Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Multicenter Study
. 2008 Feb 23;336(7641):425-9.
doi: 10.1136/bmj.39461.643438.25. Epub 2008 Feb 12.

Predicting outcome after traumatic brain injury: practical prognostic models based on large cohort of international patients

MRC CRASH Trial Collaborators  1 ; Pablo Perel, Miguel Arango, Tim Clayton, Phil Edwards, Edward Komolafe, Stuart Poccock, Ian Roberts, Haleema Shakur, Ewout Steyerberg, Surakrant Yutthakasemsunt
Affiliations
Multicenter Study

Predicting outcome after traumatic brain injury: practical prognostic models based on large cohort of international patients

MRC CRASH Trial Collaborators et al. BMJ. .

Abstract

Objective: To develop and validate practical prognostic models for death at 14 days and for death or severe disability six months after traumatic brain injury.

Design: Multivariable logistic regression to select variables that were independently associated with two patient outcomes. Two models designed: "basic" model (demographic and clinical variables only) and "CT" model (basic model plus results of computed tomography). The models were subsequently developed for high and low-middle income countries separately.

Setting: Medical Research Council (MRC) CRASH Trial.

Subjects: 10,008 patients with traumatic brain injury. Models externally validated in a cohort of 8509.

Results: The basic model included four predictors: age, Glasgow coma scale, pupil reactivity, and the presence of major extracranial injury. The CT model also included the presence of petechial haemorrhages, obliteration of the third ventricle or basal cisterns, subarachnoid bleeding, midline shift, and non-evacuated haematoma. In the derivation sample the models showed excellent discrimination (C statistic above 0.80). The models showed good calibration graphically. The Hosmer-Lemeshow test also indicated good calibration, except for the CT model in low-middle income countries. External validation for unfavourable outcome at six months in high income countries showed that basic and CT models had good discrimination (C statistic 0.77 for both models) but poorer calibration.

Conclusion: Simple prognostic models can be used to obtain valid predictions of relevant outcomes in patients with traumatic brain injury.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None declared.

Figures

None
Fig 1 Relation between age and mortality at 14 days
None
Fig 2 Relation between Glasgow coma scale and mortality at 14 days
None
Fig 3 Calibration of basic models using expected and observed probabilities of mortality at 14 days (top) and death or severe disability at six months (bottom) in patient with traumatic brain injury according to income level of country. P value is for Hosmer-Lemeshow test
None
Fig 4 Calibration of computed tomography models using expected and observed probabilities of mortality at 14 days (top) and death or severe disability at six months (bottom) in patient with traumatic brain injury according to income level of country. P value is for Hosmer-Lemeshow test
None
Fig 5 Screenshot of web based calculator available at www.crash2.lshtm.ac.uk/. If CT scan available box is ticked, calculator displays additional CT variables
None
Fig 6 External validation of basic model for death or severe disability at six months in IMPACT database
None
Fig 7 External validation of CT model for death or severe disability at six months in IMPACT database
See this image and copyright information in PMC

Comment in

References

    1. Bruns J Jr, Hauser WA. The epidemiology of traumatic brain injury: a review. Epilepsia 2003;44(suppl 10):2-10. - PubMed
    1. Fleminger S, Ponsford J. Long term outcome after traumatic brain injury. BMJ 2005;331:1419-20. - PMC - PubMed
    1. Hofman K, Primack A, Keusch G, Hrynkow S. Addressing the growing burden of trauma and injury in low- and middle-income countries. Am J Public Health 2005;95:13-7. - PMC - PubMed
    1. Perel P, Wasserberg J, Ravi RR, Shakur H, Edwards P, Roberts I. Prognosis following head injury: a survey of doctors from developing and developed countries. J Eval Clin Pract 2007;13:464-5. - PubMed
    1. Lee KL, Pryor DB, Harrell FE Jr, Califf RM, Behar VS, Floyd WL, et al. Predicting outcome in coronary disease. Statistical models versus expert clinicians. Am J Med 1986;80:553-60. - PubMed

Publication types