Newcomer R, Clay T, Luxenberg J S, Miller R H
Department of Social and Behavioral Science and the Institute for Health & Aging, University of California, San Francisco 94143-0612, USA.
J Am Geriatr Soc. 1999 Feb;47(2):215-9. doi: 10.1111/j.1532-5415.1999.tb04580.x.
Medicare claims as the basis for health condition adjustments is becoming a method of choice in capitation reimbursement. A recent study has found that claims-based beneficiary classification for Alzheimer's disease produces lower prevalence estimates and higher average costs than previous healthcare cost studies in this population. These sets of studies differ in data sources, period length, and in their specification of dementia.
Participants in the Medicare Alzheimer's Disease Demonstration (MADDE) provide a sample of persons known to have some form of dementia. This group is used to test the adequacy of claims data for identifying eligible cases and any bias in expenditure differences between those flagged or not flagged by a claim in a given period.
A prospective cohort design using up to 36 months of claims data.
The demonstration enrolled 4166 participants in treatment, and 3942 in a control group in eight communities across the US. Cases were combined in this analysis.
Persons with available Medicare Part A & B claims data: those receiving care under fee for service reimbursement were used in the analysis. A total of 5379 MADDE cases received fee for service care during 1991 and 1992, the period of primary interest in the analysis.
Client health and functional status interviews and Medicare Part A & B claims.
Less than 20% of MADDE participants were classified with Dementia of the Alzheimer type (DAT) from a single year of claims although 68% had a DAT diagnosis from a referring physician. Annualized expenditures were 1.7 times higher among those with DAT from claims compared with those known otherwise to have dementia but who had not been identified with this condition from Medicare claims.
Underclassification of dementia from claims records can be partially remedied by increasing the period during which claims are compiled, but additional diagnostic sources will likely be needed to increase prevalence counts closer to 100% of true cases. Risk adjustment based on a single year of reported claims expenditures may overpay providers, at least in the short term, because payment incentives will likely increase prevalence reporting.
将医疗保险理赔数据作为健康状况调整的依据正成为按人头付费报销的一种首选方法。最近一项研究发现，基于理赔数据对阿尔茨海默病进行受益人类别划分，与此前针对该人群的医疗费用研究相比，患病率估计值更低，平均成本更高。这些系列研究在数据来源、时间段长度以及痴呆症的界定方面存在差异。
医疗保险阿尔茨海默病示范项目（MADDE）的参与者提供了一个已知患有某种形式痴呆症的人群样本。该群体用于检验理赔数据在识别符合条件病例方面的充分性，以及在给定时间段内，被理赔标记或未被标记的人群在支出差异方面是否存在偏差。
采用前瞻性队列设计，使用长达36个月的理赔数据。
该示范项目在美国八个社区招募了4166名参与者接受治疗，3942名参与者作为对照组。本分析将病例合并。
拥有医疗保险A部分和B部分理赔数据的人群：分析中使用了那些接受按服务收费报销护理的人群。在1991年和1992年（分析的主要时间段），共有5379名MADDE病例接受了按服务收费的护理。
对客户健康和功能状况进行访谈，并收集医疗保险A部分和B部分的理赔数据。
尽管68%的MADDE参与者经转诊医生诊断患有阿尔茨海默型痴呆（DAT），但仅根据一年的理赔数据，被归类为DAT的参与者不到20%。与那些已知患有痴呆症但未被医疗保险理赔数据识别出患有该疾病的人相比，经理赔数据认定患有DAT的人的年化支出高出1.7倍。
通过延长理赔数据的收集时间段，可部分纠正理赔记录中痴呆症分类不足的问题，但可能还需要其他诊断来源，以使患病率计数更接近真实病例的100%。基于一年报告的理赔支出进行风险调整可能会使提供者获得超额支付，至少在短期内如此，因为支付激励措施可能会增加患病率报告。
