Determinants of non-urgent utilization of emergency departments: An observational study from California

Overuse of the hospital emergency department (ED) for non-urgent medical needs results in $38 billion annually in unnecessary costs to payers and is the third leading cause of health care waste in the United States. More than half of the 120 million annual visits to the ED nationally can be avoided without reducing health outcomes. The use of the ED for non-urgent problems also results in adverse non-financial consequences, such as overcrowding, lower quality and episodic care, and increased mortality and morbidity. Despite an extensive literature examining the determinants, costs and consequences of inappropriate ED utilization, most studies are difficult to translate into policy. Using a rich set of statewide health care data linked to patient sociodemographic information in California, we study the feasibility of reducing ED overutilization in the state by (1) analyzing the role of distances to federally qualified health centers from patient zip codes and the use of ED services for non-urgent medical conditions; (2) discovering predictors of inappropriate ED utilization based on observable patient characteristics; and (3) investigating the association between inappropriate ED utilization and subsequent inpatient admission patterns. The proposed study will address limitations in the generalizability of past research which did not include actual patient utilization data. With information derived from this study, policymakers can target the population most likely to use the ED for non-urgent illnesses and focus on areas where the potential for savings is the greatest.