A Guide to Health and Medicine from the GIJN

5 June 2021

Cécile Bour MD


ReCheck is an independent investigative media specializing in the backstage  of health affairs and issues.

It was founded by two investigative journalists, Catherine Riva and Serena Tinari.

Catherine Riva, a Swiss investigative journalist, is the author (among others) of the book “La piqûre de trop”  on the anti-HPV vaccination, published by Xena, and of the Mammograben files on the mammography screening business in Switzerland. Catherine Riva was also one of the reviewers of our information leaflet.

Serena Tinari is an Italian investigative journalist who has (among other things) worked for the media Patti Chiari, a weekly news magazine on citizens’ and consumers’ rights of the Italian Swiss public television RSI.

In the past, we have relayed one of their programs [1] on mammography screening with a guest speaker, Professor Michael Baum, surgeon and professor emeritus (University College London), who is an advocate of informing women about the benefit/risk balance of mammography screening and has published [2] and taken positions in this regard.[3] [4] 

In addition to a different and, above all an independent approach to information, Re-Check also offers training and conferences on the investigations conducted by these two journalists, as well as access to GlobaLeaks, an anonymous platform for whistleblowers to transmit confidential information in the field of medicine and public health.

Novelty of Re-Check

This year’s novelty is the “A GIJN Guide. Investigating Health  and Medecine »  elaborated by Catherine Riva and Serena Tinari, for journalists covering health issues, in French version downloadable here.

GIJN is the acronym for the Global Investigative Journalism Network, a group of international journalists committed to the development and sharing of information and data among investigative journalists around the world, while promoting good journalism practices and open access to documents and data.

The guide

What is this guide and for what purpose? As explained on the homepage this guide addresses  the issues of « drug development and approval, evaluating scientific studies, understanding conflicts of interest, and exposing fraud and malpractice. It’s a road map for going beyond the claims of corporate press releases and government officials ».

Clearly, it is about unraveling the claims of medical “experts” and opinion leaders, and allowing journalists to decipher scientific studies. According to the two authors’ presentation, the creation of this guide appears to have been motivated by the difficulties encountered by journalists during the Covid pandemic, and their disarray in front of medical information that was developing at an unsustainable rate. The preface is specifically dedicated to this issue.

The guide consists of a preface, an introduction, five main chapters (Regulating drugs : Dévelopment and Approval, A study is not just a study. Get your numbers straightThe Scientific Basis of Influence, First do not harm. Reporting about safetyTips and traps, Hypes and Ethics) and appendices.

A study is not just a study. Get your numbers straight

This chapter, number 2, caught our attention because it is in line with the concerns of Cancer Rose.


It is reminded here that EBM, or evidence-based medicine, should be at the center of a journalistic investigation, applying the principle of critical reading (the process of carefully and systematically evaluating the results of scientific research on the basis of evidence, to judge its reliability, value and relevance).

Evidence-based practice should lead the investigator to assess the relevance of certain elements according to the PICO method (P = check whether the patient’s characteristics are suitable for the research being conducted; I = the treatment or test, e.g., screening; C = the comparator, which may be a placebo or another treatment or test; O = outcome, i.e., the measurement element or judgment criterion used in the study, which may be a rate of mortality, a rate of survival, a rate of serious illness, a therapeutic improvement, etc.)

It is interesting and even essential to be aware of this prerequisite in order to avoid analyses of studies as one can sometimes read in certain magazines or newspapers beginning with : “a large study concludes that…”, or “Professor X, an expert in the treatment of disease Y, believes that…”

Levels of evidence

This chapter also reminds us that not all mediated studies are equal, and present a remarkable diagram illustrating the hierarchy of studies according to the level of evidence, which is very useful for assessing the validity of a study.

Part of the chapter explains the temptation to confuse correlation with causality, a mistake very often made, not only by journalists but sometimes by doctors and scientists themselves. It is not because two events are concomitant that they are necessarily related by cause and effect.

Presentation of data

Good advice is given concerning the use of absolute values, rather than percentages, to judge the benefit-risk balance of a treatment or test.

In the area of breast cancer screening, which is our topic, there is a need to report the reduction in the risk of dying from breast cancer, in absolute values, rather than in relative values. We often underline this point and the French citizen consultation on breast cancer screening requested it in several parts of its report (e.g. page 79),

The mathematician Gerd Gigerenzer’s demonstration presented by the authors in this second chapter of the guide is a good and very masterful example of how a percentage can be misleading. When women are told that breast cancer screening will reduce mortality by 20%, they understand that 20 out of every 100 women screened will die of breast cancer. This is not the case. Gigerenzer writes « Did the public know that this impressive number corresponds to a reduction from about five to four in every 1,000 women, that is, 0.1%? The answer is, no. »
(But this misrepresentation still persists in official brochures and documents from official websites. [5] [6]  )

A concrete example of misleading communication in the field of breast cancer screening

The Grouvid study

In November 2020, the Grouvid study was published and mediatized. It was done by modeling a scenario in the context of the Gustave Roussy Institute, to evaluate the consequences of delays in oncology care for patients due to the Covid pandemic. We reported on this here, as well as on a meta-analysis published in the BMJ that also points in this same direction.

The Grouvid study, like the BMJ study cited, suggested that the delays in patient care linked to the first wave of Covid-19, could be responsible for an excess of cancer mortality of 2 to 5%, 5 years after the start of medical care. According to the study, these delays in medical care are due to 2 factors:

– the reluctance of patients to seek care for fear of contamination
– and a reduction in the capacity of hospitals to provide care.

Nowhere in this study was screening discussed, not breast cancer screening or any other screening.

However, the media made the confusion and abundantly relayed that delays in screening were the cause of excess mortality in oncology, and in particular for breast cancer [7] .  This was false information.


Investigating the healthcare industry can be really complex and difficult as a journalist.
Covering a health field, whatever it may be, certainly requires devoting a lot of time to it, training, acquiring specialized scientific notions, such as basic knowledge of epidemiology and statistics, and reading a lot of specialized literature, as well as mastering the scientific jargon.

The urgency in communication, the pressure of editorial offices on positive communication in the field of breast cancer screening, the self-censorship of some journalists lead to disasters in the information of populations, to their detriment.

We have seen the approximation and the misunderstanding in the medical information during the Covid-19 pandemic, due to the journalistic subject itself, certainly complex, but also aggravated by the urgency of the situation and the haste of the media to publish.

The tools proposed by the Global Investigative Journalism Network’s Guide to Investigating Health can only be a salutary asset for any journalist concerned with good health information, in order to avoid the confusion of the population in the face of an influx of information and counter-information, as we experienced during the pandemic, and to avoid exposing people to promising procedures or tests that will plunge them, through ignorance of the potential dangers, or through bad media coverage, into the hell of a disease.

It is a question of ethics, journalistic this time.



Harms from breast cancer screening outweigh benefits if death caused by treatment is included
BMJ 2013; 346 doi: https://doi.org/10.1136/bmj.f385 (Published 23 January 2013)Cite this as: BMJ 2013;346:f385

[3] https://cancer-rose.fr/2019/03/25/lettre-de-michael-baum-the-times/



[6] In this regard, read our article: methods of influencing the public to participate in screening

Reduction of breast cancer mortality only expressed as relative risk reduction by the French national screening agency in the 2019 information brochure, this represents a method of influence used by the authorities to increase participation in screening. The authors point out that the use of these types of influence remains ethically dubious in cancer screening programs where the benefit-harm ratio is complex and scientifically contested.

[7] Non-exhaustive list of all the media that relayed this information to the public in a misleading manner:









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