It sounds like a bad question upon first glance, but it’s a valid question that comes up frequently in healthcare in the context of improvement of clinical and other outcomes. While ‘Lean methods’ focus on optimizing performance of systems, ‘Quality Improvement (QI) methods’ fundamentally focus on testing interventions using Plan-Do-Study-Act cycles in order to effect improvement and also to learn which interventions worked and which interventions did not. The drivers behind the question are mostly related to choosing the best conceptual framework to guide improvement work, and secondly related to stewardship of available resources to do the improvement work. Asking this question is an interesting way to apply ‘lean thinking’ to the choice of methods for improvement work.

The white paper published by the Institute for Healthcare Improvement (Scoville R, Little K. Comparing Lean and Quality Improvement. IHI White Paper. Cambridge, Massachusetts: Institute for Healthcare Improvement; 2014. Available at ihi.org) addresses this question. The authors review the basic concepts and principles of Lean and QI, and discuss the similarities, differences and when their use is indicated in healthcare improvement. QI methods are rooted in the work done by Shewhart, Deming and Juran whereas Lean methods are rooted in the work done by Taiichi Ohno in Toyota industries and alternately called the Toyota Production System (TPS). It is notable that all of them did the vast majority of their work in the first half of the twentieth century.

When Lean or TPS principles are applied to healthcare, there are no medical errors; care is customized to each patient; there is no waste; and the healthcare workers are safe and secure in the workplace. Lean recognizes eight forms of waste in healthcare – confusion, inappropriate inventory, unnecessary motion, waiting, over-processing, over-production, incorrect work products or outcomes, and waste of intellect. The frontline workers, i.e., the clinicians who come in contact with the patients in healthcare, are in charge of inspecting while they work (jidoka) and continuously find ways to improve the work as it happens and mitigate problems (kaizen). The problem-solving approach is called A3 – defining a problem and goal for improvement, targeting candidate changes, and planning a series of tests to identify workable solutions. Lean has been most successfully used in organizations such as Virginia Mason Medical Center in Seattle, ThedaCare in Wisconsin, and the Pittsburgh Regional Health Initiative in Pennsylvania. The TPS template needs substantial alteration and customization in healthcare because several parties are responsible for prevention, patient care and payment, and patients themselves are also intrinsically ‘producers’ of their own outcomes.

QI per Deming emphasizes ‘Profound Knowledge’ among healthcare workers. Predictably successful improvement requires skills and knowledge across four domains: systems thinking, practical knowledge of what works, social factors in the work environment, and understanding variation. Shewhart’s principles guide execution – the foundational Plan-Do-Study-Act (PDSA) cycle for improvement work. The four basic steps in this cycle are planning a test of change and the intervention, implementing the intervention (Do), evaluating the results (Study), and acting based on the results (e.g., stay the course, abandon course, or make adjustments if necessary). Repeated PDSA cycles are needed for continuous quality improvement. Juran’s trilogy for quality management of macro processes consists of quality planning, quality control and quality improvement.

The white paper notes that both Lean and QI focus on systems, people, error proofing, reliability, repeated testing and experimentation to recognize problems and identify solutions, providing feedback and measuring outcomes. The key differences are 1. Lean focuses on value for the organization whereas QI methods focus additionally on population health and patient experience, 2. Lean methods are best when used for repetitive product production within a single enterprise with adaptation to clinical system while QI methods are best applied for spread of evidence-based practices across health care systems and coalitions of enterprises, 3. Lean methods emphasize standardization and reducing complexity whereas QI methods additionally allow changes to workflows for adoption, scale-up, and adaptation of support processes.

The paper concludes that Lean and QI methods are in no way contradictory to one another, and that they are in fact, complementary to each other. Both are needed in order to make ‘quality’ happen in healthcare. Per the authors, “This (the workplace or gemba per Lean) is where the “two jobs” of everyone in health care (per Maureen Bisognano) – to do the work and to improve how the work is done – come together.”