An analysis of calls referred to the emergency 999 service by NHS Direct

NHS Direct was launched in West Yorkshire in April 1999. A 999 ambulance can be dispatched to the patient as a result of a call to NHS Direct. The aim of this study is to compare cases that had been referred by NHS Direct via the 999 service, with those who had dialled 999 themselves.

The study was carried out in three accident and emergency (A&E) departments in West Yorkshire, between 1 April 1999 and 21 August 1999. NHS Direct generated 999 calls were identified. The comparison group was selected at random from a list of all other 999 cases attending the three departments. The study involved retrieving basic demographic data, as well as duration of symptoms before dialling 999, triage category on arrival in A&E and disposal of patient. Ethical approval and statistical advice were obtained.

91 NHS Direct generated 999 calls were identified. Of the comparison group (260 cases), 28 were excluded from the study. There were no differences in the triage categories assigned to the two groups on arrival in A&E. There were notable differences in presenting complaint between the two groups and in particular, trauma was less common among the NHS Direct patients (6.6%) compared with those who had self dialled (37.5%). Patients who had first called NHS Direct were younger (p=0.033) and had endured their symptoms for longer (p<0.001); they were less likely to be admitted, and if discharged, were less likely to have follow up arranged (p=0.014).

Both groups received similar triage categories suggesting that severity of illness is equally well assessed by self as by NHS Direct. There are large differences in case mix between the two groups studied and these almost certainly explain the differences in outcome.