Objective: To evaluate the effectiveness of a rapid assessment zone (RAZ) to mitigate emergency department (ED) overcrowding.
Methods: Electronic databases, controlled trial registries, conference proceedings, study references, experts in the field and correspondence with authors were used to identify potentially relevant studies. Intervention studies, in which a RAZ was used to influence length of stay, physician initial assessment and patients left without being seen, were included. Mean differences were calculated and reported with corresponding 95% CIs; individual statistics are presented as RR with associated 95% CI.
Results: From 14 446 potentially relevant studies, four studies were included in the review. The quality of one study was appraised as moderately high; others were rated as weak. Two studies showed that a RAZ was associated with a reduction of 20 min (95% CI: -47.2 to 7.2) in the ED length of stay; in one non-randomised clinical trial (RCT), a 192 min reduction was reported (95% CI: -211.6 to -172.4). Physician initial assessment showed a reduction of 8.0 min; 95% CI: -13.8 to -2.2 in the RCT and a reduction of 33 min (95% CI: -42.3 to -23.6) and 18 min (95% CI: -22.2 to -13.8) respectively were found in two non-RCTs. There was a reduction in the risk of patient leaving without being seen (RCT: RR=0.93, 95% CI: 0.77 to 1.12; non-RCT: RR =0.68, 95% CI: 0.63 to 0.73).
Conclusions: Although the results are consistent, and low acuity patients seem to benefit the most from a RAZ, the available evidence to support its implementation is limited.