PURPOSE: In case-control studies, the issue of whether living or deceased controls should be used for deceased cases has been controversial. METHODS: Using data from a study of @entity5 among @entity1 that selected both live (n = 1910) and deceased controls (n = 596) for cases of @entity96 (109 deceased, 59 living), we examined the effects of using information from proxy respondents (cases and controls) and from live cases and controls on associations between @entity96 and known risk factors. Cases diagnosed between 1984 and 1988 were selected from eight population-based @entity5 registries. Live controls were recruited by random digit dialing, deceased controls from death certificate files. Controls were matched to cases on geographic area, year-of-birth, and race. RESULTS: Adjusted odds ratios (OR) calculated for deceased cases and controls, when compared to odds ratios for live cases and controls, were attenuated towards the null value for history of @entity99 (4.7 vs. 14.9), blood transfusions (1.1 vs. 7.8), and @entity82 (9.3 vs. 51.1). When all cases and living controls were used, odds ratios did not differ substantially from those for living cases and controls except for @entity82 (OR = 154.2). For smoking, the odds ratios were similar in all analyses. Adjustment for type of interview (self, proxy) did not eliminate differences between results for living and deceased subjects; significant interactions were found between type of interview and @entity99 , @entity82 , and blood transfusions. CONCLUSIONS: Selection of live controls for deceased cases is recommended to decrease misclassification in measures of exposure.

An empirical study of the use of living versus deceased study subjects: associations with @entity96 in the selected XXXX study.

@entity1 :: ('9606', 'Species') :: ['men'] @entity82 :: ('MESH:D005355', 'Disease') :: ['cirrhosis'] @entity96 :: ('MESH:D008113', 'Disease') :: ['liver cancer'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity99 :: ('MESH:D056486', 'Disease') :: ['hepatitis']
@entity5 :: (MESH:D009369,Disease) :: ['cancers']
