Comparison of Direct and Indirect Measures of E-cigarette Risk Perceptions

Abstract

Objectives Risk perception measures of tobacco products relative to cigarettes are commonly used and important to tobacco research given that they may be associated with and predict tobacco use. However, results may differ based on measures used. This study compares direct and indirect approaches to measuring e-cigarette/cigarette risk perceptions. Methods We compared the responses of 519 current smokers on a nationally representative 2014 survey that gauged perceptions of e-cigarettes’ harm relative to cigarettes in two ways: 1) a single-item direct measure of comparative harm and a two-item indirect measure (which measured perceived levels of harm from e-cigarettes and cigarettes independently in two parallel questions). Results We found that 60% of smokers rated e-cigarettes “less harmful” than cigarettes when using a direct comparative risk measure versus 73% when using an indirect measure. Agreement between measure types was fair (Cohen’s Kappa=0.45) and was lower for males, Blacks, older and less educated smokers. Conclusions E-cigarettes were more likely to be rated by smokers as less harmful than cigarettes when using indirect versus direct measures. Additional methodology research into this area is warranted given the importance of risk perceptions to tobacco control interventions, communications, policy-making and regulation.

Practise Patterns and Perceptions of Chest Health Care Providers on Electronic Cigarette Use: An In-Depth Discussion and Report of Survey Results

“…(Brose, Brown, Hitchman, & McNeill, 2015; Eastwood et al, 2015; Mark, Farquhar, Chisolm, Coleman-Cowger, & Terplan, 2015; Martinez-Sanchez et al, 2015; Wackowski, Bover Manderski, & Delnevo, 2016) We note the discrepancy in the perception of ECs between the majority of survey respondents and the RCP position, which generally looked more favorably upon ECs for their potential role for tobacco harm reduction.…”

Criterion validity of measures of perceived relative harm of e-cigarettes and smokeless tobacco compared to cigarettes

“…This study used a two-level coding of perceived harm (“Less harmful” vs. any other option) (27, 41) rather than a 3-level coding (“Less harmful”/“Equally harmful”/“More harmful”) (16, 17, 20, 21). This prevented us from distinguishing participants who rated products as equally vs. more harmful than cigarettes.…”

“…This was done to create direct and indirect measures that had the same levels, as not all measures had “More harmful” and “Don't know” options; also, there were small samples ( n <40) of those rating e-cigarettes and SLT as more harmful than cigarettes on the indirect measures. Even in studies using alternate coding schemes, interpretation of findings has focused on individuals rating e-cigarettes and SLT as less harmful than cigarettes (8, 16, 17, 21, 30). …”

“…Two types of measures include direct measures (e.g., where people rate the harm of using e-cigarettes as lower or higher than the harm of using cigarettes in a single question) and indirect measures (e.g., where people rate the harms of using e-cigarettes and cigarettes on two separate questions, and then ratings are compared to determine whether the harm for one product was rated lower than the other). Studies indicate that cigarette smokers are more likely to rate e-cigarettes and SLT as less harmful than cigarettes on indirect rather than direct measures (20, 21). In one study, nearly 52% of smokers rated snus – a type of SLT – as less harmful than cigarettes on an indirect measure compared to only 22% on a direct measure (20).…”

“…Researchers have hypothesized that direct measures may bias people toward giving a “socially appropriate answer” (i.e., that non-combustible products are just as harmful as cigarettes) (20, 21), thus underestimating the extent to which people believe non-combustible products are less harmful than cigarettes. However, no studies have tested this hypothesis to examine whether one type of measure more accurately reflects public perceptions than the other, or whether each type may reflect a unique aspect of harm perception.…”