Abstract
OBJECTIVE: To determine the consequences of the Gobeille v. Liberty Mutual Supreme Court decision on the representativeness of the Massachusetts all-payer claims database (APCD). The loss of individuals captured in the APCD may vary demographically, geographically, and in the capture of fatal opioid-related overdose (OOD). DATA SOURCES AND STUDY SETTING: We used 2013-2021 data from the Massachusetts Public Health Data Warehouse (PHD), which links person-level APCD records to other datasets. The APCD includes commercially-insured health claims mandatorily reported pre-Gobeille. Post-Gobeille, reporting from self-insured plans, a subset of commercially-insured plans, became voluntary. STUDY DESIGN: In a repeated cross-sectional design, we compared the APCD population characteristics in 2015 to each subsequent year 2016-2021. DATA COLLECTION/EXTRACTION METHODS: We compared pre-post Gobeille statewide APCD demographic distributions using standardized mean differences and assessed geographic distribution changes by ZIP Code. We identified fatal OOD using death certificates. We used annual and monthly interrupted time-series models with publicly-available state records as the control to quantify the pre- (2013-2015) and post- (2016-2021) Gobeille changes in the total APCD population and in fatal OOD when linked to the APCD within the PHD. PRINCIPAL FINDINGS: Within APCD, the commercially-insured population decreased by 38% post-Gobeille. State-level age increased slightly and sex distributions remained stable, while proportions of White non-Hispanic individuals decreased. Suburban ZIP Codes had the highest losses of individuals. In 2021, under 80% of fatal OODs could be linked to the APCD, compared to 95% linkage pre-Gobeille. The change in monthly fatal OOD rates when linked to the APCD was 0.55 persons higher per 100,000 people post-Gobeille (95% CI: 0.05, 1.05) than the change observed in official statistics. CONCLUSIONS: The Gobeille decision negatively impacted APCD geographic and racial representativeness in Massachusetts, which should be addressed to improve external validity in Massachusetts and other states using APCDs to assess health services.