Who Improves the Operating Room? Professional Role Attribution and Process-Metric Reporting in Lean Six Sigma Perioperative Interventions: A Systematic Literature Review

Abstract

Purpose — Lean and Lean Six Sigma (LSS) are widely reported to improve operating room (OR) efficiency, yet it remains unclear which professional groups drive these gains and whether the interventions report the process metrics that define the Six Sigma method. This review examines the effect of Lean, Six Sigma and LSS interventions on OR turnover time and OR utilization, and systematically audits how the literature attributes implementation leadership and reports process capability metrics.
Design/Methodology/Approach — A systematic literature review following PRISMA 2020 reporting conventions. A semantic search of 138 million records was executed through twenty structured queries, returning 4,000 records; 1,357 duplicates were removed and 2,643 abstracts were screened against four eligibility criteria. Full-text screening applied three additional criteria. Twelve studies published between 2013 and 2024 met all criteria and entered structured extraction across twenty fields, including leadership attribution and process-metric reporting. Heterogeneity in outcome definitions precluded meta-analysis; synthesis follows the SWiM guideline.
Findings — Six studies reported measured pre-post turnover time, with reductions ranging from 0.2 minutes (−1.2%) to 23 minutes (−62.2%). Reduction magnitude tracked intervention breadth and baseline level rather than the specific Lean tool applied. OR utilization was reported in only three studies, in conflicting directions, with no statistical testing. Three reporting gaps were pervasive: no study reported process sigma or defects per million opportunities (0/12); eight of twelve attributed leadership to a multidisciplinary team without identifying a lead, and none was led by perioperative nursing or surgical technologists/scrub practitioners; and no study compared outcomes by professional role. Scrub practitioners appeared as team members in six studies, as affected staff in two, and were absent from four.
Research Limitations/Implications — Full text was unavailable for 205 of 251 otherwise-eligible records, which constrains the evidence base and may bias it toward open-access reporting. All included studies were observational and ten lacked concurrent controls. The absence of sigma-level reporting in studies self-labelled as Six Sigma or DMAIC raises a construct-validity question for the field: interventions are labelled by method but evaluated by outcome proxies unrelated to process capability.
Practical Implications — Organisations should specify and record role-level accountability when designing perioperative LSS projects, and should harmonise turnover-time definitions before benchmarking. The findings bear directly on task design in resource-constrained health systems, where reallocating turnover activities to surgical instrumentation professionals is a plausible but entirely untested lever.
Originality/Value — This is, to the authors' knowledge, the first review to treat leadership attribution and process-metric reporting in perioperative LSS as objects of systematic audit rather than as background description. It documents that the professional group most directly engaged in OR turnover activity has never led a published improvement intervention in this literature.