The impact of differences in EQ-5D and SF-6D utility scores on the acceptability of cost-utility ratios: results across five trial-based cost-utility studies.

OBJECTIVE: This article investigates whether differences in utility scores based on the EQ-5D and the SF-6D have impact on the incremental cost-utility ratios in five distinct patient groups. METHODS: We used five empirical data sets of trial-based cost-utility studies that included patients with different disease conditions and severity (musculoskeletal disease, cardiovascular pulmonary disease, and psychological disorders) to calculate differences in quality-adjusted life-years (QALYs) based on EQ-5D and SF-6D utility scores. We compared incremental QALYs, incremental cost-utility ratios, and the probability that the incremental cost-utility ratio was acceptable within and across the data sets. RESULTS: We observed small differences in incremental QALYs, but large differences in the incremental cost-utility ratios and in the probability that these ratios were acceptable at a given threshold, in the majority of the presented cost-utility analyses. More specifically, in the patient groups with relatively mild health conditions the probability of acceptance of the incremental cost-utility ratio was considerably larger when using the EQ-5D to estimate utility. While in the patient groups with worse health conditions the probability of acceptance of the incremental cost-utility ratio was considerably larger when using the SF-6D to estimate utility. CONCLUSIONS: Much of the appeal in using QALYs as measure of effectiveness in economic evaluations is in the comparability across conditions and interventions. The incomparability of the results of cost-utility analyses using different instruments to estimate a single index value for health severely undermines this aspect and reduces the credibility of the use of incremental cost-utility ratios for decision-making.

Cost-effectiveness of a nurse-led telemonitoring intervention based on peak expiratory flow measurements in asthmatics: results of a randomised controlled trial.

BACKGROUND: Asthma is a chronic lung disease in which recurrent asthma symptoms create a substantial burden to individuals and their families. At the same time the economic burden associated with asthma is considerable. METHODS: The cost-effectiveness study was part of a single centre prospective randomised controlled trial comparing a nurse-led telemonitoring programme to usual care in a population of asthmatic outpatients. The study included 109 asthmatic outpatients (56 children; 53 adults). The duration of follow-up was 12 months, and measurements were performed at baseline, 4, 8, and 12 months. Patients were asked to transfer their monitor data at least twice daily and by judging the received data and following a stepwise intervention protocol a nurse was able to act as the main caregiver in the intervention group. In both groups the EQ-5D and the SF-6D were used to obtain estimates of health state utilities. One year health care costs, patient and family costs, and productivity losses were calculated. The mean incremental costs were weighted against the mean incremental effect in terms of QALY. RESULTS: The study population generally represented mild to moderate asthmatics. No significant differences were found between the groups with regard to the generic quality of life. Overall, the mean health care costs per patient were higher in the intervention group than in the control group. The intervention costs mainly caused the cost difference between the groups. The intervention costs the society euro 31,035/QALY gained with regard to adults and with regard to children euro 59,071/QALY gained. CONCLUSION: If the outcome is measured by generic quality of life the nurse-led telemonitoring programme is of limited cost-effectiveness in the study population. From the societal perspective the probability of the programme being cost-effective compared to regular care was 85% at a ceiling ratio of euro 80,000/QALY gained among the adults and 68% among the children. A decrease in the price of the asthma monitor will substantial increase the probability of the programme to be cost-effective.

Cost-effectiveness of self-management in asthma: a systematic review of peak flow monitoring interventions.

OBJECTIVES: It is generally accepted that home peak flow monitoring increases patients' self-management and could lead to cost savings. The aim of this review was to analyze costs and the cost-effectiveness of self-management based on peak flow monitoring interventions in asthma. METHODS: Twenty-one studies were included in this review. Data were extracted, and methodological and economic quality were assessed. These studies presented economic information regarding self-management interventions based on peak flow monitoring in asthmatics. The mean methodological quality was 4.6 (maximum 8), and the mean economic quality was 12.0 (maximum 15). RESULTS: In eighteen studies, the interventions led to net savings compared with usual care or less intensive intervention. Only three studies found the total costs to be higher in the intervention group. In thirteen of the seventeen studies that analyzed health outcomes, at least one of the reported health outcomes improved statistically significantly after the intervention. However, the methods of economic evaluation differed among the studies and were not always in line with the standard methodology. CONCLUSIONS: The interventions, costs, and outcomes were very diverse. The results emphasize the need for guidelines to increase the comparability of cost-effectiveness evaluations relating to asthma. Only then will it be possible to conclude whether interventions for asthmatics, such as self-management based on peak flow monitoring interventions, are cost-effective.