Economic evaluations and randomized trials in spinal disorders: principles and methods.

STUDY DESIGN: Descriptive methodologic recommendations. OBJECTIVE: To help researchers designing, conducting, and reporting economic evaluations in the field of back and neck pain. SUMMARY OF BACKGROUND DATA: Economic evaluations of both existing and new therapeutic interventions are becoming increasingly important. There is a need to improve the methods of economic evaluations in the field of spinal disorders. MATERIALS AND METHODS: To improve the methods of economic evaluations in the field of spinal disorders, this article describes the various steps in an economic evaluation, using as example a study on the cost-effectiveness of manual therapy, physiotherapy, and usual care provided by the general practitioner for patients with neck pain. RESULTS: An economic evaluation is a study in which two or more interventions are systematically compared with regard to both costs and effects. There are four types of economic evaluations, based on analysis of: (1) cost-effectiveness, (2) cost-utility, (3) cost-minimization, and (4) cost-benefit. The cost-utility analysis is a special case of cost-effectiveness analysis. The first step in all these economic evaluations is to identify the perspective of the study. The choice of the perspective will have consequences for the identification of costs and effects. Secondly, the alternatives that will be compared should be identified. Thirdly, the relevant costs and effects should be identified. Economic evaluations are usually performed from a societal perspective and include consequently direct health care costs, direct nonhealth care costs, and indirect costs. Fourthly, effect data are collected by means of questionnaires or interviews, and relevant cost data with regard to effect measures and health care utilization, work absenteeism, travel expenses, use of over-the-counter medication, and help from family and friends, are collected by means of cost diaries, questionnaires, or (telephone) interviews. Fifthly, real costs are calculated, or the costs are estimated on the basis of real costs, guideline prices, or tariffs. Finally, in the statistical analysis the mean direct, indirect, and total costs of the alternatives are compared, using bootstrapping techniques. Incremental cost-effectiveness ratios are graphically presented on a cost-effectiveness plane and acceptability curves are calculated. CONCLUSION: Economic evaluations require specific methods. These recommendations may be helpful in improving the quality of economic evaluations of new and existing therapeutic interventions in the field of spinal disorders.

Costs of treating bleeding and perforated peptic ulcers in The Netherlands.

OBJECTIVE: Gastrointestinal toxicity of nonsteroidal antiinflammatory drugs includes perforations and bleeds. Several preventive strategies are being tested for cost-effectiveness, but little is known about the costs of the complications they are trying to prevent. We estimated the direct costs of hospital treatment of bleeding and perforated ulcers in a university hospital, from data in discharge letters and the hospital management information system. METHODS: Eligible patients had been treated in the VU University Medical Center between January 1997 and August 2000 for an ulcer bleed or perforation (International Classification of Diseases code 531-4). Resource use comprised hospitalization days and diagnostic and therapeutic interventions. Insurance claim prices determined the costs from the payers' perspective. In a secondary analysis we excluded resource use that was clearly related to the treatment of comorbid illness. RESULTS: Fifty-three patients with a bleeding (n = 35) or perforated ulcer (n = 15) or both (n = 3) were studied, including 14 with comorbidity; 22 complications occurred in the stomach, 29 in the duodenum, one in both stomach and duodenum, and one after partial gastrectomy. A simultaneous bleed and perforation was most expensive (26,000 euro), followed by perforation (19,000 euro) and bleeding (12,000 euro). A bleed in the duodenum was more expensive than in the stomach (13,000 euro vs 10,000 euro), while the opposite was seen for perforations (13,000 euro vs 21,000 euro). Comorbidity increased costs substantially: even after correction for procedures unrelated to the ulcer complication, comorbidity more than doubled the costs of treatment. CONCLUSION: Treatment of complicated ulcers is expensive, especially in patients with comorbid conditions.

Cost effectiveness and cost utility of acetylcysteine versus dimethyl sulfoxide for reflex sympathetic dystrophy.

OBJECTIVE: To determine the cost effectiveness and cost utility of acetylcysteine versus dimethyl sulfoxide (DMSO) for patients with reflex sympathetic dystrophy (RSD), from a societal viewpoint. DESIGN: An economic evaluation was conducted alongside a double-dummy, double-blind, randomised, controlled trial. Patients were followed for 1 year. The primary outcome measure was the Impairment-level Sum Score (ISS). Utilities were determined by the EuroQOL instrument (EQ-5D). Both cost-effectiveness and cost-utility analyses were performed. Differences in mean direct, indirect and total costs were estimated. Corresponding 95% confidence intervals were calculated by bootstrapping techniques. RESULTS: Both groups (DMSO, n = 64; acetylcysteine, n = 67) showed relevant improvement; no differences in effects were found. Only the total direct costs were significantly lower in the DMSO group for the period of 0-52 weeks. The incremental cost-effectiveness ratios showed that, in general, DMSO generated fewer costs and more effects compared with acetylcysteine. Post-hoc subgroup analyses on cost effectiveness suggested that patients with warm RSD could be best treated with DMSO and patients with cold RSD with acetylcysteine. These results were based on small subsamples. CONCLUSION: In general, DMSO is the preferred treatment for patients with RSD.