Diagnosis of the vegetative state (VS) or minimally conscious state (MCS) is dependent on the presence or absence of behavioural variables. Diagnosis of the VS in the case of those who have had a severe head injury does not occur for several months after injury. If such outcomes could be predicted it would facilitate appropriate and timely referrals to specialist rehabilitation units. This paper describes a follow up study of patients observed prospectively after severe head injury and followed up four years later. Thirty patients had made a moderate or good recovery and eight met criteria for MCS. Analysis of early observations together with outcome data suggest that the duration of time taken to achieve some early behaviours may be predictive of poorer outcome.