To determine whether redesign of pathology processes, including indicators of sample priority, could reduce patient length of stay (LOS) in an emergency department (ED), and assess the long-term impact of two indicators of sample priority on pathology clinical performance indicators for ED samples.

Two observational studies of de-identified data from standard databases were conducted — a single-site pilot trial of patients attending the ED of one hospital compared with historical controls, and a multisite study of 132 521 full blood count (FBC) requests for patients attending seven EDs that utilised either of two pathology process changes (coloured specimen transport bags alone, or coloured specimen bags plus blood tubes with a priority indicator).

LOS in the ED was measured for the pilot trial, and collected-to-validated times for FBCs that fulfilled computer algorithm validation rules were measured for the multisite study.

In the pilot trial, the redesigned pathology process resulted in a 29-minute reduction (15.6%) in the median ED LOS for all patients (P < 0.001) compared with historical controls. In the multisite study, use of coloured specimen bags plus blood tubes with a priority indicator resulted in an 8-minute reduction (20.1%) in mean collected-to-validated times for FBC requests compared with FBC requests that used coloured specimen bags alone (P < 0.001).

Our pilot trial revealed a direct relationship between pathology process design and LOS in the ED, suggesting that redesigned pathology processes can significantly reduce LOS in the ED. Our multisite study showed that collecting samples directly into blood tubes with an incorporated priority indicator reduces pathology test turnaround times. These data suggest that LOS in the ED can be significantly reduced by simple changes to pathology processes, such as collecting samples directly into specimen containers with an incorporated priority indicator.