Sample size
depression
A sample size of at least 25 patients per group was calculated, giving a power of 80% to detect the target difference in depression (as a critical variable obtained from a previous study) [Patients were assigned into two groups using permuted block randomization with two size blocks (case and control) and a random number table. To hide the treatment, the statistical advisor who was not involved in the study encoded the identical boxes of the capsules and generated the random sequence. Randomization and allocation were hidden from both the researchers and the patients until the final analyses were completed. The randomized allocation sequence, enrollment of patients, and allocation to interventions were operated by trained staff.