JMIR Publications

ABSTRACT

Background:

Major depressive disorder (MDD) is a leading cause of disability and death by suicide globally. Unguided Internet-based cognitive behavioral therapy (ICBT), with the promise to improve accessibility and affordability, has been proven effective for MDD. However, few studies have examined the cost-effectiveness of unguided ICBT for MDD in low-resource countries and under non-specialist routine care.

Objective:

This study aimed to evaluate the short- and long-term cost-utility of unguided ICBT compared to waiting-list control for persons suffering from MDD from the perspectives of society and healthcare system.

Methods:

This cost-utility analysis was implemented alongside an eight-week 2-arm pragmatic randomized controlled trial with a 12-month follow-up conducted in Shenzhen City, China. Outcomes including cost and health utility were collected at pre-treatment, post-treatment, 3, 6, and 12 months after the intervention. Both societal and healthcare system perspectives were adopted. Direct medical costs and indirect costs expressed in Chinese Yuan (CNY) were prospectively collected through the hospital information system and the Sheehan Disability Scale. Health outcome was measured by the Chinese version of SF-6D. The primary outcome was incremental cost-utility ratio (ICUR), expressed as the difference in costs between two therapies by the difference in quality-adjusted life years (QALYs). Seemingly unrelated regression and the bootstrap method were performed to estimate adjusted ICURs and the corresponding 95% confidence intervals (CI). Cost-effectiveness planes and cost-effectiveness acceptability curves were used to demonstrate the uncertainty. A series of scenario analyses were conducted to verify the robustness of base-case results.

Results:

A total of 244 participants with MDD were randomly allocated to the ICBT (n=122) or the waiting-list control (n=122) group. At pre-treatment, no statistical difference was observed in the aggregated cost and its components, and health utility between the two groups (P>.05). In the base-case analysis, the ICBT group reported higher direct medical costs (mean incremental costs (SE): 201.90 (1568.36) CNY) and better quality of life (mean incremental QALYs (SE): 0.0041 (0.0027)), while lower total costs (mean incremental costs (SE): ­899.45 (2064.49)) at post-treatment. The adjusted ICURs at post-treatment were respectively -194,720.38 (95% CI: -198,766.782, -190,673.981) and 49,700.33 (95% CI: 46,626.34, 52,774.31) CNY per QALY from societal and healthcare system perspectives, with the probability of unguided ICBT being cost-effective of 75.93% and 54.40% if the willingness-to-pay (WTP) was set at 1 time per capita gross domestic product. In scenario analyses, the probabilities respectively increased to 76.85% and 77.61%, indicating the potential of ICBT to be cost-effective over the long term.

Conclusions:

Unguided ICBT is a cost-effective treatment for MDD. This intervention not only helps patients with MDD to improve clinically but also generates societal savings. These findings provide the health economic evidence for a potential scalable MDD treatment method in developing countries. Clinical Trial: Chinese Clinical Trial Registry (ChiCTR2100046425); https://tinyurl.com/bdcrj4zv