To describe the socio-demographic characteristics and clinical outcomes of patients who leave the emergency department (ED) without being seen by a physician.

This 3-month prospective study was conducted at a downtown Toronto teaching hospital. Patients who left the ED without being seen (LWBS) were matched with controls based on registration time and triage level. Subjects and controls were interviewed by telephone within 1 week after leaving the ED.

During the study period, 386 (3.57%) of 10 808 ED patients left without being seen. One-third of these had no fixed address or no telephone, and only 92 (23.8%) consented to a telephone interview. They cited excessive wait time as the most common reason for leaving the ED (in 36.7% of cases). Despite leaving the ED without being seen, they were no more likely than those in the control group to seek follow-up medical attention (70 % in both groups). Among those from both groups who did seek follow-up, the LWBS patients were more likely to do so the same day or the day after leaving the ED. The LWBS patients often lacked a regular physician (39.1% v. 21.7%; p = 0.01) and were more likely to attend an ED or urgent care clinic (34.8% v. 12.0%; p < 0.001). Controls were more likely to follow up with a family physician (37.0% v. 23.9%; p = 0.06). The LWBS and control groups did not differ in subjective health status at 48 hours after leaving the ED, nor in subsequent re-investigation in hospital.

Patients who leave the ED without being seen have different socio-demographic features, methods of accessing the health care system, affiliations and expectations than the general ED population. They are often socially disenfranchised, with limited access to traditional primary care. These patients are generally low acuity, but they are at risk of important and avoidable adverse outcomes.