Equity Meets Primary-Care-Sensitive Performance: A Longitudinal Benchmark of Cost-Related Unmet Care and Avoidable Hospitalization in Europe

Background/Objectives: This study compares European health systems by considering the cost-related unmet-care inequality between income groups and primary-care-sensitive avoidable hospitalizations. Methods: This was a longitudinal comparative benchmarking study. The main sample consists of 275 country-year observations from 20 European countries with at least ten years of data during 2009–2023. The first dimension is measured by the absolute difference between the lowest and highest income quintiles in the prevalence of unmet medical examination or treatment because it was too expensive. The second dimension uses age- and sex-standardized avoidable hospitalization rates for asthma, chronic obstructive pulmonary disease, congestive heart failure, and diabetes. The 20-country core sample was defined before within-year rank normalization. The indicators were converted into rank scores on a scale of 0–1 within each annual comparison set, with equal weighting for both dimensions. Temporal uncertainty in country rankings was examined using a three-year synchronized moving-block bootstrap with 10,000 iterations. Results: In the main comparison, the Netherlands, Slovenia, Spain, Sweden, and Finland ranked in the top five. The Netherlands and Slovenia remained in the top five in all valid bootstrap replications; the corresponding probabilities were 99.90% for Spain, 90.67% for Sweden, and 95.66% for Finland. Top-five membership nevertheless changed under some alternative weighting, disease-omission, scaling, and balanced-period specifications. In the spending-adjusted assessment, each country was compared based on a nonlinear spending–performance relationship established from other countries, without including its own observations in the estimation equation; Slovenia, the Netherlands, and Spain took the top three positions. Conclusions: The findings should be interpreted not as a definitive country ranking, but as a relative assessment of health systems that highlights the differences between health inequality, primary care-sensitive outcomes, and resource intensity.