Redaction of Substance Abuse Claims in Medicare Research Files Affects Spending Outcomes for Nearly One in Five Beneficiaries with Serious Mental Illness
研究发现，医疗保险索赔数据中药物滥用记录的删减导致近20%严重精神疾病患者的支出估算出现偏差，其中A部分支出被低估57%，提醒研究者注意数据删减带来的偏倚。
OBJECTIVE: To assess the impact of substance abuse claims redaction on Medicare spending estimates for beneficiaries with serious mental illness. DATA SOURCES: The 2012 claims and unredacted beneficiary-level Medicare spending totals from CMS's Chronic Conditions Warehouse. STUDY DESIGN: We identified beneficiaries with claims affected by the redaction by comparing claims-based spending estimates to unredacted spending totals. Differences in characteristics of beneficiaries with and without redacted claims were examined in bivariate analyses. PRINCIPAL FINDINGS: Claims-based spending totals differed from unredacted totals for 19.7 percent of the cohort. Part A spending for those with redacted claims was underreported by 57.0 percent. Characteristics of beneficiaries with and without redacted claims differed significantly. CONCLUSIONS: Researchers who rely on Medicare claims to analyze spending outcomes for beneficiaries with serious mental illness should be aware of the potential for bias due to nonrandom redaction of substance abuse data.