Cost-effectiveness and cost-benefit analysis of using methotrexate vs Goeckerman therapy for psoriasis. A pilot study.

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.