1Department of Environmental Health Engineering, School of Health, Kurdistan University of Medical Sciences, Sanandaj, Iran
2Department of Public Health, School of Health, Kurdistan University of Medical Sciences, Sanandaj, Iran
3Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran
Creating awareness and recognizing behavioral factors associated with recycling is essential for waste management. To identify factors influencing recycling behavior, a theory of planned behavior (TPB)-based questionnaire was designed. The aim of this study was to assess the validity and reliability of the questionnaire. This psychometric study was conducted through a multistage random sampling on 283 homemakers of Mahabad Town, Iran, in 2014. The method recommended by Ajzen and Francis was used for designing the questionnaire. Its validity was evaluated using quantitative and qualitative face validity, ration and content validity index, and qualitative judgment of an expert panel of 8 members and its structural validity using exploratory factor analysis. In addition, its reliability was assessed using internal consistency (Cronbach's alpha coefficient) and retest (intraclass correlation) methods. Of the 53 initial questions, after calculating the content validity ratio (CVR) with values higher than 0.80 and content validity index (CVI) with values higher than 0.79, we modified 3 questions and deleted 8 questions; therefore, 45 questions were approved. Using exploratory factor analysis with a varimax rotation, 9 factors with a value of higher than 1 were selected, which were able to predict 91.81% of the total variation. The reliability of the tool was confirmed through calculating Cronbach's alpha (0.87). Results of retest indicated the consistency of the questionnaire. This research found that the Persian version of the Theory of Planned Behavior Questionnaire (TPB questionnaire) has suitable validity and reliability and can be used in research and administrative activities on increasing the participation of homemakers in municipal solid waste source separation.