Health Governance Review Volume 31, Issue 1

Club convergence in healthcare expenditure in the United StatesThe aim of the article under review (Ogundari and Obembe, 2026) was to revisit the disparities in per capita healthcare expenditure and prescription drug spending over time across the 50 US states and the District of Columbia (the previous research in the US included data till 2014).The authors have chosen this methodological approach as "the convergence hypothesis provides important frameworks for examining how economic indicators (e.g.healthcare expenditure, income inequality, life expectancy and healthcare spending) converge across regions, cities, states or countries over time" (Ogundari and Obembe, 2026).The authors explain their choice of the club convergence test over other methods like β-convergence, γ-convergence and unit root/cointegration tests "because it can handle transitional heterogeneity and allows for the possibility of multiple steady equilibria" (Ogundari and Obembe, 2026).The results of the article under review "reveal widening disparities in per capita healthcare expenditure and prescription drug spending across US states and the District of Columbia, [. ..] per capita healthcare expenditure exhibits two convergence clubs and one divergence group.In comparison, per capita prescription drug spending exhibits three convergence clubs" (Ogundari and Obembe, 2026).When comparing their results with previous findings in the US (where other methods were used), the authors found that "all these studies provide evidence supporting divergence (or lack of full convergence) in healthcare spending" that is consistent with their results: "the implication is that a single pattern of behavior does not exist in healthcare expenditure dynamics across the US states, which shows a widening disparity" (Ogundari and Obembe, 2026).The authors conclude that "these studies (Panopoulou and Pantelidis, 2013; Clemente et al., 2019a) also revealed evidence that shows healthcare expenditure across US states eventually converging into two distinct convergence clubs, where the disparity in healthcare expenditure decreases over time.This finding is also consistent with the results of the present study" (Ogundari and Obembe, 2026).The authors of the article under review conclude that "policies that affect social determinants of health services across the population, such as investment in public health infrastructure, poverty, lack of education, unemployment, etc., should be pursued" (Ogundari and Obembe, 2026).Though widely applied in health research across diverse geographic contexts, club convergence tests have fundamental methodological and interpretive challenges.Convergence analyses can precisely describe club structures and identify club membership patterns, yet often fail to provide clear policy guidance: recent studies recommended "targeted interventions" or "club-specific policies" underscored a need for common health policies for the different convergence clubs, while country-specific policies should be implemented for the divergent countries, but did not specify what these should entail beyond the observation that one-size-fits-all approaches are insufficient (Nag et al., 2023; Clemente et al., 2019b;Ndzignat Mouteyica and Ngepah, 2024).Convergence testing can identify that regions and/or IJHG 31,1