Emergency department interventions and their effect on subsequent healthcare resource use after discharge: an overview of systematic reviews

Background
Due to the worldwide pressures on Emergency Departments (EDs), there is a focus on ED interventions to alleviate pressure. Ensuring interventions do not inadvertently impact upon other healthcare sectors is an important outcome. This overview of systematic reviews aimed to evaluate the impact of ED based interventions on subsequent healthcare resource use after ED discharge.

Methods
An overview of systematic reviews was conducted in accordance with the Cochrane Collaboration. Search criteria were devised using the PRESS standard and duplicate screening and extraction conducted for one third of systematic reviews. A primary study matrix was designed to reduce the impact of duplicate primary studies. Data was extracted in the form presented in the underlying review.

Results
After removal of overlapping primary studies, 38 systematic reviews and 213 primary studies were included. Overall confidence in the reviews was high in 12, moderate in seven, low in nine and critically low in 10 reviews. In the 38 reviews, 30 different intervention-population-resource use combinations were analysed. ED based interventions decreased subsequent healthcare resource use in 23.3% (n = 7/30) of the intervention-population-resource use combinations and had no effect in 40% (n = 12/30). The most common resource use reported was ED Revisit. The most common follow-up length from ED discharge was 12 months (n = 52/216), followed by the combined group of one month (n = 44/216).

Conclusions
ED based interventions decrease subsequent healthcare resource use in a fifth of population-intervention-resource use combinations. Future research should produce a standardised set of outcome measures for subsequent healthcare resource use.