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What is evidence-based medicine?

Created: ; Last Update: September 8, 2016; Next update: 2020.

Making the right decisions when it comes to medical issues is sometimes difficult, even for specialists: What advantages and disadvantages does a treatment or diagnostic test have? Is it even necessary and are there any alternatives? Evidence-based medicine (EBM) seeks reliable answers that can help you find the treatment that is right for you. It is based on scientific proof, and not just theories or expert opinions.

If you're ill, you'll usually want to get better as soon as possible. Ideally that will simply happen without you having to do anything, and your body will fight off the illness on its own after a few days. But medicine can often help to speed up recovery or avoid complications. Whether having treatment is better than waiting it out depends on a number of different factors: What are the chances of a treatment leading to a faster recovery? Is it likely to cause side effects? Could complications develop if you don’t have treatment?

Patients, as well as doctors and other healthcare professionals, need information they can depend on in these sorts of situations to make the best decisions possible. This is the purpose of evidence-based medicine (EBM): to provide healthcare professionals, patients and those close to them with up-to-date and scientifically proven information on the various medical options that are available to them. It can help to find out what sorts of advantages or disadvantages a treatment or test has, when people might benefit from it and whether it might also be harmful.

EBM uses special methods that it has developed to find the highest quality evidence for the benefits of a specific medical intervention. This evidence can be found in conclusive scientific studies. EBM also plays a part in making sure that the research that is done can help patients to answer the most important questions. This means that studies look into both the benefits of a treatment as well as how it affects quality of life, for example.

Gathering information and making a decision

In addition to information gained from studies, the knowledge and experience of medical experts is still very important: In practice, a doctor, physiotherapist or caregiver has to decide whether and how the available scientific knowledge can be used to help an individual patient. An evidence-based approach also includes informing patients about the pros and cons of medical options so that they can actively be part of the decision.

So making a treatment decision in accordance with EBM means basing it on the best available knowledge from clinical research and medical practice. A number of factors play an important role in the decision. As well as the type and severity of the health problem, these include the person's general life situation, personal values and opinions.

Generating and collecting knowledge: the EBM methods

So many medical publications appear worldwide every day that it is no longer possible for an individual medical professional to keep up with the latest state of knowledge. In order to offer support and to encourage new medical research, EBM provides a toolbox of different methods. These tools can be divided into three categories:

  • The first category includes methods that serve to create reliable new knowledge: Someone who would like to compare the advantages and disadvantages of different drugs, for example, will find suitable types of studies here.
  • The second category involves methods that help to summarize the existing knowledge on a subject: They serve to find and select the previously published studies that are best able to answer a particular question. There are now networks of researchers that specialize in looking for the latest research findings and summarizing them to provide easily accessible information.
  • The third category covers methods for presenting information to medical professionals and laypeople in a way that helps them to find, understand and make use of it.

The main aim is always to find out what kind of care is most suitable for a particular patient – and how to incorporate their individual preferences and circumstances into the treatment decision.


  • Evans I, Thornton H, Chalmers I, Glasziou P. Testing Treatments. German edition: Gerd Antes (ed.). Wo ist der Beweis? Plädoyer für eine evidenzbasierte Medizin. Bern: Huber; 2013. Download​.
  • Sackett DL., Rosenberg W., Muir Gray JA. et al.. Evidence-Based Medicine: What it is and what it isn't. BMJ 1996; 312:71-72. [PubMed: 17340682]
  • IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

    Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. We do not offer individual consultations.

    Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

© IQWiG (Institute for Quality and Efficiency in Health Care)
Bookshelf ID: NBK279348


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