How does physician advice influence patient behavior?: Evidence for a priming effect

Objective: To explore a potential "priming effect" of physician advice on patient responses to behavioral change interventions. Design: Randomized controlled trial with a 3-month follow-up. Setting: Four community-based group family medicine clinics in southeastern Missouri. Participants: Adult patients (N = 915). Interventions: Printed educational materials designed to encourage patients to quit smoking, eat less fat, and increase physical activity. Main Outcome Measures: Recall, rating, and use of the educational materials; changes in smoking behavior, dietary fat consumption, and physical activity. Results: Patients who received physician advice to quit smoking, eat less fat, or gee more exercise prior to receiving intervention materials on the same topic were more likely to remember the materials, show them to others, and perceive the materials as applying to them specifically. They were also more likely to report trying to quit smoking (odds ratio [OR] = 1.54, 95% confidence interval [CI] = 0.95-2.40), quitting for at least 24 hours (OR = 1.85, 95% CI = 1.02-3.34), and malting some changes in diet (OR = 1.35, 95% CI = 1.00-1.84) and physical activity (OR = 1.51, 95% CI = 0.95-2.40). Conclusions: Findings support an integrated model of disease prevention in which physician advice is a catalyst for change and is supported by a coordinated system of information and activities that can provide the depth of detail and individualization necessary for sustained behavioral change.