Realist inquiry: a new way to think about overcrowding interventions

Physician-focused throughput initiatives are intended to mitigate the effects of emergency department (ED) overcrowding. Our tertiary care academic hospital recently piloted an emergency physician leader role intended to improve throughput. Although a separate experimental evaluation of this initiative was undertaken, it was expected that such an evaluation could not alone provide the necessary information to inform 'how' the emergency physician leader intervention worked. The objective of this study was to conduct a realist evaluation of the emergency physician leader. Realist inquiry utilizes Context Mechanism Outcome configurations to determine the impacts of interventions that are often missed by quantitative analysis. Using a realist perspective, this study aimed to evaluate the emergency physician leader initiative's effects on throughput with the goal of building transferable lessons to the implementation of future interventions.

Semi-structured interviews with key stakeholders in the intervention were conducted and analyzed using thematic and template techniques specifically aimed at identifying Context Mechanism Outcomes.

13 interviews were conducted with physicians and nurses who identified contexts and mechanisms which promoted or impeded ED throughput. For example, in situations where there was a clear indication for imaging or management that could not be initiated within the scope of a nursing protocol, the emergency physician leader initiating these orders was felt to promote ED throughput. Conversely, in contexts where there was no nurse available to fulfill early orders, the emergency physician leader's initiation of orders was perceived to impede throughput.

This evaluation provides insights into the reasoning and behaviour of individuals involved in the emergency physician leader initiative and provides a systematic approach to unraveling its complex causal pathway. Knowledge of context-mechanism-outcome relationships may help implementers design and measure the impact of future physician-focused throughput interventions.