Dictionary

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Incremental InnovationTerm

An innovation making gradual, often modest improvements to an existing product or technology, unlike a radical or disruptive innovation.

Incremental Net BenefitConceptINB, Incremental Net-Benefit Statistic

The difference in expected net benefit between two competing interventions, found by converting the incremental health effect into money and subtracting incremental cost.

Incremental Net Monetary BenefitConceptINMB, Incremental Monetary Net Benefit

Incremental net monetary benefit (INMB) is the extra health of an option over its comparator, valued at a threshold, minus the extra cost, per patient.

Incubation PeriodTermIncubation Time, Exposure-to-Symptom Interval

The time interval between exposure to an infectious agent and the onset of symptomatic disease in an infected person.

IND ApplicationTermInvestigational New Drug Application, IND

An Investigational New Drug application requesting permission to begin human clinical trials, containing preclinical safety data and a proposed trial plan.

Independent AssessmentTermIndependent Evaluation, Arms-Length Assessment

An assessment conducted by an evaluator without a direct financial interest in the outcome, unlike one funded by the manufacturer.

Independent CensoringConceptNon-Informative Censoring, Random Censoring

An assumption that, within the information used for a survival analysis, censoring does not convey additional information about a person’s unobserved event time.

Independent Practice AssociationTermIPA, Independent Physician Association

An organisation of independent physicians contracting collectively with managed care organisations while maintaining their own separate practices.

Index InstrumentTermIndex-Based Measure

A health status questionnaire combining responses across dimensions into a single summary utility score, unlike a profile instrument reporting each dimension separately.

IndicationTermApproved Use, Licensed Use

The specific medical condition or use for which a drug has received regulatory approval and is intended to be prescribed.

Indication-Based PricingTerm

A pricing approach in which a single drug is priced differently depending on the medical condition, or indication, for which it is used.

Indicator DevelopmentTermMetric Development, Measure Development

The process of designing and validating a specific, measurable metric intended to capture a dimension of healthcare quality or outcome.

Indirect BenefitTermSocietal Research Benefit, Non-Personal Benefit

A potential positive outcome resulting from a study that does not directly benefit the individual participant, such as knowledge helping future patients.

Indirect ComparisonConceptAnchored Comparison, Bucher Method

A method estimating the relative effect of two treatments never studied against each other directly, using their separate effects versus a shared comparator.

Indirect CostTerm

A cost associated with an intervention that is not directly incurred in providing it, such as lost productivity from illness or premature death.

Indirect EvidenceTermIndirect NMA Evidence, Chained Evidence

Within network meta-analysis, evidence comparing two treatments derived through a chain of comparisons via a common comparator, not from direct trials.

Indirect Treatment ComparisonConceptITC

Indirect treatment comparison (ITC) is the umbrella term for methods, such as NMA or MAIC, that compare treatments no trial has tested head to head.

Indirect Utility AssessmentConceptIndirect Elicitation

The process of obtaining a health state utility value by applying a scoring algorithm from a prior valuation study to a respondent's questionnaire answers.

IndirectnessTerm

A GRADE evidence quality domain assessing whether the population, intervention, comparator, or outcome studied differs meaningfully from those relevant to the actual decision.

Individual Funding RequestTermIFR, Individual Patient Funding Request

A formal clinician application requesting funding for a patient's treatment outside standard coverage, demonstrating genuinely exceptional circumstances.

Individual MandateTerm

A legal requirement that individuals maintain a minimum level of insurance coverage or face a financial penalty, to prevent adverse selection.

Individual MarketTerm

The insurance market segment where coverage is purchased directly by individual consumers rather than through an employer or other group.

Individual Patient Data Meta-AnalysisConceptIPD Meta-Analysis, IPD-MA, Individual Participant Data Meta-Analysis, Participant-Level Meta-Analysis, Patient-Level Meta-Analysis, Individual Patient Meta-Analysis

Individual patient data meta-analysis systematically obtains, checks, and jointly synthesises participant-level records from eligible studies to estimate effects and investigate variation across studies or patients.

Individual Patient SimulationConceptIPS, Patient-Level Simulation, Individual-Level Simulation, Microsimulation, Patient-Level Microsimulation, Individual-Based Simulation, Individual Patient Modelling, Individual Patient Modeling

Individual patient simulation is a modelling approach that generates separate patient histories under specified rules and aggregates their costs and health outcomes for a target population.

Individual-Level ModelTerm

A decision-analytic model tracking simulated patients one at a time rather than representing a population using aggregate cohort proportions.

Induced InnovationTermInsurance-Driven Innovation, Cost-Shielded Innovation

The theory that health insurance, by shielding patients from full costs, steers medical innovation toward more expensive, quality-enhancing treatments rather than cost-reducing ones.

Induction TherapyTermInduction Regimen, Initial Intensive Therapy

An initial, often intensive treatment given to rapidly reduce disease burden at the start of a course, typically followed by consolidation or maintenance.

Industry RepresentativeTermManufacturer Representative, Industry Stakeholder, Industry HTA Liaison

An individual employed by or contracted to a manufacturer who provides input or represents its perspective during an assessment process.

Inelastic DemandConceptPrice-Insensitive Demand, Unresponsive Demand

A condition in which quantity demanded changes proportionally less than a given price change, indicating consumers are relatively insensitive to price.

Inequality IndexTermInequality Measure, Distributional Index

A summary statistic that quantifies the extent of inequality in the distribution of income or health across a population, allowing comparison over time or between groups.

Infection MeasureTermInfection Indicator, HAI Measure

A quality indicator tracking the frequency of specific healthcare-associated infections, such as central line-associated bloodstream infections, within a facility.

Infection RateTermInfection Frequency, Infection Occurrence Rate

A measure of how frequently a specific type of infection occurs within a defined population and time period.

Infectious Disease EconomicsTermEconomics of Infectious Disease, Communicable Disease Economics, Fungal Infection Economics, Mycosis Economics, Fungal Disease Economics, Hepatitis Economics, Liver Inflammation Economics, Viral Liver Disease Economics, Parasitic Disease Economics, Parasite Disease Economics, Parasitology Economics, Healthcare Infection Economics, Nosocomial Infection Economics, HAI Economics, Infection Control Economics, Economics of Infection Control, IPC Economics, Pandemic Preparedness Economics, Preparedness Economics, Pandemic Readiness Economics, Respiratory Infection Economics, RTI Economics, Respiratory-Infection Cost

The broad application of health economic evaluation to the prevention, diagnosis, and treatment of diseases caused by pathogenic microorganisms.

Infectious Disease EpidemiologyTermCommunicable Disease Epidemiology, ID Epidemiology

A branch of epidemiology studying the distribution, transmission dynamics, and control of communicable diseases within populations.

Inferential StatisticsTermStatistical Inference, Inferential Methods

A branch of statistics drawing conclusions about a broader population from sample data, incorporating formal methods for quantifying uncertainty.

Inflammatory Bowel DiseaseTermIBD, Crohn's and Colitis

A group of chronic conditions, mainly Crohn's disease and ulcerative colitis, involving digestive tract inflammation with a relapsing, remitting course.

Inflation AdjustmentTermPrice Rebasing, Real-Terms Adjustment

The process of restating cost data from different time periods in constant, comparable price terms, typically using a relevant price index.

Inflation RateTermRate of Inflation, Price Inflation

The percentage rate at which the general level of prices for goods and services rises over a given period.

Influential ObservationTermInfluential Point, High-Influence Observation

A data point that, if removed, would substantially change a statistical analysis's results, such as a regression model's estimated coefficients.

Informal Care CostTermUnpaid Care Cost, Informal Caregiving Cost

The economic value of unpaid caregiving time from family or friends, typically estimated using replacement cost or the carer's forgone time.

Information AsymmetryConceptAsymmetric Information, Information Imbalance

Information asymmetry occurs when one party to an economic decision has more or better information than another, affecting choices, bargaining power and the efficiency of resulting outcomes.

Information BarrierTermAwareness Barrier, Information Access Obstacle, Knowledge Barrier, Understanding Gap, Comprehension Barrier

An obstacle to healthcare arising from a lack of adequate information, whether about available services, one's condition, or the system.

Information BiasConceptObservation Bias, Ascertainment Bias, Measurement Bias

A category of bias from errors in how exposure, outcome, or covariate data are measured or recorded, including recall bias and measurement error.

Information EconomicsTermEconomics of Information, Info Economics

The branch of economic theory examining how the distribution of information among market participants affects outcomes, including adverse selection and moral hazard.

Informed ChoiceConcept

Informed choice is a decision about a screening test or treatment based on relevant knowledge, consistent with the decision maker's values and acted upon.

Informed ConsentTermVoluntary Consent, Consent to Participate

The process by which a potential participant is given enough information about a study to make a voluntary, informed decision to join.

Informed Consent for ResearchConceptResearch Participation Consent, Study Consent Process

A voluntary, informed and ongoing agreement to participate in specified research after an understandable explanation and opportunity to decide freely.

Informed RefusalTermTreatment Refusal, Informed Declination

A patient's decision to decline recommended treatment after being given sufficient information about its risks, benefits, and alternatives.

Infusion CentreTermInfusion Clinic, IV Therapy Centre

A specialist facility dedicated to administering intravenous medications, such as chemotherapy or biologic infusions, typically on an outpatient basis.

InhalationTermInhaled Administration, Respiratory Route

A route of drug administration delivering medication directly to the lungs through breathing, commonly used for asthma and chronic obstructive pulmonary disease.