Secondhand Smoke Exposure and Validity of Self-Report in Low-Income Women and Children in India.

Abstract

There is limited validation of self-reported measures for secondhand smoke (SHS) exposure in low- and middle-income countries. We evaluated the validity of standard self-reported measures among women and children in urban India. Structured questionnaires were administered, and household air and hair samples were analyzed for nicotine concentration. In total, 141 households of 70 child and 71 adult participants were included. Air nicotine was detected in 72 (51%) homes, and 35 (75%) child and 12 (56%) adult participants had detectable hair nicotine. Correlation between air and hair nicotine was significant in children (<i>r</i> = 0.5; <i>P</i> = .0002) but not in adults (<i>r</i> = -0.1; <i>P</i> = .57). Poor correlation was found between self-reported measures of exposure and both air and hair nicotine. No questions were significantly correlated with hair nicotine, and the highest-magnitude correlation with air nicotine was for how often someone smoked inside for adults (<i>r</i> = 0.4; <i>P</i> = .10) and for home preparation of mishri (a smokeless tobacco product prepared for consumption by roasting) for children (<i>r</i> = 0.4; <i>P</i> = .39). The highest value for sensitivity by using air nicotine as the gold standard was for whether people smelled other families preparing mishri (47%; 95% confidence interval: 31-62) and prepared mishri in their own homes (50%; 95% confidence interval: 19-81). These results raise caution in using or evaluating self-reported SHS exposure in these communities. More appropriate questions for this population are needed, including mishri preparation as a source of SHS exposure.