Volumetric choice experiment to estimate the impact of e-cigarette and heated tobacco product characteristics on substitution and complementary use among adults who smoke cigarettes and recently initiated e-cigarette use.

backgroundThis study addresses the limited evidence of the impact of product characteristics on demand for and the substitutability of electronic cigarettes (e-cigarettes) or heated tobacco products for combusted cigarettes among people who smoke and have newly begun to use e-cigarettes.

methodsA sample of 318 adults who smoke and recently initiated/reinitiated e-cigarette use participated in an online volumetric choice experiment in 2020-2021 to assess stated preferences for consumption and own and cross-price elasticities of three e-cigarette options (cig-a-like, vape pen or tank, closed pod system), heated tobacco product (IQOS) and their usual brand of cigarettes. Product attributes manipulated were price, flavour, level of harm, how well the product reduces cravings to smoke, and how discretely the product can be used. Multilevel zero-inflated negative binomial models were used to model the purchased quantities.

resultsCigarettes were preferred over all alternatives. However, demand for cig-a-likes, but not IQOS, increased when cigarette prices were higher. Higher prices for e-cigarettes and IQOS did not increase demand for cigarettes. The odds of buying e-cigarettes/IQOS were higher when their harm was stated as low or unknown versus being similar to cigarettes (ie, very high). Other attributes (including various flavour options) were not significantly associated with demand for e-cigarettes or IQOS.

conclusionsPeople who smoke and recently began using e-cigarettes might substitute cig-a-likes for cigarettes when cigarette prices are higher. Policies to increase the cost of combusted cigarettes as well as communicate lower relative harm and low absolute harm of e-cigarettes may facilitate switching behaviour.