SMOKERS AND NONSMOKERS ESTIMATES OF THEIR PERSONAL RISK OF CANCER ANDOF THE INCREMENTAL RISK ATTRIBUTABLE TO CIGARETTE-SMOKING

Estimates were obtained from 420 members of the public, 117 of whom we re smokers, of the risk of an hypothetical target person, described as a 35-year-old man with no previous illness, contracting cancer as a c onsequence of exposure to combinations of different risk factors. The presence/absence of three risk factors-cigarette smoking, occupational radioactive exposure, and radon gas in the home-was used to generate eight target descriptions. Ratings were on an open-ended ratio scale w here 0 represented no risk and 100 an average level of risk for men of the same age. In addition, subjects rated their own risk of contracti ng cancer. Results showed that, compared with non-smokers, smokers gav e higher estimates of their own risk, but lower ratings of the increme ntal risk attributable to cigarette smoking by the target. Smokers and non-smokers did not differ in the incremental risk they attributed to occupation or radon. The findings are used to question the view that smokers 'already know' that they are damaging their health and that th eir attitudes hence have little relevance to their behaviour.