Fig. 3
Forest plot of the relationship between sleep disorders and suicidal behaviour in depressed patients, N = 198,893. The data are expressed as odds ratios and the corresponding 95% confidence intervals. Pooled effect evaluation, represented by a diamond, was obtained with a random effects model. The heterogeneity between studies was explored by Cochran’s Q test and the I2 statistic, where I2 > 50% was considered evidence of substantial heterogeneity