Paper short abstract:

The study compared the OxCAP-MH and SWB measures for assessing quality of life in Ugandan PLWH with depression. Results indicate that combining both instruments offers a comprehensive assessment of interventions, with potential applications in global mental health research for chronic conditions.

Paper long abstract:

Globally, 31% of people living with HIV (PLWH) suffer from depressive disorders (DD). The HIV+D study, a cluster-randomized trial, sought to assess the effectiveness of integrating managed care of DD in people receiving routine HIV care in Uganda. This study addresses the gap in assessing quality of life for PLWH with comorbid depression by comparing two assessment instruments: the capabilities approach-based Oxford CAPabilities Questionnaire for Mental Health (OxCAP-MH) and subjective wellbeing (SWB) measures.

1115 PLWH and depression from 40 HIV clinics in Uganda participated in this study. Self-reported data on OxCAP-MH and SWB were collected at baseline, 3 months, and 12 months. Concordance correlation coefficient (CCC) and Spearman's correlation coefficient were used to assess agreement and validity, respectively.

The CCC of 0.331 (95% CI, 0.279 – 0.384; P<0.001) indicates a moderate level of agreement between OxCAP-MH and the life satisfaction dimension. The standard error (SE=0.027) associated with the CCC implies that the CCC estimate is precise. The Pearson correlation coefficient indicates a moderate positive correlation (r=0.331). The Bland-Altman analysis suggests a small average difference of -0.002 (95% CI, -2.269 - 2.265) between OxCAP-MH and the life satisfaction dimension with a reduced major axis (RMA) slope of 1 that indicates accuracy in the agreement due to the proportional relationship of the variables. There is a moderate and statistically significant convergent validity (r=0.330; P<0.001).

The CCC of 0.287 (95% CI, 0.233 – 0.342; P<0.001) indicates a weak level of agreement between OxCAP-MH and the happiness dimension. The Pearson correlation coefficient (r=0.287) and the CCC are both statistically significant (P<0.001). The average difference between OxCAP-MH and the happiness dimension from the Bland-Altman analysis is -0.001, with a standard deviation of 1.193 (95% CI, -2.340-2.338). The slope of the RMA line indicates accuracy and precision in the agreement (slope=1). There is a weak but statistically significant positive convergent validity (r=0.264; P<0.001).

The results suggest that, while OxCAP-MH and SWB capture related constructs, they likely tap into distinct aspects of quality of life in PLWH and depression. This aligns with their theoretical underpinnings. OxCAP-MH, grounded in the capabilities approach, assesses individuals' opportunities, while SWB measures directly capture individuals' evaluations, reflecting their emotional state and overall life satisfaction. This distinction highlights the potential benefits of employing both instruments to capture more dimensions of life quality and wellbeing. OxCAP-MH provides insights into capabilities, which might not be directly reflected in subjective reports of wellbeing.