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$.$ a study by Chang et al$.(2013)$ found that implementing Lean principles in a hospital emergency department significantly reduced waiting times and improved patient satisfaction.

$.$a study by Pugh et al$.(2012)$ found that implementing Lean principles in a hospital operating room significantly reduced turnover time and increased productivity.

$.$a study by Pronovost et al$.(2006)$ found that implementing a Lean$-$based checklist for central line insertion significantly reduced central line$-$associated bloodstream infections.