Accident: (1) A series of events that involves damage to a defined system disrupting the ongoing or future output of the system. (Kohn); (2) An unplanned, unexpected, and undesired event, usually with an adverse consequence. (Zipperer et al.)

Active error: An error that occurs at the level of the frontline operator and whose effects are felt almost immediately. (Kohn)

Active failure: (1) An error which is precipitated by the commission of errors and violations. These are difficult to anticipate and have an immediate adverse impact on safety by breaching, bypassing, or disabling existing defenses. (JCAHO 2001); (2) Errors and violations committed at the “sharp end” of the system — by pilots, air traffic controllers, police officers, insurance brokers, financial traders, ships crews, control room operators, maintenance personnel and the like. Such unsafe acts are likely to have a direct impact on the safety of the system and, because of the immediacy of their adverse effects, these acts are termed active failures. (Zipperer et al.)

Adverse event: (1) An injury that was caused by medical management (rather than the underlying disease) and that prolonged the hospitalization, produced a disability at the time of discharge, or both. (Brennan et al.); (2) An injury resulting from a medical intervention. (Kohn); (3) An untoward, undesirable, and usually unanticipated event, such as death of a patient, an employee, or a visitor in a health care organization. Incidents such as patient falls or improper administration of medications are also considered adverse events even if there is no permanent effect on the patient. (JCAHO 2001); (4) An event or omission arising during clinical care and causing physical or psychological injury to a patient. (NHS); (5) An injury that was caused by medical management and that results in measurable disability. (QuIC)

Adverse drug event (adverse drug error, ADE): Any incident in which the use of a medication (drug or biologic) at any dose, a medical device, or a special nutritional product (e.g., dietary supplement, infant formula, medical food) may have resulted in an adverse outcome in a patient. (JCAHO 2001); (2) An incident resulting from medical intervention related to a drug. (Zipperer et al.)

Adverse drug reaction (ADR): An undesirable response associated with use of a drug that either compromises therapeutic efficacy, enhances toxicity, or both. (JCAHO 2001)

Adverse sentinel event: An unexpected occurrence involving death or serious physical or psychological injury, or the risk thereof. Serious injury specifically includes the loss of limb or function. (JCAHO 1996)

Automation failure (Safety Concern): We should be able to react and respond to automation failures without compromising patients. Examples: equipment should be fail safe, or alarms should signal; work around plans should be available to recover from failures. (ESRD)

Bad outcome: Failure to achieve a desired outcome of care. (Kohn)

Benign errors: Events which cause no harm or lack an adverse outcome. Also referred to as precursor events or near misses. (Zipperer et al.)

Birth defects, miscarriage, stillbirth or birth with disease (Serious Adverse Reaction): If exposure to a medical product before conception or during pregnancy is suspected of causing an adverse outcome in the child. Examples: malformation in the child caused by the acne drug Accutane, or isotretinoin. (FDA)

Blunt end: …where regulatory, administrative, and organizational factors reside…The blunt end of the system is the source of the resources and constraint that form the environment where practitioners work. The blunt end is also the source of demands for production that sharp end practitioners must meet. (Zipperer et al.)

Classification system: The categorizing of errors into distinguishing levels based on their behavior, accountability, outcome, context, or process. (ESRD)

Cognitive science: An amalgamation of disciplines including artificial intelligence, neuroscience, philosophy, and psychology. Within cognitive science, cognitive psychology is an umbrella discipline for those interested in cognitive activities such as perception, learning, memory, language, concept formation, problem solving, and thinking. (Zipperer et al.)

Communication behaviors that increase risk to patients in operating theatres: Failure to inform team of patient’s problem (e.g., surgeon fails to inform anesthetist of use of drug before blood pressure is seriously affected) and failure to discuss alternative procedures. (Helmreich)

Communication breakdown related to treatment plan (Safety Concern): Discrepancies in communication of treatment plan between caregiver and patient, or between two caregivers. (ESRD)

Communications error: (from aviation) Missing or wrong information exchange or misinterpretation (e.g. misunderstood altitude clearance). (Helmreich)

Constraint and forcing strategies not available (Safety Concern): There were no checkpoints or required steps that would force individuals to recognize the pending mistake. Some activities can be engineered so that it is impossible to make a mistake (e.g., it is impossible to attach an oxygen connector to the suction outlet because the connector is designed to fit only the O2 outlet). (ESRD)

Complication: A detrimental patient condition that arises during the process of providing health care, regardless of the setting in which the care is provided. For instance, perforation, hemorrhage, bacteremia, and adverse reactions to medication (particularly in the elderly) are four complications of colonoscopy and its associated anesthesia and sedation. A complication may prolong an inpatient’s length of stay or lead to other undesirable outcomes. (JCAHO 2001)

Critical incident: A human error or equipment failure that could have lead (if not discovered or corrected in time) or did lead to an undesirable outcome, ranging from increased length of hospital stay to death. (Zipperer et al.)

Critical incident technique: A set of procedures for collecting direct observations of human behavior in such a sway as to facilitate their potential usefulness in solving practical problems and developing broad psychological principles. (Zipperer et al.)

Death (Serious Adverse Reaction): If an adverse reaction to a medical product is a suspected cause of a patient’s death. (FDA)

Decision error: (from aviation) decision that unnecessarily increases risk (e.g. unnecessary navigation through adverse weather). (Helmreich)

Disability (Serious Adverse Reaction): If the adverse reaction caused a significant or permanent change in a patient’s body function, physical activities, or quality of life. Examples: strokes or nervous system disorders brought on by drug therapy. (FDA)

Dose omission: The failure to administer an ordered dose to a patient before the next scheduled dose, if any. This excludes patients who refuse to take a medication or a decision not to administer. (NCC-MERP)

Environmental stressors (Safety Concern): Workload, workspace, staffing, time pressures, noise, heat. (ESRC)

Error: (1) Failure of a planned action to be completed as intended or use of a wrong plan to achieve an aim; the accumulation of errors results in accidents. (Kohn); (2) Failure to complete a planned action as intended, or the use of an incorrect plan of action to achieve a given aim. (NHS); (3) The failure of a planned action to be completed as intended or the use of a wrong plan to achieve an aim. Errors can include problems in practice, products, procedures, and systems. (QuIC)

Error in judgment: Error related to flawed reasoning. (Zipperer et al.)

Error of commission: An error which occurs as a result of an action taken. Examples include when a drug is administered at the wrong time, in the wrong dosage, or using the wrong route; surgeries performed on the wrong side of the body; and transfusion errors involving blood cross-matched for another patient. (JCAHO 2001)

Error of negligence: Error due to inattention or lack of obligatory effort. (Zipperer et al.)

Error of omission: An error which occurs as a result of an action not taken, for example, when a delay in performing an indicated cesarean section results in a fetal death, when a nurse omits a dose of a medication that should be administered, or when a patient suicide is associated with a lapse in carrying out frequent patient checks in a psychiatric unit. Errors of omission may or may not lead to adverse outcomes. (JCAHO 2001)

Error Severity Codes (ESRD):

1. Did not reach patient, potential injury: Examples: prescription bottle labeled correctly but nurse notices wrong pills in bottle, wrong medications loaded in Pyxis or med drawer, nursing station keeps all multidose medication vials in same the same drawer or bin. The patient has to tell lab tech not to take blood from a specific arm, no signs or notes on order or care plan, no sign in room.
2. Reached patient, no Injury or effect on patient: Examples: Missed antibiotics, double dose of pain meds, wrong lab tests done, wrong limb x-rayed, diagnostic test done incorrectly.
3. Emotional injury: Examples: Elopement or AMA, behavior health altercation between peers, wrongful confinement to a mental hospital, wrongful birth (birth after vasectomy, etc.), and fright, as well as 5th degree sexual conduct (touching or unacceptable sexual behavior, with no physical harm), use of restraints.
4. Minor Temporary: Minor patient injury or increased patient monitoring or change in treatment plan (with or without injury). Length of stay increased by less than 1 day. Examples: error in setting or monitoring heparin levels requiring increased number of lab tests, missed insulin dose requiring change in dosing for next administration and/or increased glucose checks. Bruising, abrasions, skin tear, complaints of pain, small number of non-facial sutures. Minor self- inflicted injury (scratches or cutting.)
5. Major Temporary: A temporary injury that exceeds minor temporary or increases length of stay one day or more. Examples: facial sutures, minor fractures, severe drug reaction.
6. Minor Permanent: A permanent injury that does not compromise basic functions of daily living. Examples: Loss of finger, loss of testicle or ovary, removal of bowel due to circulatory compromise, loss of teeth, 2nd degree sexual conduct (forced sexual contact via threat of violence or weapon, forced sexual contact that causes injury, or sexual contact with someone under 16 years old), retained sponge/needle.
7. Major Permanent: Permanent injury that affects basic functions of daily living. Examples: Hip fracture, nerve damage from improper surgical positioning, missing limb, damage to sensory organ, 1st degree sexual assault (forced sexual penetration via threat of violence or weapon, forced sexual penetration that causes injury, or sexual penetration of someone under 16 years old).
8. Extreme: Examples: Brain damage, severe paralysis, death.

Excessive handoffs (Safety Concern): Information transfers and task handoffs become more error prone each time a handoff occurs. Examples: change of shift issues, lunch breaks, ward secretaries performing order entry. (ESRD)