Comprehensive Technology-Assisted Training and Supervision Program to Enhance Depression Management in Primary Care

A cluster randomized controlled clinical trial will be conducted in four Primary Health Care (PHC) clinics in Santiago, Chile.

The sample selection of the PHC clinics will be performed in two steps. Firstly, two urban municipalities of Santiago Metropolitan Region, Chile, will be randomly selected if they work with the Faculty of Medicine of the U.Chile and have at least two PHC.Municipalities with a high Human Development Index, high percentage of immigrants and older population, and Psychiatry residents working in PHC , will be excluded.Secondly in each selected municipalities,two PHC will be randomly selected for the active and control arm.

To detect a difference of 20%, in a one-sided model, with an alpha of 5% and power of 80%, 152 depressed persons, 76 to each group, will be required for the study. A design effect of 2.42 was estimated. After applying the design effect the sample needed increased to 368 depressed persons. Considering a retention rate of approximately 85%, 434 depressed cases will be needed required for the study, hence 109 cases in each of the 4 primary health care clinics.

Analysis and presentation of the results will be in accordance with CONSORT guidelines for randomized clinical trials, with the primary comparative analysis being conducted on an intention to treat basis and due emphasis placed on confidence intervals for the between-arm comparisons.

Initially descriptive analysis to assess the balance between two groups will be conducted. The primary analysis will employ multilevel multivariable lineal regression to investigate differences in the PHQ-9 scores between groups at 3 and 6 months after randomization, adjusting for baseline outcome variable scores. Sensitivity analysis making different assumptions will be conducted to investigate the potential effects of missing data. Similar analysis will be done for the secondary outcomes measures.