Investigating societal determinants of oral health—Opportunities and challenges in multilevel studies

The high prevalence of oral diseases and the persistent nature of socioeconomic inequalities in oral health outcomes across societies presents a significant challenge for public health globally. A debate exists in epidemiology on the merits of investigating population variations in health and its determinants over studying individual health and its individual risk factors. The choice of analytical unit for health outcomes at the population level has policy implications and consequences for the causal understanding of population-level variations in health/disease. There is a lack of discussion in oral epidemiology on the relevance of studying population variations in oral health. Evidence on the role of societal factors in shaping variations in oral health at both the individual level and the population level is also mounting. Multilevel studies are increasingly applied in social epidemiology to address hypotheses generated at different levels of social organization, but the opportunities offered by multilevel approaches are less applied for studying determinants of oral health at the societal level. Multilevel studies are complex as they aim to examine hypotheses generated at multiple levels of social organization and require attention to a range of theoretical and methodological aspects from the stage of design to analysis and interpretation. This discussion study aimed to highlight the value in studying population variations in oral health. It discusses the opportunities provided by multilevel approaches to study societal determinants of oral health. Finally, it reviews the key methodological aspects related to operationalizing multilevel studies of societal determinants of oral health.