- Paul Glare (), head of department1,
- Kiran Virik, research fellow1,
- Mark Jones, biostatistician2,
- Malcolm Hudson, professor3,
- Steffen Eychmuller, medical director4,
- John Simes, director2,
- Nicholas Christakis, professor5
- 1 Department of Palliative Care, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia
- 2 NHMRC Clinical Trials Centre, University of Sydney, Sydney, Australia
- 3 Department of Statistics, Macquarie University, Sydney
- 4 Department of Palliative Care, Kantonsspital, St Gallen, Switzerland
- 5 Department of Health Care Policy, Harvard Medical School, Boston, MA, USA
- Correspondence to: P Glare
- Accepted 12 June 2003
Objective To systematically review the accuracy of physicians' clinical predictions of survival in terminally ill cancer patients.
Data sources Cochrane Library, Medline (1996-2000), Embase, Current Contents, and Cancerlit databases as well as hand searching.
Study selection Studies were included if a physician's temporal clinical prediction of survival (CPS) and the actual survival (AS) for terminally ill cancer patients were available for statistical analysis. Study quality was assessed by using a critical appraisal tool produced by the local health authority.
Data synthesis Raw data were pooled and analysed with regression and other multivariate techniques.
Results 17 published studies were identified; 12 met the inclusion criteria, and 8 were evaluable, providing 1563 individual prediction-survival dyads. CPS was generally overoptimistic (median CPS 42 days, median AS 29 days); it was correct to within one week in 25% of cases and overestimated survival by at least four weeks in 27%. The longer the CPS the greater the variability in AS. Although agreement between CPS and AS was poor (weighted κ 0.36), the two were highly significantly associated after log transformation (Spearman rank correlation 0.60, P < 0.001). Consideration of performance status, symptoms, and use of steroids improved the accuracy of the CPS, although the additional value was small. Heterogeneity of the studies' results precluded a comprehensive meta-analysis.
Conclusions Although clinicians consistently overestimate survival, their predictions are highly correlated with actual survival; the predictions have discriminatory ability even if they are miscalibrated. Clinicians caring for patients with terminal cancer need to be aware of their tendency to overestimate survival, as it may affect patients' prospects for achieving a good death. Accurate prognostication models incorporating clinical prediction of survival are needed.
Contributors PG and JS participated in designing the review. PG, KV, and SE decided on trial inclusion or exclusion, extracted data, and assessed study quality. NC, KV, and SE checked the data and revised the manuscript, which was drafted by PG. MJ and MH did the statistical analyses. JS and NC were the principal advisers, guiding and interpreting the review. PG is the guarantor for the paper.
Competing interests None declared.
Ethical approval Not needed.