3.3. Beck's Depression Inventory

This questionnaire was published by Khledian et al. is one of the most common tools for measuring depression. It consists of 21 four-choice questions and has an acceptable validity. The average homogeneity coefficient of was reported to be 0.86. Internal consistency coefficient was 0.78, and retest reliability was 0.73 (22). In a study, total reliability of depression using Cronbach’s alpha coefficient was reported to be 0.87 (23).

After data collection, mean, standard deviation, and frequency were used to classify and summarize the data. For data analysis, Kolmogorov-Smirnov test was used to investigate normality of data distribution. Pearson correlation coefficient was used to determine two-way correlations between variables, and regression test was used. All analyses were performed at 95% confidence level using the SPSS software version 22.