Characteristics and predictors of adult frequent emergency department users in the United States: A systematic literature review.

FEDUs are disproportionally sicker and are also heavy users of non-ED health care service providers. The limited data for non-ED health services use in facility-specific studies of FEDU may contribute to findings in such studies that complex and unmet needs from PCPs contributed to ED visits. This suggests the need for more comprehensive data analysis beyond a few sites that can inform systemic management approaches.