title: The contextual effects of social capital on health: a cross-national instrumental variable analysis.
abstract: Past research on the associations between area-level/contextual social capital and health has produced conflicting evidence. However, interpreting this rapidly growing literature is difficult because estimates using conventional regression are prone to major sources of bias including residual confounding and reverse causation. Instrumental variable (IV) analysis can reduce such bias. Using data on up to 167,344 adults in 64 nations in the European and World Values Surveys and applying IV and ordinary least squares (OLS) regression, we estimated the contextual effects of country-level social trust on individual self-rated health. We further explored whether these associations varied by gender and individual levels of trust. Using OLS regression, we found higher average country-level trust to be associated with better self-rated health in both women and men. Instrumental variable analysis yielded qualitatively similar results, although the estimates were more than double in size in both sexes when country population density and corruption were used as instruments. The estimated health effects of raising the percentage of a country's population that trusts others by 10 percentage points were at least as large as the estimated health effects of an individual developing trust in others. These findings were robust to alternative model specifications and instruments. Conventional regression and to a lesser extent IV analysis suggested that these associations are more salient in women and in women reporting social trust. In a large cross-national study, our findings, including those using instrumental variables, support the presence of beneficial effects of higher country-level trust on self-rated health. Previous findings for contextual social capital using traditional regression may have underestimated the true associations. Given the close linkages between self-rated health and all-cause mortality, the public health gains from raising social capital within and across countries may be large.
authors.affiliation: RAND Corporation, Santa Monica, CA, USA. dkim@rand.org
authors.forename: Daniel
authors.initials: D
authors.lastname: Kim
authors.forename: Christopher F
authors.initials: CF
authors.lastname: Baum
authors.forename: Michael L
authors.initials: ML
authors.lastname: Ganz
authors.forename: S V
authors.initials: SV
authors.lastname: Subramanian
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D019049:Developed Countries; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012931:Social Environment; D012944:Social Support; D055815:Young Adult
references.citation: Soc Sci Med. 2008 Apr;66(8):1719-32
references.pmid: 18280021
references.citation: Int J Epidemiol. 2004 Aug;33(4):682-90; discussion 700-4
references.pmid: 15282222
references.citation: J Epidemiol Community Health. 2007 Jun;61(6):491-8
references.pmid: 17496257
references.citation: Lancet. 2001 Jul 21;358(9277):194-200
references.pmid: 11476836
references.citation: J Urban Health. 2006 Sep;83(5):813-26
references.pmid: 16810567
references.citation: J Epidemiol Community Health. 2004 Jan;58(1):71-7
references.pmid: 14684730
references.citation: Soc Sci Med. 2003 Jun;56(12):2367-77
references.pmid: 12742601
references.citation: J Epidemiol Community Health. 2006 Feb;60(2):116-22
references.pmid: 16415259
references.citation: J Health Soc Behav. 1995;Spec No:80-94
references.pmid: 7560851
references.citation: BMJ. 2009 Dec 22;339:b5043
references.pmid: 20028778
references.citation: J Gen Intern Med. 2006 Mar;21(3):267-75
references.pmid: 16336622
references.citation: Am J Epidemiol. 1976 Aug;104(2):107-23
references.pmid: 782233
references.citation: Am J Public Health. 1997 Sep;87(9):1491-8
references.pmid: 9314802
references.citation: N Engl J Med. 2001 Jul 12;345(2):99-106
references.pmid: 11450679
references.citation: J Health Soc Behav. 1997 Mar;38(1):21-37
references.pmid: 9097506
references.citation: Ann Epidemiol. 2007 Apr;17(4):258-69
references.pmid: 17324589
references.citation: BMJ. 2001 May 19;322(7296):1233-6
references.pmid: 11358781
references.citation: Am J Public Health. 2010 Nov;100(11):2296-303
references.pmid: 20864717
references.citation: Am J Epidemiol. 2010 Aug 1;172(3):288-98
references.pmid: 20610467
references.citation: Soc Sci Med. 2008 Jan;66(1):43-56
references.pmid: 17913321
references.citation: Philos Trans R Soc Lond B Biol Sci. 2004 Sep 29;359(1449):1435-46
references.pmid: 15347534
references.citation: Epidemiology. 2006 May;17(3):260-7
references.pmid: 16617274
references.citation: Soc Sci Med. 2006 Aug;63(4):1045-59
references.pmid: 16644081
references.citation: Int J Epidemiol. 1985 Mar;14(1):32-8
references.pmid: 3872850
references.citation: JAMA. 2009 Jun 10;301(22):2331-9
references.pmid: 19509380
references.citation: Soc Sci Med. 2006 Jan;62(2):292-302
references.pmid: 16024152
references.citation: BMJ. 2009 Nov 10;339:b4471
references.pmid: 19903981