Extent and determinants of error in doctors' prognoses in terminally ill patients: prospective cohort study
Many doctors inaccurately predict prognoses for terminally ill patients and most overestimate how long patients will survive, find researchers from Chicago in this week's BMJ. This overestimation is important because it may lead to late referral of patients for hospice care and have implications for the quality of their remaining life.
Professor Nicholas Christakis and Dr Elizabeth Lamont from the University of Chicago Medical Center studied the prognoses provided by 343 doctors for 468 terminally ill patients (the prognoses were communicated to the researchers of the study and not the patients themselves). Of these prognoses, Christakis and Lamont found that only twenty per cent were accurate. Most predictions of survival (63 per cent) were overestimates and in general these overestimates suggested that patients would live five times longer than they actually did.
The authors say that their findings have several implications. Undue optimism about survival prospects may contribute to late referral for hospice care - patients should ideally receive hospice care for three months before death, but they typically receive only one month of care. They also suggest that doctors who do not realise how little time is left for their patient may miss the opportunity of improving the quality of their remaining life. Christakis and Lamont report that a patient's own conceptions of his/her future, based on a prognosis from his/her doctor is also affected, and given an optimistic outlook he/she may request futile, aggressive care rather than more beneficial palliative care.
Doctors who have less personal attachment to a patient tend to make more accurate prognoses and more experienced doctors make less prognostic errors, say the authors. Therefore they suggest that "second opinions" from a more experienced, detached source may be valuable.
Christakis and Lamont conclude that the bias towards optimism in doctors' prognostic assessments may be adversely affecting patient care.
Contact:
Professor Nicholas Christakis, Department of Medicine, University of Chicago Medical Center, Chicago Email: nchrista@medicine.bsd.uchicago.edu