Translation by Cancer Rose, nov 5, 2021
Bad statistic of the month October: Breast cancer month October - Pink ribbons instead of information
Bad Statistic of the Month
Berlin psychologist Gerd Gigerenzer, economist Thomas Bauer from Bochum, and statistician Walter Krämer from Dortmund began publishing the “Bad Statistic of the Month” (“Unstatistik des Monats”) in 2012. Katharina Schüller, managing director and founder of STAT-UP, joined the team in August 2018. Every month they question recently published statistics and their interpretations. Their underlying aim is to help the public deal with data and facts more rationally, interpret numerical representations of reality correctly, and describe an increasingly complex world more adequately. Further information on this initiative can be found at www.unstatistik.de and on the Twitter account @unstatistik.
October is Breast Cancer Awareness Month. You would think that women would be particularly well informed during this month. To do this, we typed "Breast Cancer Month October 2021" into Google and looked at the entries on the first page. All of them promote early detection, but none of them report what the scientific studies have found about its benefits and harms. Before we look at the entries, it's good to take a look at the results of scientific studies involving more than 500,000 women so far.
They show: When 1,000 women age 50 and older go for screening, 4 of the women die of breast cancer within about 11 years, and for women who don't go for screening, 5. So one fewer woman dies of breast cancer for every 1,000.
However, the total number of women dying from any cancer (including breast cancer) does not change; 22 in both groups. That is, one fewer woman in the screening group dies with a diagnosis of breast cancer, but one more woman dies of another cancer. So, overall, there is no evidence that screening saves or prolongs lives.
But women who go for screening face two harms. One in 100 out of 1,000 receive unnecessary biopsies due to false alarms, and 5 women have part or all of their breast removed unnecessarily. This information should be delivered in October, Breast Cancer Awareness Month, so that women can make an informed decision for or against early detection (see also the "Fact Box on Early Breast Cancer Detection through Mammography Screening" „Faktenbox zur Brustkrebs-Früherkennung durch Mammographie-Screening“
by the Harding Center for Risk Literacy, led by "statistician" Prof. Dr. Gerd Gigerenzer).
Google hit pages provide almost no information about the benefits and harms of screening
So what do the Google search results or web pages tell us? Euronews.com gives no information at all about the benefits and harms of screening. Instead, the website promotes pink ribbons and a pink duck parade. The womens.es website, on the other hand, gives a figure: Early detection "reduces the likelihood of death by 25 percent." Does that mean that for every 100 women, 25 fewer will die of breast cancer? No. This figure is found by reporting the reduction from 5 to 4 in 1,000 women as "20 percent less" and rounding it up to 25 percent. Here, I suspect readers are unaware of the difference between a relative risk (25 percent less) and an absolute risk (1 in 1,000). Indeed, studies show that many women (and men) do not see through this trick.
On their website, the Cancer League of Eastern Switzerland Krebsliga Ostschweiz encourages mammography screening, giving many figures (like the number of women and men who have breast cancer) but none about benefits and harms. The Ministry of Social Affairs, Health, Integration, and Consumer Protection in Brandenburg Webseite again advises early detection on its website. It reports many figures, such as the average age at which women are diagnosed, but none that allows an informed decision - quite different from that in the fact box. Among other things, the company health insurer HMR advises self-testing of the breast by palpation, without mentioning that studies show that this does not reduce breast cancer mortality but can raise false alarms and unnecessary fears. The website also recommends mammography, again without information about benefits and harms.
Early detection is also mislabeled as "prevention," - which is widespread and one of the reasons why many people think that mammography prevents cancer. Vaccination is prevention and prevents diseases; early detection, on the other hand, means that an already existing disease is detected. On the rest of the web pages, it went on like this - entirely without information about benefits and harms, but with celebrities, pink ribbons, teddy bears, and flamingos.
Since different users get different results on the first page of a Google search, you should try it yourself. However, most of us find reliable information only on the later pages, and about 90 percent of all clicks reach the first page only.
In 2021, "Breast Cancer Awareness Month" still fails to provide balanced information
In October 2014, we had already reported on Breast Cancer Awareness Month's commercialization and the missing or misleading figures on benefits and harms. In October 2021, it's the same. In a society where people argue about gender stereotypes, at the same time, they tolerate the practice of withholding the scientific results about early detection from women. Women and women's organizations should be the ones to tear the pink ribbons and not tolerate this finally. Every woman should make her own informed decisions instead of being emotionally controlled by teddy bears and commercial interests.
Your contact for more information:
Prof. Dr. Gerd Gigerenzer Tel.: (030) 805 88 519
Sabine Weiler (Communications RWI), Tel.: (0201) 8149-213, firstname.lastname@example.org
Unstatistics author Katharina Schüller is also a co-initiator of the "Data Literacy Charter," which promotes comprehensive data literacy education. The charter is available at www.data-literacy-charta.de.
RWI - Leibniz Institute for Economic Research
RWI - Leibniz Institute for Economic Research (formerly Rheinisch-Westfälisches Institut für Wirtschaftsforschung) is a leading centre for economic research and evidence-based policy advice in Germany.
Harding Center for Risk Literacy
University of Potsdam-Faculty of Health Sciences
„Our aim is to study how people behave in risk situations. We believe that our work can contribute towards the ideal of a society that knows how to calculate risks and live with them."
Gerd Gigerenzer, Director