The effect of physician's 30 s smoking cessation intervention for male medical outpatients: a pilot randomized controlled trial.

Objective: To study the effectiveness of a very brief advice (<30 s) on smoking cessation.

Design: A 'proof-of-principle' single-blind, randomized controlled trial (RCT).

Setting: Medical outpatient clinics of a general hospital in Guangzhou, China.

Participants: One hundred and twenty-six male current smokers randomly allocated into an intervention (n = 74) and a control group (n = 52). Intervention A health warning by physicians that half of all smokers would be killed by smoking, an advice to quit immediately and referral to a cessation clinic. The control group received none.

Outcomes: Primary: seven-day quitting point prevalence at 6 months. Secondary: 7-day point prevalence at 1, 3 and 12 months, sustained abstinence at 3, 6 and 12 months, smoking reduction by half and cessation clinic attendance.

Results: By intention-to-treat analysis, 7-day quitting point prevalence rates at four follow-ups were 27.0, 23.0, 21.6 and 18.9% in the intervention group, compared with 5.8, 3.8, 5.8 and 5.8% in the control group (first three P < 0.05). At 3, 6 and 12 months, sustained abstinence prevalence rates were 18.9, 17.6 and 14.9% versus 3.8, 3.8 and 3.8% (P = 0.035, 0.046, 0.074). More smokers in the intervention group had reduced smoking. Almost no participants attended the cessation clinic.

Conclusion: Our findings support the need for large RCTs on minimal interventions with the 'one in two' warning.