Clinicians’ intuitions about when terminally ill patients will die are often inaccurate

Research funded by Marie Curie has revealed that a simple method, routinely used by clinicians to help identify patients who may be approaching their last year of life, is frequently inaccurate.

The “Surprise Question” was developed as a way to recognise those patients who might benefit from palliative care. It typically asks clinicians to consider the question: “Would you be surprised if this patient died within the next 12 months?”  

The study, conducted by researchers at The Marie Curie Palliative Care Research Department at University College London (UCL), looked at 26 previously published studies comprising 25,718 predictions made by clinicians using the “Surprise Question” over a ten-year period.

The findings reveal that the accuracy of predictions varied considerably, with clinicians tending to over-predict the number of people whom they thought would die. Over half (54%) of those predicted to die within a specified time period, lived longer than expected.

Clinicians made inaccurate predictions about one third of the patients who did die. Overall, they were incorrect in a quarter (25%) of cases.

However, clinicians were considerably better at identifying which patients would survive rather than which patients would die. They were accurate in 84% of these cases.

There was some evidence to suggest that the Surprise Question was slightly more accurate when used with cancer patients rather than patients with other illnesses (79% accurate compared to 72%), supporting the idea that patients with a cancer diagnosis have a more predictable disease trajectory than other illnesses.

The Surprise Question forms part of the Gold Standards Framework proactive indicator guidance which is widely used in hospitals, hospices and General Practices to help identify patients who may be approaching the last year of life. This guidance is listed as an example of a suitable tool for assisting clinicians with timely identification of people approaching the end of life, in the National Institute for Health Care and Excellence (NICE) quality standards for end of life care. 

Incorrect identification of patients could mean that some miss out on palliative care which should be provided when a patient has been identified as terminally ill. If patients are being over-identified as terminally ill, they may be unnecessarily referred to services for which there are limited resources.

The researchers emphasise that the Surprise Question is not specifically designed or promoted as a way of predicting survival. The purpose of the Surprise Question is to raise clinicians’ awareness about which of their patients may benefit from palliative care. However, the findings of the study highlight the need to develop more accurate ways of identifying such patients.

Paddy Stone, Professor of Palliative and End of life care at the Marie Curie Research Department at UCL, explains:

“Clinicians are often, understandably, reluctant to make specific prognostic predictions and so the Surprise Question plays a role in encouraging them to identify those of their patients who may benefit from palliative or end of life care, without the need for a precise survival prediction.

“But while it does have some utility in this respect, it falls short as an accurate predictor of survival – in terms of over-identifying the number of people whom it predicts will die and missing a proportion of those who do go on to die – and therefore the search is on for more accurate ways to recognise when patients are dying, that are both more sensitive and more specific.”

The researchers at UCL have previously looked at the accuracy of clinicians when making specific predictions of how long patients are likely to survive. A study published last year revealed wide variation in accuracy, ranging from an underestimate of 86 days to an overestimate of 93 days.  The researchers had hoped to find that some doctors – for example, those who were more experienced or older – would be more accurate than others, but the review did not provide any clear evidence that this was the case.

The team are now carrying out further work to develop more accurate and objective ways of predicting survival. The team are also trying to understand the decision making processes underlying clinicians’ predictions, they wish to find out why some clinicians’ make more accurate predictions and whether it’s possible to learn from these experts and teach others to be more precise. 

Professor Bill Noble, Medical Director for Marie Curie, explains:

“An accurate prognosis concerning the length of a terminal illness can be a really difficult thing for clinicians to get right, even for people in the advanced stages. While we may be able to improve the accuracy of predictions, these will ultimately always be expressed in terms of risk of death within a particular time frame.  No two people are the same – every illness carries a variety of different possible outcomes depending on the individual and the treatment they are receiving.

“Even if we are unable to provide a definitive answer in terms of how long someone has left to live, simply being able to recognise that they have a terminal illness, means that as clinicians, we can do much more to help people plan ahead. This usually involves finding the right time to have open and honest conversations with patients and their families about what to expect so they can make more informed choices about their future care options.

“Pain and other symptoms associated with terminal illnesses require treatment regardless of whether someone lives days, weeks or months.  What is important is that clinicians provide the best possible palliative care based on the individual’s need, regardless of how long they expect them to survive.”

The research article is published in the journal BMC Medicine  .