Cost variation in diabetes care across Dutch care groups?

Objective The introduction of bundled payment for diabetes care in the Netherlands led to the origination of care groups. This study explored to what extent variation in health care costs per patient can be attributed to the performance of care groups. Furthermore, the commonly applied simple mean aggregation was compared with the more advanced generalized linear mixed model (GLMM) to benchmark health care costs per patient between care groups. Data Source Dutch 2009 nationwide insurance claims data of diabetes type 2 patients (104,544 patients, 50 care groups). Study Design Both a simple mean aggregation and a GLMM approach was applied to rank care groups, using two different health care costs variables: total treatment health care costs and diabetes-specific specialist care costs per diabetes patient. Principal Findings Care groups varied slightly in the first and mainly in the second indicator. Care group variation was not explained by composition. Although the ranking methods were correlated, some care groups’ rank positions differed, with consequences on the top-10 and the low-10 positions. Conclusions Differences between care groups exist when an appropriate indicator and a sophisticated aggregation technique is used. Currently applied benchmarking may have unfair consequences for some care groups

Verschillen zorgkosten tussen zorggroepen?: Vergelijking van zorggroepen voor mensen met diabetes

Objective: Is the simple mean of the costs per diabetes patient a suitable tool with which to compare care groups? Do the total costs of care per diabetes patient really give the best insight into care group performance? Design: Cross-sectional, multi-level study. Method: The 2009 insurance claims of 104,544 diabetes patients managed by care groups in the Netherlands were analysed. The data were obtained from Vektis care information centre. For each care group we determined the mean costs per patient of all the curative care and diabetes-specific hospital care using the simple mean method, then repeated it using the 'generalized linear mixed model'. We also calculated for which proportion the differences found could be attributed to the care groups themselves. Results: The mean costs of the total curative care per patient were €3,092 - €6,546; there were no significant differences between care groups. The mixed model method resulted in less variation (€2,884 - €3,511), and there were a few significant differences. We found a similar result for diabetes-specific hospital care and the ranking position of the care groups proved to be dependent on the method used. The care group effect was limited, although it was greater in the diabetes-specific hospital costs than in the total costs of curative care (6.7% vs. 0.4%). Conclusion: The method used to benchmark care groups carries considerable weight. Simply stated, determining the mean costs of care (still often done) leads to an overestimation of the differences between care groups. The generalized linear mixed model is more accurate and yields better comparisons. However, the fact remains that 'total costs of care' is a faulty indicator since care groups have little impact on them. A more informative indicator is 'costs of diabetes-specific hospital care' as these costs are more influenced by care groups