Abstract

IMPORTANCE Depression and anxiety are common mental disorders globally but are rarely recognized or treated in low-income settings. Task-shifting of mental health care to lay health workers (LHWs) might decrease the treatment gap. OBJECTIVE To evaluate the effectiveness of a culturally adapted psychological intervention for common mental disorders delivered by LHWs in primary care. DESIGN, SETTING, AND PARTICIPANTS Cluster randomized clinical trial with 6 months' follow-up conducted from September 1, 2014, to May 25, 2015, in Harare, Zimbabwe. Twenty-four clinics were randomized 1: 1 to the intervention or enhanced usual care (control). Participants were clinic attenders 18 years or older who screened positive for common mental disorders on the locally validated Shona Symptom Questionnaire (SSQ-14). INTERVENTIONS The Friendship Bench intervention comprised 6 sessions of individual problem-solving therapy delivered by trained, supervised LHWs plus an optional 6-session peer support program. The control group received standard care plus information, education, and support on common mental disorders. MAIN OUTCOMES AND MEASURES Primary outcome was common mental disorder measured at 6 months as a continuous variable via the SSQ-14 score, with a range of 0 (best) to 14 and a cutpoint of 9. The secondary outcome was depression symptoms measured as a binary variable via the 9-item Patient Health Questionnaire, with a range of 0 (best) to 27 and a cutpoint of 11. Outcomes were analyzed by modified intention-to-treat. RESULTS Among 573 randomized patients (286 in the intervention group and 287 in the control group), 495 (86.4%) were women, median age was 33 years (interquartile range, 27-41 years), 238 (41.7%) were human immunodeficiency virus positive, and 521 (90.9%) completed follow-up at 6 months. Intervention group participants had fewer symptoms than control group participants on the SSQ-14 (3.81; 95% CI, 3.28 to 4.34 vs 8.90; 95% CI, 8.33 to 9.47; adjusted mean difference, -4.86; 95% CI, -5.63 to -4.10; P .001; adjusted risk ratio [ARR], 0.21; 95% CI, 0.15 to 0.29; P .001). Intervention group participants also had lower risk of symptoms of depression (13.7% vs 49.9%; ARR, 0.28; 95% CI, 0.22 to 0.34; P .001). CONCLUSIONS AND RELEVANCE Among individuals screening positive for common mental disorders in Zimbabwe, LHW-administered, primary care-based problem-solving therapy with education and support compared with standard care plus education and support resulted in improved symptoms at 6 months. Scaled-up primary care integration of this intervention should be evaluated.