Journal of School of Public Health and

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Background and Aim: In 1991, the world health organization initiated a project to simultaneously develop an instrument for measuring quality of life in 15 countries. The study yielded two questionnaires, namely WHOQOL-100 and WHOQOL-BREF. These were intended as generic QOL measurement tools to be used in a broad range of diseases, for different degrees of disease severity, and in various cultural subgroups. The objective of the current study was to evaluate the Iranian version of the WHOQOL-BREF. This 26-item instrument comprises four domains: Physical Health, Psychological, Social Relationship, Environment and the overall QOL/health.
Material and Methods: We administered the questionnaire to 1167 adults in Tehran. The stratified sample consisted of 476 diseased subjects and 700 healthy ones. We tested the instrument's reliability (internal consistency, test-retest), discriminant validity and factorial structure.
Results: The participants had an age mean of 36.3 years (SD = 13.2) and had an average 11.5 years of education. Using Cronbach's α and intraclass correlation, all domains met the minimum reliability standards, with the exception of social relationship domain (α = 0.55). The latter could be attributed the small number of questions in this domain and the sensitive nature of the questions themselves. Since 83% of the questions show maximum correlation with their original domain, the factorial structure of the questionnaire was regarded as acceptable. The questionnaire has the ability to discriminate different groups after adjustment for confounding factors in regression analysis.
Conclusion: This study demonstrated good to excellent reliability and acceptable validity in various groups of subjects in Iran. The instrument may be used in future studies, albeit with minor modifications in the domain of social relations, as determined by expert opinion.

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  Background and Aim : Diagnostic tools for chronic fatigue syndrome, chronic fatigue syndrome questionnaire, created for research and clinical investigations in order to use it as a management tool for monitoring patients with this syndrome. The questionnaire is very comprehensive using a self-reporting system and all internal and external definitions according to the America's Center for Disease Control has been covered. It also assesses current and past activity levels and symptoms of fatigue and malaise after routine daily activities to ensure that these items are evaluated as well. The purpose of this study is to evaluate the reliability and validity of diagnostic questionnaire for Chronic Fatigue Syndrome (CFS).

  Materials and Methods : In the discussion of content validity and reliability of survey studies, chronic fatigue syndrome questionnaire, prepared by the Department of Psychology, DePaul University, and was elected a full copy of the correspondence received from the questionnaire ratings. The questionnaire that was translated content validity was assessed by the 20 members of the faculty. However, re-translated from Persian into English for reference, was prepared with modifications, the validity of its validity was confirmed by the authors. Then, 30 nurses were selected to determine the reliability of the questionnaire chronic fatigue syndrome who was working in a Hospital. Inventory management under center and full justification of the researcher and the participants in the study by researchers at the distribution has been completed. The survey was carried out again after 15 days.

  Results: The instrument showed good reliability and validity. In discussing the content validity of the Persian translation tool by 20 people associated professor of internal review, and its content validity was determined with respect to two of CVI and the results of CVR , and (CVR=0.7 and CVI=0.85) represents CREDIT the content is good . According to the results, the reliability of the questionnaire CFS, Cronbach's alpha to assess the results of the questionnaire showed very good reliability. Two step test reliability coefficients (ICC = Mixed & and Confidence Interval = 95%) also showed a significant relationship among questions as well. However, the internal correlation coefficient obtained for the 8 criteria CFS, showed high internal cohesion.

  Conclusion: This study suggests the CFS questionnaire as a reliable instrument for all levels in research and clinical applications. Using this tool can help with background checks and even in advanced levels to be effective, it has enough power and accuracy in the diagnosis of CFS sufferers.

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  Background and Aim: Work ability reflects the interactions among personal characteristics, working conditions, employees' functional capabilities, and also employees' health status. Hence, the aim of the present study was to provide the Farsi version of Work Ability Index and to validate it among Iranian workers.

  Materials and Methods: In the first stage, Backward Translation method was used for linguistic validation of the questionnaire. Cross sectional survey of a sample of 645 workers from some Iranian companies were conducted. The study estimated the reliability of the questionnaire by means of test-retest, as well as the construct validity using factor analysis. In order to determine discriminant capacity, the mean scores of different dimensions of work ability index were compared between workers with and without sick leave.

  Results: Accordingly, the questionnaire showed a good internal consistency. ICC coefficients for the questionnaire were acceptable. Moreover, factor analyses related to the questionnaire items indicated that only one question is sufficient for each item of "work ability in relation to the demands of the job" and "mental resources". Also, questions related to the item of "number of current diseases diagnosed by physician" can be integrated in six questions. A good level of discriminant validity was observed for all dimensions except for the item of "work ability regarding work demands".

  Conclusion: According to the acceptable validity and reliability of Work Ability Index, obtained in the present study, using this questionnaire for evaluating workers' work ability in all Iranian work environments, especially in industrial settings, is recommended.