Health Professionals can Sustain Proficiency in Motivational Interviewing With a Moderate Amount of Training: An Intervention Fidelity Study

INTRODUCTION: Motivational interviewing (MI) proficiency may erode quickly, limiting its effectiveness. We examined whether health professionals completing a 2-day workshop, with 3 to 5 hours of personalized coaching, and twice-yearly group reflections sustained proficiency for the duration of a hip fracture rehabilitation trial and whether intervention was implemented as intended. METHODS: A fidelity study was completed as part of a process evaluation of the trial that tested whether physical activity increased among hip fracture patients randomly allocated to receive MI (experimental) compared with dietary advice (control) over ten 30-minute sessions. Twelve health professionals (none were proficient in MI before trial commencement) delivered the intervention for up to 952 days. Two hundred experimental sessions (24% of all sessions, 83 patients) were randomly selected to evaluate proficiency using the MI Treatment Integrity scale; along with 20 control sessions delivered by four dietitians. Linear mixed-effects regression analyses determined whether proficiency was sustained over time. Dose was assessed from all experimental sessions ( n = 840, 98 patients). RESULTS: Intervention was implemented as intended; 82% of patients received at least eight 30-minute sessions. All motivational interviewers were proficient, whereas dietitians did not inadvertently deliver MI. Time had no effect on MI proficiency (est < 0.001/d, P = .913, 95% CI, -0.001 to 0.001). DISCUSSION: MI proficiency was sustained in a large trial over 2.6 years by completing a 2-day workshop, 3 to 5 hours of personalized coaching, and twice-yearly group reflections, even for those without previous experience; further research needs to establish the maximum duration of training effectiveness.