RT Journal Article SR Electronic T1 Correlates of tobacco product initiation among youth and adults in the USA: findings from the PATH Study Waves 1–3 (2013–2016) JF Tobacco Control JO Tob Control FD BMJ Publishing Group Ltd SP s191 OP s202 DO 10.1136/tobaccocontrol-2020-055671 VO 29 IS Suppl 3 A1 Kasza, Karin A A1 Edwards, Kathryn C A1 Tang, Zhiqun A1 Stanton, Cassandra A A1 Sharma, Eva A1 Halenar, Michael J A1 Taylor, Kristie A A1 Donaldson, Elisabeth A1 Hull, Lynn C A1 Day, Hannah A1 Bansal-Travers, Maansi A1 Limpert, Jean A1 Zandberg, Izabella A1 Gardner, Lisa D A1 Hammad, Hoda T A1 Borek, Nicolette A1 Kimmel, Heather L A1 Compton, Wilson M A1 Hyland, Andrew YR 2020 UL http://tobaccocontrol.bmj.com/content/29/Suppl_3/s191.abstract AB Objective To report on demographic and tobacco product use correlates of tobacco product initiation (cigarettes, electronic nicotine delivery systems (ENDS), cigars, hookah and smokeless tobacco) among the US population.Design Data were from the first three waves (2013–2016) of the Population Assessment of Tobacco and Health Study, a nationally representative, longitudinal cohort study of US youth (aged 12–17 years) and adults (aged 18+ years). Never users of at least one type of tobacco product at Wave 1 (W1, 2013/14) or Wave 2 (W2, 2014/15) were included (n=12 987 youth; n=25 116 adults). Generalised estimating equations were used to evaluate the association between demographic and tobacco product use characteristics at baseline, and tobacco product initiation at follow-up (ever, past 30 day (P30D), frequent (use on 20 or more of thepast 30 days)) over two 1-year periods (W1–W2 and W2–Wave 3).Results Youth aged 15–17 years were more likely than youth aged 12–14 years and adults aged 18–24 years were more likely than older adults to initiate P30D tobacco use across products; non-heterosexuals were more likely than heterosexuals to initiate P30D cigarette and ENDS use. Older adults were more likely than young adults, and males were more likely than females, to be frequent users of ENDS on initiation. Ever use of another tobacco product predicted P30D initiation of each tobacco product.Discussion Other tobacco product use and age predict P30D tobacco initiation across products whereas associations with other demographic characteristics vary by product. Continued contemporary evaluation of initiation rates within the changing tobacco product marketplace is important.