One item susceptibility measure predicts waterpipe and little cigar/cigarillo uptake in a national sample of adolescents and young adults in the United States

INTRODUCTION Adolescents and young adults in the United States (US) are increasingly using non-cigarette tobacco products such as waterpipe (WP) and little cigars/cigarillos (LCC). One way to predict which non-user adolescents and young adults are most likely to use these products is through measuring their susceptibility or openness to using the products. METHODS We conducted a national phone survey (baseline) and an internet survey (follow-up) of adolescents and young adults (ages 13-25 years), who, at baseline, had never used WP (N=1002) or LCC (N=990). At baseline, we measured susceptibility using a single item, asking participants whether they would try WP or LCC if their best friend offered it to them, and subsequently measured uptake at follow-up. We conducted multivariate regression analyses to determine whether product-specific susceptibility was a significant predictor of uptake at follow-up. RESULTS Participants who were susceptible and participants who had ever used another tobacco product had higher odds of using WP (AOR=3.5, AOR=4.2) and LCC (AOR=3.2, AOR=5.3) at follow-up than those who were not susceptible to those products, and had not ever used tobacco products respectively, controlling for sociodemographic factors. The one-item measure had adequate sensitivity (WP=51.4%, LCC=40.2%) and specificity (WP=84.9%, LCC=87.9%). CONCLUSIONS Our national study of US adolescents and young adults shows that a one-item susceptibility measure at baseline was a significant predictor of WP and LCC uptake at follow-up, even after controlling for other predictors. Future research should assess the predictive validity of the one-item compared to the multi-item scale.