Does the Health System Model Shape Prevention? Evidence from 22 OECD Countries (2004-2023)

In an era in which population ageing, rising healthcare costs and growing global health challenges are pressing global issues, the main aim of our article is to analyze trends in preventive care expenditures from 2004 to 2023 in 22 European countries, examining whether specific health systems are associated with different time trends in preventive care expenditures over the considered time. Although there are few studies investigating this issue adopting the standard tripartite classification, to our knowledge, this is the first study to explore the topic using the latest classification of healthcare systems proposed by Bohm. We performed a time trend analysis using secondary data from 22 European OECD countries during a twenty-year period (2004-2023); in addition, a hierarchical semi-log polynomial mixed-effects regression analysis has been performed, including annual country-level % preventive expenditures in association with the three structural dimensions -- regulation, financing and provision -- according to Bohms classification as explanatory variables. Our results indicate that, in terms of compound annual rate, most countries exhibited an increase in % of preventive expenditures (between 0.2% and 3.7%), while seven countries denounced a decrease (between -6.3% and -0.2%) during the considered period. The regression analysis shows that the trend of % preventive expenditures did not differ in two of the three dimensions under study: financing and provision. In contrast, in countries with statal regulation, the curvilinear trend was more pronounced than in countries with statal regulation (b=0.0035; 95% CI= 0.0013, 0.0057). In conclusion, there is no correlation between the type of healthcare system and the share of expenditure allocated to prevention activities in the countries analysed; a resulting implication is that investment in prevention is not intrinsically determined by the organisational structure of the healthcare system, but responds to external factors. Key questionsO_ST_ABSWhat is already known on this topic?C_ST_ABSPreventive care represents a relatively small share of total health expenditure in most OECD countries, despite its recognized importance in addressing public health issues. Previous studies attempted to explore cross-country differences in preventive spending and the potential role of healthcare system organization, often using traditional classifications (e.g., Beveridge or Bismarck). However, evidence remains limited and no studies have examined long-term trends using current multidimensional classifications of healthcare systems. What does this study add?By analyzing trends in preventive care expenditures over a twenty-year period across 22 European OECD, our study showed trends in the share of spending on prevention were largely independent of the structural characteristics of healthcare systems. Among the analyzed dimensions, only the regulation showed a more pronounced curvilinear trend in countries with societal regulation. How this study might affect research, practice or policy?Since the findings suggest that investment in prevention may depend more on contextual factors such as political priorities and public health strategies rather than structural characteristics of healthcare systems, policymakers should therefore promote prevention through targeted policy commitment instead of relying on health system design alone.