Influencer Marketing: a Survey-based Experiment Among Adolescents

Harm perceptions of e-cigarettes

Responses to two questions adapted from PATH, "Based on the videos you just watched, do you think using e-cigarettes for vaping nicotine is harmful to your health?" "Based on the videos you just watched, do you think people harm themselves when they use e-cigarettes for vaping nicotine?" Outcome was assessed on the 0 (Not harmful at all) - 100 (Very harmful) scale. Since the items were closely related (α=0.87), they were combined (by summing all the non-missing values of the items) into one variable.

Time frame: one-time assessment after the experimental exposure (immediately post-treatment)

Perceived appeal of e-cigarettes

Responses to the following questions: using e-cigarette is: * not cool/cool, * unattractive/attractive, * boring/fun were assessed on the 7-point semantic differential scale with the word pairs anchored at each end. The scale was adapted from prior research. The items were combined (by summing all the non-missing values of the items) into one variable (α=0.93).

Time frame: one-time assessment after the experimental exposure (immediately post-treatment)

Susceptibility to use e-cigarettes

Susceptibility to use e-cigarettes was measured (among never-users of e-cigarettes), using the validated three-item scale adapted from PATH, and combined into one variable (α=0.93). Consistent with prior research, the measure was dichotomized with responses "definitely not" to all items being coded as "not susceptible" and responses "probably not," "probably yes", or "definitely yes" being coded as "susceptible."

Time frame: one-time assessment after the experimental exposure (immediately post-treatment)

Perceptions of influencer credibility

Perceptions of influencer credibility (i.e., honesty, trustworthiness, knowledge) were assessed using a 0 (e.g., dishonest) -100 (e.g., honest) scale that has been validated in prior research.

Time frame: assessed 10 times immediately after each video