Measuring environmental tobacco smoke exposure in infants and young children through urine cotinine and memory-based parental reports: empirical findings and discussion

Objective-This study examined the reliability and potential biases of two m ine collection methods from which cotinine measures were obtained and the v alidity of memory-based parental reports of their children's exposure to en vironmental tobacco smoke (ETS). Design-Structured interviews were conducted with mothers of infants and you ng children to obtain memory-based estimates of recent ETS exposure. Urine samples were collected through standard and cotton roll collection methods for cotinine analysis. Setting-All interviews took place at an off-campus research facility. Urine samples were collected at the study office or the subjects' homes. Participants-Mothers were recruited from San Diego county sites of the Wome n, Infants, and Children (WIC) Supplemental Food and Nutrition Program. Sam ple 1 (infants) consisted of eight boys and eight girls aged 1-44 months (m ean = 12.6 months). Sample 2 (children) included 10 boys and 10 girls aged 3-8 years (mean = 61.2 months). Main outcome measures-Urine cotinine and memory-based parent reports of ETS exposure from structured interviews. Results-There was overall high reliability for urine cotinine measures and no effect of collection method on urine cotinine levels. Memory-based repor ts obtained from smoking mothers showed moderately strong and consistent li near relationships with urine cotinine measures of their infants and childr en (r = 0.50 to r = 0.63), but not for reports obtained from non-smoking mo thers. Conclusions-Memory-based parental reports of short-term ETS exposure can pl ay an important role in quantifying ETS exposure in infants and children.