How accurate are waiting time perceptions of patients in the emergency department?

Study objective: To assess the ability of patients to accurately estimate specific waiting times in the emergency department. Methods: A questionnaire was administered by telephone to a random sample of 776 patients (or parents or responsible caretakers, if appropriate) who had been treated within the previous 2 to 4 weeks in the ED of a suburban hospital. Respondents were asked their perceptions of two particular time frames: (1) the time elapsed from triage until initial examination by the emergency physician (physician waiting time [PWT]), and (2) the time elapsed from triage until departure from the ED (total waiting time [TWT]). Corresponding actual times were extracted from a computerized database. Time frames were divided into discrete periods for comparison. The correspondence between actual and perceived times was assessed by optimal data analysis. Results: Only 22.3% of the respondents accurately estimated PWT. Although this level of accuracy is statistically significant (P<.0001), it reflects only 11% of the theoretically possible improvement in accuracy beyond chance. More respondents over estimated than underestimated PWT (49.9% versus 27.8%, respectively). In contrast, TWT was accurately estimated by 36.6% of the respondents (P<.0001), reflecting 18% of the theoretically possible improvement in accuracy beyond chance. Fewer respondents overestimated than underestimated TWT (24.5% versus 38.9%, respectively). Conclusion: Patients are not very accurate in their estimation of actual waiting times. Although fewer than one fourth of the respondents overestimated the TWT spent in the ED, almost half the respondents overestimated the PWT.