Quality improvement is a systematic, data-driven approach to making processes better over time. While the concept applies across many industries, it’s most commonly associated with healthcare, where it refers to structured efforts to improve patient outcomes, reduce errors, and eliminate waste. Rather than fixing problems after they cause harm, quality improvement works by continuously measuring performance, testing small changes, and scaling what works.
The Six Domains of Healthcare Quality
The most widely used framework for defining “quality” in healthcare comes from the Institute of Medicine, now adopted by the Agency for Healthcare Research and Quality. It breaks quality into six domains:
- Safe: Avoiding harm to patients from the care that is intended to help them.
- Effective: Providing services based on scientific knowledge to those who will benefit, while avoiding overuse for those who won’t.
- Patient-centered: Respecting individual preferences, needs, and values, and letting those values guide clinical decisions.
- Timely: Reducing waits and harmful delays for both patients and providers.
- Efficient: Avoiding waste of equipment, supplies, ideas, and energy.
- Equitable: Delivering care that doesn’t vary in quality based on a person’s location, income, or demographic characteristics.
These six domains give organizations a shared vocabulary for identifying where quality gaps exist. A hospital might score well on effectiveness but poorly on timeliness, for example, which points quality improvement efforts in a specific direction.
How Quality Improvement Differs From Quality Assurance
People often confuse quality improvement with quality assurance, but they work in fundamentally different ways. Quality assurance is reactive: it checks whether care met a defined standard, reviews individual cases with bad outcomes, and corrects problems after they happen. Quality improvement is proactive. It looks for opportunities to make systems better, uses statistical profiles as baselines, and measures progress against those baselines over time.
The cultural difference matters too. Quality assurance tends to make individual practitioners defensive because it focuses on identifying who made a mistake. Quality improvement shifts the lens to the system itself, asking what can be redesigned so that better care is the default. It builds on clinicians’ professional drive to provide better care tomorrow than they did today.
The Plan-Do-Study-Act Cycle
The most common method for running a quality improvement project is the PDSA cycle, a four-stage loop designed to test changes on a small scale before rolling them out widely.
In the Plan stage, you identify a specific goal and predict what will happen if you make a change. In the Do stage, you implement that change on a small scale, deliberately keeping the scope narrow so problems can surface quickly. The Study stage compares what you predicted to what actually happened, using data to assess the gap. Finally, the Act stage takes what you learned from the first three stages and refines the plan for the next round.
The key is repetition. Each cycle produces a slightly better version of the process. A team might run five or ten PDSA cycles before arriving at a change reliable enough to implement broadly. The Institute for Healthcare Improvement structures this approach around three guiding questions: What are we trying to accomplish? How will we know that a change is an improvement? And what change can we make that will result in improvement?
Lean and Six Sigma
Beyond PDSA, two other frameworks show up frequently in quality improvement work: Lean and Six Sigma. They solve different problems. Lean focuses on eliminating waste, whether that’s unnecessary steps in a process, idle equipment, or redundant paperwork. Six Sigma focuses on reducing variation, meaning it aims to make a process produce consistent, predictable results every time.
Many organizations combine them into Lean Six Sigma. The typical approach is to start with Lean’s qualitative tools to strip away waste, then apply Six Sigma’s statistical tools to reduce the remaining variation. In a hospital setting, this might mean first redesigning a discharge process to remove unnecessary steps (Lean), then analyzing why discharge times still vary from patient to patient and standardizing the remaining steps (Six Sigma).
How Improvement Gets Measured
Quality improvement relies on two main types of measures. Process measures track what providers are actually doing: the percentage of patients receiving recommended screenings, or the percentage of people with diabetes who had their blood sugar tested and controlled. These measures tell you whether a system is following best practices.
Outcome measures track the results: surgical mortality rates, hospital-acquired infection rates, or how often patients had complications. Outcome measures are what patients care about most, but process measures are often more useful for driving improvement because they point to specific steps that can be changed. If your infection rate is climbing, a process measure might reveal that hand hygiene compliance dropped, giving you a clear target.
Real-World Results
Quality improvement projects have produced dramatic results when well-executed. A children’s asthma program in Boston that combined one-on-one outreach nursing, patient education in self-management, and regular progress monitoring saw an 86 percent reduction in hospital admissions and a 79 percent decline in emergency department visits. Parkland Memorial Hospital in Dallas recorded a 53 percent reduction in asthma-related emergency visits within two years of launching an education and treatment program.
A VA facility in Memphis used a team-based approach to monitor patients and provide skin care, dropping its rate of pressure ulcer development from 11.5 percent to zero. LDS Hospital in Salt Lake City built a computerized system to track drug allergies, monitor kidney function during antibiotic treatment, and provide real-time feedback to physicians. The result was a 75 percent decline in adverse drug reactions related to antibiotics.
The financial case is equally clear. Brigham and Women’s Hospital spent $11.8 million over ten years developing and running a computerized physician order entry system. That system saved the hospital $28.5 million over the same period, roughly $2.2 million per year, through reduced drug costs, fewer unnecessary lab and radiology tests, and improved workflow. The system took more than five years to show a net benefit, which illustrates an important reality: quality improvement is a long-term investment.
Common Barriers to Implementation
Despite clear evidence that quality improvement works, many organizations struggle to sustain it. Research in primary care settings has identified several recurring obstacles. The most fundamental is time. Clinicians whose days are filled with patient appointments find it difficult to collect data, analyze it, and run improvement cycles. Quality improvement is additional work layered on top of already demanding schedules, and without dedicated time or staffing, projects stall.
Resource and staff shortages compound the problem. Many quality improvement projects end up simply trying to prevent quality from degrading rather than genuinely improving it, because teams are already stretched thin. When organizations assign new tasks and patient loads without adding resources, improvement work becomes what one study described as a “mission impossible.”
Cultural barriers matter just as much. When organizations focus their measurement and feedback systems on financial metrics like revenue and patient volume rather than clinical outcomes, staff don’t see quality improvement as relevant to their work. Professionals in one study reported that the dominance of non-clinical measures and external accountability requirements actually hindered their ability to focus on meaningful improvement. Lack of autonomy, where frontline staff have no say in choosing what to improve or how, further erodes engagement.
Current Federal Priorities
In the United States, quality improvement in healthcare is shaped partly by federal incentive programs. Under the Centers for Medicare and Medicaid Services Quality Payment Program, clinicians report on improvement activities in categories that reflect national priorities: achieving health equity, behavioral and mental health, beneficiary engagement, care coordination, emergency preparedness, expanded practice access, patient safety, and population management. Starting in 2025, these activities are no longer weighted differently. Clinicians simply need to complete one or two improvement activities depending on their reporting requirements, a simplification that lowers the administrative burden of participation.