Patient Variability Seldom Assessed in Cost-effectiveness Studies.

Area of Science:

• Health Economics
• Decision Science
• Public Health

Background:

• Cost-effectiveness analysis (CEA) estimates can significantly differ across patient subgroups due to variations in preferences, risks, effectiveness, life expectancy, and costs.
• No systematic review has comprehensively assessed the frequency and impact of subgroup analyses in CEA.

Purpose of the Study:

• To determine the frequency of subgroup analyses in CEA.
• To identify the types of heterogeneity addressed by these subgroup analyses.
• To assess how often subgroup heterogeneity influences cost-effectiveness conclusions relative to conventional thresholds.

Main Methods:

• A review of 200 randomly selected cost-utility analyses from the Tufts Medical Center CEA Registry (published through 2016).
• Ascertainment of whether studies reported subgroup results and collection of data on subgroup characteristics.
• Identification of whether subgroup results crossed conventional cost-effectiveness benchmarks (e.g., $100,000 per QALY).

Main Results:

• 19% of studies reported patient subgroup results.
• Subgroup analyses were more common in US-based, government-funded studies focusing on primary or secondary prevention.
• Age was the most common stratification characteristic; 13 out of 23 reported subgroup ratios in US studies crossed conventional benchmarks.

Conclusions:

• The majority of CEAs do not report subgroup results, with age being the most frequent stratification factor.
• Over half of reported subgroup analyses could lead to different value-based healthcare decisions for specific patient groups.