About Us


Franz Porzsolt, MD, PhD
German hematologist, evidence-based medicine expert, author of the book Optimising Health, Researcher and Professor of Surgical Department in Ulm University, president of Institute of Clinical Economics.

Luis Correia, MD, PhD
Brazilian cardiologist, evidence-based medicine expert, editor of the blog Medicina Baseada em Evidências, Associate Professor of Medical and Public Health School of Bahia and Scientific Director of Hospital São Rafael in Bahia.

Mission: To promote the scientific thinking in medicine, which is application of clinical epidemiology, but also the cognitive training in order to avoid bias and consider perceptions toward patient’s benefit.


Vision: A growing community that incorporates and promotes scientific thinking in medicine.



Sunday, August 14, 2016

Shots in the Olympia Shopping Centre Munich: The risk cycle.



Franz Porzsolt

Shortly before 6 pm on 22 July 2016, shots were heard in the Olympia shopping centre in Munich. Nine bystanders were killed and 23 were injured. These were the violent actions of an 18-year-old. He was found dead two hours later one kilometre from the scene of the crime as the tenth victim. Social networks immediately started spreading what was initially unreliable and unclear information, followed by ongoing reports in the media in which the few facts and a great deal of speculation were very difficult to tell apart.

In a very short time, an impressive contingent of police cars, fire trucks and ambulances arrived, making itself clearly seen and heard, streets were blocked off, traffic ground to a halt, public transport was stopped, the main railway station in Munich was evacuated, special units made their way towards Munich and individuals and hotels offered free accommodation to those affected by the lockdown. In Munich and Berlin, crisis meetings were called over the weekend. Offers of help came from around the world. Threats were to be eliminated, people were to be protected and lives saved. Everyone was frightened.


Fear was the main feeling. It was like a blitz attack – triggered not by shots but rather by information. A massive quantity of information was thrown at a sensitised society. It had been sensitised by the recent killings in Paris, Brussels and Nice and the pseudo-terrorist attack in Würzburg. The only calm influence on 22 July in Munich was the police spokesman who instilled confidence and radiated calm. He certainly gave out less information than most reporters.

A year ago, the Hanns Seidel Foundation (HSS) issued a call for more discussion about domestic security as a result of the increase in burglaries. The shooting rampage in the Olympia shopping centre is considerably more violent than burglary. Nevertheless, no-one can predict what will happen in the weeks ahead. Less terror, overreactions, a society inured to such events, panic? Following the HSS debate, there were discussions about which ideas regarding risks and safety should be taken up and further developed.

We should ask ourselves whether more bad than good came out of the incredible density of information produced by the massive contingent of police and emergency personnel, the collapse of road and rail traffic systems and the reports on the radio and television. Social media played a critical role, appearing almost uncontrollable. Is it really though? Most activities were done in the conviction of doing something essential in a tense situation. What damage would have resulted if the shots in the Olympia shopping centre had only been heard by a few people and the city of a million people had only learnt of the rampage several hours later? What would there have been to discuss if the incident at the Olympia shopping centre had actually been a terrorist attack and the perpetrator(s) had been able to reach other parts of the city?

The initial uncertainty was clarified a few hours after the violent actions and the existing risks properly assessed. It is easy to talk after the event but the details can also be analysed in hindsight. The relationship between the current existing and objective risk, its perception, the resultant reaction and feedback on the change to existing risks can be illustrated with a risk cycle.



This cycle is based on the assumption that in reality no-one makes decision based on objective risks. We all make decisions based on our subjective perception of objective risks. This statement in the risk cycle, that our decisions depend not on objective criteria but rather on subjective perceptions, may raise eyebrows among scientists because it is scientists in particular who believe that they make decisions based on objective criteria. This subjective perception of objective risks – we call it ‘perceived safety’ – is influenced by two different types of factors, on the one hand the largely constant factors such as personality traits and on the other the highly variable factors such as the available information.

However, the risk cycle also includes another significant element, which is the influence of subjectively driven behaviour on the modulation of the objective risk. In other words, our actions, which are driven by perceived safety, affect objective risks, which ultimately means no less than our decisions and thus the risk we are exposed to being extremely easily influenced by, for example, personality traits and information.

It is not the function of this brief history to clarify the details of the risk cycle. But this much must be emphasised: every single event that we encounter requires a careful and comprehensive analysis. We have already learned that decisions in situations of maximum uncertainty are associated with a considerable risk of errors. In a period marked by maximum uncertainty, acting on a principle of ‘perceived safety’ is the top priority until sufficient information is available for decisions that are largely rational. ‘Perceived safety’ cannot, however, be equated with a police presence, flashing lights and wailing sirens. The behaviour of the police spokesman came very close to this goal using the simplest means.

In conclusion, it should also be noted that the principle of perceived safety and the central importance of information were derived from medicine and now return to medicine via domestic politics: As patients, we all want to feel safe in the doctor’s surgery and in the hospital. Perhaps management in some surgeries and clinics can be improved with this concept. Our blog aims to encourage critical reflection.