Relative Efficacy of Smoking Cessation Methods

There was an ad in my local paper, on 31st December 2004, for a hypnotherapy practice charging smokers £180.00 to stop. Part of the advertisement read, “The publication ‘New Scientist’ reported research on over 70,000 people, showing hypnosis to be the most effective way to give up the smoking habit.”  

That New Scientist article gets quoted a lot by hypnotherapists, for obvious reasons, but I wonder how many have ever looked at the research behind it?  

The research was, in fact, a review (or ‘meta-analysis’) of existing research into the effectiveness of smoking cessation methods, carried out by Chockalingam Viswesvaran and Frank L Schmidt of the Department of Management and Organizations at the University of Iowa, and was published in the Journal of Applied Psychology in 1992.  This is what it really says.

The review covered 633 studies of smoking cessation methods, involving 71,806 subjects. These studies were sorted into 15 types of program, one of which was hypnosis. 48 of the 633 studies qualified as hypnosis, and they involved 6,020 people. Once adjusted for the 6% of hypnotees who would have given up anyway (established by 41 control groups scattered throughout the review) hypnosis proved to be 30% successful. So out of the 6,020 hypnotees, 1,806 quit thanks to hypnosis. That means that 70,000 of the advertisements’ “over 70,000,” did not stop smoking due to hypnosis. On the other hand, if they had all had hypnosis, another 19,736 would have stopped, instead of the 13,157 who actually did.  

You can have fun analyzing the table below any way you chose. These, I think, are the important points.  

 

Type of Program No. of Studies Total Sample Mean Quit Rate Control Adjustment Net Effectiveness Relative Effectiveness Success Ranking
Cardiac patients 34 4,553 42% 6% 36% 0.83 1
Hypnosis 48 6,020 36% 6% 30% 1.00 2
Miscellaneous 10 1,400 35% 6% 29% 1.03 3
Pulmonary patients 17 1,661 34% 6% 28% 1.07 4
Smoke aversion 103 2,557 31% 6% 25% 1.20 5
Group withdrawal clinics 46 11,580 30% 6% 24% 1.25 6
Acupuncture 19 2,992 30% 6% 24% 1.25 7
Other aversive techniques 178 3,926 27% 6% 21% 1.43 8
Five-day plans 25 7,828 26% 6% 20% 1.50 9
Educational 27 3,352 24% 6% 18% 1.67 10
Medication 29 6,810 18% 6% 12% 2.50 11
Enhanced physician advice 16 3,486 18% 6% 12% 2.50 12
Nicotine gum 40 4,866 16% 6% 10% 3.00 13
Self-care 24 3,585 15% 6% 9% 3.33 14
Physician advice 17 7,190 7% 6% 1% 30.00 15
Totals 633 71,806          
Averages     26%   20%    

(Adapted from "A Meta-Analytic Comparison of the Effectiveness of Smoking Cessation Methods,"

Viswesvaran and Schmidt, Journal of Applied Psychology, 1992, Vol 77, No. 4 534-561.)

Open Mindsci Clinic Hypnotherapy Old Malden Surrey