The Impact of Computer-Mediated versus Face-to-Face Motivational-Type Interviews on Participant’s Language and Subsequent Behavior Change: Randomized Study (Preprint)

BACKGROUND Motivational Interviewing (MI) is frequently used to facilitate behavior change. The use of change talk during motivational interviews can predict subsequent behavior change. Yet, no studies have compared the information obtained from traditional face-to-face motivational interviews and computer-mediated motivational interviews or result in the same amount of behavior change. OBJECTIVE This study investigated if face-to-face motivational-type interviews and computer-mediated motivational-type interviews (MTIs) elicit the same amount of change talk and behavior change when young adults discuss their ambivalence about using marijuana. METHODS One hundred and fifty frequent marijuana users, occasional marijuana users, and non-marijuana users participated in the study; all participants reported being at least moderately ambivalent about their current level of marijuana use. Participants were randomly assigned to complete a brief motivational-type interview using either the standard face-to-face format or a computer-mediated format. Amrhein’s manual for assessing the presence of ‘change talk’ and ‘sustain talk’ was used to code the language produced by respondents in each interview format. Reduction in marijuana use was assessed at a two-month follow-up. RESULTS Word count was significantly higher in face-to-face MTIs than computer-mediated MTIs. Face-to-face MTIs also elicited significantly more reasons for reducing future marijuana use (i.e., change talk) even after controlling for verbosity. The strength of an interviewee’s statements denoting a commitment to reduce their marijuana use (i.e., change talk) and their subsequent frequency of marijuana use at two-month follow-up were negatively correlated, r=-.41, P<.001. The association between Time 1 change talk and Time 2 marijuana use depended upon the type of motivational interview that participants experienced: face-to-face MTI versus computer-mediated MTI. A negative binomial regression with a log link function was used to probe this relationship after controlling for two covariates: gender and Time 1 marijuana use. Among participants in the face-to-face MTI condition, Time 2 marijuana use decreased as the strength of Time 1 change-talk increased, although this finding was not significant (B=-.21, P=.08). Among participants in the computer-mediated MTI condition, however, Time 2 marijuana use was not significantly related to the strength of Time 1 change talk (B=.19, P=.16). CONCLUSIONS The implications of these findings for conducting computer-mediated motivational interviews are discussed.