Computer systems do not necessarily improve diagnoses in the emergency department

Diagnostic errors are one of the greatest risks in emergency medicine. Hundreds of thousands of patients worldwide are misdiagnosed every year, often with serious consequences. To support doctors and facilitate diagnostic processes, computerised diagnostic decision support systems (CDDSS) are now used in many emergency departments in Switzerland. A study led by Wolf Hautz (University of Bern) has now shown that in practice, CDDSS do not bring about a measurable improvement in diagnoses nor an advantage for patients.However, they do influence the work of doctors in other ways.

The most important findings

In a large-scale study of over 1,200 patients in four Swiss emergency departments, the research team made diagnoses with CDDSS support for half of the patients and according to standard practice for the other half. The study included patients with abdominal pain, fevers from unknown causes and unspecific complaints because these are symptoms that are often misdiagnosed.

The result: in both groups, around 18 percent of patients experienced a so-called ‘diagnostic quality risk’ - i.e. an incorrect or subsequently corrected diagnosis, an unexpected admission to the intensive care unit or a new consultation within 14 days. There was no difference between the groups in terms of mortality, costs or length of stay. It was also surprising that the systems were often used differently in practice than expected: Doctors tended to use them to confirm their own hypotheses rather than to discover new differential diagnoses.

Significance for policy and practice

The results make it clear that computerised diagnostic decision systems do not automatically lead to better results. However, CDDSS can influence the diagnostic process by changing the behaviour of medical professionals - for example, young doctors are less likely to consult with more experienced colleagues.

The study’s findings show that computerised diagnostic decision systems change both medical processes and the relationship between patients and doctors. In order to reduce diagnostic errors, digital diagnostic systems should be introduced with an awareness of the limits of the technology and with a holistic view of people, processes and interactions.

Three main messages:

1. Diagnostic errors are frequent and have significant consequences in emergency medicine.

2. Computerised diagnostic decision support does not currently improve diagnoses made in emergency medicine.

3. Computerised diagnostic decision support impacts the diagnostic process in unexpected ways. It makes trainees less likely to seek advice, and its reliability and application vary significantly depending on the physician and the context.

Find out more about the methodology used by the researchers and further background information on the NRP 77 project website:

You will find further research projects on the topic of digital transformation conducted as part of the National Research Programme NRP 77 here: