Study finds psychiatrists agree in only 55 percent of cases

Psychiatrists reached the same diagnosis in 54.9 percent of written patient cases in a new international study, according to DR. The findings show that doctors can assess the same symptoms differently, although the results cannot be directly transferred to Danish psychiatric practice.

The study involved 1,038 doctors from 19 countries. Each doctor assessed two of nine patient cases and assigned a diagnosis using the World Health Organization’s ICD-10 international diagnostic system.

The greatest disagreement concerned cases involving the schizophrenia spectrum. In some cases, doctors assessed the symptoms as either schizophrenia or obsessive-compulsive disorder, known as OCD.

“If a case included symptoms pointing towards schizophrenia as well as symptoms pointing towards OCD, we saw that the doctors were divided almost equally,” Julie Nordgaard, a professor of clinical psychiatry at the University of Copenhagen and a chief physician, told P1 Morgen.

However, the findings do not mean that half of all patients receive an incorrect diagnosis. The study examined doctors’ agreement on written cases, not how often two psychiatrists give different diagnoses to the same patient in real life.

“I clearly recognise that there can be uncertainty in the diagnostic process,” practising psychiatrist Casper Westergaard told P1 Morgen. “But I do not recognise a situation in which half of all diagnoses are made incorrectly.”

The study found significant differences between the individual cases. For the case with bipolar disorder as the reference diagnosis, 94 percent of doctors chose bipolar disorder. For the OCD case, 92 percent chose OCD.

A psychiatric diagnosis can affect a patient’s medical treatment, psychotherapy, and access to services and support. Nordgaard said it was therefore important for patients to receive the right diagnosis.

Westergaard said a diagnosis should not be viewed as an unchanging truth, but as the best available explanation at a particular point in time. He also said psychiatry could not be expected to achieve 100 percent certainty because diagnoses are not established in the same way as, for example, a condition identified through an X-ray.

Researchers behind the study said the continuing disagreement should be taken seriously. According to the University of Copenhagen, diagnostic uncertainty can affect both patient treatment and research into mental disorders.