Occupation recorded on certificates of death compared with self-report: the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND Death certificates are a potential source of sociodemographic data for decedents in epidemiologic research. However, because this information is provided by the next-of-kin or other proxies, there are concerns about validity. Our objective was to assess the agreement of job titles and occupational categories derived from death certificates with that self-reported in mid and later life. METHODS Occupation was abstracted from 431 death certificates from North Carolina Atherosclerosis Risk in Communities Study participants who died between 1987 and 2001. Occupations were coded according to 1980 Bureau of Census job titles and then grouped into six 1980 census occupational categories. This information was compared with the self-reported occupation at midlife as reported at the baseline examination (1987-89). We calculated percent agreement using standard methods. Chance-adjusted agreement was assessed by kappa coefficients, with 95% confidence intervals. RESULTS Agreement between death certificate and self-reported job titles was poor (32%), while 67% of occupational categories matched the two sources. Kappa coefficients ranged from 0.53 for technical/sales/administrative jobs to 0.68 for homemakers. Agreement was lower, albeit nonsignificant, for women (kappa = 0.54, 95% Confidence Interval, CI = 0.44-0.63) than men (kappa = 0.62, 95% CI = 0.54-0.69) and for African-Americans (kappa = 0.47, 95% CI = 0.34-0.61) than whites (kappa = 0.63, 95% CI = 0.57-0.69) but varied only slightly by educational attainment. CONCLUSION While agreement between self- and death certificate reported job titles was poor, agreement between occupational categories was good. This suggests that while death certificates may not be a suitable source of occupational data where classification into specific job titles is essential, in the absence of other data, it is a reasonable source for constructing measures such as occupational SES that are based on grouped occupational data.