Conclusions
ABUSE
In our study, participants receiving a US $30 gift code upon completion of the survey were more likely to complete the survey than those receiving a US $15 gift code both before and after completing the survey; participant demographics in the final sample for these 2 approaches did not differ significantly. Future web-based surveys, particularly those examining US adults who use e-cigarettes, could consider providing the full incentive upon survey completion. Future research should continue to examine approaches for increasing follow-up rates in web-based longitudinal surveys and consider how these approaches may affect response rates across varying populations.Research reported in this publication was supported by the National Institute on Drug Abuse (NIDA) and Food and Drug Administration (FDA) Center for Tobacco Products (CTP) under Award Number U54DA036105. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health (NIH) or the FDA.Conflicts of Interest: None declared.