Objective and Background The percentage of patients who leave the Emergency Department (ED) before clinical assessment is one of the ED Quality Indicators. A rate of >5% is considered as a marker of potential risk, of overcrowding and long waits to be seen. The study objective is to establish our Left Before Treatment (LBT) rate and to review data trends in order that potential risks are identified.

Methods A retrospective ED notes review from the Ulster Hospital ED during May and June 2011. The ED notes of all patients who did not wait for assessment were collected and hand-reviewed by the authors.

Results There were 13 939 patient attendances to the ED during the 2-month study period. The Male: Female ratio was 0.9:1; mean age was 41 years, and 3305 (23%) were admitted to hospital. 342 (2.5%) patients LBT. Patients who LBT had a M: F ratio of 1.2:1; mean age of 34 years; and attended in the following pattern: 174 (51%) at the weekend; 90 (26%) on Monday or Tuesday (our busiest days). 171 (50%) attended when there was no ED Consultant present; 30 (9%) when there was also no middle grade. The LBT could be grouped into broad case-categories: Minor injury (22.8%), Medical (18.4%), Paediatric (13.2%), Head injuries (10.5%), atraumatic musculoskeletal (8.5%), Surgical (6.7%), unknown (5.8%). Mean time to triage was 21 min, 43 (12.5%) left before triage. 50 (14.6%) had investigations performed. 19 (38%) were abnormal; 1 (0.2%) patient required recall. 12 (3.5%) patients re-attended during the 2 months, some on multiple occasions.

Conclusion The Ulster ED LBT rate for May/June 2011 was 2.5%, meeting the QI standard. Detailed review reveals that the rates of re-attending and of significant pathology are insignificant (both <0.1% total attendances). We confirm that when the LBT rate is low detailed review is unnecessary, as clinical risk is insignificant. We will re-audit this topic locally.