'Difficult' patients increase doctors' misdiagnosis risk regardless of case complexity

This is because the mental effort needed to deal with the problematic behaviour distracts from the task at hand--processing the clinical information correctly--concludes a companion study in the journal.

It is assumed that a doctor's response to patients regarded as 'difficult' could affect the accuracy of the diagnosis s/he makes, but to date there's been no empirical evidence to back that up.

The researchers therefore set about testing this by providing 63 doctors in the last year of their specialty training in family medicine with one of two versions of six clinical case scenarios. One version portrayed a 'difficult' patient with one of six conditions and the other described the same patient, but without the disruptive behaviour (neutral).

The difficult behaviours portrayed included a demanding patient; an aggressive patient; one who questions the doctor's competence; one who ignores the doctor's advice; one who doesn't expect the doctor to take him seriously; and one who is utterly helpless.

The six conditions comprised: pneumonia; a blood clot in the lung (pulmonary embolism); brain inflammation (meningoencephalitis); overactive thyroid (hyperthyroidism); appendicitis; and inflammation of the pancreas caused by excess alcohol (acute alcoholic pancreatitis).

The latter three cases were deemed to be more complex. All included a brief description of the patient's medical history, their signs and symptoms, and the findings of the physical examination.

The doctors were asked to write down the most likely diagnosis as quickly as possible and then to review the same case, writing down the information for and against the diagnosis they had made, and to offer an alternative if they had got it wrong first time around.

Finally, they were asked to rate the likeability of the patient, using a validated (Likert) scale.

The results showed that not unexpectedly, diagnostic accuracy was higher for simpler cases. But the doctors were 42% more likely to misdiagnose a difficult patient than a 'neutral' one in a complex case, and 6% more likely to do so in a simple case.

The findings held true, irrespective of the time spent on diagnosis. Similarly, further reflection improved diagnostic accuracy, but it didn't make up for the impact of disruptive behaviours.

The average likeability ratings were significantly lower for patients portrayed as 'difficult' than they were for those portrayed as behaving neutrally.

In the second study 74 trainee hospital doctors were asked to diagnose eight clinical case scenarios, half of which involved difficult behaviours and half of which involved neutral behaviours.

The additional behaviours in this study included a patient who threatens the doctor and one who accuses the doctor of discrimination.

After making the diagnosis, the doctors were asked to recall the clinical findings and behaviours of each patient.

Diagnostic accuracy was 20% lower for difficult patients, even though the time spent on diagnosis was similar. The doctors also recalled proportionally fewer clinical findings (30% compared with 32.5%) and more behaviours (25% compared with 18%) in these patients.

This suggests that the mental energy needed to deal with the problematic behaviour interferes with processing the clinical information correctly, say the researchers.

They accept that vignettes don't necessarily reflect real doctor-patient interactions, and therefore clinical practice. But the potential negative impact of difficult behaviours is likely to be stronger in real life, they suggest.

And they nevertheless conclude that although the prevailing view is that doctors should be above reacting in this way to difficult patients..."the fact is, that difficult patients trigger reactions that may intrude with reasoning, adversely affect judgements, and cause errors."

They suggest that efforts should be made to boost medical students' and doctors' awareness of this.

In a linked editorial, Drs Donald Redelmeier and Edward Etchells of the Centre for Quality Improvement and Patient Safety, University of Toronto, Canada, say the results echo previous analyses, suggesting that unpleasant people tend to have more unfavourable outcomes.

They suggest that doctors should engage in more reflection, teamwork, and consultation and consider checklists or computer assisted diagnostics to mitigate the effects of difficult behaviours on diagnostic accuracy.