Psychometrics of the Instrument Measuring Beliefs Related to Drug Abuse among Iranian College Students Farzad Jalilian 1 Mehdi Mirzaei Alavijeh 1 Mohammad Ahmadpanah 2 Behzad Karami Matin 1 Mari Ataee 1 Ahmad Ali Eslami 3 Touraj Ahmadi Jouybari 1 Mohammad Mahboubi 4 Abstract Background: Researchers in the field of drug abuse need standard instruments in order to investigate the underlying factors behind the inclination to use drugs in different groups of society so that they could be able to design preventive interventions based on those instruments. The aim of this study is psychometrics of the questionnaire of the beliefs related to drug abuse among Iranian male medical college students. Methods: This cross-sectional study was done on 425 male students who were randomly selected to participate voluntarily in the study conducted in two medical universities in Iran. The studied constructs included attitude, outcome expectation, outcome expectancies, self-control and subjective norms. Data were analyzed by SPSS software (ver. 21.0) and Amos software (ver. 21.0). Results: All of the loads of the exploratory factorial analysis were larger than 0.4. The calculated Kaiser–Meyer–Olkin (KMO) value was 0.906. Overall, five factors under investigation accounted for 61.15 per cent of the variance in the hypothesized model. Cronbach’s alpha for the measured constructs Journal of Health Management 19(3) 1–10 © 2017 Indian Institute of Health Management Research SAGE Publications sagepub.in/home.nav DOI: 10.1177/0972063416651595 http://jhm.sagepub.com Article Corresponding author: Ahmad Ali Eslami, Phd in Health Education, Department of Health Education and Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. E-mail: health_fj@yahoo.com 1 Research Center for Environmental Determinants of Health, Kermanshah University of Medical Sciences, Kermanshah, Iran. 2 Behavioral Disorders and Substances Abuse Research Center, Hamadan University of Medical Sciences, Hamadan, Islamic Republic of Iran. 3 Department of Health Education and Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Islamic Republic of Iran. 4 Abadan School of Medical Sciences, Abadan, Iran.