2.5 Statistical analysis
The reliability and validity of the Turkish HPMDQ were measured using internal consistency and test–retest statistical tools. To calculate the overlap in the HPMDQ response scores of the same people at different time points (i.e., initially and one month later), the intraclass correlation coefficient (ICC) was calculated for the aggregate scoring and the weighted Cohen’s kappa was calculated for the scoring of each item. Concurrent validity was evaluated using correlation with outer criteria (IPSS). Correlation coefficients of 0.1 weak, 0.3 medium and 0.5 strong were used, as proposed by Cohen.
Statistical analysis was completed using the IBM Statistical Package for the Social Sciences, version 22.0 (IBM SPSS Statistics]). The level of significance was set at p < 0.05, internal consistency reliability was evaluated using Cronbach’s alpha, and test–retest reliability was assessed using the Wilcoxon signed-rank test. Spearman correlation analysis was used for simultaneous external validity. Consistency and reliability are assumed sufficient for values >0.70.