Development and Psychometric Evaluation of the ergonomic office work assessment questionaire

Abstract

Introduction and aim: Most epidemiological studies conducted among office workers shows that ergonomics factors such as physical design in the workplace Office workplace, work organization and psychosocial aspects are associated with physical discomfort among employees. Important risk factors associated with office work, including occupational factors (design of work stations, Toolbar, repetitive work, prolonged sitting, poor posture, turning and bending the body and speed of work), environmental factors (light, noise, cold, heat and ventilation) and psychosocial factors (need work, stress, freedom of decision-making and social interaction). The study aims was to design a valid and reliable tool for Ergonomic office work assessment Method: This was a “tool development” and methodological study conducted in Tabriz University of Medical Sciences. Initially by literature review and also by holding a focus group discussion with experts (ergonomist, occupational health and Psychologist recruited by the main indices for evaluation of ergonomic office work assessment were determined. Then, after classification of the indices, the first draft of the evaluation tool was developed. The face validity and content validity of the tool were determined with the lawshe method and its reliability was determined with the test-retest method and alpha cronbach’s alpha coefficient in SPSS-21. The reliability of questionnaire was determined based on the results of 472 questionnaires fulfilled by University staff. Results: Content analysis of the focus group discussion resulted in 39 indexes.The final tool was adjusted in three separate questionnaires. The correlation coefficient (test - retest) of the questionnaire for "work station”, including 15 indexes, was 0.96, its cronbach’s alpha coefficient was 0.95. The correlation coefficient (test-retest) of the questionnaire for " environmental factors”, including 8 indexes, was 0.86, its cronbach’s alpha was 0.92. The correlation coefficient of the questionnaire for " psychosocial factors”, including 16 indexes was 0.88, its cronbach’s alpha coefficient was 0.93 . In addition, high values of item-scale correlations confirmed the convergence validity. Other goodness of fit indices such as GFI (0.91), AGFI (0.88), CFI (0.90) and NNFI (0.95) were also closer in terms of amount to relevant standard indices. Conclusion: The tool designed for for Ergonomic Office Work Asessment has appropriate and acceptable validity and reliability.