Data analysis
Data were analyzed using SPSS software version 22. Descriptive tests were used to describe the data. Qualitative variables between the intervention and control groups were compared using the Chi-square test and Fisher’s exact test. Mean differences of water pipe dependence scores (P = 0.002), mean water pipe dependence scores before (p = 0.02) and after (p < 0.001) the intervention, and happiness scores before intervention (P = 0.009) did not have a normal distribution. The before-after, between-group and within-group variables were compared by the independent t-test or the Mann-Whitney test and the Wilcoxon test, respectively. The Cohen’s d effect size was calculated to evaluate the clinical significance of the findings. The effect sizes of 0.8, 0.5, and 0.2 were considered large, medium, and small, respectively [