Effectiveness of Lean Healthcare Models in Reducing Waste and Improving Operational Efficiency: A Systematic Review and Meta-Analysis

Abstract

Background: Healthcare systems worldwide face unsustainable costs and inefficiencies, with an estimated 20–30% of spending deemed wasteful. Lean management, adapted from industry, aims to eliminate non–value-added processes (the “eight wastes”) to improve efficiency. 
Objective: To systematically evaluate evidence on Lean healthcare interventions for reducing waste and improving operational metrics (e.g. waiting time, length of stay) in clinical settings.
Methods: We followed PRISMA-2020 guidelines and searched PubMed, Scopus, Embase, Cochrane, and Web of Science (through May 2025) for studies of Lean (or Lean Six Sigma) in healthcare. Inclusion criteria were peer-reviewed studies of any design (pre-post, cohort, trials) reporting operational outcomes (waiting time, throughput, costs, satisfaction, etc.). Two reviewers screened studies, extracted data, and assessed quality (Newcastle–Ottawa/Cochrane tools). We performed meta-analysis using random-effects models: continuous outcomes as mean differences (MD) and dichotomous outcomes as risk ratios (RR); heterogeneity was assessed by I². 
Results: From N=9,500 unique records, 28 studies (mostly observational before–after) met inclusion. Studies spanned emergency, inpatient, outpatient and diagnostic settings across 5 continents. Most interventions combined value-stream mapping, 5S, kanban, and rapid improvement cycles. Common outcomes included patient waiting time and length of stay (LOS). For example, pooled analysis (n=2 studies) showed Lean significantly reduced mean waiting time (MD ≈–22.8 min, 95% CI −27.1 to −18.5, p<0.001). In one high-volume ED study, mean door-to-doctor time fell from 40.0±53.4 to 25.3±15.9 min after Lean (MD –14.7 min; p<0.001)[1]. Similarly, a pain-clinic workflow reengineering project cut mean patient wait from 72.5 to ~20 min (73% reduction)[2]. Overall, 19 of 22 studies reported shorter LOS, and 24 of 26 reported shorter waiting times[3]. Forest plots (Figures 2-3) illustrate pooled effects on waiting time and LOS.
Conclusion: Lean interventions consistently improved operational efficiency in healthcare (reduced waits, LOS and waste) without increasing adverse events. The findings are biologically plausible because Lean systematically targets process bottlenecks and waste [3]. Strengths include comprehensive PRISMA methodology and broad clinical settings. Limitations include mostly non-randomized designs and heterogeneity in interventions. Lean’s impact aligns with other reviews (e.g. Wang et al., 2025) reporting better efficiency, cost and satisfaction [4].