Education and Self-Reported Health: Evidence from 23 Countries on the Role of Years of Schooling, Cognitive Skills and Social Capital

RESEARCH ARTICLE Education and Self-Reported Health: Evidence from 23 Countries on the Role of Years of Schooling, Cognitive Skills and Social Capital Francesca Borgonovi1☯*, Artur Pokropek2☯ 1 Department for Education and Skills, Organisation for Economic Co-operation and Development (OECD), Paris, France, 2 Institute of Philosophy and Sociology, Polish Academy of Science, Warsaw, Poland ☯ These authors contributed equally to this work. * Abstract OPEN ACCESS Citation: Borgonovi F, Pokropek A (2016) Education and Self-Reported Health: Evidence from 23 Countries on the Role of Years of Schooling, Cognitive Skills and Social Capital. PLoS ONE 11(2): e0149716. doi:10.1371/journal.pone.0149716 Editor: Joshua L Rosenbloom, Iowa State University, UNITED STATES Received: July 12, 2015 Accepted: February 4, 2016 Published: February 22, 2016 Copyright: © 2016 Borgonovi, Pokropek. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: PIAAC data can be downloaded for free at http://www.oecd.org/site/piaac/ publicdataandanalysis.htm. Funding: The authors have no support or funding to report. Competing Interests: The authors have declared that no competing interests exist. We examine the contribution of human capital to health in 23 countries worldwide using the OECD Survey of Adult Skills, a unique large-scale international assessment of 16–65 year olds that contains information about self-reported health, schooling, cognitive skills and indicators of interpersonal trust, which represents the cognitive dimension of social capital. We identify cross-national differences in education, skill and social capital gradients in selfreported health and explore the interaction between human capital and social capital to examine if and where social capital is a mediator or a moderator of years of schooling and cognitive abilities. We find large education gaps in self-reported health across all countries in our sample and a strong positive relationship between self-reported health and both literacy and trust in the majority of countries. Education and skill gradients in self-reported health appear to be largest in the United States and smallest in Italy, France, Sweden and Finland. On average around 5.5% of both the schooling gap in self-reported health and the literacy gap in self-reported health can be explained by the higher levels of interpersonal trust that better educated/more skilled individuals have, although the mediating role of trust varies considerably across countries. We find no evidence of a moderation effect: the relationships between health and years of schooling and health and cognitive skills are similar among individuals with different levels of trust. Introduction Poor health is a major burden for the affected individual, but also for governments [1]. Recent estimates suggest that health expenditures account for as much as 9% of GDP across OECD countries; in the United States, they represent as much as 16% of GDP [2]. Moreover, there is a large body of evidence highlighting considerable disparities in health across population subgroups, with individuals with low socio-economic backgrounds and poor educational PLOS ONE | DOI:10.1371/journal.pone.0149716 February 22, 2016 1 / 16 Education, Health and Social Capital attainment being disproportionately more likely to be in ill health [3–7]. Tackling the high incidence of poor health and inequalities in health outcomes has risen to the top of policy agendas. In recent years, new emphasis has been put on the social determinants of health [8]. The social context in which individuals live and the social connections they forge have profound effects on their health and well-being [9–18]. Individuals and groups interact with each other in ways that may influence their behaviors and lifestyles, their willingness and ability to take advantage of community resources, such as public services, and to cope with hardship and stress. Social characteristics add to the effects of material circumstances, from housing to transport, from working conditions to the quality of public services and institutions. A large body of evidence both in the economics and public health literature documents a robust positive relationship between education and health (see [19–22] for reviews) and social capital and health [23]. Many definitions of social capital exist. In the context of this paper we borrow Francis Fukuyama’s definition of social capital. Fukuyama conceives social capital as “shared norms or values that promote social cooperation, instantiated in actual social relationships” [24]. With respect to the education-health gradient, challenges involved in assessing causality mean that there is no consensus on what determines observed relationships. Education and health may in fact interact in three not mutually exclusive ways: education may determine health, health may determine education and, finally, education and health may be jointly determined by another factor or set of factors [19, 25–28]. Two separate strands of literature have examined the education-health gradient: the first has attempted to establish the causality and the direction of the association using natural experiments that induced exogenous variations in educational attainment or participation. Empirical studies estimating the effect of education on health suggest that in some contexts exogenous increases in schooling are associated with better health outcomes [14, 29–34], while in others there is no effect [35–39]. The second strand has attempted to describe the mechanisms that may lead to the observed education-health link [3, 4, 40], whether this varies across countries [40–42], cohorts [43] and health indicators [44, 45]. One way in which education can promote health is by increasing labour market participation and the incomes individuals have. However, the education-health link is only partially explained by the increased income that highly educated individuals earn [46, 47]. Education might in fact promote better health through improved cognitive skills, for example by enabling individuals to be more efficient at maintaining good health [27], by prompting them to make better health choices [46, 48], and increasing their willingness and ability to access and use information [22] and by increasing their investment in social capital. Interpersonal trust represents the cognitive dimension of social capital [49] and it has been found to be vital for well-being and economic prosperity [2, 50–54]. A large body of evidence also details a strong positive relationship between levels of interpersonal trust and health ([12, 55] for reviews). In our study we focus on interpersonal trust to examine social capital gradients in self-reported health. Interpersonal trust may (...truncated)