Smoking status by proxy and self report: rate of agreement in different ethnic groups

Objective-To examine the rate of agreement between proxy and self report of smoking status in Hispanics compared with other ethnic groups. Design-Data source is the 1990 California Tobacco Survey (CTS) which includes proxy and self reported smoking status. The CTS is a random digit dialled survey conducted in 57 244 households. A sample of 10 011 adults was included in the analyses. Main outcome measure e-Percentages of agreement and disagreement between self report and report by other member of the household on smoking status. Results-Cohen's kappa coefficients of agreement on smoking status between self report and proxy report was highest in non-Hispanic whites and African Americans (K = 0.91), followed by Asian Americans (kappa = 0.82) and Hispanics (K 0.76). Among adults identified as current smokers by proxy, a lower percentage of Hispanics compared with non-Hispanics indicated that they were current smokers (odds ratio (OR) = 3.74, 95% confidence intervals (CI) = 3.28 to 4.20). Furthermore, agreement between proxy and self report was also lower in Hispanics of low acculturation compared with Hispanics with a high level of acculturation (OR 0.40, 95% CI = 0 to 0.94). Conclusions-The agreement between self reported and proxy reported smoking status is higher among non-Hispanics compared with Hispanics. Smoking rates in different ethnic groups that are estimated by telephone surveys including proxy and self report might not be comparable.