PHER Key Words and Concepts

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Key Words and Concepts for Public Health and Patient Safety Draft 5.0 April 19, 2006 Dan Pollock

Note:

• Bold font is used in this draft for those terms and definitions that have been added or edited since publication of Draft 4.0, April 6, 2006. These are the most recent changes. They were made as a result of the discussion during the Public Health and Patient Safety Domain Analysis Model (DAM) conference call on April 7, 2006. Also included in bold font are patient safety terms and definitions submitted on April 13, 2006 by Peter Goldschmidt. Peter submitted these terms and definitions as personal recommendations and not as recommendations from the Agency for Healthcare Research and Quality (AHRQ). Decisions are needed about which of these terms are in scope for the DAM itself. Also, in some instances the terms Peter submitted are the same or similar to terms already used in this document (e.g., pharmacovigilance, outcome and health outcome), but with different definitions. For terms needed to support the DAM, definitional differences will need to be addressed through a reconciliation process.

1. Health system <Footnote 1> – A conceptual system (one that people form in their minds but does not exist in tangible form) that consists of components and their interrelationships that intend to maintain or improve people’s health. System components are: a. Public health programs – Efforts organized by society to protect, promote, and restore the health of a specified population or community through collective or social action. Public health programs tend to be managed by public sector organizations and emphasize disease and injury prevention and the health needs of the population as a whole. b. Personal health services – Delivery of health care to individuals by doctors, nurses, and other health care personnel working in the clinical sector – and by individuals themselves – and the organization, financing, and management of such care. c. Research and development – Generation of new knowledge, development of technology, assessment of existing and new health policies, practices, and programs, transfer of technology and dissemination of information, and development of methods and mechanisms for these purposes. d. Resource development – Provision of system inputs encompassing, for example, production of health care workers, construction of health facilities, health information technology development and support, and the approval, manufacture, and distribution of health care products. e. Policy management – Setting objectives and formulating policies for the health system, its components and their interrelationships; obtaining resources for the health system and allocating them among its components; monitoring system performance, including quality and safety of personal health services.

2. Health occurrences and case instances

1. Health problem – A disease instance or some other physical or psychological condition or event that adversely affects or could adversely affect the health of one or more persons or animals. A public health case is an observation about a health problem of concern to a public health program. Patient safety incidents include events in health care that did or could have resulted in a new health problem or exacerbation of an existing problem affecting one or more patients. Patient safety incidents may cause adverse effects other than health problems, such as breach of privacy or life-style or financial harm.
2. Public health event – A risk exposure or occurrence of a particular disease or another condition of concern to a public health program because of its impact or potential impact on one or more persons or animals. A public health event and a public health case are related but not synonymous. A public health event is a temporal occurrence that, in epidemiologic terms, is often conceptualized as an interaction or the result of an interaction between agent, host, and environment. A public health case is an observation about the host, i.e., person or animal, in the epidemiologic triad of agent-host environment.
3. Public health case – An observation that a person or animal in a population or community has a disease or another condition of concern to a public health program.
4. Public health exposure – Proximity or contact with a disease- or injury-causing agent, including an infected person or animal, or an environmental hazard.
5. Public health contact – A person who or animal that has been exposed to an infected person or animal or a contaminated environment in a way that did or may have led to transmission of an infectious disease of public health concern.
6. Outbreak – A significant increase in the incidence of a disease or some other condition of concern to a public health program above expected levels in a short period of time. An outbreak is comprised of a single case or multiple cases of a disease or some other condition.
7. Health care encounter – A single interaction, often over a short period of time, between an individual or group of associated individuals and one or more persons who deliver a health care service.
8. Medical procedure – A health care intervention, not part of routine medical history taking or physical examination, that is designed for prevention, diagnosis, or therapy.
9. Substance administration – Delivery of a medication, vaccine, or some other agent used for prevention, diagnosis, or treatment, regardless of whether the act of administration was intentional, inadvertent, or indeterminate with respect to intentionality.
10. Patient safety incident – A health risk, injury, or some other harm experienced or sustained by a person as a direct result of delivery of a personal health care service to that individual. These incidents include but are not limited to:
    1. Adverse drug event – An injury or other noxious effect due to medication use.
    2. Vaccine adverse event – An injury or other noxious effect due to vaccine use.
    3. Medical device-related adverse event – An injury or other noxious effect due to use or malfunction of equipment intended for prevention, diagnosis, or treatment.
    4. Healthcare associated infection ¬– An infection that occurs as a direct result of exposure to infectious agent during delivery of a personal health care service.
11. Health outcome – The result of an exposure to a disease- or injury-causing agent or a preventive or therapeutic intervention.

3. Public health activities

1. 1. Public health morbidity reporting – The process by which a health care provider or provider organization (including laboratories) conveys data to an agency with pertinent jurisdiction about a disease instance, laboratory result, or another condition of concern to a public health program in that agency.
2. Public health case notification – The process by which one public health agency conveys data to a second agency, often from one geopolitical level to another, about a disease instance or another condition of concern to public health programs in both agencies. This case notification process is typically triggered by a public health morbidity report.
3. Public health outbreak notification – The process by which one public health agency conveys data to a second agency, often from one geopolitical level to another, about an outbreak of concern to public health programs in both agencies.
4. Contact tracing – The process by which a public health program identifies and initiates follow up of a person who (or animal that) has been exposed to an infected person or animal or a contaminated environment in a way that did or may have led to transmission of an infectious disease of public health concern.
5. Public health investigation – The process by which a public health program inquires into an occurrence or circumstance of concern to it, such as an individual public health case, multiple cases, or one or more public health contacts, for purposes that may include identifying or verifying public health cases, at risk individuals, or causal, contributory, or mitigating factors.
6. Public health investigation request – The process by which one public health, public safety, or homeland security agency requests that a second agency, within a geopolitical jurisdiction or across jurisdictions, launch an inquiry into an event or circumstance of public health concern.
7. Public health case management – A set of functions and services provided by a public health case manager to prevent or control disease spread, including counseling, vaccination, antimicrobial administration, planning case follow up, determining exposure source and time, and contact tracing and documentation.
8. Public health outbreak management – A set of functions and services provided by an epidemiologist or other public health workers to prevent or control further spread of an outbreak, including determining outbreak extent, exposure source, and contact tracing performed during outbreak investigation.

4. Patient safety activities

1. 1. Patient safety incident reporting – The process by which a health care worker, patient, or some other responsible informant conveys data to an organization responsible for managing patient safety about a health risk, injury, or some other harm experienced or sustained by a person as a direct result of delivery of a personal health care service to that individual.
   2. Product-related risk or harm reporting to manufacturer – The process by which a doctor, nurse, or some other practitioner conveys data about a healthcare product-related risk or harm to the product\’s manufacturer.
   3. Pharmacovigilance – The science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug related problems, including pharmacoepidemiological studies. In this context the term "drug" denotes chemical entities, biotechnology-derived products, and vaccines.
   4. Root cause analysis – The process by which persons responsible for investigating a patient safety incident systematically identify, explore, and classify the basic or causal factors that underlie the incident.

Patient Safety Terms and Definitions Submitted by Peter Goldschmidt:

Accident — an undesired and unexpected event that usually has adverse consequences, and that may occur through an unplanned or unintended act; (in relation to patient safety) the term is best avoided as it carries the connotation that the adverse event occurred by chance or through "bad luck" and is thus inherently unavoidable.

Achievable benefit — the improvement in health status (compared to the natural history of a disease) that is possible to achieve for a patient of a given type from health care. Achievable benefit defines the limit of medical practice in being able to alter a patient\’s course for the better based on the effectiveness of specific preventive, diagnostic, and therapeutic interventions (treatments) and knowledge regarding their delivery, including the organization and financing of personal health services. Increasing achievable benefit requires research to develop more effective interventions, better ways of organizing and financing health care, etc.

Achievable benefit not achieved — that fraction of achievable benefit that was not achieved for a patient.

Adverse drug (medication) event — an adverse event involving a drug or medication.

Adverse event — an event that resulted in (residual) harm to a patient. Implicit in this idea is the fact that the harm can be measured in practice. Harm most often means loss or reduction in health status (including death or disability), but may also or instead include economic, social, or other loss or harm to a patient involved in the event.

Biological — a drug (biotechnologically-) derived from a living organism, including, without limitation, any virus, therapeutic serum, toxin, antitoxin, or analogous product of a plant or animal.

Blunder — something incorrectly done, especially through stupidity or clumsiness.

Close call — an event with the potential to harm a patient that almost occurred but did not occur, or such an event that did occur but in which harm was prevented from reaching the patient though the correct operation of a fail-safe, safeguard, etc.

Complication — (a second disease or) an injury or abnormal or detrimental patient condition occurring during the process of providing health care (for the primary disease). A complication may be the direct result of the disease\’s natural history, an inherent result of medical intervention or health care process, or result from an error in the provision of health care, or result from some combination of or the interactions among these factors.

Deviation — the act or instance of deviating (variance) from an established (standard) policy or procedure or accepted way of doing something. A deviation may be inadvertent (because a person was unaware of the established policy or procedure) or intentional (when a person knows, but willfully disregards, the established policy or procedure).

Drug (medication) — Any chemical compound (including biological and vaccine), not including food, that is intended to, or may, be used on or administered to a person (or, in the case of a veterinary drug, animal) as an aid in the prevention, diagnosis, or treatment of a disease, health problem, or other abnormal condition, or to enhance a person\’s (animal\’s) performance.

Error — a deviation; something incorrectly done, including a mistake, done through ignorance or carelessness; (in relation to patient safety) includes errors of commission and of omission.

Error of commission — an act done incorrectly, which may involve selecting the correct act and performing it incorrectly (an error of implementation, sometimes referred to as a slip, or, if it applies to a step in a procedure, as a lapse), or selecting the incorrect act for the circumstances (an error of planning, sometimes referred to as a mistake).

Error of omission — something done incorrectly because a required act was not done (in relation to patient safety), often one specified in a policy or procedure.

Event (or Incident) — an occurrence related to patient safety. This term encompasses relevant aspects of the following related concepts: accident, close call, complication, error, adverse event, near miss, no harm event, unsafe practice, and variance. An event may involve or relate to a drug, device, care process, etc, and may or may not involve an identifiable patient and/or result in (residual) harm to that patient.

Event cluster — individual events considered to be of the same type that occurred at different times, and may also have occurred in different places, that may be analyzed collectively, eg, to understand their root causes.

Event episode — a chain or series of events in which each subsequent event (link in the event chain) follows consequentially in space and time an initial index (or trigger) event and that results ultimately in a terminating event that may (but need not necessarily) produce a catastrophe. Analysis of the entire event episode is necessary to understand the root cause of the terminating, and consequences of the initiating, event.

Fail-safe — structure/process designed or intended to prevent the malfunction of a health care process that is usual an integral element of that process. A fail-safe is that aspect of the design of a health care process that triggers automatically an action or series of actions whenever a specified event or combination of events occurs in order to prevent potential harm to a patient. A fail-safe may or may not be triggered automatically when specified events occur, and, if triggered, may or may not be effective in avoiding (residual) harm to a patient.

Failure — the act, state, or fact of failing; a breakdown of operation or function, as may occur with respect to a medical device or health care process.

FME(C)A — Failure Modes, Effects, and (Criticality) Analysis (most often FMEA and FMECA), a problem solving technique that is most usefully applied when designing, but may be used when assessing, a health care process (usually one known or believed to represent a high-risk to patients\’ safety). The technique essentially consists of the following 8 steps: (1) define the system or process, including its elements and their interrelationships and the system\’s interrelationships other systems (delineating its boundaries), (2) identify failure modes for each element or sub-element or process involving interactions among (sub-)elements, (3) determine causes of failures, (4) assess failures\’ effects on the operation of the system, (5) classify severity of effects\’ of failures, (6) estimate the probability of effects\’ occurrence over a specified interval, (7) compute a criticality index (a quantitative measure that encompasses the product of multiplying severity by probability of occurrence, for each mode of failure of an element, etc), and (8) determine corrective actions, usually based on priorities established by the criticality index and severity classification. FMECA adds quantification (criticality) to FMEA. The term "reliability" is sometimes added, (R)FMECA, to indicate that the analysis pertain to the reliability of the system being analyzed. In relation to patient safety, the purpose of a FMECA is to identify how to (re)design care process or other actions that would reduce the risk of harm to patients.

Health care associated infection — an infection that occurred in a patient as a result of exposure to an infectious agent during the delivery of a personal health care service; such agent being exogenous to the patient, or, if endogenous, did not involve its transfer through medical intervention to a site that resulted in such an infection.

Health care (personal health services) — interventions intended to maintain or to improve individuals\’ health (status) delivered or administered by health workers, including the environment in which they are delivered; excluded specifically, for example, are harms from the lack of access to health care (for whatever reason) and self-care (except under the direction or supervision of a health care worker, and self-care incidents related to such regulated inputs as drugs and devices), and public health interventions such as broadcasts of public service announcements intended to motivate consumers to change their behavior.

Health status — an integrated measure of health (the health quality of live) that encompasses mortality, institutionalization, morbidity, ability to carry out activities, and, in principle, mental and emotional well-being, over a defined period, eg, (remaining) lifetime or 10 years after a treatment (or, in relation to patient safety, an event). This concept includes additional length of stay that resulted from an event as well as residual disability, emotional difficulties, etc.

Health worker — person paid or who volunteers to deliver health care (sometimes referred to as the "sharp end" of the delivery system), including a person who supervises him/her and/or assures the quality of his/her work, or who manages or is responsible for the built environment in which he/she works (sometimes referred to as the "blunt end" of the delivery system).

Lapse — a small or inconsequential error; (in relation to patient safety) overlooking or not performing a specified step in a procedure.

Latent error — an error that could potentially occur because of the design of a health care process, conditions under which it must be performed, or other circumstances. In contrast, an error that occurs is sometimes referred to as an "active error."

(Medical) device — any apparatus or other item that is not a drug that is intended to, or may, be used on or administered to a person (or, in the case of a vetinary drug, animal) as an aid in the prevention, diagnosis, or treatment of a disease, health problem, or other abnormal condition, or to enhance a person\’s (animal\’s) performance.

(Medical) device adverse event — an adverse event involving a device.

Medical mistake — mistake that occur in medical practice, or performing a personal health services or health care process.

Mistake — something that is wrong, or incorrectly understood, perceived, interpreted, done, etc, especially through ignorance or carelessness; (in relation to patient safety) often used to mean the selection of an incorrect act (regardless of whether or not it is performed correctly); see also error.

Multiple patient event — an event that involves two or more patients (eg, fire in a patient section of a hospital). Generally, the report would describe the event and the consequences for each patient involved in it.

Near miss — same as a close call.

No harm event — an event that either did not involve a patient (no named patient event) or did not harm the patient or patients (multiple patient event) involved. Reasons that an event involving a patient may not cause harm include good fortune, event did not lead to or trigger circumstances that resulted in harm, patient\’s fortitude (in being able to weather the consequences of the event without measurable harm), and/or timely (and effective) intervention of fail-safe, safeguard, and/or recovery, rescue, and/or rehabilitation action.

No named patient event — an event that does not involve a patient, (eg, discovery of an out of date batch of vaccine that was to have been administered to unknown or unnamed persons).

Nosocomial infection — an adverse event involving a health care associated infection.

Outcome — the result of a production process that precedes it in space-time acting on inputs in a given environment. In relation to health care, the term is often used to mean "patient outcome," and usually refers to post-process results or measurements (the observed results of an intervention) whether or not one can confidently attribute those results to the preceding process (intervention). Sometimes, the term is used to mean a result that can be confidently attributed to the preceding process, creating a potential source of confusion regarding attribution of effect or the effectiveness of the process (intervention).

Patient — a person receiving health care from a provider.

Patient safety — (in relation to the delivery of personal health services) a distinct subset of the quality of health care that pertains to the risk or occurrence of harm to a patient resulting from health care; excluded specifically are all other aspects of the quality of care, including achievable benefit from health care not achieved through omission or commission (including errors in and resulting from the design of care systems and processes and professional judgment), patient satisfaction with the inter-personal aspects of care, the efficiency of health care delivery, and trade-offs among various aspects of quality.

Patient safety event (incident) reporting — Reporting a (patient safety) event within the health care facility in which it occurred and/or to a regulatory agency, accrediting organization, or other external entity.

Pharmacovigilance — The science of and activities relating to the detection, assessment, understanding, and prevention of adverse effects (or any other drug-related problem). This definition includes such activities as conducting a pharmacoepidemiological study (and the resultant product of such activity), collecting or assembling post-approval (post-marketing) data sought systematically or reported spontaneously, and analyzing and evaluating such data to identify (an apparent excess of) adverse events pertaining to the use of a given drug or class of drugs.

Prescribed response (to an event) — the actions or series of actions, usually prescribed in policies and procedures, to be taken when a specified event or combination of events occurs (in connection with patient safety) when a malfunction occurs in a health care process.

Preventable event — an event the occurrence of which can be prevented or avoided according to existing knowledge or the prevailing believes of appropriately qualified experts. This idea implies that the adverse event that occurred was predicable and could have been prevented by the application of some means currently available that is appropriate for the circumstances but it was not applied; thus such omission constitutes an error of design, implementation, training, etc.

Process — a particular method of doing something (in relation to patient safety, to delivery of a personal health service), generally involving a number of steps or operations, that results in an outcome or produces an output.

Product related event (incident) reporting (to manufacturer) — Reporting an adverse event involving a drug or device event to its manufacturer, usually to meet a regulatory requirement.

Provider — institution, facility, or organization (eg, ambulance/first response service, ambulatory surgery center, clinic, group practice, health maintenance organization, hospital, nursing home) that, or individual (physician or other health care practitioner) who, delivers health care services, or that supports the deliver of such services (eg, blood or tissue bank, imaging center, laboratory), to individual patients.

Recovery action — (in relation to patient safety) an action or series of actions specified in a prescribed response or taken spontaneously (including overriding a prescribed response), after the recognition of an error or event (maloccurence in a health care process or the environment in which it occurred), that is intended to prevent maloutcome (harm to a patient) as a result of the malfunctioning of a care process, or fail-safe or safeguard.

Rehabilitation action — (in relation to patient safety) action taken after failure of rescue to restore a patient to prior condition.

Reporting — giving a verbal or written account of an event or incident, including, without limitation, a description of what occurred, circumstances of its occurrence, etc, and what, if anything, was done subsequently and/or happened as a result.

Rescue action — (in relation to patient safety) an action or series of actions specified in a prescribed response or taken spontaneously after an adverse event has occurred to a patient that is intended to minimize residual harm to that patient.

Residual harm — (in relation to patient safety) the reduction in a patient\’s health status (or other significant outcome) that exists as a result of an adverse event, often after the mitigating effects of a recovery, rescue, and/or rehabilitation action.

Risk — the potential harm that may result from a present process or future event. This concept combines the probability that something occurs in a specified interval with the occurrence\’s negative consequences. Statistically, risk may be expressed as variance from expected results (mean) without reference to its consequences. Often, the term risk is synonymous with the probability of the occurrence of an event, such as the chance that a disease will be observed in an individual in a given population. Generally, risk refers to the probability that a specified outcome will occur; uncertainty, to the view that the outcomes of a system or process that may eventuate are unknown or unknowable.

Root cause — the cause at the root of an effect or event. A root cause may lie in the design of or performance relating to a health care process (including human factors), the input to such process (including a drug or device), the environment in which it operates (including organizational factors), or the culture (including social factors). Operationally, a root cause is a factor of production that can be controlled or moderated by the organization that is responsible for the design of and performance relating to the health care process that gave rise to the event being analyzed.

Root cause analysis — a problem solving technique (which usually involves systematic analysis and assembly of evidence) that is intended to identify or discover the root cause or combination of causes that produced an event, event cluster, or event episode, especially when the purpose in using the technique is to reduce the chance of recurrence of the event.

Rule — an authoritative regulation for action, conduct, or use of a specified method, etc such as policy and/or procedure that has been established by an authoritative body, such as a quality management department or government.

Sabotage — intentional destruction of machines, waste of materials, etc, often by employees; (in relation to patient safety) an act intended to harm, or to create a condition intended to result in harm to, a patient.

Safeguard — structure/process designed to prevent maloutcome (harm to a patient from health care) from malfunction (error in the design, implementation, or performance) of a health care process or the environment in which it operates. A safeguard is that aspect of a health care process that is designed or intended to prevent potential harm from reaching a patient in the event of a malfunction of a health care process. A safeguard may or may not be triggered by a malfunction, and, if triggered, may or may not be effective in avoiding (residual) harm to a patient.

Slip — an inadvertent mistake; (in relation to patient safety), often used to mean unintended error in implementing a correctly selected (and hence intended) act, especially one resulting from lack of or inadequate skill.

Structure — (in relation to patient safety) is the physical and/or organizational framework (system elements) in which a health care process occurs. In this sense, sometimes expressed as "structure/process" or simply "process" (with structure being understood as a necessary framework). In relation to the quality of health care (and sometimes patient safety), structure (structural variables) are (or also encompass) inputs to processes, such as providers\’ qualifications, drugs or deices, etc.

Unsafe (work) practice — a structure or process (including inputs), or their environment, that poses a known risk of harm to patients, regardless of whether or not a patient has yet been harmed. Hence, the structure, process (or input), or their environment, may be termed to be defective or deficient.

Vaccine — a suspension of an attenuated (weakened) or killed microorganism such as a bacterium or virus administered for prevention, amelioration, or treatment of infectious disease.

Vaccine adverse event — an adverse event involving a vaccine.

Variance — (in relation to patient safety) a deviation.

Violation — a deviation determined by an authoritative, usually, regulatory, body, such as a quality management department, government agency, committee of inquiry, etc, usually involving a rule. Notes

1. The terms and definitions for health system and its components are adapted from Lionel Wilson, Peter Goldschmidt Quality Management in Healthcare. Roseville, Australia: McGraw-Hill Book Company, Australia, 1995.