Human Error and Performance Variability
This lesson builds practical understanding of human factors engineering using a healthcare quality, patient safety, and high-reliability lens.
Learning outcomes
- Differentiate slips, lapses, mistakes, and violations.
- Explain performance variability without reducing events to individual blame.
- Recognize how work conditions shape human error risk.
Types of human error
Human performance failures are often grouped into slips, lapses, mistakes, and violations. Slips and lapses occur when the plan is sound but execution fails, such as selecting the wrong medication from a look-alike list. Mistakes happen when the plan itself is flawed. Violations involve deliberate deviation from expected practice.
Performance variability
People do not perform identically in every condition. Fatigue, interruptions, time pressure, ambiguous interfaces, alarm burden, noise, and workload all shape performance. Human factors engineering treats variability as normal and seeks to design systems that remain safe despite it.
Avoiding oversimplified blame
When a clinician makes an error, the visible act is often only the final point in a chain of system weaknesses. Similar packaging, hidden information, confusing screen design, inadequate staffing, or poor workflow may all contribute. Good analysis looks beneath the surface.
Designing for recovery
Strong systems do not assume people will never err. They build in checks, forcing functions, independent verification where needed, standardized communication, clear display logic, and recovery pathways that detect and correct error before harm reaches the patient.