Economic evaluation of schema therapy and clarification-oriented psychotherapy for personality disorders: a multicenter, randomized controlled trial

Purpose: To compare from a societal perspective the cost-effectiveness and cost-utility of schema therapy, clarification-oriented psychotherapy, and treatment as usual for patients with avoidant, dependent, obsessive-compulsive, paranoid, histrionic, and/or narcissistic personality disorder. Method: A multicenter, randomized controlled trial, single-blind parallel design, was conducted between May 2006 and December 2011 in 12 Dutch mental health institutes. Data from 320 patients (diagnosed according to DSM-IV criteria) randomly assigned to schema therapy (n = 145), treatment as usual (n = 134), or clarification-oriented psychotherapy (n = 41) were analyzed. Costs were repeatedly measured during 36 months by interview and patient registries. Primary outcome measures were proportion of recovered patients as measured with the Structured Clinical Interview for DSM-IV Axis II Personality Disorders for the cost-effectiveness analysis, and quality-adjusted life-years (QALYs) for the cost-utility analysis. Bootstrap replications in the cost-effectiveness and the cost-utility planes were used to estimate the probability that one treatment was more cost-effective than the other. Mixed gamma regression on net monetary benefit for different levels of willingness to pay for extra effects was used as sensitivity analysis. Additional sensitivity analyses were done to assess robustness of the results. Results: Due to higher clinical effects and lower costs, schema therapy was dominant over the other treatments in the cost-effectiveness analyses. Schema therapy has the probability of being the most cost-effective treatment (78% at (sic)0 to 96% at (sic)37,500 [$27,375] willingness to pay per extra recovery). Treatment as usual was more cost-effective than clarification-oriented psychotherapy due to lower costs. In the cost-utility analysis, schema therapy had a stable 75% probability of being cost-effective. Sensitivity analyses confirmed these findings. Conclusions: The results support the cost-effectiveness of schema therapy but not of clarification-oriented psychotherapy. Trial Registration: Netherlands Trial Register NTR566