Results
Of the 902 participants invited to the follow-up in each group, a higher proportion of those in the conditional (662/902, 73.4%) than the hybrid group (565/902, 62.6%) started the survey (Number and percentage of participants completing each stage of a web-based survey by incentive structure in wave 4 of the Vaping and Patterns of e-Cigarette Use Research Study, a longitudinal survey of US adults who frequently use e-cigarettes (July to September 2022).Characteristics of participants deemed valid upon completion of the wave 4 follow-up survey of the Vaping and Patterns of e-Cigarette Use Research Study, a longitudinal web-based survey of US adults who frequently use e-cigarettes from July to September 2022, by incentive structure group.