Fowles J B, Weiner J P, Knutson D, Fowler E, Tucker A M, Ireland M
Health Research Center, Institute for Research and Education, HealthSystem Minnesota, Minneapolis 55416, USA.
JAMA. 1996;276(16):1316-21.
To compare performance of different health status measures for risk-adjusting capitation rates.
Cross-sectional study. Health status measures derived from 1 year were used to predict resources for that year and the next.
Group-network health maintenance organization in Minnesota.
Sample of 18- to 64-year-old (n=3825) and elderly (aged > or = 65 years; n=1955) members enrolled in a network-model health maintenance organization in Minnesota.
Total expenditures in the year concurrent with the health status survey (July 1991 through June 1992) and total expenditures in the year following the survey (July 1992 through June 1993).
Capitation adjustment based on demographic measures performed least well. Both self-reported health status measures and diagnoses predicted future expenditures twice as well as demographics. When predicting costs for groups of patients rather than individuals, the demographic model worked well for average groups but tended to overpredict healthier groups and underpredict sicker groups. Ambulatory Care Groups based on diagnoses performed better than self-reported health status both in the retrospective models and across healthier and sicker groups.
Without risk adjustment, capitation rates are likely to overpay or underpay physicians for certain patient groups. It is possible to improve prediction using health status measures for risk adjustment. When selection bias is suspected and administrative data are available, we recommend a risk-adjustment method based on diagnostic information. If diagnostic data are not available, we recommend a system based on simple self-reported measures, such as chronic conditions, rather than complex functional status measures.
比较不同健康状况测量方法在风险调整人头费率方面的表现。
横断面研究。使用从1年中得出的健康状况测量方法来预测当年及次年的资源使用情况。
明尼苏达州的团体网络健康维护组织。
明尼苏达州一个网络模式健康维护组织中18至64岁（n = 3825）和老年人（年龄≥65岁；n = 1955）的成员样本。
健康状况调查同期（1991年7月至1992年6月）的总支出以及调查后一年（1992年7月至1993年6月）的总支出。
基于人口统计学测量方法的人头费调整表现最差。自我报告的健康状况测量方法和诊断对未来支出的预测能力是人口统计学方法的两倍。在预测患者群体而非个体的费用时，人口统计学模型对平均群体效果良好，但往往对健康群体预测过高，对患病群体预测过低。在回顾性模型以及健康和患病群体中，基于诊断的门诊护理组的表现均优于自我报告的健康状况。
如果不进行风险调整，人头费率可能会对某些患者群体向医生支付过多或过少的费用。使用健康状况测量方法进行风险调整有可能改善预测。当怀疑存在选择偏倚且有行政数据可用时，我们推荐基于诊断信息的风险调整方法。如果没有诊断数据，我们推荐基于简单自我报告测量方法（如慢性病）的系统，而非复杂的功能状态测量方法。
