Drug users and non-drug users endorse telling the truth to researchers

Background: The literature has shown that the self-report of drug users is reliable and valid. However, drug users are still commonly seen as liars. It was hypothesized that drug users and non-drug users would not differ in their reported likelihood to lie to a researcher.

Methods: Participants in the NIDA funded study, Transformative Approach to Reduce Research Disparities Towards Drug Users, were asked questions on how likely they were to lie to a researcher about 11 kinds of sensitive research information. Answers were reported on a scale ranging from 1 (not at all likely) to 5 (very likely). A composite lying score was constructed and the scores of drug users (n=329) and non-drug users (n=285) were compared.

Results: The Wilcoxon-Mann-Whitney test indicated a significant difference in average lying scores between drug users and non-drug users (median= 1 for both groups; p=0.0023). However, two questions included in the composite score assessed likelihood to lie about drug use (frequency of use and type of drug). Because non-drug users have no reason to lie about using drugs, the two questions were removed from analysis. The second Wilcoxon-Mann-Whitney test indicated no difference in scores between drug users and non-drug users (p=0.1570).

Discussion: Results show that there is no difference between groups in their reported likelihood to lie to a researcher. Drug users can be asked to self-report sensitive information.