Reported measures of environmental tobacco smoke exposure: trials and tribulations

OBJECTIVE This report extends previous summaries of reported environmental tobacco smoke (ETS) exposure measures, reviews the empirical evidence of their validity for children's exposure, and discusses future research. DATA SOURCES Studies were identified by computer search and from the authors' research. STUDY SELECTION Studies were selected for inclusion of nicotine and/or cotinine and quantitativereported measures of ETS exposure. DATA SYNTHESIS Five studies found significant associations between reported quantitative exposure of children to ETS and either environmental nicotine or urine cotinine assays. Correlation coefficients between parent reports and nicotine ranged from 0.22 to 0.75. Coefficients for cotinine ranged from 0.28 to 0.71. Correlations increased over time and were stronger for parents' reports of their own smoking as a source of children's exposure than for reports of exposure from others. CONCLUSIONS Empirical studies show general concordance of reported and either environmental or biological measures of ETS exposure. Relationships were moderate, and suggest sufficient validity to be employed in research and service programs. Future studies need to identify the differences in types of reported or objective measures, population characteristics, etc, contributing to observed variability in order to understand better the conditions under which more valid reported ETS exposure and other measures can be obtained. Reported and either environmental or biological measures should be used in combination, and existing measures should be directed to interventions that may reduce ETS exposure among children.