title: Scaling Lean in primary care: impacts on system performance.
abstract: OBJECTIVE
  We examined a wide range of performance outcomes after Lean methodology-a leading strategy to enhance efficiency and patient value-was implemented and scaled across all primary care clinics in a nonprofit, ambulatory care delivery system.
  
  
  METHODS
  Using a stepped wedge approach, we assessed changes associated with the phased introduction of Lean-based redesigns across 46 primary care departments in 17 different clinic locations. Longitudinal analysis of operational metrics included: workflow efficiency, physician productivity, operating expenses, clinical quality, and satisfaction among patients, physicians, and staff.
  
  
  METHODS
  We used interrupted time series analysis with generalized linear mixed models to estimate Lean impacts over time. Projected outcomes in the absence of changes (ie, counterfactuals) were compared with observed outcomes after Lean redesigns were implemented, and mean differences were assessed using 95% bias-corrected bootstrap confidence intervals (CIs).
  
  
  RESULTS
  We observed systemwide improvements in workflow efficiencies (eg, 95% CI, 5.8-10.4) and physician productivity (95% CI, 3.9-27.2), with no adverse effects on clinical quality. Patient satisfaction increased with respect to access to care (95% CI, 15.2-20.7), handling of personal issues (95% CI, 2.1-6.9), and overall experience of care (95% CI, 11.0-17.0), but decreased with respect to interactions with care providers (95% CI, -13.4 to -5.7). Departmental operating costs decreased, and annual staff and physician satisfaction scores increased particularly among early adopters, with key improvements in employee engagement, connection to purpose, relationships with staff, and physician time spent working.
  
  
  CONCLUSIONS
  Lean redesigns can benefit primary care patients, physicians, and staff without negatively impacting the quality of clinical care. Study results may lead other delivery system leaders to innovate using Lean techniques and may further enhance support for Lean learning among public and private payers.
authors.affiliation: Palo Alto Medical Foundation Research Institute, 2350 W El Camino Real #447, Mountain View, CA 94040. E-mail: hungd@pamfri.org.
authors.forename: Dorothy Y
authors.initials: DY
authors.lastname: Hung
authors.forename: Michael I
authors.initials: MI
authors.lastname: Harrison
authors.forename: Meghan C
authors.initials: MC
authors.lastname: Martinez
authors.forename: Harold S
authors.initials: HS
authors.lastname: Luft
mesh_terms: D000554:Ambulatory Care Facilities / Q000458:organization & administration*; D017598:Efficiency, Organizational; D006801:Humans; D065186:Interrupted Time Series Analysis; D007588:Job Satisfaction; D017060:Patient Satisfaction; D011320:Primary Health Care / Q000458:organization & administration*; D058996:Quality Improvement; D017749:Total Quality Management; D057188:Workflow