-13

    Secondary Score 181.625 5.250 181.031 5.076 Total Score 631.458 20.787 491.113 26.085 Subjective Workload (TLX) 37.404 4.134 42.934 4.025 Heart Rate (Beats...AFRL-RH-WP-TR-2016-0075 Evaluation of Physiologically – Based Artificial Neural Network Models to Detect Operator Workload in Remotely...16 Interim Report 1 August 2015 – 8 July 2016 4. TITLE AND SUBTITLE Evaluation of Physiologically – Based Artificial Neural Network Models to

  1. Measuring Cognitive Load during Simulation-Based Psychomotor Skills Training: Sensitivity of Secondary-Task Performance and Subjective Ratings

    Science.gov (United States)

    Haji, Faizal A.; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-01-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance…

  2. The Beck depression inventory as a measure of subjective well-being : A cross-national study

    NARCIS (Netherlands)

    van Hemert, D.A.; van de Vijver, F.J.R.; Poortinga, Y.H.

    2002-01-01

    The present study examined the question whether the Beck Depression Inventory (BDI), which is one of the most widely used instruments to assess depression, can be used to measure differences in subjective well-being at national level. In order to establish the meaning of depression scores at country

  3. Sonographic measurements of low-echoic synovial area in the dorsal aspect of metatarsophalangeal joints in healthy subjects.

    Science.gov (United States)

    Hiraga, Masao; Ikeda, Kei; Shigeta, Koichiro; Sato, Akito; Yoshitama, Tamami; Hara, Ryota; Tanaka, Yasuhito

    2015-05-01

    Assessment of synovitis in the metatarsophalangeal (MTP) joints with ultrasound has been shown to improve the accuracy of assessment of rheumatoid arthritis (RA). However, the presence of intraarticular low-echoic synovial area (LESA) in the MTP joints in healthy subjects complicates the sonographic assessment of these joints. Healthy subjects with no arthritic symptoms in their MTP joints were recruited. All subjects completed a questionnaire and underwent physical examination and sonographic assessment. LESAs in the dorsal aspect of all MTP joints were measured in the longitudinal view. One thousand non-arthritic MTP joints in 100 healthy subjects (female 73, mean age 41.0 years old) were evaluated. Measurable LESAs were identified in all joints assessed. Mean length of LESA in each of the 1st-5th MTP joints was 17.8, 13.9, 11.9, 10.6, and 9.2 mm, respectively, whereas mean thickness was 2.4, 2.4, 1.8, 1.2, and 0.8 mm, respectively. Multivariate linear regression models identified the difference between 1st and 5th MTP joints as the most independently influential factor on the measurement of LESA. Our data provide the normal reference values for the measurements of LESA in Japanese, which should be taken into consideration when the synovitis in MTP joints is evaluated with ultrasound.

  4. Validation of reaction time as a measure of cognitive function and quality of life in healthy subjects and patients

    DEFF Research Database (Denmark)

    Jakobsen, Lene Holm; Sorensen, Janice Marie; Rask, Ingeborg Krarup

    2011-01-01

    Malnutrition is a common problem in hospitalized patients and is related to decreased cognitive function and impaired quality of life (QoL). We investigated the validity of reaction time as a simple bedside tool for measuring cognitive function in healthy subjects and patients, and additionally...

  5. Non-invasive perilymphatic pressure measurement in normal hearing subjects using the MMS-10 tympanic displacement analyser

    NARCIS (Netherlands)

    Rosingh, HJ; Wit, HP; Albers, FWJ

    The MMS-10 Tympanic Displacement Analyser (TDA) is a new device to measure the perilymphatic pressure of the human inner ear in a non-invasive way. In this study, the instrument was used in 50 normal hearing subjects (100 ears) in three different conditions: i) sitting upright and supine; ii) in the

  6. Time-course analysis of stretch reflexes in hemiparetic subjects using an on-line spasticity measurement system.

    Science.gov (United States)

    Ju, M S; Chen, J J; Lee, H M; Lin, T S; Lin, C C; Huang, Y Z

    2000-02-01

    Spasticity after a stroke is usually assessed in a score form by subjectively determining the resistance of a joint to an externally imposed passive movement. This work presents a spasticity measurement system for on-line quantifying the stretch reflex of paretic limbs. Four different constant stretch velocities in a ramp-and-hold mode are used to elicit the stretch reflex of the elbow joint in spastic subjects. The subjects are tested at supine position with the upper limb stretched towards the ground, in contrast with the horizontally stretched movement used in other studies. By subtracting the baseline torque, reflex torque measured at a selected low stretch velocity of 5 deg/sec, the influence of gravity torque and inertial in vertical stretching mode can be minimized. The averaged speed-dependent reflex torque (ASRT), defined as the measured torque deviated from the baseline torque, is used for quantifying the spastic hypertonia. Four subjects having incurred cerebrovascular accident (CVA) are recruited for time-course study in which the measurements are taken at 72 hours, one week, one month, three months, and six months after onset of stroke. During the development of spasticity, the changes of ASRT and velocity sensitivity of ASRT of the involved and the intact elbow joints are discussed.

  7. Effects of Blast Exposure on Subjective and Objective Sleep Measures in Combat Veterans with and without PTSD.

    Science.gov (United States)

    Stocker, Ryan P J; Paul, Benjamin T E; Mammen, Oommen; Khan, Hassen; Cieply, Marissa A; Germain, Anne

    2016-01-01

    This study examined the extent to which self-reported exposure to blast during deployment to Iraq and Afghanistan affects subjective and objective sleep measures in service members and veterans with and without posttraumatic stress disorder (PTSD). Seventy-one medication-free service members and veterans (mean age = 29.47 ± 5.76 years old; 85% men) completed self-report sleep measures and overnight polysomnographic studies. Four multivariate analyses of variance (MANOVAs) were conducted to examine the impact of blast exposure and PTSD on subjective sleep measures, measures of sleep continuity, non-rapid eye movement (NREM) sleep parameters, and rapid eye movement (REM) sleep parameters. There was no significant Blast × PTSD interaction on subjective sleep measures. Rather, PTSD had a main effect on insomnia severity, sleep quality, and disruptive nocturnal behaviors. There was no significant Blast × PTSD interaction, nor were there main effects of PTSD or Blast on measures of sleep continuity and NREM sleep. A significant PTSD × Blast interaction effect was found for REM fragmentation. The results suggest that, although persistent concussive symptoms following blast exposure are associated with sleep disturbances, self-reported blast exposure without concurrent symptoms does not appear to contribute to poor sleep quality, insomnia, and disruptive nocturnal disturbances beyond the effects of PTSD. Reduced REM sleep fragmentation may be a sensitive index of the synergetic effects of both psychological and physical insults. © 2016 American Academy of Sleep Medicine.

  8. Validation Study of a General Subject-matter Interest Measure: The Individual Interest Questionnaire (IIQ

    Directory of Open Access Journals (Sweden)

    Jerome I. Rotgans

    2015-12-01

    Conclusion and relevance: The results suggest that the IIQ is a reliable and valid instrument to measure individual interest across different disciplines and demonstrated adequate predictive validity for cognitive engagement and on-task behaviors and attitudes. The IIQ fills the gap in the literature for a generic instrument to measure individual interest.

  9. Prediction of walking speed using single stance force or pressure measurements in healthy subjects

    NARCIS (Netherlands)

    Keijsers, N.L.W.; Stolwijk, N.M.; Renzenbrink, G.J.; Duysens, J.

    2016-01-01

    Walking speed is one of the best measures of overall walking capacity. In plantar pressure measurements, walking speed can be assessed using contact time, but it is only moderately correlated with walking speed. The center of pressure might be of more value to indicate walking speed since walking

  10. Question order sensitivity of subjective well-being measures: focus on life satisfaction, self-rated health, and subjective life expectancy in survey instruments.

    Science.gov (United States)

    Lee, Sunghee; McClain, Colleen; Webster, Noah; Han, Saram

    2016-10-01

    This study examines the effect of question context created by order in questionnaires on three subjective well-being measures: life satisfaction, self-rated health, and subjective life expectancy. We conducted two Web survey experiments. The first experiment (n = 648) altered the order of life satisfaction and self-rated health: (1) life satisfaction asked immediately after self-rated health; (2) self-rated health immediately after life satisfaction; and (3) two items placed apart. We examined their correlation coefficient by experimental condition and further examined its interaction with objective health. The second experiment (n = 479) asked life expectancy before and after parental mortality questions. Responses to life expectancy were compared by order using ANOVA, and we examined interaction with parental mortality status using ANCOVA. Additionally, response time and probes were examined. Correlation coefficients between self-rated health and life satisfaction differed significantly by order: 0.313 (life satisfaction first), 0.508 (apart), and 0.643 (self-rated health first). Differences were larger among respondents with chronic conditions. Response times were the shortest when self-rated health was asked first. When life expectancy asked after parental mortality questions, respondents reported considering parents more for answering life expectancy; and respondents with deceased parents reported significantly lower expectancy, but not those whose parents were alive. Question context effects exist. Findings suggest placing life satisfaction and self-rated health apart to avoid artificial attenuation or inflation in their association. Asking about parental mortality prior to life expectancy appears advantageous as this leads respondents to consider parental longevity more, an important factor for true longevity.

  11. Foveal slope measurements in subjects with high-risk of age-related macular degeneration

    Directory of Open Access Journals (Sweden)

    Rajiv Raman

    2013-01-01

    Full Text Available Background: Recent reports indicated that the slope of the foveal depression influences the macular pigment (MP spatial profile. MP has been shown to confer possible protection against age-related macular degeneration (ARMD because of its antioxidant properties. Aims: To study the configuration of foveal slope and the foveal thickness in fellow eyes of subjects with unilateral neovascular ARMD. Settings and design: Case-control series. Materials and Methods: The study population consisted of 30 cases aged >50, who had unilateral choroidal neovascular membrane (CNVM or disciform scar in the fellow eye and 29 controls aged >50, who had no sign of ARMD in the either eye. Using spectral-domain optical coherence tomography, foveal thickness at different locations including the central subfield foveal thickness (CSFT was noted. The foveal slopes were calculated in the six radial scans (between 0.25° and 1° retinal eccentricity as well as the 3D scan. Results: Cases had a significantly higher CSFT when compared to controls (215.1 ± 36.19 μ vs. 193.0 ± 17.38 μ, P = 0.004. On the 3D scan, the cases had shallower superior (cases 1.32 ± 0.32 vs. controls 1.45 ± 0.13, P = 0.04 and temporal slopes (cases 1.27 ± 0.21 vs. controls 1.39 ± 0.12, P = 0.01 in comparison to the controls. Conclusions: We noted a shallower superior and temporal foveal slope and a higher CSFT in the fellow eyes of subjects with a unilateral neovascular ARMD. Prospective studies observing the development of CNVM in subjects with altered foveal slope might provide more information on this optical coherence tomography finding.

  12. Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging-measured adipose tissue depots in both HIV-infected and control subjects.

    Science.gov (United States)

    Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Heymsfield, Steven B; Grunfeld, Carl

    2008-06-01

    Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects. We compared anthropometric and magnetic resonance imaging (MRI)-based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects. The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors. In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r measures, and the magnitudes of differences were small (adjusted R(2) measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects.

  13. Cognitive Components Predict Virtual Reality-Induced Analgesia: Repeated Measures in Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Naor Demeter

    2018-01-01

    Full Text Available Virtual reality (VR is an advanced and useful technology in the distraction from pain. The efficacy of VR for reducing pain is well established. Yet, the literature analyzing the unique attributes of VR which impact pain reduction is scarce. The present study evaluated the effect of two VR environments on experimental pain levels. Both VR environments are games used with an EyeToy application which is part of the video capture VR family. The VR environments were analyzed by expert occupational therapists using a method of activity analysis, allowing for a thorough evaluation of the VR activity performance requirements. The VR environments were found to differ in the cognitive load (CL demands they apply upon subjects. Sixty-two healthy students underwent psychophysical thermal pain tests, followed by exposure to tonic heat stimulation under one of three conditions: Low CL (LCL VR, high CL (HCL VR, and control. In addition, following participation in VR, the subjects completed a self-feedback inventory evaluating their experience in VR. The results showed significantly greater pain reduction during both VR conditions compared to the control condition (p = 0.001. Hierarchical regression revealed cognitive components which were evaluated in the self-feedback inventory to be predictive factors for pain reduction only during the high cognitive load (HCL VR environment (20.2%. CL involved in VR may predict the extent of pain decrease, a finding that should be considered in future clinical and laboratory research.

  14. Reproducibility and repeatability of foveal avascular zone area measurements using swept-source optical coherence tomography angiography in healthy subjects.

    Science.gov (United States)

    Mastropasqua, Rodolfo; Toto, Lisa; Mattei, Peter A; Di Nicola, Marta; Zecca, Isaia A L; Carpineto, Paolo; Di Antonio, Luca

    2017-05-11

    To assess the reproducibility and repeatability of foveal avascular zone (FAZ) area measurements using swept-source optical coherence tomography angiography (SS-OCTA) in healthy subjects. Sixty-four eyes of 64 healthy volunteers were randomly subjected to FAZ area measurements using SS-OCTA by 2 examiners in 2 different sessions. The FAZ areas measured by the first and second observer were 0.269 ± 0.092 mm2 and 0.270 ± 0.090 mm2, respectively. Within subjects, the coefficients of variations were 2.44% (95% confidence interval [CI] 1.95% to 2.93%) and 2.66% (95% CI 2.00% to 3.31%) for the first and second observers, respectively. The coefficient of repeatability average measurements of FAZ area were 0.021 mm2 and 0.024 mm2. The intraclass correlation coefficient values were 0.993 (95% CI 0.989 to 0.996) and 0.991 (95% CI 0.986 to 0.995). Interobserver and intraobserver concordance correlation coefficients ranged from 0.998 (95% CI 0.997 to 0.999) to 0.999 (95% CI 0.998 to 0.999) and from 0.989 (95% CI 0.982 to 0.993) to 0.987 (95% CI 0.979 to 0.992), respectively. The FAZ area measurements by means of SS-OCTA showed high reproducibility and repeatability in healthy eyes.

  15. Objective measurement of daytime napping, cognitive dysfunction and subjective sleepiness in Parkinson's disease

    National Research Council Canada - National Science Library

    Bolitho, Samuel J; Naismith, Sharon L; Salahuddin, Pierre; Terpening, Zoe; Grunstein, Ron R; Lewis, Simon J G

    2013-01-01

    .... The current study used daytime actigraphy, a novel objective measure of napping and related this to neuropsychological performance in a sample of PD patients and healthy, age and gender-matched controls...

  16. Objective Measurement of Daytime Napping, Cognitive Dysfunction and Subjective Sleepiness in Parkinsons Disease: e81233

    National Research Council Canada - National Science Library

    Samuel J Bolitho; Sharon L Naismith; Pierre Salahuddin; Zoe Terpening; Ron R Grunstein; Simon J G Lewis

    2013-01-01

    .... The current study used daytime actigraphy, a novel objective measure of napping and related this to neuropsychological performance in a sample of PD patients and healthy, age and gender-matched controls...

  17. Wealth, justice and freedom: Objective and subjective measures predicting poor mental health in a study across eight countries.

    Science.gov (United States)

    Scholten, Saskia; Velten, Julia; Neher, Torsten; Margraf, Jürgen

    2017-12-01

    Macro-level factors (MF) such as wealth, justice and freedom measured with objective country-level indicators (objective MF), for instance the Gross Domestic Product (GDP), have been investigated in relation to health and well-being, but rarely in connection with depression, anxiety and stress subsumed as poor mental health. Also, a combination of different objective MF and of how individuals perceive those MF (subjective MF) has not been taken into consideration. In the present study, we combined subjective and objective measures of wealth, justice and freedom and examined their relationship with poor mental health. Population-based interviews were conducted in France, Germany, Poland, Russia, Spain, Sweden, U.K. and U.S.A. (n ≈ 1000 per country). GDP, GINI coefficient, Justice Index and Freedom Index were used as objective MF, whereas subjective MF were perceived wealth, justice and freedom measured at the individual level. Poor mental health was assessed as a combination of symptoms of depression, anxiety and stress. In a random-intercept-model, GINI coefficient and Freedom Index were significant positive country-level, and perceived wealth, justice, and freedom significant negative individual-level predictors of symptoms of poor mental health. Multiple subjective and objective MF should be combined to assess the macrosystem's relationship with poor mental health more precisely. The relationship between MF and poor mental health indicates that the macrosystem should be taken into account as relevant context for mental health problems, too.

  18. Emotional Exhaustion and Workload Predict Clinician-Rated and Objective Patient Safety

    Directory of Open Access Journals (Sweden)

    Annalena eWelp

    2015-01-01

    Full Text Available Aims: To investigate the role of clinician burnout, demographic and organizational characteristics in predicting subjective and objective indicators of patient safety. Background: Maintaining clinician health and ensuring safe patient care are important goals for hospitals. While these goals are not independent from each other, the interplay between clinician psychological health, demographic and organizational variables and objective patient safety indicators is poorly understood. The present study addresses this gap. Method: Participants were 1425 physicians and nurses working in intensive care. (Multilevel regression analysis was used to investigate the effect of burnout as an indicator of psychological health, demographic (e.g., professional role and experience and organizational (e.g., workload, predictability characteristics on standardized mortality ratios, length of stay and clinician-rated patient safety. Results: Clinician-rated patient safety were associated with burnout, trainee status, and professional role. Mortality was predicted by emotional exhaustion. Length of stay was predicted by workload. Contrary to our expectations, burnout did not predict length of stay, and workload and predictability did not predict standardized mortality ratios.Conclusion: At least in the short-term, clinicians seem to be able to maintain safety despite high workload and low predictability. Nevertheless, burnout poses a safety risk. Subjectively, burnt-out clinicians rated safety lower, and objectively, units with high emotional exhaustion had higher standardized mortality ratios. In summary, our results indicate that clinician psychological health and patient safety could be managed simultaneously. Further research needs to establish causal relationships between these variables or and support the development of managerial guidelines to ensure clinicians’ psychological health and patients’ safety.

  19. Emotional exhaustion and workload predict clinician-rated and objective patient safety

    Science.gov (United States)

    Welp, Annalena; Meier, Laurenz L.; Manser, Tanja

    2015-01-01

    Aims: To investigate the role of clinician burnout, demographic, and organizational characteristics in predicting subjective and objective indicators of patient safety. Background: Maintaining clinician health and ensuring safe patient care are important goals for hospitals. While these goals are not independent from each other, the interplay between clinician psychological health, demographic and organizational variables, and objective patient safety indicators is poorly understood. The present study addresses this gap. Method: Participants were 1425 physicians and nurses working in intensive care. Regression analysis (multilevel) was used to investigate the effect of burnout as an indicator of psychological health, demographic (e.g., professional role and experience) and organizational (e.g., workload, predictability) characteristics on standardized mortality ratios, length of stay and clinician-rated patient safety. Results: Clinician-rated patient safety was associated with burnout, trainee status, and professional role. Mortality was predicted by emotional exhaustion. Length of stay was predicted by workload. Contrary to our expectations, burnout did not predict length of stay, and workload and predictability did not predict standardized mortality ratios. Conclusion: At least in the short-term, clinicians seem to be able to maintain safety despite high workload and low predictability. Nevertheless, burnout poses a safety risk. Subjectively, burnt-out clinicians rated safety lower, and objectively, units with high emotional exhaustion had higher standardized mortality ratios. In summary, our results indicate that clinician psychological health and patient safety could be managed simultaneously. Further research needs to establish causal relationships between these variables and support to the development of managerial guidelines to ensure clinicians’ psychological health and patients’ safety. PMID:25657627

  20. Determination of Work-Rest Schedules Based on Physical Workload Among Bakers in Ahvaz, Iran

    Directory of Open Access Journals (Sweden)

    Davood Afshari

    2016-09-01

    Full Text Available Background Bakery workers due to exposure to radiant heat and doing manual labor are at risk of heat-related illnesses and musculoskeletal disorders Objectives The current study aimed to determine the appropriate work-rest time interval using two indexes of wet bulb globe temperature (WBGT and relative heart rate (RHR. Methods It was an analytical and descriptive research. Heart rate of workers was continuously recorded to achieve the physiological monitoring and the obtained information was used to determine the work difficulty and physical workload. The ratio of heat stress and RHR was measured using the WBGT and polar team pro device, respectively. Work-rest schedules were detected through the heart rate reserve and heat stress indexes. The level of significance was α = 0.05. Results Physical workload based on heart rate was estimated light to moderate in bakery workers. Suitable work-rest schedule for all bakery workers according to WBGT index was 25% work-75% rest and based on heart rate reserve index in half of the workers was 50% work-50% rest, and in the other half of the bakery workers was continuous work without rest. According to Kappa test, there was no agreement between the two methods of heat stress index and heart rate reserve to determine the work-rest schedules of workers (P < 0.001. Conclusions Physical workloads on the basis of heart rate were light for all workers except the workers of Tanoury who had moderate workload. Meanwhile, determining the work-rest schedule was different using the two indexes. The heart rate reserve index represents the physiological status of individual during the work and states the ratio of physical workload more precisely.

  1. Subjective and Objective Measures in the Treatment of Hemifacial Spasm With OnabotulinumtoxinA.

    Science.gov (United States)

    Chundury, Rao V; D'Angelo, Alexander S; Couch, Steven M; Holds, John B

    2016-01-01

    To evaluate the Sunnybrook Facial Grading System (SFGS) and Facial Clinimetric Evaluation (FaCE) Scale Instrument outcomes when treating hemifacial spasm (HFS) with onabotulinumtoxinA. An Institutional Review Board-approved retrospective review of records of 66 HFS patients treated with onabotulinumtoxinA. SFGS and FaCE surveys were completed prior to onabotulinumtoxinA therapy and at 1 month follow up. Surveys were analyzed for differences using paired Student t tests, with statistical significance set at p < 0.05. Correlations were determined using Spearman correlation (rs), with coefficients of ≥0.40 or ≤-0.40 considered significant. There were 22 complete data sets. SFGS composite score improved from mean, 56.9 (SD, 12.3) to 63.6 (SD, 12.3), p < 0.01. SFGS subdomain synkinesis score significantly improved (p < 0.01). The FaCE scale subdomain oral function significantly worsened (p = 0.05). The Δ pre-/post-SFGS composite score did not correlate with the Δ pre-/post-FaCE composite score (rs = 0.24). There was a significant positive correlation between SFGS composite score and FaCE social function score (rs = 0.462, p = 0.03) and between SFGS voluntary movement score and FaCE social function score (rs = 0.477, p = 0.03). Subgroup analysis of single FaCE questions demonstrated no statistical change in subjective dry eye (p = 0.30). There was an improvement in social functioning in treated HFS patients, which positively correlated with improvement in overall objective voluntary facial movement. There was no statistical difference in subjective dry eye symptoms. The overall SFGS composite score improved following treatment of HFS with botulinum toxin. This information can be used when counseling expected outcomes in HFS patients treated with onabotulinumtoxinA.

  2. Benefits of a short, practical questionnaire to measure subjective perception of nasal appearance after aesthetic rhinoplasty.

    Science.gov (United States)

    Lohuis, Peter J F M; Hakim, Sara; Duivesteijn, Wouter; Knobbe, Arno; Tasman, Abel-Jan

    2013-12-01

    The authors tested a short, practically designed questionnaire to assess changes in subjective perception of nasal appearance in patients before and after aesthetic rhinoplasty. A prospective cohort study was conducted in a group of 121 patients who desired aesthetic rhinoplasty and were operated on by one surgeon. The questionnaire contained five questions (E1-E5) based on a five-point Likert scale and a visual analogue scale (range, 0 to 10). Two questions were designed as trick questions to help the surgeon screen for signs of body dysmorphic disorder. All patients rated the appearance of their nose as improved after surgery. The visual analogue scale revealed a Gaussian curve of normal distribution (range, 0.5 to 10) around a significant improvement (mean, 4.36 points, p = 0.018). Also, question E1, question E2, and the sum of questions E1 through E5 showed a statistically significant improvement after surgery (p = 1.74 × 10, p = 4.29 × 10, and p = 9.23 × 10, respectively). The authors found a linear relationship between preoperative score on the trick questions and postoperative increase in visual analogue scale score. Test-retest reliability could be investigated in 74 of 121 patients (61 percent) and showed a positive correlation between postoperative (1 year after surgery) and repostoperative response (2 to 4 years after surgery). The authors concluded that a surgeon performing aesthetic rhinoplasty can benefit from using this questionnaire. It is simple, takes no more than 2 minutes to complete, and provides helpful subjective information regarding patients' preoperative nasal appearance and postoperative surgical outcome. Therapeutic, IV.

  3. Assessment of physical workload in boiler operations.

    Science.gov (United States)

    Rodrigues, Valéria Antônia Justino; Braga, Camila Soares; Campos, Julio César Costa; Souza, Amaury Paulo de; Minette, Luciano José; Sensato, Guilherme Luciano; Moraes, Angelo Casali de; Silva, Emília Pio da

    2012-01-01

    The use of boiler wood-fired is fairly common equipment utilized in steam generation for energy production in small industries. The boiler activities are considered dangerous and heavy, mainly due to risks of explosions and the lack of mechanization of the process. This study assessed the burden of physical labor that operators of boilers are subjected during the workday. Assessment of these conditions was carried out through quantitative and qualitative measurements. A heart rate monitor, a wet-bulb globe thermometer (WBGT), a tape-measure and a digital infrared camera were the instruments used to collect the quantitative data. The Nordic Questionnaire and the Painful Areas Diagram were used to relate the health problems of the boiler operator with activity. With study, was concluded that the boiler activity may cause pains in the body of intensity different, muscle fatigue and diseases due to excessive weight and the exposure to heat. The research contributed to improve the boiler operator's workplace and working conditions.

  4. The effects of receiver placement on probe microphone, performance, and subjective measures with open canal hearing instruments.

    Science.gov (United States)

    Alworth, Lynzee N; Plyler, Patrick N; Reber, Monika Bertges; Johnstone, Patti M

    2010-04-01

    Open canal hearing instruments differ in method of sound delivery to the ear canal, distance between the microphone and the receiver, and physical size of the devices. Moreover, RITA (receiver in the aid) and RITE (receiver in the ear) hearing instruments may also differ in terms of retention and comfort as well as ease of use and care for certain individuals. What remains unclear, however, is if any or all of the abovementioned factors contribute to hearing aid outcome. To determine the effect of receiver location on performance and/or preference of listeners using open canal hearing instruments. An experimental study in which subjects were exposed to a repeated measures design. Twenty-five adult listeners with mild sloping to moderately severe sensorineural hearing loss (mean age 67 yr). Participants completed two six-week trial periods for each device type. Probe microphone, objective, and subjective measures (quiet, noise) were conducted unaided and aided at the end of each trial period. Occlusion effect results were not significantly different between the RITA and RITE instruments; however, frequency range was extended in the RITE instruments, resulting in significantly greater maximum gain for the RITE instruments than the RITA instruments at 4000 and 6000 Hz. Objective performance in quiet or in noise was unaffected by receiver location. Subjective measures revealed significantly greater satisfaction ratings for the RITE than for the RITA instruments. Similarly, preference in quiet and overall preference were significantly greater for the RITE than for the RITA instruments. Although no occlusion differences were noted between instruments, the RITE did demonstrate a significant difference in reserve gain before feedback at 4000 and 6000 Hz. Objectively; no positive benefit was noted between unaided and aided conditions on speech recognition tests. These results suggest that such testing may not be sensitive enough to determine aided benefit with open canal

  5. Effect of Single Administration of Coffee on Pupil Size and Ocular Wavefront Aberration Measurements in Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Handan Bardak

    2016-01-01

    Full Text Available No study has so far evaluated the impact of coffee drinking on ocular wavefront aberration (OWA measurements. This study presents novel findings regarding the OWA of the eye following coffee intake. We aimed to evaluate the acute changes in pupil size and OWA of the eye after single administration of coffee. A total of 30 otherwise healthy participants were included in this prospective study. All subjects drank a cup of coffee containing 57 mg caffeine. Measurements of pupil size, total coma (TC, total trefoil (TF, total spherical aberration (TSA, and total higher order aberration (HOA were performed before and at 5 minutes, at 30 minutes, and at 4 hours after coffee drinking using a wavefront aberrometer device (Irx3, Imagine Eyes, Orsay, France. The mean age of the study population was 20.30 ± 2.74 years. Pupil size did not show a significant change during the measurements (p>0.05. A significant increase was observed in TF and HOA measurements following coffee intake (p=0.029 and p=0.009, resp.. Single administration of coffee results in significant increase in TF and total HOAs in healthy subjects without any effect on pupil diameter. Ultrastructural changes in the cornea following coffee intake might be of relevance to the alterations in ocular aberrations in healthy subjects.

  6. Comparison between ankle proprioception measurements and postural sway test for evaluating ankle instability in subjects with functional ankle instability.

    Science.gov (United States)

    Kim, Chang-Yong; Choi, Jong-Duk

    2016-01-01

    It is important to establish the effective evaluation approaches that are appropriate for measuring ankle proprioception. But, only a few studies used more than one test procedure simultaneously to identify proprioceptive deficits. Further, no data are available on the correlations between the measures of ankle proprioception and postural sway (PS) test in subjects with functional ankle instability (FAI). The aim of this study was to identify the relationship between ankle proprioception measurements and PS test in subjects with FAI. Of the 79 subjects enrolled in the case-control study, 40 had FAI and 39 were control subjects. Ankle proprioception was evaluated by the angle reproduction (AR), force matching (FM), and the muscle reaction (MR) to sudden ankle inversion tests. For the AR and FM tests, absolute errors (AE) of ankle plantarflexion, dorsiflexion, inversion, and eversion directions were calculated. For the MR test, reaction times and activation of tibialis anterior (TA), peroneus longus (PL), and peroneus brevis (PB) muscles were measured during sudden ankle inversion with a 30° tilting angle. The PS test was investigated by using a force platform during single-limb standing test. Three trials were performed and averaged in each test. Reaction time of the PL (p = 0.006), a variable of MR test, and plantarflexion (p = 0.001, p = 0.009) and eversion (p = 0.016, p = 0.039) error variables of the AR and FM tests differed significantly between the control and FAI groups. Moreover, these variables (r = -0.381 ∼ 0.788, p proprioception measurements were more sensitive and discriminative than others, and could be useful to assess ankle instability, particularly if the method is to be applied in clinical studies and laboratory settings.

  7. Blinking and driving: the influence of saccades and cognitive workload.

    Science.gov (United States)

    Cardona, Genís; Quevedo, Noa

    2014-03-01

    The aim of this study was to investigate the joint influence of cognitive demands and large amplitude saccades on spontaneous blink rate. Twenty healthy volunteers were enrolled in the study and instructed to follow a 60-minute real-life driving circuit while a video camera recorded ocular movements and blinking. Five different complexity levels were predefined in terms of driving difficulty and traffic intensity, that is, cognitive workload. Five one-minute segments were selected for each complexity level in each driving trial, whereupon spontaneous blink rate and horizontal saccades were monitored. Saccades were classified according to their amplitude and blink-saccade pairs were recorded. Albeit showing a high inter-subject variability, spontaneous blink rate and saccades were consistent within the same complexity level. At different complexity levels, no statistically significant difference in spontaneous blink rate was encountered, with an average of 20.3 ± 1.6 blinks/minute (mean ± SD). The number of large amplitude gaze shifts increased with the level of complexity (F = 15.403; p blink, and this percentage was similar for all complexity levels, that is, the number of blink-saccade pairs increased at higher complexity levels (F = 20.597; p blinking accompanying large amplitude saccades may help in counteracting the reduction in blink rate associated with high cognitive demands.

  8. Relationship Between Pretraining Subjective Wellness Measures, Player Load, and Rating-of-Perceived-Exertion Training Load in American College Football.

    Science.gov (United States)

    Govus, Andrew D; Coutts, Aaron; Duffield, Rob; Murray, Andrew; Fullagar, Hugh

    2018-01-01

    The relationship between pretraining subjective wellness and external and internal training load in American college football is unclear. To examine the relationship of pretraining subjective wellness (sleep quality, muscle soreness, energy, wellness Z score) with player load and session rating of perceived exertion (s-RPE-TL) in American college football players. Subjective wellness (measured using 5-point, Likert-scale questionnaires), external load (derived from GPS and accelerometry), and s-RPE-TL were collected during 3 typical training sessions per week for the second half of an American college football season (8 wk). The relationship of pretraining subjective wellness with player load and s-RPE training load was analyzed using linear mixed models with a random intercept for athlete and a random slope for training session. Standardized mean differences (SMDs) denote the effect magnitude. A 1-unit increase in wellness Z score and energy was associated with trivial 2.3% (90% confidence interval [CI] 0.5, 4.2; SMD 0.12) and 2.6% (90% CI 0.1, 5.2; SMD 0.13) increases in player load, respectively. A 1-unit increase in muscle soreness (players felt less sore) corresponded to a trivial 4.4% (90% CI -8.4, -0.3; SMD -0.05) decrease in s-RPE training load. Measuring pretraining subjective wellness may provide information about players' capacity to perform in a training session and could be a key determinant of their response to the imposed training demands American college football. Hence, monitoring subjective wellness may aid in the individualization of training prescription in American college football players.

  9. Automated short-axis cardiac magnetic resonance image acquisitions: accuracy of left ventricular dimension measurements in normal subjects and patients.

    Science.gov (United States)

    Danilouchkine, Mikhail G; Westenberg, Jos J M; Reiber, Johan H C; Lelieveldt, Boudewijn P F

    2004-12-01

    This study investigates the use of an automated observer-independent planning system for short-axis cardiovascular magnetic resonance (MR) acquisitions in the clinical environment. The capacity of the automated method to produce accurate measurements of left ventricular dimensions and function was quantitatively assessed in normal subjects and patients. Fourteen healthy volunteers and 8 patients underwent cardiovascular MR (CMR) acquisitions for ventricular function assessment. Short-axis datasets of the left ventricle (LV) were acquired in 2 ways: manually planned and generated in an automatic fashion. End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), and left ventricular mass (LVM) were derived from the 2 datasets. The agreement between the manual and automatic planning methods was assessed. The mean differences between the manual and automated CMR planning methods for the normal subjects and patients were 5.89 mL and 1.93 mL (EDV), 1.14 mL and -0.41 mL (ESV), 0.81% and 0.89% (EF), and 4.35 g and 3.88 g (LVM), respectively. There was no significant difference in ESV and EF. LVM significantly differed in both groups, whereas EDV was significantly different in the normal subjects and insignificantly different in the patients. The variability coefficients were 2.8 and 3.59 (EDV), 3.3 and 5.03 (ESV), 1.79 and 2.65 (EF), and 4.36 and 2.27 (LVM) for the normal subjects and patients, respectively. The mean angular deviation of the LV axes turned out to be 8.58 +/- 5.76 degrees for the normal subjects and 8.35 +/- 5.15 degrees for the patients. Automated CMR planning method can provide accurate measurements of LV dimensions in normal subjects and patients, and therefore, can be used in the clinical environment for functional assessment of the human cardiovascular system.

  10. Effect of quality of life measures on the decision to remove third molars in subjects with mild pericoronitis symptoms.

    Science.gov (United States)

    Tang, Dana T; Phillips, Ceib; Proffit, William R; Koroluk, Lorne D; White, Raymond P

    2014-07-01

    To assess how quality of life (QoL) measures affect the decision for third molar (3M) removal in patients with mild symptoms of pericoronitis. Healthy subjects, aged 18 to 35 years, with mild symptoms of pericoronitis were enrolled in an institutional review board-approved study. The demographic, clinical, and QoL data were collected at enrollment. The subjects voluntarily scheduled surgery for 3M removal. The principal outcome variable was their decision to undergo or not undergo surgery within 6 months of enrollment. The possible predictor variables in a multivariate logistic regression analysis were the demographic characteristics, dental insurance, and QoL measures. The mean age of the 113 subjects was 23.2 ± 3.8 years. Of the 113 subjects, 79 elected to undergo 3M removal within 6 months of enrollment (removed group) and 34 elected to retain their 3M at 6 months after enrollment (retained group). A significantly greater proportion of the removed group were white (58% vs 35%; P = .03) and reported having at least "a little trouble" with opening their mouths (38% vs 18%; P = .04) and taking part in social life (27% vs 6%; P = .01). The multivariate logistic regression model suggested the odds of electing 3M removal within 6 months of enrollment were greater for those who were white (odds ratio [OR] 2.69, 95% confidence interval [CI] 1.14 to 6.32) and those who had at least "a little trouble" with interactions in their social life (OR 3.22, 95% CI 1.08 to 9.58). In subjects with mild pericoronitis symptoms, experiencing problems with oral function and lifestyle, factors not often considered by clinicians, were significantly associated with subjects' decision for early 3M removal. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  11. The effect of subjective awareness measures on performance in artificial grammar learning task.

    Science.gov (United States)

    Ivanchei, Ivan I; Moroshkina, Nadezhda V

    2018-01-01

    Systematic research into implicit learning requires well-developed awareness-measurement techniques. Recently, trial-by-trial measures have been widely used. However, they can increase complexity of a study because they are an additional experimental variable. We tested the effects of these measures on performance in artificial grammar learning study. Four groups of participants were assigned to different awareness measures conditions: confidence ratings, post-decision wagering, decision strategy attribution or none. Decision-strategy-attribution participants demonstrated better grammar learning and longer response times compared to controls. They also exhibited a conservative bias. Grammaticality by itself was a stronger predictor of strings endorsement in decision-strategy-attribution group compared to other groups. Confidence ratings and post-decision wagering only affected the response times. These results were supported by an additional experiment that used a balanced chunk strength design. We conclude that a decision-strategy-attribution procedure may force participants to adopt an analytical decision-making strategy and rely mostly on conscious knowledge of artificial grammar. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Measuring craving: An attempt to connect subjective craving with cue reactivity

    NARCIS (Netherlands)

    Ooteman, W.; Koeter, M.W.J.; Vserheul, R.; Schippers, G.M.; van den Brink, W.

    2006-01-01

    Background: Better insight into craving may contribute to the development of more efficient relapse prevention strategies. Inconsistent findings on the relation between craving and relapse may be due to difficulties in the measurement of craving. These difficulties are accounted for by 3

  13. SARDA HITL Preliminary Human Factors Measures and Analyses

    Science.gov (United States)

    Hyashi, Miwa; Dulchinos, Victoria

    2012-01-01

    Human factors data collected during the SARDA HITL Simulation Experiment include a variety of subjective measures, including the NASA TLX, questionnaire questions regarding situational awareness, advisory usefulness, UI usability, and controller trust. Preliminary analysis of the TLX data indicate that workload may not be adversely affected by use of the advisories, additionally, the controller's subjective ratings of the advisories may suggest acceptance of the tool.

  14. Nursing performance under high workload: a diary study on the moderating role of selection, optimization and compensation strategies.

    Science.gov (United States)

    Baethge, Anja; Müller, Andreas; Rigotti, Thomas

    2016-03-01

    The aim of this study was to investigate whether selective optimization with compensation constitutes an individualized action strategy for nurses wanting to maintain job performance under high workload. High workload is a major threat to healthcare quality and performance. Selective optimization with compensation is considered to enhance the efficient use of intra-individual resources and, therefore, is expected to act as a buffer against the negative effects of high workload. The study applied a diary design. Over five consecutive workday shifts, self-report data on workload was collected at three randomized occasions during each shift. Self-reported job performance was assessed in the evening. Self-reported selective optimization with compensation was assessed prior to the diary reporting. Data were collected in 2010. Overall, 136 nurses from 10 German hospitals participated. Selective optimization with compensation was assessed with a nine-item scale that was specifically developed for nursing. The NASA-TLX scale indicating the pace of task accomplishment was used to measure workload. Job performance was assessed with one item each concerning performance quality and forgetting of intentions. There was a weaker negative association between workload and both indicators of job performance in nurses with a high level of selective optimization with compensation, compared with nurses with a low level. Considering the separate strategies, selection and compensation turned out to be effective. The use of selective optimization with compensation is conducive to nurses' job performance under high workload levels. This finding is in line with calls to empower nurses' individual decision-making. © 2015 John Wiley & Sons Ltd.

  15. Influence of academic examination stress on hematological measurements in subjectively healthy volunteers.

    Science.gov (United States)

    Maes, M; Van Der Planken, M; Van Gastel, A; Bruyland, K; Van Hunsel, F; Neels, H; Hendriks, D; Wauters, A; Demedts, P; Janca, A; Scharpé, S

    1998-09-21

    Some recent reports showed that a brief exposure to a mental stressor during 3-20 min may induce hematological changes in humans. The aim of the present study was to examine the effects of academic examination stress on erythron variables, such as the number of red blood cells (RBC), hemoglobin (Hb), hematocrit (Ht), mean corpuscular volume (MCV), mean cell Hb (MCH), mean cell Hb concentration (MCHC), RBC distribution width (RDW), and serum iron and transferrin (Tf). The above variables were determined in 41 students in three conditions, i.e. the stress condition (the day before a difficult oral exam) and two baseline conditions, i.e. a few weeks earlier and later. At the same occasions, subjects completed the Perceived Stress Scale (PSS), the state version of the State-Trait Anxiety Inventory (STAI) and the Profile of Mood States (POMS). Academic examination stress significantly increased Ht, Hb, MCV, MCH and MCHC and significantly decreased RDW. There were significant relationships between the stress-induced changes in the PSS, STAI and POMS scores and those in Ht, Hb, MCV and MCH (allpositive) and RDW (negative). It is concluded that academic examination stress induces significant hematological changes indicative of an increased number of large RBC and increased hemoglobinisation, which cannot be explained by shifts of fluid out of the intravascular space, concentrating non-diffusible blood constituents.

  16. Degradation data analysis based on a generalized Wiener process subject to measurement error

    Science.gov (United States)

    Li, Junxing; Wang, Zhihua; Zhang, Yongbo; Fu, Huimin; Liu, Chengrui; Krishnaswamy, Sridhar

    2017-09-01

    Wiener processes have received considerable attention in degradation modeling over the last two decades. In this paper, we propose a generalized Wiener process degradation model that takes unit-to-unit variation, time-correlated structure and measurement error into considerations simultaneously. The constructed methodology subsumes a series of models studied in the literature as limiting cases. A simple method is given to determine the transformed time scale forms of the Wiener process degradation model. Then model parameters can be estimated based on a maximum likelihood estimation (MLE) method. The cumulative distribution function (CDF) and the probability distribution function (PDF) of the Wiener process with measurement errors are given based on the concept of the first hitting time (FHT). The percentiles of performance degradation (PD) and failure time distribution (FTD) are also obtained. Finally, a comprehensive simulation study is accomplished to demonstrate the necessity of incorporating measurement errors in the degradation model and the efficiency of the proposed model. Two illustrative real applications involving the degradation of carbon-film resistors and the wear of sliding metal are given. The comparative results show that the constructed approach can derive a reasonable result and an enhanced inference precision.

  17. An experiential thinking style: its facets and relations with objective and subjective criterion measures.

    Science.gov (United States)

    Norris, Paul; Epstein, Seymour

    2011-10-01

    In Study 1, an experiential factor divided into the following 3 factors when 3 or more factors were extracted: intuition, emotionality, and imagination; whereas a rational factor retained its coherence. In Study 2, an experiential but not a rational thinking style was positively associated with performance measures of creativity, humor, aesthetic judgment, and intuition and with self-report measures of empathy and social popularity. A rational thinking style was associated with several measures of adjustment. Both thinking styles were positively related to personal growth. Support was provided from several sources for the discriminant validity of the experiential facets. In a third study, the independence of the 2 thinking styles and of gender differences in self-reported data were verified by observations by others of participants' thinking styles. The importance of identifying facets of an experiential thinking style and of discovering previously unrecognized favorable attributes of this thinking style was discussed. © 2011 The Authors. Journal of Personality © 2011, Wiley Periodicals, Inc.

  18. A History of In Vivo Neutron Activation Analysis in Measurement of Aluminum in Human Subjects.

    Science.gov (United States)

    Mohseni, Hedieh K; Chettle, David R

    2016-01-01

    Aluminum, as an abundant metal, has gained widespread use in human life, entering the body predominantly as an additive to various foods and drinking water. Other major sources of exposure to aluminum include medical, cosmetic, and occupational routes. As a common environmental toxin, with well-known roles in several medical conditions such as dialysis encephalopathy, aluminum is considered a potential candidate in the causality of Alzheimer's disease. Aluminum mostly accumulates in the bone, which makes bone an indicator of the body burden of aluminum and an ideal organ as a proxy for the brain. Most of the techniques developed for measuring aluminum include bone biopsy, which requires invasive measures, causing inconvenience for the patients. There has been a considerable effort in developing non-invasive approaches, which allow for monitoring aluminum levels for medical and occupational purposes in larger populations. In vivo neutron activation analysis, a method based on nuclear activation of isotopes of elements in the body and their subsequent detection, has proven to be an invaluable tool for this purpose. There are definite challenges in developing in vivo non-invasive techniques capable of detecting low levels of aluminum in healthy individuals and aluminum-exposed populations. The following review examines the method of in vivo neutron activation analysis in the context of aluminum measurement in humans focusing on different neutron sources, interference from other activation products, and the improvements made in minimum detectable limits and patient dose over the past few decades.

  19. Subjective reports versus objective measurement of sleep latency and sleep duration in pregnancy.

    Science.gov (United States)

    Wilson, Danielle L; Fung, Alison; Walker, Susan P; Barnes, Maree

    2013-01-01

    This study compared self-reported sleep latency (SL) and total sleep time (TST) to objective measures on polysomnography (PSG) during pregnancy. Thirty-three women in the third trimester (T3) of pregnancy, 16 women in the first trimester (T1) of pregnancy, and 15 non-pregnant women underwent overnight PSG, and shortly after awakening reported their perceived SL and TST. Results showed that, on average, the T3 group slightly overestimated their TSTs, whereas the T1 and non-pregnant groups underestimated TSTs when compared with objective measurement. All groups overestimated SL, and perceived SL was closest to the first epoch of 10 min of uninterrupted sleep or the first epoch of slow-wave sleep, rather than the first epoch of sleep (the current definition used for diagnostic sleep studies). The wide variation in discrepancies between estimation and PSG measurement for both TST and SL shows that self-reports made by both pregnant and non-pregnant women tend to be unreliable, which has important implications both clinically and for the many studies based on self-reported sleep patterns in pregnancy.

  20. Effect of system workload on operating system reliability - A study on IBM 3081

    Science.gov (United States)

    Iyer, R. K.; Rossetti, D. J.

    1985-01-01

    This paper presents an analysis of operating system failures on an IBM 3081 running VM/SP. Three broad categories of software failures are found: error handling, program control or logic, and hardware related; it is found that more than 25 percent of software failures occur in the hardware/software interface. Measurements show that results on software reliability cannot be considered representative unless the system workload is taken into account. The overall CPU execution rate, although measured to be close to 100 percent most of the time, is not found to correlate strongly with the occurrence of failures. Possible reasons for the observed workload failure dependency, based on detailed investigations of the failure data, are discussed.

  1. Synthesis of workload reduction strategies for construction inspection.

    Science.gov (United States)

    2008-10-01

    State departments of transportation (DOTs) have seen significant funding increases throughout the past decade. The : additional funding has also brought about an increase in the construction inspection and testing workload, but the : DOTs have not se...

  2. Eye Tracking Metrics for Workload Estimation in Flight Deck Operation

    Science.gov (United States)

    Ellis, Kyle; Schnell, Thomas

    2010-01-01

    Flight decks of the future are being enhanced through improved avionics that adapt to both aircraft and operator state. Eye tracking allows for non-invasive analysis of pilot eye movements, from which a set of metrics can be derived to effectively and reliably characterize workload. This research identifies eye tracking metrics that correlate to aircraft automation conditions, and identifies the correlation of pilot workload to the same automation conditions. Saccade length was used as an indirect index of pilot workload: Pilots in the fully automated condition were observed to have on average, larger saccadic movements in contrast to the guidance and manual flight conditions. The data set itself also provides a general model of human eye movement behavior and so ostensibly visual attention distribution in the cockpit for approach to land tasks with various levels of automation, by means of the same metrics used for workload algorithm development.

  3. [Technological innovation and healthcare professionals' workloads: an ambiguous relationship].

    Science.gov (United States)

    de Pires, Denise Elvira Pires; Bertoncini, Judite Hennemann; Trindade, Letícia de Lima; Matos, Eliane; Azambuja, Eliana; Borges, Ana Maria Fernandes

    2012-03-01

    This is an integrative review with the aim of tracing the scientific production concerning the influence of technological innovation in health care professionals' workloads. Fifty-seven (57) publications presented from 2004 to 2009 were selected from the LILACS and PubMed databases. In the selected studies field research using qualitative approaches and carried out in hospitals predominated. No study had the purpose to analyze the relationship between technological innovation and workloads. In studies involving technological innovation, publications concerning information and communication technologies and new forms of work organizations were highlighted studies concerning conditions which promote stress and Burnout predominated in the workloads theme. Results show an ambiguous relationship between technological innovation and workloads, which are either increased or diminished by innovations.

  4. Wealth, justice and freedom: Objective and subjective measures predicting poor mental health in a study across eight countries

    OpenAIRE

    Saskia Scholten; Julia Velten; Torsten Neher; Jürgen Margraf

    2017-01-01

    Background: Macro-level factors (MF) such as wealth, justice and freedom measured with objective country-level indicators (objective MF), for instance the Gross Domestic Product (GDP), have been investigated in relation to health and well-being, but rarely in connection with depression, anxiety and stress subsumed as poor mental health. Also, a combination of different objective MF and of how individuals perceive those MF (subjective MF) has not been taken into consideration. In the present s...

  5. Wealth, justice and freedom: Objective and subjective measures predicting poor mental health in a study across eight countries

    OpenAIRE

    Scholten, Saskia; Velten, Julia; Neher, Torsten; Margraf, Jürgen

    2017-01-01

    Background Macro-level factors (MF) such as wealth, justice and freedom measured with objective country-level indicators (objective MF), for instance the Gross Domestic Product (GDP), have been investigated in relation to health and well-being, but rarely in connection with depression, anxiety and stress subsumed as poor mental health. Also, a combination of different objective MF and of how individuals perceive those MF (subjective MF) has not been taken into consideration. In the present st...

  6. Fatigue in Emergency Services Operations: Assessment of the Optimal Objective and Subjective Measures Using a Simulated Wildfire Deployment

    Directory of Open Access Journals (Sweden)

    Sally A. Ferguson

    2016-01-01

    Full Text Available Under controlled laboratory conditions, neurobehavioral assays such as the Psychomotor Vigilance Task (PVT are sensitive to increasing levels of fatigue, and in general, tend to correlate with subjective ratings. However, laboratory studies specifically curtail physical activity, potentially limiting the applicability of such findings to field settings that involve physical work. In addition, laboratory studies typically involve healthy young male participants that are not always representative of a typical working population. In order to determine whether these findings extend to field-like conditions, we put 88 Australian volunteer firefighters through a multi-day firefighting simulation. Participants were required to perform real-world physical and cognitive tasks under conditions of elevated temperature and moderate sleep restriction. We aimed to examine changes in fatigue in an effort to determine the optimum objective and subjective measures. Objective and subjective tests were sensitive to fatigue outside laboratory conditions. The PVT was the most sensitive assay of objective fatigue, with the Samn-Perelli fatigue scale the most sensitive of the subjective measures. The Samn-Perilli fatigue scale correlated best with PVT performance, but explained a small amount of variance. Although the Samn-Perelli scale can be easily administered in the field, the wide range of individual variance limits its efficacy as a once-off assessment tool. Rather, fatigue measures should be applied as a component of a broader fatigue risk management system. Findings provide firefighting agencies, and other occupations involving physical work, guidance as to the most sensitive and specific measures for assessing fatigue in their personnel.

  7. Objectively measured sedentary behaviour and moderate and vigorous physical activity in different school subjects: a cross-sectional study

    OpenAIRE

    Mooses, Kerli; M?gi, Katrin; Riso, Eva-Maria; Kalma, Maarja; Kaasik, Priit; Kull, Merike

    2017-01-01

    Background Evidence shows the positive influence of moderate and vigorous physical activity (MVPA) and negative influence of sedentary time on health and academic achievement. Although schools can significantly contribute to overall physical activity, little is known about MVPA and sedentary behaviour in different school subjects in different grades. Methods Physical activity of 646 students from 18 schools (94 classes) and from three school stages (grades 1?9, aged 7?16) was measured with ac...

  8. Objectively measured sedentary behaviour and moderate and vigorous physical activity in different school subjects: a cross-sectional study

    OpenAIRE

    Kerli Mooses; Katrin Mägi; Eva-Maria Riso; Maarja Kalma; Priit Kaasik; Merike Kull

    2017-01-01

    Abstract Background Evidence shows the positive influence of moderate and vigorous physical activity (MVPA) and negative influence of sedentary time on health and academic achievement. Although schools can significantly contribute to overall physical activity, little is known about MVPA and sedentary behaviour in different school subjects in different grades. Methods Physical activity of 646 students from 18 schools (94 classes) and from three school stages (grades 1–9, aged 7–16) was measure...

  9. GPs' perceptions of workload in England: a qualitative interview study.

    Science.gov (United States)

    Croxson, Caroline Hd; Ashdown, Helen F; Hobbs, Fd Richard

    2017-02-01

    GPs report the lowest levels of morale among doctors, job satisfaction is low, and the GP workforce is diminishing. Workload is frequently cited as negatively impacting on commitment to a career in general practice, and many GPs report that their workload is unmanageable. To gather an in-depth understanding of GPs' perceptions and attitudes towards workload. All GPs working within NHS England were eligible. Advertisements were circulated via regional GP e-mail lists and national social media networks in June 2015. Of those GPs who responded, a maximum-variation sample was selected until data saturation was reached. Semi-structured, qualitative interviews were conducted. Data were analysed thematically. In total, 171 GPs responded, and 34 were included in this study. GPs described an increase in workload over recent years, with current working days being long and intense, raising concerns over the wellbeing of GPs and patients. Full-time partnership was generally not considered to be possible, and many participants felt workload was unsustainable, particularly given the diminishing workforce. Four major themes emerged to explain increased workload: increased patient needs and expectations; a changing relationship between primary and secondary care; bureaucracy and resources; and the balance of workload within a practice. Continuity of care was perceived as being eroded by changes in contracts and working patterns to deal with workload. This study highlights the urgent need to address perceived lack of investment and clinical capacity in general practice, and suggests that managing patient expectations around what primary care can deliver, and reducing bureaucracy, have become key issues, at least until capacity issues are resolved. © British Journal of General Practice 2017.

  10. Register of Research in Progress on Mental Workload.

    Science.gov (United States)

    1982-07-01

    are translated into equipment design and training solutions. The Register of Research in Progress on Mental Workload was conceived as one means by which...as a test bed for the workload assessment program. The validity of this aproach will be assessed with a series of simulation experiments in our GAT-I...Discrete mental tasks are used, ranging from search tasks to sentence comprehension tasks to language translation tasks (simultaneous interpretation

  11. Measuring Treatment Outcomes in Comorbid Insomnia and Fibromyalgia: Concordance of Subjective and Objective Assessments.

    Science.gov (United States)

    Mundt, Jennifer M; Crew, Earl C; Krietsch, Kendra; Roth, Alicia J; Vatthauer, Karlyn; Robinson, Michael E; Staud, Roland; Berry, Richard B; McCrae, Christina S

    2016-02-01

    In insomnia, actigraphy tends to underestimate wake time compared to diaries and PSG. When chronic pain co-occurs with insomnia, sleep may be more fragmented, including more movement and arousals. However, individuals may not be consciously aware of these arousals. We examined the baseline concordance of diaries, actigraphy, and PSG as well as the ability of each assessment method to detect changes in sleep following cognitive behavioral therapy for insomnia (CBT-I). Adults with insomnia and fibromyalgia (n = 113) were randomized to CBT-I, CBT for pain, or waitlist control. At baseline and posttreatment, participants completed one night of PSG and two weeks of diaries/actigraphy. At baseline, objective measures estimated lower SOL, higher TST, and higher SE than diaries (ps treatment-related changes. PSG values did not change significantly for any sleep parameters. However, diaries showed improvements in SOL, WASO, and SE, and actigraphy also detected the WASO and SE improvements (ps insomnia. However, actigraphy showed greater sensitivity to treatment-related changes than PSG; PSG failed to detect any improvements, but actigraphy demonstrated changes in WASO and SE, which were also found with diaries. In comorbid insomnia/fibromyalgia, actigraphy may therefore have utility in measuring treatment outcomes. © 2015 American Academy of Sleep Medicine.

  12. Examining the Convergent and Discriminant Validity of Visual and Mental Workload Using Ocular Activity Variables

    Science.gov (United States)

    2010-03-01

    Measure of Mental Workload Previous research has linked fixations to information processing (Salthouse, Ellis, Diener , & Somberg, 1981), but few...Operating at the Sharp End: The Complexity of Human Error. In M. S. Bogner ( Ed .), Human error in medicine (pp. 255–301). Hillsdale, NJ: Erlbaum (1994...Decision Making Under Time Pressure. In O. Svenson & J. Maule ( Eds .). Time pressure and stress in human judgment and decision making. (pp. 27– 40). New

  13. Event-related brain potentials as indices of mental workload and attentional allocation

    Science.gov (United States)

    Kramer, Arthur F.; Donchin, Emanuel; Wickens, Christopher D.

    1988-01-01

    Over the past decade considerable strides were made in explicating the antecedant conditions necessary for the elicitation, and the modulation of the amplitude and latency, of a number of components of the event-related brain potential (ERP). The focus of this report is on P300. The degree to which the psychophysiological measures contribute to issues in two real-world domains (communication devices for the motor impaired and the assessment of mental workload of aircraft pilots) are examined.

  14. Physical and mental workloads in professional dance teachers.

    Science.gov (United States)

    Wanke, Eileen M; Schmidt, Mike; Leslie-Spinks, Jeremy; Fischer, Axel; Groneberg, David A

    2015-03-01

    The aim of this cross-sectional study was to investigate the level of mental and physical workloads in professional dance teachers depending on the trained students' age, technique level, or dance style. A total number of 133 professional dance pedagogues responded to an online cross-sectional questionnaire survey on self-assessment of physical and mental workloads occurring during dance units. The majority of dance teachers estimated their level of physical and mental workload to be almost as high as that of their students, with differences in physical and mental workloads observed depending on dance style, age of students, and technical level. More than 60% of the teachers were convinced that their occupation implies positive effects on their own health in terms of self-realization (78.2%), musculoskeletal system (66.9%), and social relationships (61.7%). Of all respondents, 58.6% stated that their musculoskeletal system was jeopardized by the physically demanding activity. This is followed by the fear of financial insecurity (50.4%). The majority of all dance teachers (males 65.4%, females 63.9%) would like to obtain further education on prevention against or dealing with physical workload. Physical and mental workloads play an important role in dance teaching. Coping with or preventing these loads could be keys to a lifelong, healthy career as a professional dance teacher. Future trials should look at clinical parameters of physical and mental load.

  15. Food Addiction: definition, measurement and prevalence in healthy subjects and in patients with eating disorders.

    Science.gov (United States)

    Imperatori, Claudio; Fabbricatore, Mariantonietta; Vumbaca, Viviana; Innamorati, Marco; Contardi, Anna; Farina, Benedetto

    2016-01-01

    The construct of “Food Addiction” (FA) has been introduced in the last decades to better understand abnormal eating patterns in obese and overweight people and in patients with Eating Disorders (EDs). Despite a substantial parallelism between drug addiction and FA, there is still no agreement in considering FA an independent ED or a useful convincing concept. Therefore, the purpose of this review is to aggregate available data, in order to increase knowledge about: 1) definition, measurement and general features of FA; 2) prevalence of FA in clinical and non-clinical samples. Available data suggest that FA seems to be a transnosografic construct and exists in all EDs, with higher prevalence in Bulimia Nervosa. Although the discussion on the autonomous diagnosis of FA within EDs remains open, studies have reported that comorbidity between FA and other EDs is associated with worse clinical conditions and symptoms, justifying, as a result, the usefulness of assessing and treating this condition.

  16. Effector cell mediated cytotoxicity measured by intracellular Granzyme B release in HIV infected subjects

    Directory of Open Access Journals (Sweden)

    Mahajan Supriya D.

    2003-01-01

    Full Text Available CD8+ cytotoxic T lymphocyte (CTL activity is currently believed to be one of the key immunologic mechanisms responsible for the prevention or attenuation of HIV-1 infection. The induction of CD8+ T cell activation may also result in the production of soluble or non-classical lytic factors that are associated with protection from infection or slower disease progression. Traditionally, CD8+ CTL responses have been measured by the classic chromium release assay, monitoring the ability of T cells (Effector cells to lyse radiolabelled HLA – matched “target cells” that express the appropriate antigen-MHC complex. This method is not only labor intensive, semi quantitative assay at best, but also needs fresh, non-cryopreserved cells. Recently, cytokine specific ELISPOT assays or tetrameric MHC-I/ peptide complexes have utilized to directly quantitate circulating CD8+ effector cells, and these assays are more sensitive, quantitative and reproducible than the traditional CTL lysis assay and can also be performed on cryopreserved cells. Although these are reproducible assays for the assessment of soluble antiviral activity secreted by activated T cell populations they can be extremely expensive to perform. We have used FACS Analysis to measure Granzyme B release as a function of cell mediated cytotoxicity. This method helps quantitate the CTL activity and also identifies the phenotype of the cells elucidating this immune response. The method described not only monitors immunological response but also is also simple to perform, precise and extremely time efficient and is ideal for screening a large number of samples.

  17. Predicting workload profiles of brain-robot interface and electromygraphic neurofeedback with cortical resting-state networks: personal trait or task-specific challenge?

    Science.gov (United States)

    Fels, Meike; Bauer, Robert; Gharabaghi, Alireza

    2015-08-01

    Objective. Novel rehabilitation strategies apply robot-assisted exercises and neurofeedback tasks to facilitate intensive motor training. We aimed to disentangle task-specific and subject-related contributions to the perceived workload of these interventions and the related cortical activation patterns. Approach. We assessed the perceived workload with the NASA Task Load Index in twenty-one subjects who were exposed to two different feedback tasks in a cross-over design: (i) brain-robot interface (BRI) with haptic/proprioceptive feedback of sensorimotor oscillations related to motor imagery, and (ii) control of neuromuscular activity with feedback of the electromyography (EMG) of the same hand. We also used electroencephalography to examine the cortical activation patterns beforehand in resting state and during the training session of each task. Main results. The workload profile of BRI feedback differed from EMG feedback and was particularly characterized by the experience of frustration. The frustration level was highly correlated across tasks, suggesting subject-related relevance of this workload component. Those subjects who were specifically challenged by the respective tasks could be detected by an interhemispheric alpha-band network in resting state before the training and by their sensorimotor theta-band activation pattern during the exercise. Significance. Neurophysiological profiles in resting state and during the exercise may provide task-independent workload markers for monitoring and matching participants’ ability and task difficulty of neurofeedback interventions.

  18. Effect of different training workload on overhead throwing performance with different weighted balls.

    Science.gov (United States)

    van den Tillaar, Roland; Marques, Mário C

    2013-05-01

    The purpose of this study was to investigate the effect of a single and a double training workload with 3-kg medicine ball on the throwing speed in 2-handed overhead throwing movement. Second, what the effect of training with 3-kg medicine balls had on throwing speed with other ball weights. Forty high school students (age 15.9 ± 1.0 year, mass 60.9 ± 9 kg, height 1.68 ± 0.08 m), divided into 3 speed-matched groups, participated in the study. The first group was a control group and did not train any throwing program regimen, whereas the other 2 groups trained overhead throwing with a single (3 series of 6 throws with a 3-kg medicine ball) or double training workload (6 series of 6 throws with a 3-kg medicine ball) for 6 weeks. Throwing speed with 0.35-, 0.45-, 1-, and 3-kg medicine balls was tested before and after a training period of 6 weeks with 2 sessions per week. A significant (p ≤ 0.05) increase in throwing speed was found after the 6-week training period with the 0.35- (5.1%), 1- (3.5%), and 3-kg medicine balls (5.2%) for both training groups, but not with the 0.45-kg ball (0.6%). This increase was mainly caused by the increase of the double workload group. This indicates that training workload is of importance in these subjects for enhancement of ball throwing performance and in designing training programs. Furthermore, that throwing with high enough training volume of throws with a 3-kg medicine ball also can increase ball speed with lighter balls.

  19. Effect of inspiration on airway dimensions measured in maximal inspiration CT images of subjects without airflow limitation

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Jens; Raket, Lars Lau; Nielsen, Mads [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Wille, Mathilde M.W.; Dirksen, Asger [University of Copenhagen, Department of Respiratory Medicine, Gentofte Hospital, Hellerup (Denmark); Feragen, Aasa [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Max Planck Institute for Intelligent Systems and Max Planck Institute for Developmental Biology, Tuebingen (Germany); Pedersen, Jesper H. [Rigshospitalet, University Hospital of Copenhagen, Department of Cardio-Thoracic Surgery RT, Copenhagen (Denmark); Bruijne, Marleen de [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Erasmus MC Rotterdam, Departments of Medical Informatics and Radiology, Rotterdam (Netherlands)

    2014-09-15

    To study the effect of inspiration on airway dimensions measured in voluntary inspiration breath-hold examinations. 961 subjects with normal spirometry were selected from the Danish Lung Cancer Screening Trial. Subjects were examined annually for five years with low-dose CT. Automated software was utilized to segment lungs and airways, identify segmental bronchi, and match airway branches in all images of the same subject. Inspiration level was defined as segmented total lung volume (TLV) divided by predicted total lung capacity (pTLC). Mixed-effects models were used to predict relative change in lumen diameter (ALD) and wall thickness (AWT) in airways of generation 0 (trachea) to 7 and segmental bronchi (R1-R10 and L1-L10) from relative changes in inspiration level. Relative changes in ALD were related to relative changes in TLV/pTLC, and this distensibility increased with generation (p < 0.001). Relative changes in AWT were inversely related to relative changes in TLV/pTLC in generation 3-7 (p < 0.001). Segmental bronchi were widely dispersed in terms of ALD (5.7 ± 0.7 mm), AWT (0.86 ± 0.07 mm), and distensibility (23.5 ± 7.7 %). Subjects who inspire more deeply prior to imaging have larger ALD and smaller AWT. This effect is more pronounced in higher-generation airways. Therefore, adjustment of inspiration level is necessary to accurately assess airway dimensions. (orig.)

  20. Observer Design for One-Sided Lipschitz Nonlinear Systems Subject to Measurement Delays

    Directory of Open Access Journals (Sweden)

    Sohaira Ahmad

    2015-01-01

    Full Text Available This paper presents a novel nonlinear observer-design approach to one-sided Lipschitz nonlinear systems in the presence of output delays. The crux of the approach is to overcome the practical consequences of time delays, encountered due to distant sensor position and time lag in measurement, for estimation of physical and engineering nonlinear system states. A Lyapunov-Krasovskii functional is employed, the time derivative of which is solved using Jensen’s inequality, one-sided Lipschitz condition, and quadratic inner-boundedness, and, accordingly, design conditions for delay-range-dependent nonlinear observer for delayed one-sided Lipschitz systems are derived. Further, novel solutions to the problems of delay-dependent observer synthesis of one-sided Lipschitz models and delay-range-dependent state estimation of linear and Lipschitz nonlinear systems are deduced from the present delay-range-dependent technique. An observer formulation methodology for retrieval of one-sided Lipschitz nonlinear-system states, which is robust against L2 norm-bounded perturbations, is devised. The resultant design conditions, in contrast to the conventional procedures, can be solved via less conservative linear matrix inequality- (LMI- based routines that succeed by virtue of additional LMI variables, meaningful transformations, and cone complementary linearization algorithm. Numerical examples are worked out to illustrate the effectiveness of the proposed observer-synthesis approach for delayed one-sided Lipschitz systems.

  1. Analysis of Subjects' Vulnerability in a Touch Screen Game Using Behavioral Metrics.

    Science.gov (United States)

    Parsinejad, Payam; Sipahi, Rifat

    2017-12-01

    In this article, we report results on an experimental study conducted with volunteer subjects playing a touch-screen game with two unique difficulty levels. Subjects have knowledge about the rules of both game levels, but only sufficient playing experience with the easy level of the game, making them vulnerable with the difficult level. Several behavioral metrics associated with subjects' playing the game are studied in order to assess subjects' mental-workload changes induced by their vulnerability. Specifically, these metrics are calculated based on subjects' finger kinematics and decision making times, which are then compared with baseline metrics, namely, performance metrics pertaining to how well the game is played and a physiological metric called pnn50 extracted from heart rate measurements. In balanced experiments and supported by comparisons with baseline metrics, it is found that some of the studied behavioral metrics have the potential to be used to infer subjects' mental workload changes through different levels of the game. These metrics, which are decoupled from task specifics, relate to subjects' ability to develop strategies to play the game, and hence have the advantage of offering insight into subjects' task-load and vulnerability assessment across various experimental settings.

  2. Accumulated workloads and the acute:chronic workload ratio relate to injury risk in elite youth football players.

    Science.gov (United States)

    Bowen, Laura; Gross, Aleksander Stefan; Gimpel, Mo; Li, François-Xavier

    2017-03-01

    The purpose of this study was to investigate the relationship between physical workload and injury risk in elite youth football players. The workload data and injury incidence of 32 players were monitored throughout 2 seasons. Multiple regression was used to compare cumulative (1, 2, 3 and 4-weekly) loads and acute:chronic (A:C) workload ratios (acute workload divided by chronic workload) between injured and non-injured players for specific GPS and accelerometer-derived variables:total distance (TD), high-speed distance (HSD), accelerations (ACC) and total load. Workloads were classified into discrete ranges by z-scores and the relative risk was determined. A very high number of ACC (≥9254) over 3 weeks was associated with the highest significant overall (relative risk (RR)=3.84) and non-contact injury risk (RR=5.11). Non-contact injury risk was significantly increased when a high acute HSD was combined with low chronic HSD (RR=2.55), but not with high chronic HSD (RR=0.47). Contact injury risk was greatest when A:C TD and ACC ratios were very high (1.76 and 1.77, respectively) (RR=4.98). In general, higher accumulated and acute workloads were associated with a greater injury risk. However, progressive increases in chronic workload may develop the players' physical tolerance to higher acute loads and resilience to injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. Subject-enabled analytics model on measurement statistics in health risk expert system for public health informatics.

    Science.gov (United States)

    Chung, Chi-Jung; Kuo, Yu-Chen; Hsieh, Yun-Yu; Li, Tsai-Chung; Lin, Cheng-Chieh; Liang, Wen-Miin; Liao, Li-Na; Li, Chia-Ing; Lin, Hsueh-Chun

    2017-11-01

    This study applied open source technology to establish a subject-enabled analytics model that can enhance measurement statistics of case studies with the public health data in cloud computing. The infrastructure of the proposed model comprises three domains: 1) the health measurement data warehouse (HMDW) for the case study repository, 2) the self-developed modules of online health risk information statistics (HRIStat) for cloud computing, and 3) the prototype of a Web-based process automation system in statistics (PASIS) for the health risk assessment of case studies with subject-enabled evaluation. The system design employed freeware including Java applications, MySQL, and R packages to drive a health risk expert system (HRES). In the design, the HRIStat modules enforce the typical analytics methods for biomedical statistics, and the PASIS interfaces enable process automation of the HRES for cloud computing. The Web-based model supports both modes, step-by-step analysis and auto-computing process, respectively for preliminary evaluation and real time computation. The proposed model was evaluated by computing prior researches in relation to the epidemiological measurement of diseases that were caused by either heavy metal exposures in the environment or clinical complications in hospital. The simulation validity was approved by the commercial statistics software. The model was installed in a stand-alone computer and in a cloud-server workstation to verify computing performance for a data amount of more than 230K sets. Both setups reached efficiency of about 105 sets per second. The Web-based PASIS interface can be used for cloud computing, and the HRIStat module can be flexibly expanded with advanced subjects for measurement statistics. The analytics procedure of the HRES prototype is capable of providing assessment criteria prior to estimating the potential risk to public health. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Comparison of optic area measurement using fundus photography and optical coherence tomography between optic nerve head drusen and control subjects.

    Science.gov (United States)

    Flores-Rodríguez, Patricia; Gili, Pablo; Martín-Ríos, María Dolores; Grifol-Clar, Eulalia

    2013-03-01

    To compare optic disc area measurement between optic nerve head drusen (ONHD) and control subjects using fundus photography, time-domain optical coherence tomography (TD-OCT) and spectral-domain optical coherence tomography (SD-OCT). We also made a comparison between each of the three techniques. We performed our study on 66 eyes (66 patients) with ONHD and 70 healthy control subjects (70 controls) with colour ocular fundus photography at 20º (Zeiss FF 450 IR plus), TD-OCT (Stratus OCT) with the Fast Optic Disc protocol and SD-OCT (Cirrus OCT) with the Optic Disc Cube 200 × 200 protocol for measurement of the optic disc area. The measurements were made by two observers and in each measurement a correction of the image magnification factor was performed. Measurement comparison using the Student's t-test/Mann-Whitney U test, the intraclass correlation coefficient, Pearson/Spearman rank correlation coefficient and the Bland-Altman plot was performed in the statistical analysis. Mean and standard deviation (SD) of the optic disc area in ONHD and in controls was 2.38 (0.54) mm(2) and 2.54 (0.42) mm(2), respectively with fundus photography; 2.01 (0.56) mm(2) and 1.66 (0.37) mm(2), respectively with TD-OCT, and 2.03 (0.49) mm(2) and 1.75 (0.38) mm(2), respectively with SD-OCT. In ONHD and controls, repeatability of optic disc area measurement was excellent with fundus photography and optical coherence tomography (TD-OCT and SD-OCT), but with a low degree of agreement between both techniques. Optic disc area measurement is smaller in ONHD compared to healthy subjects with fundus photography, unlike time-domain and spectral-domain optical coherence tomography in which the reverse is true. Both techniques offer good repeatability, but a low degree of correlation and agreement, which means that optic disc area measurement is not interchangeable or comparable between techniques. Ophthalmic & Physiological Optics © 2013 The College of Optometrists.

  5. Creation and validation of an instrument to identify nursing activities in pediatric wards: information for determining workload

    Directory of Open Access Journals (Sweden)

    Nanci Cristiano Santos

    2013-10-01

    Full Text Available The aim of this study was to develop and validate an instrument for identifying nursing activities performed in a pediatric ward and to provide a basis for defining the workload of these units. The instrument was developed by selecting the activities relevant to pediatric nursing from the Nursing Intervention Classification and then submitting them to a panel of judges for validation. The panel considered the selected activities relevant and representative of pediatric nursing practice. Now that representative activities for the nursing workload have been identified, we envision new studies to verify their usefulness in practice. Determining the amount of time each activity takes to perform will help to develop a system for measuring the workloads of nursing teams in pediatric wards.

  6. Analysis of misclassified correlated binary data using a multivariate probit model when covariates are subject to measurement error.

    Science.gov (United States)

    Roy, Surupa; Banerjee, Tathagata

    2009-06-01

    A multivariate probit model for correlated binary responses given the predictors of interest has been considered. Some of the responses are subject to classification errors and hence are not directly observable. Also measurements on some of the predictors are not available; instead the measurements on its surrogate are available. However, the conditional distribution of the unobservable predictors given the surrogate is completely specified. Models are proposed taking into account either or both of these sources of errors. Likelihood-based methodologies are proposed to fit these models. To ascertain the effect of ignoring classification errors and/or measurement error on the estimates of the regression and correlation parameters, a sensitivity study is carried out through simulation. Finally, the proposed methodology is illustrated through an example.

  7. Subjective Cognitive Decline in Older Adults: An Overview of Self-Report Measures Used Across 19 International Research Studies

    Science.gov (United States)

    Rabin, Laura A.; Smart, Colette M.; Crane, Paul K.; Amariglio, Rebecca E.; Berman, Lorin M.; Boada, Mercè; Buckley, Rachel F.; Chételat, Gaël; Dubois, Bruno; Ellis, Kathryn A.; Gifford, Katherine A.; Jefferson, Angela L.; Jessen, Frank; Katz, Mindy J.; Lipton, Richard B.; Luck, Tobias; Maruff, Paul; Mielke, Michelle M.; Molinuevo, José Luis; Naeem, Farnia; Perrotin, Audrey; Petersen, Ronald C.; Rami, Lorena; Reisberg, Barry; Rentz, Dorene M.; Riedel-Heller, Steffi G.; Risacher, Shannon L.; Rodriguez, Octavio; Sachdev, Perminder S.; Saykin, Andrew J.; Slavin, Melissa J.; Snitz, Beth E.; Sperling, Reisa A.; Tandetnik, Caroline; van der Flier, Wiesje M.; Wagner, Michael; Wolfsgruber, Steffen; Sikkes, Sietske A.M.

    2015-01-01

    Research increasingly suggests that subjective cognitive decline (SCD) in older adults, in the absence of objective cognitive dysfunction or depression, may be a harbinger of non-normative cognitive decline and eventual progression to dementia. Little is known, however, about the key features of self-report measures currently used to assess SCD. The Subjective Cognitive Decline Initiative (SCD-I) Working Group is an international consortium established to develop a conceptual framework and research criteria for SCD (Jessen et al., 2014, Alzheimers Dement 10, 844–852). In the current study we systematically compared cognitive self-report items used by 19 SCD-I Working Group studies, representing 8 countries and 5 languages. We identified 34 self-report measures comprising 640 cognitive self-report items. There was little overlap among measures—approximately 75% of measures were used by only one study. Wide variation existed in response options and item content. Items pertaining to the memory domain predominated, accounting for about 60% of items surveyed, followed by executive function and attention, with 16% and 11% of the items, respectively. Items relating to memory for the names of people and the placement of common objects were represented on the greatest percentage of measures (56% each). Working group members reported that instrument selection decisions were often based on practical considerations beyond the study of SCD specifically, such as availability and brevity of measures. Results document the heterogeneity of approaches across studies to the emerging construct of SCD. We offer preliminary recommendations for instrument selection and future research directions including identifying items and measure formats associated with important clinical outcomes. PMID:26402085

  8. Psychophysiological measures of driver distraction and workload while intoxicated

    NARCIS (Netherlands)

    Rakauskas, M.E; Ward, N.J; Bernat, E.M; Cadwallader, M; Patrick, C.J; De Waard, D.

    2008-01-01

    The crash risk associated with cell phone use while driving is a contentious issue. Many states are introducing Advanced Traveler Information Systems (ATIS) that may be accessed with cell phones while driving (e.g., 511 Traveler Information Services). In these contexts, there is a need for relevant

  9. Workload Model Based Dynamic Adaptation of Social Internet of Vehicles.

    Science.gov (United States)

    Alam, Kazi Masudul; Saini, Mukesh; El Saddik, Abdulmotaleb

    2015-09-15

    Social Internet of Things (SIoT) has gained much interest among different research groups in recent times. As a key member of a smart city, the vehicular domain of SIoT (SIoV) is also undergoing steep development. In the SIoV, vehicles work as sensor-hub to capture surrounding information using the in-vehicle and Smartphone sensors and later publish them for the consumers. A cloud centric cyber-physical system better describes the SIoV model where physical sensing-actuation process affects the cloud based service sharing or computation in a feedback loop or vice versa. The cyber based social relationship abstraction enables distributed, easily navigable and scalable peer-to-peer communication among the SIoV subsystems. These cyber-physical interactions involve a huge amount of data and it is difficult to form a real instance of the system to test the feasibility of SIoV applications. In this paper, we propose an analytical model to measure the workloads of various subsystems involved in the SIoV process. We present the basic model which is further extended to incorporate complex scenarios. We provide extensive simulation results for different parameter settings of the SIoV system. The findings of the analyses are further used to design example adaptation strategies for the SIoV subsystems which would foster deployment of intelligent transport systems.

  10. Workload Model Based Dynamic Adaptation of Social Internet of Vehicles

    Directory of Open Access Journals (Sweden)

    Kazi Masudul Alam

    2015-09-01

    Full Text Available Social Internet of Things (SIoT has gained much interest among different research groups in recent times. As a key member of a smart city, the vehicular domain of SIoT (SIoV is also undergoing steep development. In the SIoV, vehicles work as sensor-hub to capture surrounding information using the in-vehicle and Smartphone sensors and later publish them for the consumers. A cloud centric cyber-physical system better describes the SIoV model where physical sensing-actuation process affects the cloud based service sharing or computation in a feedback loop or vice versa. The cyber based social relationship abstraction enables distributed, easily navigable and scalable peer-to-peer communication among the SIoV subsystems. These cyber-physical interactions involve a huge amount of data and it is difficult to form a real instance of the system to test the feasibility of SIoV applications. In this paper, we propose an analytical model to measure the workloads of various subsystems involved in the SIoV process. We present the basic model which is further extended to incorporate complex scenarios. We provide extensive simulation results for different parameter settings of the SIoV system. The findings of the analyses are further used to design example adaptation strategies for the SIoV subsystems which would foster deployment of intelligent transport systems.

  11. Significantly Reduced Blood Pressure Measurement Variability for Both Normotensive and Hypertensive Subjects: Effect of Polynomial Curve Fitting of Oscillometric Pulses.

    Science.gov (United States)

    Yang, Fangwei; Chen, Fei; Zhu, Mingping; Chen, Aiqing; Zheng, Dingchang

    2017-01-01

    This study aimed to compare within-subject blood pressure (BP) variabilities from different measurement techniques. Cuff pressures from three repeated BP measurements were obtained from 30 normotensive and 30 hypertensive subjects. Automatic BPs were determined from the pulses with normalised peak amplitude larger than a threshold (0.5 for SBP, 0.7 for DBP, and 1.0 for MAP). They were also determined from cuff pressures associated with the above thresholds on a fitted curve polynomial curve of the oscillometric pulse peaks. Finally, the standard deviation (SD) of three repeats and its coefficient of variability (CV) were compared between the two automatic techniques. For the normotensive group, polynomial curve fitting significantly reduced SD of repeats from 3.6 to 2.5 mmHg for SBP and from 3.7 to 2.1 mmHg for MAP and reduced CV from 3.0% to 2.2% for SBP and from 4.3% to 2.4% for MAP (all P oscillometric pulses had the ability to reduce automatic BP measurement variability.

  12. Automation of Methods for the Subjective Measuring of Factors in the Operation of Automated Information Systems by Means of VBA

    Directory of Open Access Journals (Sweden)

    Lyudmila V. Gorbatova

    2015-01-01

    Full Text Available This article describes the process of assessing the effectiveness of the operation of automated information systems in colleges using the method of pairwise comparison and discusses numerical representations used with the above method. The author lists methods for the subjective measuring of the effective operation of automated information systems. The article proposes a way to automate the methods that makes it possible to simplify performing calculations and reduce the amount of time it takes to determine the outcome of a specific task. The author provides an algorithm with the results of work carried out.

  13. Evaluation of changes in birefringence for samples subjected to various stress sources measured with polarization-sensitive OCT

    Science.gov (United States)

    Karnowski, Karol; Li, Qingyun; Villiger, Martin; Sampson, David D.

    2017-04-01

    Polarization-sensitive OCT (PS-OCT) has proven useful in determining the stress-induced birefringence of non-biological materials, but such utility in biological tissues subjected to stress has not been well studied yet. To study stress-induced birefringence of biological tissues, we use a swept-source PS-OCT system with passively depth-encoded, orthogonal polarization states in the illumination path and polarization-diversity detection and a Mueller formalism in post-processing. We present measurements of stress-induced changes in the birefringence of non-biological and biological samples that provide useful benchmarks in further assessing the utility of this approach.

  14. Measurement of effective alveolar carbon dioxide tension during spontaneous breathing in normal subjects and patients with chronic airways obstruction.

    OpenAIRE

    Jordanoglou, J.; Koulouris, N; Kyroussis, D.; Rapakoulias, P.; Vassalos, P.; Madianos, J.

    1995-01-01

    BACKGROUND--The measurement of effective alveolar carbon dioxide tension (PA-CO2eff) is still a matter of debate. It has, however, become common practice to use arterial instead of alveolar CO2 tension for computing alveolar oxygen tension (PAO2) and physiological dead space, not only in normal subjects but also in patients. The purpose of this study was to estimate alveolar CO2 tension during spontaneous breathing with a new bedside technique which is simple and non-invasive, and to compare ...

  15. Measuring the subjective: revisiting the psychometric properties of three rating scales that assess the acute effects of hallucinogens.

    Science.gov (United States)

    Bouso, José Carlos; Pedrero-Pérez, Eduardo José; Gandy, Sam; Alcázar-Córcoles, Miguel Ángel

    2016-09-01

    In the present study we explored the psychometric properties of three widely used questionnaires to assess the subjective effects of hallucinogens: the Hallucinogen Rating Scale (HRS), the Mystical Experience Questionnaire (MEQ), and the Addiction Research Center Inventory (ARCI). These three questionnaires were administered to a sample of 158 subjects (100 men) after taking ayahuasca, a hallucinogen whose main active component is N,N-dimethyltryptamine (DMT). A confirmatory factorial study was conducted to check the adjustment of previous data obtained via theoretical proposals. When this was not possible, we used an exploratory factor analysis without restrictions, based on tetrachoric and polychoric matrices and correlations. Our results sparsely match the theoretical proposals of the authors, perhaps because previous studies have not always employed psychometric methods appropriate to the data obtained. However, these data should be considered preliminary, pending larger samples to confirm or reject the proposed structures obtained. It is crucial that instruments of sufficiently precise measurement are utilized to make sense of the information obtained in the study of the subjective effects of psychedelic drugs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Simultaneous measures of kinematics and fMRI: relation between movement parameters and activation maps in healthy subjects

    Science.gov (United States)

    Gandolla, M.; Casellato, C.; Ferrante, S.; Ferrigno, G.; Baselli, G.; Molteni, F.; Martegani, A.; Frattini, T.; Pedrocchi, A.

    2010-03-01

    The objective of this study was to identify on healthy subjects the correlation between motor performances and brain activation maps, by the simultaneous use of functional magnetic resonance imaging (fMRI) and optoelectronic motion analysis system. The specific goal was to individuate how amplitude affects the related cerebral flow maps in active, passive and electrical stimulated (FES) movements. Ankle DorsiFlexion (ADF) was chosen as analyzed task because of its importance in the gait cycle. Firstly FES compatibility with fMRI images acquisition was assessed, both for the safety of the subject and of the device, and for mutual disturbances evaluation. We identified the experimental protocol so as to optimize the measured cerebral maps and the repeatability of the results. Intra-subject analysis of movement parameters along with brain activation mapping was performed. First level analysis to compare different execution modalities have been studied and preliminary qualitative results are reported. The long term application is the exploitation of the combined system in the evaluation of neurological patients where the definition of the motor tasks could be only partially accomplished depending on the patient residual functionality.

  17. The effects of cyclists present at rural intersections on speed behaviour and workload of car drivers : a driving simulator study.

    NARCIS (Netherlands)

    Duivenvoorden, C.W.A.E. Hogema, J.H. Hagenzieker, M.P. & Wegman, F.C.M.

    2014-01-01

    The objective was to gain insight in how the number of cyclists, the cyclist's approach direction and the cyclist's action affect speed and mental workload of drivers approaching rural intersections. Also, the effects of a speed-reducing measure on the interaction between cyclists and motorised

  18. Explaining the Links between Workload, Distress, and Work-Family Conflict among School Employees: Physical, Cognitive, and Emotional Fatigue

    Science.gov (United States)

    Ilies, Remus; Huth, Megan; Ryan, Ann Marie; Dimotakis, Nikolaos

    2015-01-01

    This study examined the intraindividual relationships among workload and affective distress; cognitive, physical, and emotional fatigue; and work-family conflict among school employees. Using a repeated-measure, within-person research design, the authors found that work demands and affective distress, as well as cognitive, emotional, and physical…

  19. Objectively measured sedentary behaviour and moderate and vigorous physical activity in different school subjects: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Kerli Mooses

    2017-01-01

    Full Text Available Abstract Background Evidence shows the positive influence of moderate and vigorous physical activity (MVPA and negative influence of sedentary time on health and academic achievement. Although schools can significantly contribute to overall physical activity, little is known about MVPA and sedentary behaviour in different school subjects in different grades. Methods Physical activity of 646 students from 18 schools (94 classes and from three school stages (grades 1–9, aged 7–16 was measured with accelerometry for 5 school days. Time and proportion of MVPA and sedentary time, also average sedentary bout length was calculated for native language (Estonian, mathematics, science, foreign language, music and crafts lessons. Results A total of 6363 lessons were measured, with lesson duration of 45 min. The average lesson time MVPA remained below 2.2 min in all school stages and in all subjects. Students in grades 4–6 had greatest decline in the proportion of lesson time MVPA in science (β = −1.9, 95%CI −3.1– -0.6 and music (−1.2, −2.1– -0.4 and in grades 7–9 in music (−1.7, −3.1– -0.3 lessons compared to grades 1–3. In grades 1–3 students spent on average 76% of lesson time (34.0 ± 7.0 min as sedentary, whereas in grades 7–9 the average proportion of sedentary time was 87% (38.9 ± 5.7 min. An average sedentary bout length increased from 13 min in grades 1–3 to 20 min in grades 7–9. An increase in sedentary bout length from grades 1–3 compared to grades 7–9 was present in most subjects, except crafts, with smallest increase in foreign language (6 min, 3.5–8.9 and greatest in music lessons (16.6 min, 11.9–21.3. Lessons with prolonged sedentary bouts formed a maximum 36% of all lessons in grades 1–3 and 73% in grades 7–9. Conclusion The long sedentary time, bout length and low MVPA in most subjects were unfavourable in respect of both health and academic achievement. Significantly

  20. Objectively measured sedentary behaviour and moderate and vigorous physical activity in different school subjects: a cross-sectional study.

    Science.gov (United States)

    Mooses, Kerli; Mägi, Katrin; Riso, Eva-Maria; Kalma, Maarja; Kaasik, Priit; Kull, Merike

    2017-01-23

    Evidence shows the positive influence of moderate and vigorous physical activity (MVPA) and negative influence of sedentary time on health and academic achievement. Although schools can significantly contribute to overall physical activity, little is known about MVPA and sedentary behaviour in different school subjects in different grades. Physical activity of 646 students from 18 schools (94 classes) and from three school stages (grades 1-9, aged 7-16) was measured with accelerometry for 5 school days. Time and proportion of MVPA and sedentary time, also average sedentary bout length was calculated for native language (Estonian), mathematics, science, foreign language, music and crafts lessons. A total of 6363 lessons were measured, with lesson duration of 45 min. The average lesson time MVPA remained below 2.2 min in all school stages and in all subjects. Students in grades 4-6 had greatest decline in the proportion of lesson time MVPA in science (β = -1.9, 95%CI -3.1- -0.6) and music (-1.2, -2.1- -0.4) and in grades 7-9 in music (-1.7, -3.1- -0.3) lessons compared to grades 1-3. In grades 1-3 students spent on average 76% of lesson time (34.0 ± 7.0 min) as sedentary, whereas in grades 7-9 the average proportion of sedentary time was 87% (38.9 ± 5.7 min). An average sedentary bout length increased from 13 min in grades 1-3 to 20 min in grades 7-9. An increase in sedentary bout length from grades 1-3 compared to grades 7-9 was present in most subjects, except crafts, with smallest increase in foreign language (6 min, 3.5-8.9) and greatest in music lessons (16.6 min, 11.9-21.3). Lessons with prolonged sedentary bouts formed a maximum 36% of all lessons in grades 1-3 and 73% in grades 7-9. The long sedentary time, bout length and low MVPA in most subjects were unfavourable in respect of both health and academic achievement. Significantly increasing sedentary time and sedentary bout length in older school stages highlights the need for

  1. Cardiorespiratory fitness, cardiovascular workload and risk factors among cleaners; a cluster randomized worksite intervention.

    Science.gov (United States)

    Korshøj, Mette; Krustrup, Peter; Jørgensen, Marie Birk; Prescott, Eva; Hansen, Åse Marie; Kristiansen, Jesper; Skotte, Jørgen Henrik; Mortensen, Ole Steen; Søgaard, Karen; Holtermann, Andreas

    2012-08-13

    Prevalence of cardiovascular risk factors is unevenly distributed among occupational groups. The working environment, as well as lifestyle and socioeconomic status contribute to the disparity and variation in prevalence of these risk factors. High physical work demands have been shown to increase the risk for cardiovascular disease and mortality, contrary to leisure time physical activity. High physical work demands in combination with a low cardiorespiratory fitness infer a high relative workload and an excessive risk for cardiovascular mortality. Therefore, the aim of this study is to examine whether a worksite aerobic exercise intervention will reduce the relative workload and cardiovascular risk factors by an increased cardiorespiratory fitness. A cluster-randomized controlled trial is performed to evaluate the effect of the worksite aerobic exercise intervention on cardiorespiratory fitness and cardiovascular risk factors among cleaners. Cleaners are eligible if they are employed ≥ 20 hours/week, at one of the enrolled companies. In the randomization, strata are formed according to the manager the participant reports to. The clusters will be balanced on the following criteria: Geographical work location, gender, age and seniority. Cleaners are randomized to either I) a reference group, receiving lectures concerning healthy living, or II) an intervention group, performing worksite aerobic exercise "60 min per week". Data collection will be conducted at baseline, four months and 12 months after baseline, at the worksite during working hours. The data collection will consist of a questionnaire-based interview, physiological testing of health and capacity-related measures, and objective diurnal measures of heart rate, physical activity and blood pressure. Primary outcome is cardiorespiratory fitness. Information is lacking about whether an improved cardiorespiratory fitness will affect the cardiovascular health, and additionally decrease the objectively

  2. Cardiorespiratory fitness, cardiovascular workload and risk factors among cleaners; a cluster randomized worksite intervention

    Science.gov (United States)

    2012-01-01

    Background Prevalence of cardiovascular risk factors is unevenly distributed among occupational groups. The working environment, as well as lifestyle and socioeconomic status contribute to the disparity and variation in prevalence of these risk factors. High physical work demands have been shown to increase the risk for cardiovascular disease and mortality, contrary to leisure time physical activity. High physical work demands in combination with a low cardiorespiratory fitness infer a high relative workload and an excessive risk for cardiovascular mortality. Therefore, the aim of this study is to examine whether a worksite aerobic exercise intervention will reduce the relative workload and cardiovascular risk factors by an increased cardiorespiratory fitness. Methods/design A cluster-randomized controlled trial is performed to evaluate the effect of the worksite aerobic exercise intervention on cardiorespiratory fitness and cardiovascular risk factors among cleaners. Cleaners are eligible if they are employed ≥ 20 hours/week, at one of the enrolled companies. In the randomization, strata are formed according to the manager the participant reports to. The clusters will be balanced on the following criteria: Geographical work location, gender, age and seniority. Cleaners are randomized to either I) a reference group, receiving lectures concerning healthy living, or II) an intervention group, performing worksite aerobic exercise “60 min per week”. Data collection will be conducted at baseline, four months and 12 months after baseline, at the worksite during working hours. The data collection will consist of a questionnaire-based interview, physiological testing of health and capacity-related measures, and objective diurnal measures of heart rate, physical activity and blood pressure. Primary outcome is cardiorespiratory fitness. Discussion Information is lacking about whether an improved cardiorespiratory fitness will affect the cardiovascular health

  3. Cardiorespiratory fitness, cardiovascular workload and risk factors among cleaners; a cluster randomized worksite intervention

    Directory of Open Access Journals (Sweden)

    Korshøj Mette

    2012-08-01

    Full Text Available Abstract Background Prevalence of cardiovascular risk factors is unevenly distributed among occupational groups. The working environment, as well as lifestyle and socioeconomic status contribute to the disparity and variation in prevalence of these risk factors. High physical work demands have been shown to increase the risk for cardiovascular disease and mortality, contrary to leisure time physical activity. High physical work demands in combination with a low cardiorespiratory fitness infer a high relative workload and an excessive risk for cardiovascular mortality. Therefore, the aim of this study is to examine whether a worksite aerobic exercise intervention will reduce the relative workload and cardiovascular risk factors by an increased cardiorespiratory fitness. Methods/design A cluster-randomized controlled trial is performed to evaluate the effect of the worksite aerobic exercise intervention on cardiorespiratory fitness and cardiovascular risk factors among cleaners. Cleaners are eligible if they are employed ≥ 20 hours/week, at one of the enrolled companies. In the randomization, strata are formed according to the manager the participant reports to. The clusters will be balanced on the following criteria: Geographical work location, gender, age and seniority. Cleaners are randomized to either I a reference group, receiving lectures concerning healthy living, or II an intervention group, performing worksite aerobic exercise “60 min per week”. Data collection will be conducted at baseline, four months and 12 months after baseline, at the worksite during working hours. The data collection will consist of a questionnaire-based interview, physiological testing of health and capacity-related measures, and objective diurnal measures of heart rate, physical activity and blood pressure. Primary outcome is cardiorespiratory fitness. Discussion Information is lacking about whether an improved cardiorespiratory fitness will affect

  4. Linear and non-linear heart rate metrics for the assessment of anaesthetists' workload during general anaesthesia.

    Science.gov (United States)

    Martin, J; Schneider, F; Kowalewskij, A; Jordan, D; Hapfelmeier, A; Kochs, E F; Wagner, K J; Schulz, C M

    2016-12-01

    Excessive workload may impact the anaesthetists' ability to adequately process information during clinical practice in the operation room and may result in inaccurate situational awareness and performance. This exploratory study investigated heart rate (HR), linear and non-linear heart rate variability (HRV) metrics and subjective ratings scales for the assessment of workload associated with the anaesthesia stages induction, maintenance and emergence. HR and HRV metrics were calculated based on five min segments from each of the three anaesthesia stages. The area under the receiver operating characteristics curve (AUC) of the investigated metrics was calculated to assess their ability to discriminate between the stages of anaesthesia. Additionally, a multiparametric approach based on logistic regression models was performed to further evaluate whether linear or non-linear heart rate metrics are suitable for the assessment of workload. Mean HR and several linear and non-linear HRV metrics including subjective workload ratings differed significantly between stages of anaesthesia. Permutation Entropy (PeEn, AUC=0.828) and mean HR (AUC=0.826) discriminated best between the anaesthesia stages induction and maintenance. In the multiparametric approach using logistic regression models, the model based on non-linear heart rate metrics provided a higher AUC compared with the models based on linear metrics. In this exploratory study based on short ECG segment analysis, PeEn and HR seem to be promising to separate workload levels between different stages of anaesthesia. The multiparametric analysis of the regression models favours non-linear heart rate metrics over linear metrics. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Lack of agreement between objective and subjective measures in the evaluation of masticatory function: A preliminary study.

    Science.gov (United States)

    Pedroni-Pereira, Aline; Marquezin, Maria Carolina Salomé; Araujo, Darlle Santos; Pereira, Luciano José; Bommarito, Silvana; Castelo, Paula Midori

    2018-02-01

    The evaluation of mastication is important to understand the masticatory behavior and diagnose feeding difficulties. The objective of this preliminary study was to verify if there is agreement between objective and subjective validated methods of chewing evaluation in a convenience sample which consisted of 32 adolescents (mean 15.5years), complete permanent dentition and free of tooth decay. The Quality of Masticatory Function Questionnaire with the Food-Mastication, Habits, Meat, Fruit and Vegetables domains was used in the subjective evaluation. The objective aspects consisted of maximum bite force (BF) and masticatory performance (MP) by mastication of cubes of test-material and sieving to determine the median particle size (X50) and distribution in the sieves ("b"), and by the colorimetric method using colorchangeable chewing gum. Data were submitted to exploratory analysis, normality test and correlation tests (Pearson/Spearman). The correlation between BF and X50 (r=-0.43; p=0.02) and between BF and MP chewing gum (r=0.53; p=0.002) was significant with large effect size. The MP evaluated by chewing gum correlated with X50 (r=-0.34; p=0.055), but not with "b" (r=-0.06; p=0.73), while "b" correlated only with X50 (r=0.52, p=0.002). No significant correlation was observed between the objective measures and the total score of the subjective evaluation; only a negative correlation was observed between "b" and Meat domain (r=-0.40; p=0.023). The objective methods showed moderate correlation with each other and no agreement between the objective and subjective methods was observed in this sample of healthy adolescents, emphasizing the importance of both aspects in the evaluation of masticatory function. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Using light scattering to measure the response of individual ultrasound contrast microbubbles subjected to pulsed ultrasound in vitro

    Science.gov (United States)

    Guan, Jingfeng; Matula, Thomas J.

    2004-11-01

    Light scattering was used to measure the radial pulsations of individual ultrasound contrast microbubbles subjected to pulsed ultrasound. Highly diluted Optison® or Sonazoid® microbubbles were injected into either a water bath or an aqueous solution containing small quantities of xanthan gum. Individual microbubbles were insonified by ultrasound pulses from either a commercial diagnostic ultrasound machine or a single element transducer. The instantaneous response curves of the microbubbles were measured. Linear and nonlinear microbubble oscillations were observed. Good agreement was obtained by fitting a bubble dynamics model to the data. The pulse-to-pulse evolution of individual microbubbles was investigated, the results of which suggest that the shell can be semipermeable, and possibly weaken with subsequent pulses. There is a high potential that light scattering can be used to optimize diagnostic ultrasound techniques, understand microbubble evolution, and obtain specific information about shell parameters. .

  7. Frequency-domain photon migration measurements of normal and malignant tissue optical properties in a human subject

    Energy Technology Data Exchange (ETDEWEB)

    Fishkin, J.B.; Coquoz, O.; Anderson, E.R.; Brenner, M.; Tromberg, B.J. [Beckman Laser Institute and Medical Clinic, University of California at Irvine, 1002 Health Sciences Road East, Irvine, California 92612 (United States)]|[EA Photonics, 2515 Fisk Lane, Redondo Beach, California 90278 (United States)

    1997-01-01

    A 1-GHz multifrequency, multiwavelength frequency-domain photon migration instrument is used to measure quantitatively the optical absorption ({mu}{sub a}) and effective optical scattering ({mu}{sub s}{sup {prime}}) of normal and malignant tissues in a human subject. Large ellipsoidal ({approximately}10-cm major axis, {approximately}6-cm minor axes) subcutaneous malignant lesions were compared with adjacent normal sites in the abdomen and back. Absorption coefficients recorded at 674, 811, 849, and 956 nm were used to calculate tissue hemoglobin concentration (oxyhemoglobin, deoxyhemoglobin, and total), water concentration, hemoglobin oxygen saturation, and blood volume fraction {ital in vivo}. Our results show that the normal and the malignant tissues measured in the patient have clearly resolvable optical and physiological property differences that may be broadly useful in identifying and characterizing tumors.{copyright} 1997 Optical Society of America

  8. Effect of Kinesiology Tape on Measurements of Balance in Subjects With Chronic Ankle Instability: A Randomized Controlled Trial.

    Science.gov (United States)

    de-la-Torre-Domingo, Carlos; Alguacil-Diego, Isabel M; Molina-Rueda, Francisco; López-Román, Antonio; Fernández-Carnero, Josué

    2015-12-01

    To examine the immediate and prolonged effects (7d) of Kinesiology Tape (KT) on balance in subjects with chronic ankle instability using computerized dynamic posturography (CDP). A 7-day follow-up, single-blind randomized controlled trial. University community. Subjects (N=36) were screened for possible eligibility criteria, and 30 successfully completed the study protocol. Of these, 15 were randomly assigned to the experimental group (KT: 5 men, 10 women), and 15 were assigned to the control group (placebo tape: 10 men, 5 women). The experimental group was taped for a lateral ankle sprain with KT. In the control group, a placebo tape was used. Balance was assessed under the following 3 conditions: without taping, immediately after application, and after 7 days of use. The CDP device used in this study was the Smart Equitest version 8.2. CDP analysis was conducted using the Sensory Organization Test (SOT). As primaries outcome measures, the composite SOT score and composite SOT strategy were chosen. The partial score for SOT condition 2 and its strategy were considered as the secondary outcomes measures. Repeated-measures analysis of variance (ANOVA) demonstrated that there was not a significant interaction between group and time in the composite SOT score (F=.239; P=.73), SOT condition 2 (F=.333; P=.705), and SOT strategy 2 (F=.899; P=.43). Additionally, repeated-measures ANOVA showed a significant effect for time (composite SOT score: F=40.69; P≤.01; SOT condition 2: F=4.61; P=.014; SOT strategy 2: F=.899; P=.413; composite SOT strategy: F=15.14; P≤.01). Specifically, post hoc analysis showed that both groups obtained improvements in composite SOT scores immediately after tape application and 7 days of use. According to our results, the SOT scores of both the KT and control groups improved during follow-up. No differences between them were observed during the follow-up in most balance measurements. The observed changes may be related to a subjective increase

  9. Prediction of periodontopathic bacteria in dental plaque of periodontal healthy subjects by measurement of volatile sulfur compounds in mouth air.

    Science.gov (United States)

    Kishi, Mitsuo; Ohara-Nemoto, Yuko; Takahashi, Masahiro; Kishi, Kayo; Kimura, Shigenobu; Aizawa, Fumie; Yonemitsu, Masami

    2013-03-01

    The aim of this study was to determine whether measurements of volatile sulfur compounds (VSCs) are useful to predict colonization of periodontopathic bacteria. For this purpose, we assessed the relationships among distributions of 4 species of periodontopathic bacteria in tongue coating and dental plaque, oral conditions including VSC concentration in mouth air, and smoking habit of periodontal healthy young subjects. The subjects were 108 young adults (mean age, 23.5±2.56 years) without clinical periodontal pockets. Information regarding smoking habit was obtained by interview. After VSC concentration in mouth, air was measured with a portable sulfide monitor (Halimeter(®)), non-stimulated saliva flow and dental caries status were assessed, and tongue coating and dental plaque samples were collected from the subjects. The tongue coating samples were weighed to determine the amount. The colonization of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Treponema denticola in both tongue coating and plaque samples was investigated using species-specific polymerase chain reaction assays. Significant relationships were observed between the colonization of periodontopathic bacteria in tongue coating and plaque samples, especially that of P. gingivalis. VSC concentration showed the most significant association with colonization of P. gingivalis in both tongue coating and dental plaque. Logistic regression analysis demonstrated that the adjusted partial correlation coefficient [Exp(B)] values for VSC concentration with the colonization of P. gingivalis, P. intermedia, and T. denticola in dental plaque were 135, 35.4 and 10.4, respectively. In addition, smoking habit was also shown to be a significant variable in regression models [Exp(B)=6.19, 8.92 and 2.53, respectively]. Therefore, receiver operating characteristic analysis was performed to predict the colonization of periodontal bacteria in dental plaque in the subjects divided by smoking

  10. The Fluctuation of Intraocular Pressure Measured by a Contact Lens Sensor in Normal-Tension Glaucoma Patients and Nonglaucoma Subjects.

    Science.gov (United States)

    Tojo, Naoki; Abe, Shinya; Ishida, Masaaki; Yagou, Takaaki; Hayashi, Atsushi

    2017-03-01

    We compared the fluctuation of intraocular pressure (IOP) in normal-tension glaucoma (NTG) patients and individuals with nonglaucoma eyes. We obtained continuous IOP values using a SENSIMED Triggerfish contact lens sensor. The eyes of 12 nonglaucoma subjects and 14 NTG patients were examined. In all 26 subjects, the IOP fluctuation was measured continuously for 24 hours with a contact lens sensor. We evaluated the range of IOP fluctuations over the 24-hour period separately for diurnal IOP and nocturnal IOP and identified each subject's maximum value. The range of IOP fluctuation were analyzed, cutoff level of IOP fluctuation was calculated using receiver operating characteristic curve analyses. The mean IOP in the NTG eyes was 11.5±2.4 mm Hg and that in the nonglaucoma eyes was 12.7±2.0 mm Hg, a nonsignificantly difference (P=0.175). The 24-hour range of IOP fluctuations in the NTG group was significantly larger than that of the nonglaucoma group (P=0.007). The percentage of NTG patients who had the peak time of IOP fluctuation during nocturnal sleep was 57.1%, whereas the corresponding rate for the nonglaucoma eyes was 91.7%. The cutoff level of IOP fluctuation for glaucoma was 442 mVeq (sensitivity=1.00; specificity=0.571). The range of IOP fluctuation was larger in the eyes with NTG than in the nonglaucoma eyes. This larger fluctuation might be one of the reasons underlying the aggravation of the visual field by NTG. Measurements of 24-hour continuous IOP might be one of the useful methods to distinguish NTG from nonglaucoma eyes.

  11. Love as a subjective corrlate of interpersonal relationships: attempts of defining of the concepts and methods of measurment

    Directory of Open Access Journals (Sweden)

    O. P. Zolotnyik

    2015-04-01

    Full Text Available This article is devoted to overview the scientific study of the phenomenon of love. Attempts of scientific knowledge presented by developed by sociologists and psychologists love theories, which defined, classified and measure this phenomenon. The paper proposed to review the most popular theory of love studying: the triangular theory of love for Robert J. Sternberg, classification styles love for John Alan Lee and transformational concept of A.Giddens. The importance of studying this subject is explained by the subjective definition by respondents of the role of love as correlates of interpersonal relationships. Love is considered as a factor that acts as a marriage motive and components, which ensures its durability. The complexity of the scientific understanding of love is the absence of clear empirical referents for fixation. The examined theory reaffirms their scientific hypotheses through the use of specific methods of measurement. It is offered for review: Scale of love and sympathy by Z.Rubin, Love Attitude Scale by Hendrick C. and Hendrick S. and scale of romantic relationships by Munro­Adams. These methodologies are widely used in modern scientific research, been undergo with modifications and adaptation depending on the cultural characteristics of the respondents. The phenomenon of love needs more scientific study with the aim of further categorization, require range of techniques selection and should be included  as a component in the sociological survey of interpersonal relationships.

  12. Influence of obesity and physical workload on disability benefits among construction workers followed up for 37 years.

    Science.gov (United States)

    Robroek, Suzan J W; Järvholm, Bengt; van der Beek, Allard J; Proper, Karin I; Wahlström, Jens; Burdorf, Alex

    2017-09-01

    The objectives of this study are to investigate the relation between obesity and labour force exit via diagnosis-specific disability benefits, and whether physical workload modifies this association. A longitudinal analysis was performed among 3 28 743 Swedish construction workers in the age of 15-65 years. Body weight and height were measured at a health examination and enriched with register information on disability benefits up to 37 years later. Diagnoses of disability benefits were categorised into cardiovascular diseases (CVDs), musculoskeletal diseases (MSDs), mental disorders and others. A job exposure matrix, based on self-reported lifting of heavy loads and working in bent forward or twisted position, was applied as a measure of physical workload. Cox proportional hazards regression analyses were performed, and the relative excess risk due to interaction (RERI) between obesity and physical workload was calculated. Obese construction workers were at increased risk of receiving disability benefits (HR 1.70, 95% CI 1.65 to 2.76), mainly through CVD (HR 2.30) and MSD (HR 1.71). Construction workers with a high physical workload were also more likely to receive a disability benefit (HR 2.28, 95% CI 2.21 to 2.34), particularly via MSD (HR 3.02). Obesity in combination with a higher physical workload increased the risk of disability benefits (RERI 0.28) more than the sum of the risks of obesity and higher physical workload, particularly for MSD (RERI 0.44). Obesity and a high physical workload are risk factors for disability benefit. Furthermore, these factors are synergistic risk factors for labour force exit via disability benefit through MSD. Comprehensive programmes that target health promotion to prevent obesity and ergonomic interventions to reduce physical workload are important to facilitate sustained employment. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial

  13. Musculoskeletal symptoms and associated risk factors among office workers with high workload computer use.

    Science.gov (United States)

    Cho, Chiung-Yu; Hwang, Yea-Shwu; Cherng, Rong-Ju

    2012-09-01

    Although the prevalence of reported discomfort by computer workers is high, the impact of high computer workload on musculoskeletal symptoms remains unclear. The purpose of this study was to investigate the prevalence of musculoskeletal symptoms for office workers with high computer workload. The association between risk factors and musculoskeletal symptoms was also assessed. Two questionnaires were posted on the Web sites of 3 companies and 1 university to recruit computer users in Tainan, Taiwan, during May to July 2009. The 12-item Chinese Health Questionnaire and Musculoskeletal Symptom Questionnaire were chosen as the evaluation tools for musculoskeletal symptoms and its associated risk factors. Chinese Health Questionnaire greater than 5 and computer usage greater than 7 h/d were used to as the cutoff line to divide groups. Descriptive statistics were computed for mean values and frequencies. χ(2) Analysis was used to determine significant differences between groups. A 0.05 level of significance of was used for statistical comparisons. A total of 254 subjects returned the questionnaire, of which 203 met the inclusion criteria. The 3 leading regions of musculoskeletal symptoms among the computer users were the shoulder (73%), neck (71%), and upper back (60%) areas. Similarly, the 3 leading regions of musculoskeletal symptoms among the computer users with high workload were shoulder (77.3%), neck (75.6%), and upper back (63.9%) regions. High psychologic distress was significantly associated with shoulder and upper back complaints (odds ratio [OR], 3.46; OR, 2.24), whereas a high workload was significantly associated with lower back complaints (OR, 1.89). Females were more likely to report shoulder complaints (OR, 2.25). This study found that high psychologic distress was significantly associated with shoulder and upper back pain, whereas high workload was associated with lower back pain. Women tended to have a greater risk of shoulder complaints than men

  14. Development of staffing evaluation principle for advanced main control room and the effect on situation awareness and mental workload

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chiuhsiang Joe, E-mail: cjoelin@mail.ntust.edu.tw [Department of Industrial Management, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Hsieh, Tsung-Ling, E-mail: bm1129@gmail.com [Institute of Nuclear Energy Research, 1000, Wenhua Road, Chiaan Village, Lungtan 32546, Taiwan (China); Lin, Shiau-Feng, E-mail: g9602411@cycu.edu.tw [Department of Industrial Engineering, Chung-Yuan Christian University, 200, Chung Pei Road, Chung-Li 32023, Taiwan (China)

    2013-12-15

    Highlights: • A staffing evaluation principle was developed for the advanced main control room. • The principle proposed to improve situation awareness and mental workload. • The principle has good validity that was examined by experimental design. - Abstract: Situation awareness and mental workload, both of which influence operator performance in the advanced main control room of a nuclear power plant, can be affected by staffing level. The key goal of staffing is to ensure the proper number of personnel to support plant operations and events. If the staffing level is not adaptive, the operators may have low situation awareness and an excessive mental workload, which lead to human error. Accordingly, this study developed a staffing evaluation principle based on CPM-GOMS modeling for operations in the advanced main control room. A within-subject experiment was designed to examine the validity of the staffing evaluation principle. The results indicated that the situation awareness, mental workload, and operating performance of the staffing level determined by the staffing evaluation principle was significantly better than that of the non-evaluated staffing level; thus, the validity of the staffing evaluation technique is acceptable. The implications of the findings of this study on managerial practice are discussed.

  15. NERSC-6 Workload Analysis and Benchmark Selection Process

    Energy Technology Data Exchange (ETDEWEB)

    Antypas, Katie; Shalf, John; Wasserman, Harvey

    2008-08-29

    This report describes efforts carried out during early 2008 to determine some of the science drivers for the"NERSC-6" next-generation high-performance computing system acquisition. Although the starting point was existing Greenbooks from DOE and the NERSC User Group, the main contribution of this work is an analysis of the current NERSC computational workload combined with requirements information elicited from key users and other scientists about expected needs in the 2009-2011 timeframe. The NERSC workload is described in terms of science areas, computer codes supporting research within those areas, and description of key algorithms that comprise the codes. This work was carried out in large part to help select a small set of benchmark programs that accurately capture the science and algorithmic characteristics of the workload. The report concludes with a description of the codes selected and some preliminary performance data for them on several important systems.

  16. Sex differences in objective measures of sleep in post-traumatic stress disorder and healthy control subjects.

    Science.gov (United States)

    Richards, Anne; Metzler, Thomas J; Ruoff, Leslie M; Inslicht, Sabra S; Rao, Madhu; Talbot, Lisa S; Neylan, Thomas C

    2013-12-01

    A growing literature shows prominent sex effects for risk for post-traumatic stress disorder and associated medical comorbid burden. Previous research indicates that post-traumatic stress disorder is associated with reduced slow wave sleep, which may have implications for overall health, and abnormalities in rapid eye movement sleep, which have been implicated in specific post-traumatic stress disorder symptoms, but most research has been conducted in male subjects. We therefore sought to compare objective measures of sleep in male and female post-traumatic stress disorder subjects with age- and sex-matched control subjects. We used a cross-sectional, 2 × 2 design (post-traumatic stress disorder/control × female/male) involving83 medically healthy, non-medicated adults aged 19-39 years in the inpatient sleep laboratory. Visual electroencephalographic analysis demonstrated that post-traumatic stress disorder was associated with lower slow wave sleep duration (F(3,82)  = 7.63, P = 0.007) and slow wave sleep percentage (F(3,82)  = 6.11, P = 0.016). There was also a group × sex interaction effect for rapid eye movement sleep duration (F(3,82)  = 4.08, P = 0.047) and rapid eye movement sleep percentage (F(3,82)  = 4.30, P = 0.041), explained by greater rapid eye movement sleep in post-traumatic stress disorder females compared to control females, a difference not seen in male subjects. Quantitative electroencephalography analysis demonstrated that post-traumatic stress disorder was associated with lower energy in the delta spectrum (F(3,82)  = 6.79, P = 0.011) in non-rapid eye movement sleep. Slow wave sleep and delta findings were more pronounced in males. Removal of post-traumatic stress disorder subjects with comorbid major depressive disorder, who had greater post-traumatic stress disorder severity, strengthened delta effects but reduced rapid eye movement effects to non-significance. These findings support previous evidence that post

  17. [Evaluation of nurse workload in patients undergoing therapeutic hypothermia].

    Science.gov (United States)

    Argibay-Lago, Ana; Fernández-Rodríguez, Diego; Ferrer-Sala, Nuria; Prieto-Robles, Cristina; Hernanz-del Río, Alexandre; Castro-Rebollo, Pedro

    2014-01-01

    Therapeutic hypothermia (TH) is recommended to minimize neurological damage in patients surviving sudden cardiac arrest (SCA). There is scarcity of data evaluating the nursing workload in these patients. The objective of the study is to assess the workload of nurses whilst treating patients undergoing TH after SCA. A 43-month prospective-retrospective comparative cohort study was designed. Patients admitted to intensive care unit, for recovered SCA and persistent coma, were included. A comparison was made using the baseline characteristics, medical management, in-hospital mortality, and nursing workload during the first 96hours using the Therapeutic Intervention Scoring System-28 (TISS-28); Nursing Activities Score (NAS); and Nine Equivalents of Nursing Manpower Use Score (NEMS) scales among patients who received TH and those who did not. A total 46 patients were included: 26 in the TH group and 20 in the Non-TH group. Regarding baseline characteristics and management, the TH group presented higher prevalence of smoking habit (69 vs. 25%, p=0.012), out-of-hospital SCA (96 vs. 55%, p<0.001), and the performance of coronary angiography (96 vs. 65%, p=0.014) compared with the non-TH group. No differences were observed in the nursing workload, assessed by TISS 28, NAS or NEMS scales, or in-hospital mortality. In this study performance of TH in SCA survivors is not associated with an increase in nursing workload. The installation of a TH program does not require the use of more nursing resources in terms of workload. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  18. New measures of upper esophageal sphincter distensibility and opening patterns during swallowing in healthy subjects using EndoFLIP®

    LENUS (Irish Health Repository)

    Regan, J

    2013-01-01

    Background  This paper aims to measure upper esophageal sphincter (UES) distensibility and extent and duration of UES opening during swallowing in healthy subjects using EndoFLIP(®) . Methods  Fourteen healthy subjects (20-50 years) were recruited. An EndoFLIP(®) probe was passed trans-orally and the probe balloon was positioned across the UES. Two 20-mL ramp distensions were completed and UES cross-sectional area (CSA) and intra-balloon pressure (IBP) were evaluated. At 12-mL balloon volume, subjects completed dry, 5- and 10-mL liquid swallows and extent (mm) and duration (s) of UES opening and minimum IBP (mmHg) were analyzed across swallows. Key Results  Thirteen subjects completed the study protocol. A significant change in UES CSA (P < .001) and IBP (P < .000) was observed during 20-mL distension. UES CSA increased up to 10-mL distension (P < .001), from which point IBP raised significantly (P = 0.004). There were significant changes in UES diameter (mm) (P < .000) and minimum IBP (mmHg) (P < .000) during swallowing events. Resting UES diameter (4.9 mm; IQR 0.02) and minimum IBP (18.8 mmHg; IQR 2.64) changed significantly during dry (9.6 mm; IQR 1.3: P < .001) (3.6 mmHg; IQR 4.1: P = 0.002); 5 mL (8.61 mm; IQR 2.7: P < .001) (4.8 mmHg; IQR 5.7: P < .001) and 10-mL swallows (8.3 mm; IQR 1.6: P < 0.001) (3 mmHg; 4.6: P < .001). Median duration of UES opening was 0.5 s across dry and liquid swallows (P = 0.91). Color contour plots of EndoFLIP(®) data capture novel information regarding pharyngo-esophageal events during swallowing. Conclusions & Inferences  Authors obtained three different types of quantitative data (CSA, IBP, and timing) regarding UES distensibility and UES opening patterns during swallowing in healthy adults using only one device (EndoFLIP(®) ). This new measure of swallowing offers fresh information regarding UES dynamics which may ultimately improve patient

  19. Significantly Reduced Blood Pressure Measurement Variability for Both Normotensive and Hypertensive Subjects: Effect of Polynomial Curve Fitting of Oscillometric Pulses

    Directory of Open Access Journals (Sweden)

    Fangwei Yang

    2017-01-01

    Full Text Available This study aimed to compare within-subject blood pressure (BP variabilities from different measurement techniques. Cuff pressures from three repeated BP measurements were obtained from 30 normotensive and 30 hypertensive subjects. Automatic BPs were determined from the pulses with normalised peak amplitude larger than a threshold (0.5 for SBP, 0.7 for DBP, and 1.0 for MAP. They were also determined from cuff pressures associated with the above thresholds on a fitted curve polynomial curve of the oscillometric pulse peaks. Finally, the standard deviation (SD of three repeats and its coefficient of variability (CV were compared between the two automatic techniques. For the normotensive group, polynomial curve fitting significantly reduced SD of repeats from 3.6 to 2.5 mmHg for SBP and from 3.7 to 2.1 mmHg for MAP and reduced CV from 3.0% to 2.2% for SBP and from 4.3% to 2.4% for MAP (all P<0.01. For the hypertensive group, SD of repeats decreased from 6.5 to 5.5 mmHg for SBP and from 6.7 to 4.2 mmHg for MAP, and CV decreased from 4.2% to 3.6% for SBP and from 5.8% to 3.8% for MAP (all P<0.05. In conclusion, polynomial curve fitting of oscillometric pulses had the ability to reduce automatic BP measurement variability.

  20. Comparison of dual-energy X-ray absorptiometry and magnetic resonance imaging-measured adipose tissue depots in HIV-infected and control subjects.

    Science.gov (United States)

    Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Punyanitya, Mark; Heymsfield, Steven B; Grunfeld, Carl

    2008-10-01

    Studies in persons without HIV infection have compared adipose tissue measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI), but no such study has been conducted in HIV-infected (HIV+) subjects, who have a high prevalence of regional fat loss. We compared DXA- with MRI-measured trunk, leg, arm, and total fat in HIV+ and control subjects. A cross-sectional analysis was conducted in 877 HIV+ subjects and 260 control subjects in FRAM (Study of Fat Redistribution and Metabolic Change in HIV Infection), stratified by sex and HIV status. Univariate associations of DXA with MRI were strongest for total and trunk fat (r > or = 0.92) and slightly weaker for leg (r > or = 0.87) and arm (r > or = 0.71) fat. The average estimated limb fat was substantially greater for DXA than for MRI for HIV+ and control men and women (all P < 0.0001). Less of a difference was observed in trunk fat measured by DXA and MRI, but the difference was still statistically significant (P < 0.0001). Bland-Altman plots showed increasing differences and variability. Greater average limb fat in control and HIV+ subjects (both P < 0.0001) was associated with greater differences between DXA and MRI measurements. Because the control subjects had more limb fat than did the HIV+ subjects, greater amounts of fat were measured by DXA than by MRI when control subjects were compared with HIV+ subjects. More HIV+ subjects had leg fat in the bottom decile of the control subjects by DXA than by MRI (P < 0.0001). Although DXA- and MRI-measured adipose tissue depots correlate strongly in HIV+ and control subjects, differences increase as average fat increases, particularly for limb fat. DXA may estimate a higher prevalence of peripheral lipoatrophy than does MRI in HIV+ subjects.

  1. Diabetic Foot Prevention: Repeatability of the Loran Platform Plantar Pressure and Load Distribution Measurements in Nondiabetic Subjects during Bipedal Standing—A Pilot Study

    Directory of Open Access Journals (Sweden)

    Martha Zequera

    2011-01-01

    Full Text Available This study was designed to assess the repeatability of the Loran Platform and evaluate the variability of plantar pressure and postural balance, during barefoot standing in nondiabetic subjects, for future diabetic foot clinical evaluation. Measurements were taken for eight nondiabetic subjects (4 females, 4 males, aged 47±7.2 years who had no musculoskeletal symptoms. Five variables were measured with the platform in the barefoot standing position. Ten measurements were taken using two different techniques for feet and posture positioning, during three sessions, once a week. For most measurements, no significant effect over time was found with Student's t-test (P<.000125. The ANOVA test of statistical significance confirmed that measurement differences between subjects showed higher variations than measurements taken from the same subject (P<.001. The measurements taken by the Loran Platform system were found to be repeatable.

  2. Prevalence of Hand-transmitted Vibration Exposure among Grass-cutting Workers using Objective and Subjective Measures

    Science.gov (United States)

    Azmir, N. A.; Yahya, M. N.

    2017-01-01

    Extended exposure to hand-transmitted vibration from vibrating machine is associated with an increased occurrence of symptoms of occupational disease related to hand disorder. The present case study is to determine the prevalence and correlation of significant subjective as well as objective variables that induce to hand arm vibration syndrome (HAVS) among hand-held grass-cutting workers in Malaysia. Thus, recommendations are made for grass-cutting workers and grass maintenance service management based on findings. A cross sectional study using adopted subjective Hand Arm Vibration Exposure Risk Assessment (HAVERA) questionnaire from Vibration Injury Network on hand disorder signs and symptoms was distributed to a sample of one hundred and sixty eight male workers from grass and turf maintenance industry that use vibrating machine as part of their work. For objective measure, hand-transmitted vibration measurement was collected on site during operation by the following ISO 5349-1, 2001. Two groups were identified in this research comprising of high exposure group and low-moderate exposure group. Workers also gave information about their personal identification, social history, workers’ health, occupational history and machine safety inspection. There was positive HAVS symptoms relationship between the low-moderate exposure group and high exposure group among hand-held grass-cutting workers. The prevalence ratio (PR) was considered high for experiencing white colour change at fingers and fingers go numb which are 3.63 (1.41 to 9.39) and 4.24 (2.18 to 8.27), respectively. The estimated daily vibration exposure, A(8) differs between 2.1 to 20.7 ms-2 for right hand while 2.7 to 29.1 ms-2 for left hand. The subjects claimed that the feel of numbness at left hand is much stronger compared to right hand. The results suggest that HAVS is diagnosed in Malaysia especially in agriculture sector. The A(8) indicates that the exposure value is more than exposure limit value

  3. Using the NASA Task Load Index to Assess Workload in Electronic Medical Records.

    Science.gov (United States)

    Hudson, Darren; Kushniruk, Andre W; Borycki, Elizabeth M

    2015-01-01

    Electronic medical records (EMRs) has been expected to decrease health professional workload. The NASA Task Load Index has become an important tool for assessing workload in many domains. However, its application in assessing the impact of an EMR on nurse's workload has remained to be explored. In this paper we report the results of a study of workload and we explore the utility of applying the NASA Task Load Index to assess impact of an EMR at the end of its lifecycle on nurses' workload. It was found that mental and temporal demands were the most responsible for the workload. Further work along these lines is recommended.

  4. A toolkit for clinical statisticians to fix problems based on biomarker measurements subject to instrumental limitations: from repeated measurement techniques to a hybrid pooled-unpooled design.

    Science.gov (United States)

    Vexler, Albert; Tao, Ge; Chen, Xiwei

    2015-01-01

    The aim of this chapter is to review and examine different methods in order to display correct and efficient statistical techniques based on complete/incomplete data subject to different sorts of measurement error (ME) problems. Instrument inaccuracies, biological variations, and/or errors in questionnaire-based self-report data can lead to significant MEs in various clinical experiments. Ignoring MEs can cause bias or inconsistency of statistical inferences. The biostatistical literature well addresses two categories of MEs: errors related to additive models and errors caused by the limit of detection (LOD). Several statistical approaches have been developed to analyze data affected by MEs, including the parametric/nonparametric likelihood methodologies, Bayesian methods, the single and multiple imputation techniques, and the repeated measurement design of experiment. We present a novel hybrid pooled-unpooled design as one of the strategies to provide correct statistical inferences when data is subject to MEs. This hybrid design and the classical techniques are compared to show the advantages and disadvantages of the considered methods.

  5. Wrist flexion and extension torques measured by highly sensitive dynamometer in healthy subjects from 5 to 80 years.

    Science.gov (United States)

    Decostre, Valérie; Canal, Aurélie; Ollivier, Gwenn; Ledoux, Isabelle; Moraux, Amélie; Doppler, Valérie; Payan, Christine Anne Mary; Hogrel, Jean-Yves

    2015-01-31

    Wrist movements become impaired with disease progression in various neuromuscular disorders. With the development of new therapies, thorough measurement of muscle strength is crucial to document natural disease progression and to assess treatment efficacy. We developed a new dynamometer enabling wrist flexion and extension torque measurement with high sensitivity. The aims of the present study were to collect norms for healthy children and adults, to compute predictive equations, to assess the reliability of the measurements and to test the feasibility of using the device in patients with a neuromuscular disease. The peak isometric torque of wrist flexion and extension was measured with the MyoWrist dynamometer in 345 healthy subjects aged between 5 and 80 years old and in 9 patients with limb girdle muscle dystrophy type 2 C (LGMD2C) aged between 16 and 38 years old. Predictive equations are proposed for the wrist flexion and extension strength in children and adults. Intra-rater and inter-rater reliability was good with ICCs higher than 0.9 for both wrist flexion and extension. However, retest values were significantly higher by 4% than test results. The dynamometer was applied with no difficulty to patients with LGMD2C and was sensitive enough to detect strength as weak as 0.82 N.m. From our models, we quantified the mean strength of wrist extension in LGMD2C patients to 39 ± 17% of their predicted values. The MyoWrist dynamometer provides reliable and sensitive measurement of both wrist flexion and extension torques. However, a training session is recommended before starting a study as a small but significant learning effect was observed. Strength deficit can be quantified from predictive equations that were computed from norms of healthy children and adults.

  6. Perceptual Factors in Workload: A Neuromagnetic Study.

    Science.gov (United States)

    1987-02-13

    progress, advancing methods of modeling field sources and enhacing techniques of data analysis, and conducting research designed to identify regions of the...the occipital and parietal regions. The subject lay prone on a bed and looked through an aperture down into a mirror which reflected the image on the...of the grating matched the background luminance of the screen. The gratings were generated using an Inisfree Picasso Image Generator driven by a PDP

  7. The value of the acoustic voice quality index as a measure of dysphonia severity in subjects speaking different languages.

    Science.gov (United States)

    Maryn, Youri; De Bodt, Marc; Barsties, Ben; Roy, Nelson

    2014-06-01

    The Acoustic Voice Quality Index (AVQI) is a relatively new clinical method to quantify dysphonia severity. Since it partially relies on continuous speech, its performance may vary with voice-related phonetic differences and thus across languages. The present investigation therefore assessed the AVQI's performance in English, Dutch, German, and French. Fifty subjects were recorded reading sentences in the four languages, as well as producing a sustained vowel. These recordings were later edited to calculate the AVQI. The samples were also perceptually rated on overall dysphonia severity by three experienced voice clinicians. The AVQI's cross-linguistic concurrent validity and diagnostic precision were assessed. The results support earlier data, and confirm good cross-linguistic validity and diagnostic accuracy. Although no statistical differences were observed between languages, the AVQI performed better in English and German and less well in French. These results validate the AVQI as a potentially robust and objective dysphonia severity measure across languages.

  8. The influence of N-acetylcysteine on the measurement of prothrombin time and activated partial thromboplastin time in healthy subjects

    DEFF Research Database (Denmark)

    Jepsen, S; Hansen, A B

    1994-01-01

    The purpose of the study was to evaluate whether the infusion of N-acetylcysteine decreased the measurement of prothrombin time and activated partial thromboplastin time (APTT) in healthy persons. N-acetylcysteine was administered intraveneously 10 mg kg-1 as a loading dose and then at a rate of 10...... mg kg-1 h-1 for 32 h in six male subjects. The intrinsic, extrinsic and common pathway of coagulation were monitored with activated partial thromboplastin time (APTT), and prothrombin time, respectively. In addition, the extrinsic coagulation pathway was monitored with the clotting activity of single...... factors II, VII, and X. No effect on the intrinsic coagulation pathway was observed. There was a significant and rapid decrease in prothrombin time. Coagulation factors II, VII and X, the three components of prothrombin time, decreased significantly to different degrees. We conclude that infusion of N...

  9. Relationship between knee kinetic outcome measures in vertical counter movement jumps and self-reported function in ACL reconstructed subjects

    DEFF Research Database (Denmark)

    Brekke, Anders Falk

    2014-01-01

    and Traumatology, Odense University Hospital, Institute of Clinical Research, University of Southern Denmark Introduction: Altered loading pattern of the medial aspect of the knee has been associated with the development of knee osteoarthritis (OA). Anterior cruciate ligament (ACL) injuries are associated......Relationship between knee kinetic outcome measures in counter movement jumps and self-reported function in ACL reconstructed subjects Brekke AF1,2, Nielsen DB2, Holsgaard-Larsen A2 1School of physiotherapy, University College Zealand, Denmark 2Orthopaedic Research Unit, Department of Orthopaedics...... with early-onset OA with associated pain, functional limitations, and decreased quality of life. However, specific knee loading pattern of the medial aspect has not been investigated during different jump-tasks in ACL-reconstructed patients. The purpose was to investigate potential kinetic differences...

  10. The effect of valgus braces on medial compartment load of the knee joint - in vivo load measurements in three subjects.

    Science.gov (United States)

    Kutzner, Ines; Küther, Steffen; Heinlein, Bernd; Dymke, Jörn; Bender, Alwina; Halder, Andreas M; Bergmann, Georg

    2011-04-29

    Knee osteoarthritis occurs predominately at the medial compartment. To unload the affected compartment, valgus braces are used which induce an additional valgus moment in order to shift the load more laterally. Until now the biomechanical effect of braces was mainly evaluated by measuring changes in external knee adduction moments. The aim of this study was to investigate if and to which extent the medial compartment load is reduced in vivo when wearing valgus braces. Six components of joint contact load were measured in vivo in three subjects, using instrumented, telemeterized knee implants. From the forces and moments the medio-lateral force distribution was calculated. Two braces, MOS Genu (Bauerfeind AG) and Genu Arthro (Otto Bock) were investigated in neutral, 4° and 8° valgus adjustment during walking, stair ascending and descending. During walking with the MOS brace in 4°/8° valgus adjustment, medial forces were reduced by 24%/30% on average at terminal stance. During walking with the GA in the 8° valgus position, medial forces were reduced by only 7%. During stair ascending/descending significant reductions of 26%/24% were only observed with the MOS (8°). The load reducing ability of the two investigated valgus braces was confirmed in three subjects. However, the load reduction depends on the brace stiffness and its valgus adjustment and varies strongly inter-individually. Valgus adjustments of 8° might, especially with the MOS brace, not be tolerated by patients for a long time. Medial load reductions of more than 25% can therefore probably not be expected in clinical practise. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Quantitative analysis of fluorescence lifetime measurements of the macula using the fluorescence lifetime imaging ophthalmoscope in healthy subjects.

    Science.gov (United States)

    Dysli, Chantal; Quellec, Gwénolé; Abegg, Mathias; Menke, Marcel N; Wolf-Schnurrbusch, Ute; Kowal, Jens; Blatz, Johannes; La Schiazza, Olivier; Leichtle, Alexander B; Wolf, Sebastian; Zinkernagel, Martin S

    2014-04-03

    Fundus autofluorescence (FAF) cannot only be characterized by the intensity or the emission spectrum, but also by its lifetime. As the lifetime of a fluorescent molecule is sensitive to its local microenvironment, this technique may provide more information than fundus autofluorescence imaging. We report here the characteristics and repeatability of FAF lifetime measurements of the human macula using a new fluorescence lifetime imaging ophthalmoscope (FLIO). A total of 31 healthy phakic subjects were included in this study with an age range from 22 to 61 years. For image acquisition, a fluorescence lifetime ophthalmoscope based on a Heidelberg Engineering Spectralis system was used. Fluorescence lifetime maps of the retina were recorded in a short- (498-560 nm) and a long- (560-720 nm) spectral channel. For quantification of fluorescence lifetimes a standard ETDRS grid was used. Mean fluorescence lifetimes were shortest in the fovea, with 208 picoseconds for the short-spectral channel and 239 picoseconds for the long-spectral channel, respectively. Fluorescence lifetimes increased from the central area to the outer ring of the ETDRS grid. The test-retest reliability of FLIO was very high for all ETDRS areas (Spearman's ρ = 0.80 for the short- and 0.97 for the long-spectral channel, P macula in healthy subjects. By using a custom-built software, we were able to quantify fluorescence lifetimes within the ETDRS grid. Establishing a clinically accessible standard against which to measure FAF lifetimes within the retina is a prerequisite for future studies in retinal disease.

  12. Reproducibility of heart rate variability parameters measured in healthy subjects at rest and after a postural change maneuver

    Directory of Open Access Journals (Sweden)

    E.M. Dantas

    2010-10-01

    Full Text Available Heart rate variability (HRV provides important information about cardiac autonomic modulation. Since it is a noninvasive and inexpensive method, HRV has been used to evaluate several parameters of cardiovascular health. However, the internal reproducibility of this method has been challenged in some studies. Our aim was to determine the intra-individual reproducibility of HRV parameters in short-term recordings obtained in supine and orthostatic positions. Electrocardiographic (ECG recordings were obtained from 30 healthy subjects (20-49 years, 14 men using a digital apparatus (sampling ratio = 250 Hz. ECG was recorded for 10 min in the supine position and for 10 min in the orthostatic position. The procedure was repeated 2-3 h later. Time and frequency domain analyses were performed. Frequency domain included low (LF, 0.04-0.15 Hz and high frequency (HF, 0.15-0.4 Hz bands. Power spectral analysis was performed by the autoregressive method and model order was set at 16. Intra-subject agreement was assessed by linear regression analysis, test of difference in variances and limits of agreement. Most HRV measures (pNN50, RMSSD, LF, HF, and LF/HF ratio were reproducible independent of body position. Better correlation indexes (r > 0.6 were obtained in the orthostatic position. Bland-Altman plots revealed that most values were inside the agreement limits, indicating concordance between measures. Only SDNN and NNv in the supine position were not reproducible. Our results showed reproducibility of HRV parameters when recorded in the same individual with a short time between two exams. The increased sympathetic activity occurring in the orthostatic position probably facilitates reproducibility of the HRV indexes.

  13. Impact of social prescribing on general practice workload and polypharmacy.

    Science.gov (United States)

    Loftus, A M; McCauley, F; McCarron, M O

    2017-07-01

    Social prescribing has emerged as a useful tool for helping patients overcome some of the social and behavioural determinants of poor health. There has been little research on the impact of social prescribing on use of primary healthcare resources. This study sought to determine whether social prescribing activities influenced patient-general practitioner (GP) contacts and polypharmacy. Quality-improvement design with social prescribing activity interventions from an urban general practice in Northern Ireland. Patients over 65 years of age with a chronic condition who attended their GP frequently or had multiple medications were offered a social prescribing activity. Participants' contacts with GP and the new repeat prescriptions before and during the social prescribing activity were measured. The total number of repeat prescriptions per patient was compared at the time of referral and 6-12 months later. Indications for referral, primary diagnoses and reasons for declining participation in a social prescribing activity after referral were prospectively recorded. Sixty-eight patients agreed to participate but only 28 (41%) engaged in a prescribed social activity. There was no statistically significant difference in GP contacts (visits to GP, home visits or telephone calls) or number of new repeat prescriptions between referral and completion of 12 weeks of social prescribing activity. Similarly there was no statistically significant difference in the total number of repeat prescriptions between referral and 6-12 months after social prescribing activity in either intention to treat or per protocol analyses. Social prescribing participants had similar demographic factors. Mental health issues (anxiety and/or depression) were more common among participants than those who were referred but declined participation in a social prescribing activity (P = 0.022). While social prescribing may help patients' self-esteem and well-being, it may not decrease GP workload. Further

  14. Effects of arotinolol on exercise capacity and humoral factors during exercise in normal subjects.

    Science.gov (United States)

    Mori, T; Handa, K; Terao, Y; Tanaka, H; Kiyonaga, A; Shindo, M; Matsunaga, A; Sasaki, J; Arakawa, K

    1992-08-01

    A placebo-controlled, double-blind crossover study was undertaken in 10 normal subjects to examine the effects of arotinolol (10 mg bid), a nonselective beta blocker with alpha-blocking activity, on exercise capacity and hormone levels during exercise after a 2-week treatment period. Maximal oxygen uptake (VO2 max) and blood lactic acid concentration (LA) were measured during progressive exercise testing. An exercise intensity equivalent to 4 mmol/l of LA was used for the constant workload exercise test. Humoral factors were measured after 20 minutes of constant workload exercise. The administration of arotinolol significantly decreased systolic blood pressure and heart rate at rest and during exercise, but diastolic blood pressure did not change. No significant difference was found between arotinolol and placebo with regard to VO2 max and maximal workload. Plasma renin activity (PRA), aldosterone (PAC), and norepinephrine (NE) levels at rest and during exercise did not differ between the two treatments. In contrast, plasma epinephrine (EN) levels at rest and during exercise were significantly greater with arotinolol. Atrial natriuretic peptide (ANP) at rest did not differ between the two treatments. However, exercise caused a significant increase in ANP after arotinolol treatment. These findings suggest that arotinolol decreases blood pressure and heart rate without affecting exercise capacity.

  15. No-sedation during mechanical ventilation: impact on patient's consciousness, nursing workload and costs.

    Science.gov (United States)

    Laerkner, Eva; Stroem, Thomas; Toft, Palle

    2016-01-01

    Evidence is growing that less or no-sedation is possible and beneficial for patients during mechanical ventilation. To investigate if there was a difference in patient consciousness and nursing workload comparing a group of patients receiving no-sedation with a group of sedated patients with daily wake up, and also to estimate economic consequences of a no-sedation strategy. Data were collected during a prospective trial of 140 mechanically ventilated patients randomized to either no-sedation or to sedation with daily wake up. From day 1 to 7 in the intensive care unit (ICU), patients were Richmond Agitation and Sedation Scale (RASS) scored, nursing workload was measured with the Nursing Care Recording System (NCR11) and nurse's self-assessment of workload was reported on a Numeric Rating Scale from 1 (low) to 10 (high). P