BackgroundThe worldwide trend of hookah use among adolescents is increasing, and literature shows a relationship between obscenity and adolescents’ tendency toward hookah smoking. As there is a lack of appropriate instruments to measure the obscenity of hookah smoking, in the present study, we aimed to develop an instrument to measure hookah smoking obscenity among adolescents.MethodsIn this methodological study, a sequential exploratory design was used to conduct the study from February 2017 to July 2018 on adolescents in Tabriz, Iran. In the qualitative phase, we conducted semi-structured individual interviews (with 18 students) and a focus group discussion (FGD) (with 13 students) to explain the concept of obscenity and develop the items of hookah smoking obscenity scale (HSOS). We then examined the psychometric properties of the HSOS based on face, content, construct and predictive validities as well as internal consistency and repeatability.FindingsThe HSOS was developed with 21 items based on the results of qualitative data analysis. Applying confirmatory factor analysis (CFA), the χ2/degree of freedom (df) ratio was found to be 3.792 for the four-factor structure of the questionnaire and the fit indices of this structural model were satisfactory. The values of Cronbach’s alpha and the intraclass correlation coefficient (ICC) for the constructs in the HSOS ranged 0.81-0.93 and 0.79-0.92, respectively.ConclusionWe found the HSOS with a good level of fit indices, validity, and reliability. The HSOS may be applied by school healthcare providers and health practitioners to find valid and reliable data on the obscenity of hookah smoking when developing hookah smoking prevention/cessation interventions among adolescents.