Associations Between Self‐Reported and Biological Measures of Nicotine Consumption Among Young Adult Nondaily Cigarette Smokers

Background and Objectives Intermittent, dual use of cigarettes and e‐cigarettes is a common pattern among youth and young adults. However, little is known about the validity of self‐report measures of nicotine consumption in these populations. The goal of the present study was to examine associations between self‐reported frequency of cigarette and e‐cigarette use and nicotine levels in hair samples at two assessments 1 year apart. Methods...