“Don't end up saying 'if only.' Get tested,” says the US journalist Katie Couric of screening for colon cancer. However, as it is a complex and emotional issue, the promotion of cancer screening is controversial. The recent trend for celebrities to endorse personally relevant cancer-screening programmes has therefore come under scrutiny. Is it, in fact, a good thing, and does it actually have any impact?

To try and come up with some answers, Robin J. Larson and colleagues have analysed data taken from a random-digit-dialling survey conducted in the United States during 2001–2002. Their results constitute the first data from a nationally representative sample of Americans of screening age who were asked about their exposure to, and the influence of, celebrity endorsements of cancer screening.

They report that, of those approached, 72% of people known to be eligible — that is, people of screening age and without a history of cancer — and 51% of people thought to be potentially eligible responded to the survey. This involved 360 women of 40 years or older and 140 men of 50 years or older. When asked if they 'had seen or heard a celebrity talk about' various screening programmes, most people responded positively: 73% of women for mammography, 63% of men for prostate-specific-antigen (PSA) testing, and 52% of adults for sigmoidoscopy or colonoscopy. In addition, of those people who had heard celebrity endorsements, the percentage who said they were more likely to undergo screening was 25% for mammography, 31% for PSA testing and 37% for sigmoidoscopy or colonoscopy.

The authors acknowledge that there are limitations to this study. For example, the study parameters mean that there are no data on whether celebrity endorsements encourage screening use in individuals for whom it would not be recommended. Furthermore, the authors are unable to ascertain whether the results were affected by the desire of respondents to give their perceived 'right answer' to the study questions.

On a personal level, undergoing cancer screening can have far-reaching consequences and should not be undertaken lightly. Partaking in informed and thoughtful discussions before making the decision to be screened is therefore increasingly being encouraged by organizations such as the US Preventative Services Task Force. The authors recommend that the provision of information, rather than persuasion, is the most appropriate approach to cancer screening, and they think that the persuasively emotive and one-sided pleas of celebrities to “Get tested” do not sit well with this view.