The accuracy of clinician predictions of survival in the Prognosis in Palliative care Study II (PiPS2): A prospective observational study

Abstract

Background Prognostic information is important for patients with cancer, their families, and clinicians. In practice, survival predictions are made by clinicians based on their experience, judgement, and intuition. Previous studies have reported that clinicians’ survival predictions are often inaccurate. This study reports a secondary analysis of data from the Prognosis in Palliative care Study II (PiPS2) to assess the accuracy of survival estimates made by doctors and nurses. Methods and findings Adult patients (n = 1833) with incurable, locally advanced or metastatic cancer, recently referred to palliative care services (community teams, hospital teams, and inpatient palliative care units) were recruited. Doctors (n = 431) and nurses (n = 777) provided independent prognostic predictions and an agreed multi-professional prediction for each patient. Clinicians provided prognostic estimates in several formats including predictions about length of survival and probability of surviving to certain time points. There was a minimum follow up of three months or until death (whichever was sooner; maximum follow-up 783 days). Agreed multi-professional predictions about whether patients would survive for days, weeks or months+ were accurate on 61.9% of occasions. The positive predictive value of clinicians’ predictions about imminent death (within one week) was 77% for doctors and 79% for nurses. The sensitivity of these predictions was low (37% and 35% respectively). Specific predictions about how many weeks patients would survive were not very accurate but showed good discrimination (patients estimated to survive for shorted periods had worse outcomes). The accuracy of clinicians’ probabilistic predictions (assessed using Brier’s scores) was consistently better than chance, improved with proximity to death and showed good discrimination between groups of patients with different survival outcomes. Conclusions Using a variety of different approaches, this study found that clinicians predictions of survival show good discrimination and accuracy, regardless of whether the predictions are about how long or how likely patients are to survive. Accuracy improves with proximity to death. Although the positive predictive value of estimates of imminent death are relatively high, the sensitivity of such predictions is relatively low. Despite limitations, the clinical prediction of survival should remain the benchmark against which any innovations in prognostication are judged. Study registration ISRCTN13688211. http://www.isrctn.com/ISRCTN13688211.

Exploring the Potential Use of Wearable Devices as a Prognostic Tool among Patients in Hospice Care

“…Although all predicting tools for survival are insufficiently accurate in clinical use, the study still found high correlation between predicting tools and outcome. Stone et al (2022) further explored the accuracy of CPS in a large clinical study with 1833 patients in palliative care, 431 physicians and 777 nurses [36]. This latest article suggested that both professional groups were better than the chance of in survival prediction; especially, the performance of clinician was "very good" at predicting imminent death, not surprisingly corresponding to common understanding.…”

Factors Related to Accurate Clinicians’ Prediction of Survival: An International Multicenter Study in East Asia

“…Third, the median survival time was relatively short as a few weeks. The CPS may have been affected by the "horizon effect," which is a phenomenon whereby CPS is more accurate when death is more imminent [24] Fourth, various de nitions of the accuracy of CPS exist [25]. Thus, the factors associated with CPS accuracy may vary depending on which de nition is applied.…”

Prognostic evaluation in patients with advanced cancer in the last months of life: ESMO Clinical Practice Guideline

“…However, another study reported that predictions of death within the next 7 days were similarly accurate (79% and 77% for nurses and physicians, respectively). 3 The 3-day SQ is reported to have a sensitivity of 84%, specificity of 26%, PPV of 54%, negative predictive value (NPV) of 84% and overall accuracy of 59% ( N = 1411 patients with PPS ≤20%). 75 …”

“… 13 One study reported limited evidence in support of this recommendation; however, although statistically significant, the magnitude of improvement was very small (accuracy of nurse prediction 55.2%, accuracy of doctor prediction 56.3%, accuracy of team prediction 57.5%). 14 There is also evidence to support the existence of the so-called ‘horizon effect’, the phenomenon whereby CPS is more accurate when death is more imminent, 3 , 15 although not all studies have observed this phenomenon. 16 …”