Meta-analysis and Meta-Regression Analyses Explaining Heterogeneity in Outcomes of Chronic Care Management for Depression: Implications for Person-Centered Mental Healthcare

Rationale, aims and objectives: Chronic care management programmes for depression show variation in effectiveness. This study aims to examine the clinical diversity and methodological heterogeneity related to the effectiveness of such programmes and to explain the heterogeneity in clinical outcomes. Objectives are to enable the understanding of and the decision-making about depression management programmes and to contribute to the implementation of chronic care management strategies for depression as part of advances in person-centered mental healthcare. Method: We performed a systematic review of reviews and empirical studies, including meta-analyses and meta-regression analyses on the most frequently reported outcomes. We explored to what extent the observed heterogeneity can be explained by study quality, length of follow-up, number of components of the Chronic Care Model (CCM) and patient characteristics. Results: Pooled effects of depression management programmes show significant improvement in treatment response (RR=1.38; p<0.05) and treatment adherence (RR=1.36; p<0.05). In meta-regression analysis, study quality and depression severity explain the substantial heterogeneity in respectively treatment response (36.6%; p=0.0352) and treatment adherence (88.7%; p=0.0083). Conclusions: The observed heterogeneity in depression outcomes cannot be explained by the number of intervention components and length of follow-up. Yet, the heterogeneity in treatment response can be explained partly by study quality, demonstrating the importance of good quality studies. Heterogeneity in treatment adherence can be explained partly by severity of the depression, indicating that taking account of depression severity contributes to maximising the effectiveness of chronic care management. Other potential sources of heterogeneity should be investigated to support informed decision-making on treating depression as a chronic condition as part of person-centered mental healthcare.