2.6. Analysis of clinical data

IBM SPSS Statistics 26.0 was utilized to perform statistical analysis on various factors including age, years of education, BMI, 17-HAMD scores, disease duration, and the number of NSSI behaviors for both the depressed adolescent group and the HC group. The normality of the data was tested using the Shapiro–Wilk test. For normally distributed and homogeneous data, descriptive statistics (mean ± standard deviation,⁻x ± s) were used, and group comparisons were conducted with independent samples t-tests. For data that did not meet the assumptions of normality, medians with corresponding quartiles M (P25–P75) were used, and group comparisons were performed using non-parametric tests (Mann–Whitney U-test). Gender distribution between the depressed adolescent group and the HC group was presented as frequencies, and a Pearson chi-square test was conducted for group comparisons. p < 0.05 was considered statistically significant.