Prognosis and prediction of outcome in comatose head injured patients

Recent studies on the prognosis of comatose head injured patients have identified single powerful prognostic features at various time points during the first month after onset of coma. Using appropriate statistical methods even more powerful combinations of prognostic features can be selected. At each time point, optimal prediction requires sets of only 3 to 5 features. These features include depth and duration of coma as assessed by the Glasgow Coma Scale, pupil reactivity to light, age in decades, and spontaneous and reflex eye movements. In individual new patients, bedside predictions are now possible, e.g. using a booklet with prognosis tables like the one used in Rotterdam. Doctors actually learn by using these tables as they retain some of the information. However, the main application is that these tables permit one to evaluate whether differences in survival rates in different centres with different management regimes are due to a difference in management efficacy or to a difference in initial severity of injury.