Water-pipe smoking addiction in Iran; Evaluation of reliability and validity of lebanon water-pipe dependence scale among Iranian water-pipe tobacco smokers

Background: Water-pipe smoking is increasing around the world. However, there is no comprehensive information on nicotine addiction in water-pipe smokers. This study was carried out to translate and validate the Lebanon Water-pipe Dependence Scale- into Persian language; besides, tobacco dependence was evaluated in Iranian water-pipe smokers. Methods: A forward-backward translation procedure was done to provide the Iranian version of the questionnaire. Our subjects were current water-pipe smokers who were known in prevalence study that conducted in Tehran. Psychometric properties of the instrument including validity (content, face and construct validity) and reliability (internal consistency and test-retest analysis), were evaluated. Results: A total of 465 participants took part in this study, of whom 298 (64%) were male. The mean age was 30 (standard deviation 10.2). Fifty three percent of subjects got score more than 10 on LWDS questionnaire that indicating dependence. The internal consistency of the LWDS (Persian Version) was 0.85. The physiologic dependence, psychological craving, and negative reinforcement domains had acceptable reliability (Cronbach's alpha was 0.94, 0.81, 0.77 respectively), but reliability was low (alpha = 0.45) in the positive reinforcement domain. External consistency of the LWDS was assessed by test retest. Intra class correlation (ICC) was calculated for all items (n = 20) and ICC for all of them was >0.7 and the mean ICC was 0.9. Content validity was acceptable; all of obtained content validity indexes (CVIs) were above 80%. The result of goodness of fit shows an adequate model (Comparative Fit Index (CFI = 0.94), Root Mean Square Error of approximation (RMSE) = 0.08). Conclusions: The study revealed strong documents for the reliability and validity of the LWDS for use in Iran. However, further study may be required to improve the reliability results in the positive reinforcement domain.