Importance: Approximately 1 in 5 adults are diagnosed with depression in their lifetime. However, less than half receive help from a health professional, with the treatment gap being worse for individuals with socioeconomic disadvantage. Computer-assisted cognitive behavioral therapy (CCBT) is an effective and convenient strategy to treat depression; however, its cost-effectiveness in a sociodemographically diverse population remains unknown.
Objective: To evaluate the cost-effectiveness of clinician-supported CCBT compared with treatment as usual (TAU) in a primary care population with a substantial number of patients with low income, limited computer or internet access, and lack of college education.
Design, setting, and participants: This economic evaluation was a randomized clinical trial-based cost-effectiveness analysis. The trial was conducted at the Departments of Family and Geriatric Medicine and Internal Medicine at the University of Louisville. Enrollment occurred from June 24, 2016, to May 13, 2019. Participants had mild to moderate depression and were followed up for 6 months after treatment completion. The last follow-up assessment was conducted on January 30, 2020. Statistical analysis was performed from August 2023 to August 2024.
Exposure: CCBT intervention was provided for 12 weeks and included 9 modules ranging from behavioral activation and cognitive restructuring to relapse prevention strategies, supported by telephonic sessions with a clinician, in addition to TAU, which included standard clinical management in primary care.
Main outcomes and measures: The primary health outcome was quality-adjusted life years (QALYs), estimated using the Short-Form 12 questionnaire (SF-12). The secondary outcome was treatment response, defined as at least 50% improvement in the Patient Health Questionnaire. The intervention cost included sessions with mental health clinicians and the cost of the CCBT software, plus the cost of loaner computer and internet data plan for low-resource households. An incremental cost-effectiveness ratio (ICER) was computed, while adjusting for baseline scores, age, and sex. The cost-effectiveness acceptability curve presented the probability of CCBT being cost-effective for a range of willingness-to-pay values.
Results: Among the 175 primary care patients included in this study, 148 (84.5%) were female; 48 (27.4%) were African American, 2 (1.2%) were American Indian or Alaska Native, 4 (2.5%) were Hispanic, 106 (60.5%) were White, and 15 (8.6%) were multiracial; and the mean (SD) age was 47.03 (13.15) years. CCBT was associated with better quality of life and higher chance of treatment response at the posttreatment and 6-month time points, compared with the TAU group. The ICER for CCBT was $37 295 (95% CI, $22 724-$66 546) per QALY, with a probability of 89.4% of being cost-effective at a willingness-to-pay threshold of $50 000/QALY. The ICER per case of treatment response was $3623 (95% CI, $2617-$5377).
Conclusions and relevance: In this trial-based economic evaluation, CCBT was found to be cost-effective, compared with TAU, in primary care patients with depression. As this study included individuals with low income and with limited internet access who are underrepresented in cost-effectiveness studies, it has important policy implications for addressing unmet needs in sociodemographically diverse populations.