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Little Certainty with Risks (Part 2)
Part 2: Swapping Risks
Also the risks connected to the examinations themselves are often not communicated appropriately: „A colonoscopy is a highly invasive intervention, very uncomfortable and its potential for damage is quite high“, Jørgensen says. According to the Danish scientist people die in very rare cases, for example due to complications arising from an accidental perforation of the intestine. Sometimes bleeding occurs after removing a benign polyp and the sedation during the examination may give rise to complications in elderly people. In Denmark, colonoscopy is not going to be used as a first line screening program because "the evidence on benefits from it is too poor."
Christian Pox confirms that no direct proof from a randomised trial exists for any benefits of this screening. However, the head of department at the Ruhr-University Bochum says that there were many indirect indications. Experts believe that the test for occult blood in the stool decreased the occurrence of colorectal cancer by 30 percent because a positive test result was always followed by a colonoscopy. „If one acts on the assumption that only carcinoma were found with the help of the stool test it should be possible to reduce the cancer rate by 60 to 90 percent with a routine colonoscopy“, the gastroenterologist says, who also is part of the scientific advisory council on preventive colonoscopy.
These theoretical considerations are partly the basis for implementing colonoscopy screening in Germany at the end of 2002. The sceptic Jorgensen, however, points out: „It does not matter which medical intervention we are talking about: It is never sufficient to concentrate solely on the benefits. One always has to consider the risks, too.“ Also Pox points out: „Colonoscopy is a good thing, but it is not perfect.“
No proof for benefits of skin cancer screening
On 1 July 2008, screening for skin cancer was introduced in Germany - the only country in the whole world to do so despite the fact that so far not one controlled randomised study was undertaken to prove a benefit of such a measure. Now any insured over the age of 35 has the right to get their skin examined every two years by a practitioner or dermatologist searching for any suspicious changes. The chairman of the Federal Joint Committee (G-BA), the highest panel in the German public health sector, Rainer Hess recently said in the political magazine Der Spiegel, that the public pressure had been enormous. "Dermatologists had been pointing out the problem for years and the media were willing to stoke fears concerning skin cancer. Against this background, also the willingness of Association of Statutory Health Insurance Physicians increased to support the screening despite small evidence."
Klaus Koch, scientific author of two books that are concerned with the benefits and risks of screenings says: „Fear is being induced in order to ease it again through a screening.“ Data from the US, for example, show that the risk of getting a melanoma is about two percent for men and a little more than one percent for women. The risk to die of it is even smaller than one percent. „Both the threat of contracting a cancer and the benefit of a screening is often overestimated“, Koch says.
Moreover, Koch stresses that the skin cancer screening concentrates on a health problem that is compared to other problems rather small. Indeed, screening for skin cancer may cost public insurances a few hundred million Euros per year since 45 million German citizens are entitled for this examination. A lot of cash for times where money is short. „We should also consider the question how much money is spent on what measure“, Koch says. „The money could ultimately be used for other things.“
The patients' interests, however, are different ones: they want to protect their health and believe that they can decrease their risk of dying of cancer with routine examinations. But Koch raises concerns: „When somebody participates in screening they should be aware of the fact that you may reduce a risk but at the same time enter new risks. You are swapping risks.“ Even though the potential for harm in skin cancer screening is not particularly high, all patients always need to be totally informed about all benefits and most important all risks.
Standards on communication may help here, standards that are to be followed by organisations and doctors. The German Network for Evidence Based Medicine in Berlin - a non-profit organisation for the advancement of public health care in Berlin prepared such criteria last year that should aid in the creation of patient information for examinations in terms of cancer screenings. One of the minimum requirements is: „In order to assess the benefits of a measure, those interested, on one hand, need unbiased information on how high the risk is to contract a specific cancer or to die of it; on the other hand they need information on how high these risks are despite screening.“ Therefore, it may be sensible in the end to decide to participate in a screening program and it may just the same be sensible to decide against it.
- Part 1: Little Certainty with Risks
- Part 2: Swapping Risks