Research shows that for every 33 conversations health professionals have with patients about their smoking, one will result in a patient successfully quitting.
A systematic review conducted through the Cochrane Collaboration in 2008 highlights that brief advice from a health professional can double the rate of quitting. Stead, Bergson and Lancaster pooled data from 17 trials of brief advice versus no advice. They detected a significant increase in the rate of quitting smoking among those who received brief advice compared with those who received no advice (relative risk 1.66 and 95% confidence interval 1.42 to 1.94).
Stead L., Bergson G., Lancaster T. Physician advice for smoking cessation. Cochrane Database Syst Rev 2008; (2): CD000165