Diagnostic error has been increasingly recognized as an important and evolving patient safety issue. This Primer applies well-established principles of diagnostic error and improvement of diagnostic accuracy to the topic of COVID-19.

Nurses play a critical role in patient safety through their constant presence at the patient's bedside. However, staffing issues and suboptimal working conditions can impede a nurse’s ability to detect and prevent adverse events.

Discharge planning is an essential part of transitions of care, during which patients are often at a higher risk for adverse events and harm. It is important for all healthcare providers to identify risk factors prior to transitioning patients and put plans in place as part of the discharge plan to mitigate harm. Effective discharge planning between the discharging and accepting healthcare teams can help reduce adverse events.

Infections after surgery are common and frequently lead to hospital readmission and other adverse consequences for patients. Recent programs, including several led by the Agency for Healthcare Research and Quality, have demonstrated how hospitals can successfully prevent these infections.

This Primer provides an overview of the history and current status of the patient safety field and key definitions and concepts. It links to other Patient Safety Primers that discuss the concepts in more detail.

Few medical errors are as terrifying as those that involve patients who have undergone surgery on the wrong body part, undergone the incorrect procedure, or had a procedure intended for another patient. These "wrong-site, wrong-procedure, wrong-patient errors" (WSPEs) are rightly termed never events.

Thousands of patients die every year due to diagnostic errors. While clinicians’ cognitive biases play a role in many diagnostic errors, underlying health care system problems also contribute to missed and delayed diagnoses.

Discontinuity is an unfortunate but necessary reality of hospital care. No provider can stay in the hospital around the clock, creating the potential for errors when clinical information is transmitted incompletely or incorrectly between clinicians.

Being discharged from the hospital can be dangerous for patients. Nearly 20% of patients experience an adverse event in the first 3 weeks after discharge, including medication errors, health care–associated infections, and procedural complications.

The list of never events has expanded over time to include adverse events that are unambiguous, serious, and usually preventable. While most are rare, when never events occur, they are devastating to patients and indicate serious underlying organizational safety problems.