Tag: Christakis and Lamont

Imminent Death: How Good Are Doctors’ Guesses?

This series of  posts continues to look at some fairly technical articles which nevertheless may be of use to you if you are facing the prospect of the imminent death of a family member or friend.

 This study,  “Extent and determinants of error in doctors’ prognoses in terminally ill patients: prospective cohort study”  by NA Christakis and EB Lamont first appeared in 2000 in the British Medical Journal [BMJ] in volume 320,  pages 469-472, but is available freely without university library access.

This is a summary of their findings:

What is already known on this topic

Doctors’ prognostic estimates are a central element of both patient and physician decision making, especially at the end of life

Doctors’ prognostic estimates in their terminally ill patients are often wrong and usually optimistic

What this study adds

A prospective cohort study of 504 terminally ill patients and their 365 doctors found that only 20% of the doctors’ predictions were accurate: 63% were overoptimistic and 17% overpessimistic

Multivariate modelling showed that most types of doctors are prone to error, in most types of patients

The greater the experience of the doctor the greater the prognostic accuracy, but a stronger doctor-patient relationship is associated with lower prognostic accuracy.

As one commentator on the study put it,

Doctors may be reluctant to acknowledge that patients they know well are close to death. This can be compounded by the patient’s and family’s preference to keep hoping for the patient to live longer. Those of us who know our patients longer often become attached to them. We, too, hate to admit that death is near.


Imminent Death: Best Guesses of How Much Longer

“Imminent death” is a search term that brings a lot of people to this blog. I am going to be adding more posts on this subject and collecting sources mentioned in a permanent page (as opposed to a post) as I go along.

One problem is that a lot of this material is in journals that you may not be able to look at for yourself because they are subscription only. The best way around this is to find someone enrolled in a college or university and ask to be allowed on via their ID/password. If you can get into a research library, and if the library still purchases hard copies of journals, that is another route. And it used to be true that if that library is a depository for government documents, you had to be admitted — at least to that area (but once in, well…). But that may no longer be true.

So one thing I’m going to do is to quote extensively here.

As I’ve noted before, it is surprisingly difficult for doctors or nurses to predict just how much longer a terminally ill person has left. This study, “Extent and determinants of error in doctors’ prognoses in terminally ill patients: prospective cohort study” [BMJ. 2000 Feb 19;320(7233):469-72] compared their doctors’ estimates for the time remaining to 468 terminally ill patients to the actual amount of time they survived. Authors Christakis and Lamont reported [emphasis added by me]:

Our study of 365 doctors and 504 hospice outpatients found that only 20% of prognoses were accurate. Most predictions (63%) were overestimates, and doctors overall overestimated survival by a factor of about five. These prognoses were doctors’ best guesses about their patients’ survival prospects, objectively communicated to the investigators and not to patients themselves. …  the tendency of doctors to make prognostic errors was lower among experienced doctors. Moreover, the better the doctor knew the patient-as measured, for example, by the length and recentness of their contact-the more likely the doctor was to err.

These findings have several implications. Firstly, undue optimism about survival prospects may contribute to late referral for hospice care, with negative implications for patients. …Doctors who do not realise how little time is left may miss the chance to devote more of it to improving the quality of patients’ remaining life. Secondly, to the extent that doctors’ …prognostic information affects patients’ own conceptions of their future, doctors may contribute to patients making choices that are counterproductive. Indeed, one study found that terminally ill cancer patients who hold unduly optimistic assessments of their survival prospects often request futile, aggressive care rather than perhaps more beneficial palliative care… Thirdly… disinterested doctors, with less contact with the patient, may give more accurate prognoses, perhaps because they have less personal investment in the outcome. Clinicians may therefore wish to seek “second opinions” regarding prognoses, and our work suggests that experienced doctors may be a particularly good source of opinion.

Some of the key points are summarized here.