Does Conventional Cost-Effectiveness Analysis Disadvantage Treatments for Severe Disease? Evidence From US Value Assessments.

Abstract

Objectives: This study aimed to assess how frequently quality-adjusted life-year (QALY)-based and life-year (LY)-based incremental health benefits meaningfully differ and whether those differences affect cost-effectiveness conclusions; how these differences vary across disease categories and what disease severity composition underlies this variation; and whether the QALY-LY difference is associated with baseline disease severity.

Methods: We analyzed 167 treatment-comparator assessment pairs from 71 Institute for Clinical and Economic Review reports (2017-2025), spanning 65 conditions across eight disease categories. We compared incremental QALYs and LYs, assessed cost-effectiveness concordance at $100 000 and $150 000 thresholds, and examined cross-category variation. In a restricted sample of 82 pairs, we assessed associations between severity measures and the QALY-LY difference using linear regression and Spearman rank correlation.

Results: QALYs showed greater incremental gains than LYs in 59% of assessments; LYs were greater in 22%. Cost-effectiveness conclusions were highly concordant (92.2% at $100 000; 87.4% at $150 000), although QALYs classified 20% to 32% more interventions as cost-effective. The QALY-LY difference varied significantly across disease categories (P < .001), reflecting differences in disease burden composition. Neither LY lost nor equal-value of LYs lost was meaningfully associated with the QALY-LY difference. The only significant association emerged for baseline health-related quality of life under standard care, where greater impairment was associated with larger incremental gains in QALYs relative to LYs. Both metrics scaled proportionally with disease severity.

Conclusions: QALY-based cost-effectiveness does not systematically disadvantage treatments for more severe diseases. Replacing QALYs with LYs would omit the therapeutic value most relevant to high-morbidity populations, potentially working against the interests of the patient populations that this policy debate seeks to protect.