Comparison of Approaches for Aggregating Quality Measures in Population-based Payment Models.

OBJECTIVE: To assess the impact of alternative methods of aggregating individual quality measures on Accountable Care Organization (ACO) overall scores. DATA SOURCE: 2014 quality scores for Medicare ACOs. STUDY
DESIGN: We compare ACO overall scores derived using CMS' aggregation approach to those derived using alternative approaches to grouping and weighting measures. PRINCIPAL
FINDINGS: Alternative grouping and weighting methods based on statistical criteria produced overall quality scores similar to those produced using CMS' approach (κ = 0.80 to 0.95). Scores derived from giving specific domains greater weight were less similar (κ = 0.51 to 0.93).
CONCLUSIONS: How measures are grouped into domains and how these domains are weighted to generate overall scores can have important implications for ACO's shared savings payments. © Health Research and Educational Trust.