Existing scales or screening tools to predict risk of death and their domains
| CrisTAL Inclusion criteria and comments | ||||||
|---|---|---|---|---|---|---|
| Year/Author | Scale name and scoring | Components | Readily available | Clinical judgement | Value judgement | Sufficient for prognosis |
| 1949 Clark53 and modified by Péus55 | Karnofsky Performance Score (KPS) | Quality of life across the spectrum of health from 0=normal to 100=terminal | □ | ☑ | ✓ | □ |
| Administered face to face or by phone; involves value judgements; poor inter-rater reliability; does not cater for preadmission functional status | ||||||
| 1981 Addington-Hall54 | Spitzer Quality of Life Index | Five dimensions of quality of life: activity, daily living, general health, support of family and friends, and outlook | □ | □ | ☑ | □ |
| High clinician's acceptability as it takes 1 min to administer but has not proven accurate in predicting death within 6 months in individuals | ||||||
| 1985 Knaus64 1992 McMahon65 1995 DelBufalo66 2006 Zimmerman67 2013 Sharif47 | Acute Physiology and Chronic Health Evaluation APACHE II APACHE III APACHE IV APACHE-L | The point score is calculated from 11 ICU physiological measurements + age: Temperature (rectal), Mean arterial pressure, pH arterial, Heart rate, Respiratory rate, Sodium (serum) Potassium (serum), Creatinine, Haematocrit, White cell count, Glasgow Coma Scale | □ | ☑ | □ | ☑ |
| Used to predict hospital mortality in ICU. Unsuitable for admissions unit | ||||||
| 1987 Charlson68 1988 Pompei69 | Charlson Comorbidity Index (CCI) | Includes 19 categories of comorbidity and ach condition is assigned with a severity score of 1, 2, 3 or 6 depending on the risk of dying associated with this condition. Higher scores indicate greater comorbidity (patients with a score >5 have a 100% risk of dying at 1 year) | □ | ☑ | □ | □ |
| Complex calculation. Many adaptations attempted to improve predictive accuracy of 10-year mortality. Some capability for predicting short-term mortality. Does not cater for functional status or immediate risk of death, that is, physiological risk | ||||||
| 1993 Le Gal70 | SAPS II | Age, heart rate, Systolic BP, Temp, GCS, CPAP Y/N, PaO2, FIO2, urine Output, BUN, K, Bicarbonate, WCC, Chronic diseases, medical/surgical admission | □ | ☑ | □ | ☑ |
| Validated in 12 countries and the results were encouraging even in the absence of a primary diagnosis but high reliance on sophisticated testing not routinely conducted outside ICU | ||||||
| 1996 Anderson 71 2008 Virik and Glare72 | Palliative Performance Scale (PPS) | Assessment of observed ambulation, activity, evidence of disease, self-care, intake, level of physical activity and level of consciousness. Score 0=death Score 70=bed bound Score 100=full health and ambulation | □ | ☑ | ☑ | □ |
| Validated in Canada and Australia. However, the original intention of developers was not to use PPS for prognostication.71 Subjective observations do not contribute to standardisation of assessment Recent validation showed a PPS of 10 was associated with over 90% in-hospital mortality whereas a PPS of 70 was associated with 0% deaths | ||||||
| 1998 Elixhauser 73 2009 Van Walraven 18 2013 Austin74 | Elixhauser comorbidity Index | Relies on administrative databases to retrieve diagnostic items for 30 coexisting disease groups and applies weights to severity | □ | ☑ | □ | □ |
| Data items which are incomplete and not detailed enough to provide a clinically precise time of diagnosis. Complex to calculate, not too accurate on predicting mortality, more useful for researchers than clinicians at predicting length of stay | ||||||
| 2001 Subbe75 | MEWS | Scores of 5 or more were associated with increased risk of death | ☑ | ☑ | □ | ☑ |
| Good predictive ability for risk of death in busy acute services | ||||||
| 2004 Glare76 2012 Maltoni77 | Palliative Prognostic Score (PaP) | Karnofsky Performance Status plus Dyspnoea Anorexia White cell counts Clinician's weighted prediction of survival | □ | ☑ | □ | □ |
| Validated in Italy, Australia and England. Good association with short-term mortality but predictive value of tool affected by less experienced doctors | ||||||
2013 Kuo-H 79 | Rapid Emergency Medicine Score (REMS) | Blood pressure, respiratory rate, Glasgow Coma Scale, peripheral oxygen saturation, | ☑ | ☑ | □ | □ |
| Effective in predicting risk of death in hospital in conjunction with other clinical parameters including surgical treatment within 24 h. However, it has little relevance for elderly patients with chronic disease seeking hospital care | ||||||
| 2005 Rockwood58 | CSHA Clinical Frailty Scale | Scores of 1 (very fit) to 7 (severely frail) assigned by physician on the basis of qualitative definitions incorporating physical functioning and presence of comorbidities | □ | ☑ | ☑ | □ |
| Each 1-category increment of the frailty scale increased the risk of mortality. Largely subjective or reliant on clinical and value judgements | ||||||
| 2006 Paterson78 | SEWS | Respiratory rate, oxygen saturation, temperature, blood pressure, heart rate and conscious level | ☑ | ☑ | □ | ☑ |
| Score correlated both with in-hospital mortality and length of stay | ||||||
| 2006 Kellet 46 2012 Kellett80 | Simple Clinical Score (SCS) | Weighted cores derived from 16 independent variables: age, pulse, systolic blood pressure, respiratory rate, temperature, oxygen saturation, breathless on presentation, abnormal ECG, diabetes, coma, altered mental status, new stroke, unable to stand unaided, nursing home resident, daytime bed rest prior to current illness | ☑ | ☑ | □ | □ |
| Most items available and some easily obtainable. Successfully validated for 30-day and 1-year prediction but limited generalisability for many chronic conditions | ||||||
| 2008 Groarke81 | EWS | Pulse, systolic blood pressure, respiratory rate, oxygen saturation and neurological status. Increases in score indicate risk of complication or death | ☑ | ☑ | □ | ☑ |
| Used to identify physiological deterioration in patients on admission. Good predictor of transfer to high dependency care | ||||||
| 2008 Stone82 | Palliative Prognostic Index (PPI) | PPS + Oral intake Oedema Dyspnoea at rest Delirium | ☑ | ☑ | □ | □ |
| Developed for Japanese patients with advanced cancer in hospices and validated in Ireland in hospitals, hospices and the home. Prediction of positive predictive value of 86% for survival of less than three weeks PPV of 91% for survival of less than six weeks. Not generalisable to other conditions or longer term mortality predictions | ||||||
| 2008 Glare83 | Clinical Prediction of Survival (CPS) | Combines clinical experience with performance assessment | □ | ☑ | ☑ | □ |
| More accurate closer to death, overestimates survival if patient–doctor relationship is stronger | ||||||
| 2010 Prytherch 84 | ViEWS | Applies paper-based EWS score to a Vital Signs database and uses known relationship between deteriorated physiological measures and clinical outcomes such as in-hospital mortality with 24 h of the observations | ☑ | ☑ | □ | ☑ |
| It appears to predict immediate mortality well but vital signs databases are not widely available in many health systems | ||||||
| 2012 & 2013 Rothman44 56 | Rothman Index | Nurse-led assessment of whether minimum standards for each of 8 body systems, food intake, pain, risk of falls and 1 psychosocial (adequate support system)criteria are met or not met | □ | ☑ | ☑ | ☑ |
| Based on well-defined minimum standards as documented by nurses in electronic medical records in one USA hospital; independent of expert opinion; data not routinely available in other hospitals | ||||||
APACHE, Acute Physiology and Chronic Disease Evaluation; CSHA, Canadian Study of Health and Aging; EWS, early warning score; ICU, intensive care unit; MEWS, modified early warning score; SAPS II, Simplified Acute Physiology Score II; SEWS, standardised early warning scoring system; ViEWS, VitalPAC™ early warning score.