Short-term Clinical Outcomes and Implementation Insights: A Hybrid Cluster Randomized Controlled Trial of an "Add-On Online Mental Health Training" for Primary Care Doctors.

Background: Training primary care doctors (PCDs) enables them to provide timely and effective treatment of psychiatric disorders in community settings. However, its impact on clinical outcomes remains relatively unexplored. Methods: This cluster randomized controlled trial compared "Training As Usual" [TAU; 2 days of in-person, lecture-based training; control group (CG)] with TAU plus an 18.5-hour Online Mental Health Training (OMHT; study group [SG]) for PCDs. Clinical outcomes (n = 41; SG = 24, CG = 17) were assessed at baseline and after eight weeks using standardized scales (K10, EQ-5D-5L, IDEAS, CGI-S, BARS) across common (CMDs), severe (SMDs), and substance use disorders (SUDs, including alcohol and tobacco). Both groups completed questionnaires evaluating implementation aspects such as acceptability, adoption, appropriateness, feasibility, fidelity, and provided feedback on training relevance, changes in practice, and operational barriers. Results: Overall (all disorders put together), significant improvements in subjective perception of health and disease severity were found in both study (EQ-VAS, p < .01; CGI-S, p = .03) and CG (EQ-VAS, p < .01; CGI-S, p = .05), and a reduction in distress score (K10; p = .01) in SG alone. Domain-wise analysis showed significant improvements in K10 (p = .02), EQ-VAS (p = .04), and CGI-S (p = .04) scores only in SG for CMDs. The same was not true for SMDs or SUDs. PCDs reported high acceptability, adoption, and appropriateness (over 90%) for integrating mental health into primary care. However, feasibility (71.4-86.4% citing support systems) and fidelity (only 9% of consultations had psychiatric diagnoses, and just 25% of those received psychotropic prescriptions) were lower. Significant barriers included staff and medication shortages, stigma, and limited mental health awareness. Conclusions: Training PCDs has the potential to yield significant short-term clinical benefits for individuals with common psychiatric disorders. Supplementary training may provide additional clinical advantages, particularly for CMDs. PCDs identified multiple challenges in incorporating mental health services into primary care practice. Trial Registration: The Clinical Trial Registry of India (Registration No. CTRI/CTRI/2024/02/062906.