Comparing the Predictability of Different Diagnosis-Based Risk Adjusters to Individual Ambulatory Expenditures Under the National Health Insurance

• Main Authors: Chen-Kun Lin, 林振坤
• Other Authors: 張睿詒
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/21918926178957524261

碩士 === 國立臺灣大學 === 醫療機構管理研究所 === 94 === Background and purposes: Taiwan’s National Health Insurance has completely adopted a global budget payment system since 2002. In order to avoid the persistence of inefficiency and inequality, most developed countries adopting a prospective payment system has introduced some forms of risk-adjusted mechanism to refine the budget setting. This trend can be followed by Taiwan, especially setting the budget of outpatient care, which accounts for two thirds of total NHI’s expenditure. This study intends to compare the predictability of different diagnosis-based risk adjusters classified by ACGs, DCGs, and TASGs to individual outpatient expenditure. The results should provide insight into future development of indigenous risk adjusters and necessary modifications when foreign systems are introduced. Material and methods: Using the panel data 200,000 individuals compiled by the National Health Research Institutes (NHRI), 164,248 individuals who had a full three years of eligibility in 2000 to 2002 were selected as the study sample. All outpatient claimed data were collected. Diagnosis-based risk adjusters were classified through ACGs, DCGs, and TASGs using 2000 data, and these adjusters were employed to establish risk adjustment models and to predict the outpatient expenditures of 2001 and 2002. Least squares regression models were built with an estimation sample (one half of the total), and were then cross-validated with the validation sample (the other half of the total). Results: While the predictability of the ACG model are 9.44% and 10.25% for 2001 and 2002, the predictability of the DCG model are 37.36% and 32.71% for 2001 and 2002. The predictability of the TASG model are 36.78% and 36.05% for 2001 and 2002. Conclusion: Between the two foreign systems, DCGs outperforms ACGs in terms of predictability. The indigenous risk adjusters have similar predictability to that of DCGs. Nevertheless, the predictability of the indigenous risk adjusters is more stable than that of DCGs.