Dickson et al (2009), described the effects of Lean, a process improvement strategy pioneered by
Toyota, on quality of care in 4 emergency departments (EDs). Participants in 2 academic and 2
community EDs that instituted Lean as their single process improvement strategy made
observations of their behavioral changes over time. They also measured the following metrics
related to patient flow, service, and growth from before and after implementation: time from ED
arrival to ED departure (length of stay), patient satisfaction, percentage of patients who left without
being seen by a physician, the time from ordering to reading radiographs, and changes in patient
volume. The results showed that length of stay was reduced in 3 of the EDs despite an increase in
patient volume in all 4. Each observed an increase of patient satisfaction lagging behind by at least a
year. The narratives indicate that the closer Lean implementation was to the original Toyota
principles, the better the initial outcomes. The immediate results were also greater in the EDs in
which the frontline workers were actively participating in the Lean-driven process changes. In
conclusion, Lean principles adapted to the local culture of care delivery can lead to behavioral
changes and sustainable improvements in quality of care metrics in the ED. These improvements
are not universal and are affected by leadership and frontline workforce engagement. [8].