Objective: To analyze the net benefit and cost-effectiveness of methotrexate use and Goeckerman therapy for psoriasis.
Design: Net benefit and cost-effectiveness depend on the costs, efficacy, and utilities of therapy. Utilities are quantitative measures of patient preferences. We obtained costs by using resource-based accounting techniques. Efficacy was estimated from literature reports. We surveyed patients with psoriasis, dermatologists, and healthy subjects using utility assessment methods. All assumptions were examined in a sensitivity analysis.
Main outcome measures: For net benefit, if benefits out-weighed the costs, it was deemed worth providing. For the cost-effectiveness analysis, the ratio of costs-to-effectiveness of less than $35,000 was considered cost-effective.
Results: Using utilities from healthy nonexperts, the costs of both therapies exceeded the benefits in mild and moderate psoriasis. In severe psoriasis, only methotrexate demonstrates a net benefit. Both therapies were cost-effective compared with no therapy. Liquid methotrexate should be chosen over the tablet form since it was cheaper and had the same outcome. Goeckerman was cost-effective against liquid methotrexate in severe, but not mild or moderate psoriasis. There was a trend for therapies to be more cost-effective when using patient utilities and less with dermatologist utilities. The results were highly sensitive to efficacy and utilities.
Conclusions: The results of this study need to be confirmed in other settings, but they demonstrate that the tools of cost-effectiveness and cost-benefit analysis have great potential value in dermatology. Once efficacy is better characterized and utilities better quantified, these types of analyses will be crucial for health care policy.