Dissecting a waiting list.

This study examines a list of 1,283 patients waiting for general and orthopaedic surgery in an outer London borough. In general surgery varicose vein and hernia surgery accounted for 60% of those waiting more than one year. Of those who had waited more than a year on the orthopaedic list 25% were waiting for knee replacement surgery. The average length of time spent waiting was 10 months, with some people waiting over 5 years. The impact of the numbers waiting a long time on aggregate waiting time was highlighted by weighting the numbers waiting by the months spent waiting. Analysis of urgency codes indicates that although there was a statistically significant relationship between urgency and the length of waiting time there were some anomalies. There was considerable inter-consultant variation in list size, waiting times and the case mix. Analysis of the flows onto the list and work done in one month showed that it would take a considerable time to clear some lists at present rates of activity. Disaggregated information such as this which explores the flows of patients on to and off of the lists is essential for the management of waiting lists and will become increasingly important as waiting lists become a feature of--'contracts'--service agreements, in the reformed NHS.