Dictionary
The Dictionary provides concise definitions of health economics terms, arranged alphabetically for quick reference. Use it to understand unfamiliar terminology or confirm the meaning of a specific term.
A
- Absolute Risk ReductionARR, Absolute Benefit Increase
- Absolute risk reduction is the arithmetic difference in the probability of a specified adverse outcome between a comparator group and an intervention group over the same defined time horizon.
- Active ComparatorActive Control, Active Reference
- The existing treatment or standard of care against which a new intervention is compared in an economic evaluation.
- Active TreatmentInvestigational Treatment, Active Arm Treatment
- The intervention under investigation in a trial intended to have a genuine pharmacological or therapeutic effect, unlike a placebo or inactive comparator.
- Average Analysis MethodAverage Approach, Total-to-Total Analysis
- An analytic approach comparing an intervention's total cost to its total effect independently, rather than incrementally against a specific comparator.
- Average Treatment EffectATE, Population Average Effect
- The mean difference in outcomes that would occur if every member of a population received a treatment versus a comparator instead.
B
- Baseline RiskBaseline Event Rate, Untreated Risk
- The probability of a clinical event occurring without the intervention being studied, typically estimated from a trial's comparator arm or observational data.
- Basket of CountriesCountry Basket, Comparator Basket
- The specific set of countries whose prices serve as the comparison reference when a country sets its own drug prices.
- Benefit AssessmentClinical Benefit Evaluation, Added Benefit Evaluation
- A formal evaluation of the clinical benefit a treatment provides relative to an appropriate comparator, used to inform reimbursement and pricing decisions.
- Best Available TreatmentBAT, Best Available Therapy
- The most effective treatment currently accessible for a condition, used as the comparator against which a new intervention's incremental value is assessed.
C
- Cancer Treatment EconomicsOncology Treatment Economics, Cancer Therapy Economics
- The analysis of costs, health outcomes and resource consequences across cancer treatment pathways for a specified population, comparator, perspective and decision.
- Clinical BenefitTherapeutic Benefit, Patient Benefit
- A favourable effect of an intervention on how a patient feels, functions or survives relative to an appropriate comparator.
- Clinical Guideline HTAGuideline Role in HTA, Guideline HTA Context
- The specific role of clinical guidelines within the assessment process, providing context on standard of care and comparator selection.
- Clinical Trial DesignRCT Design, Protocol Design
- The structural and methodological plan for a trial, covering randomisation, comparator choice, and endpoint definition, shaping the evidence's suitability for economic modelling.
- Common ComparatorShared Comparator, Common Reference Treatment
- A treatment directly compared against two or more other treatments in separate trials, providing the link needed for an indirect comparison.
- ComparatorControl Intervention, Reference Arm
- The alternative intervention, treatment, or strategy against which a new option is evaluated in an economic evaluation.
- Comparator SelectionComparator Choice, Choice of Comparator
- The process of identifying the appropriate existing treatment against which a new technology will be evaluated within an economic evaluation.
- Comparator StructureComparator Set, Model Comparator Arms
- The specific set of alternative interventions included in a decision-analytic model against which the intervention of interest is evaluated.
- Control ArmTrial Control Group, Comparison Arm
- The trial group receiving a comparator treatment, such as a placebo or standard of care, against which the experimental intervention is compared.
- Cost per QALYCost/QALY, Cost per Quality-Adjusted Life Year
- A measure of value for money in cost-utility analysis, calculated as incremental cost divided by the quality-adjusted life years gained relative to a comparator.
- Cost-Effective InterventionGood-Value Intervention, Efficient Intervention
- An intervention whose additional cost relative to its comparator is acceptable given its additional health benefit, judged against a cost-effectiveness threshold.
- Cost-Effectiveness PlaneCE Plane, Incremental Cost-Effect Plane
- A graph plotting an intervention's incremental cost against its incremental effect relative to a comparator, cost on the vertical axis and effect on the horizontal.
E
- Effect SizeMagnitude of Effect, Standardised Effect
- An effect size is a measure of the magnitude of an association or intervention effect for a specified outcome, comparator, population, and scale.
- EffectivenessReal-World Benefit, Routine-Practice Benefit
- The benefits and harms an intervention produces under care conditions relevant to a specified population, comparator, outcome and time horizon.
- External Control ArmRegistry Control Group, Synthetic Control Arm
- A comparator group built from data outside the trial itself, such as a historical cohort or registry, used when no concurrent control is feasible.
H
- Head-to-Head ComparisonDirect Comparison, Direct Head-to-Head Trial
- A trial directly comparing two or more active treatments against one another within the same study, rather than each against a separate common comparator.
- HTA ScopeAssessment Scope, Scope Definition
- The formally defined boundaries of an assessment, specifying the technology, population, comparators, and outcomes to be considered.
I
- Incremental CostAdditional Cost, Marginal Cost Difference
- Incremental cost is the difference in expected total cost between one healthcare option and its stated comparator, calculated using the same population, perspective, time horizon, currency, price year and costing methods.
- Incremental EffectivenessAdditional Effectiveness, Incremental Health Gain
- Incremental effectiveness is the difference in health outcomes between an intervention and its comparator, calculated in a consistent outcome unit and comparison direction.
- Indirect ComparisonAnchored Comparison, Bucher Method, Indirect Treatment Comparison, ITC
- A method estimating the relative effect of two treatments never studied against each other directly, using their separate effects versus a shared comparator.
- Indirect EvidenceIndirect 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.
- Indirectness
- A GRADE evidence quality domain assessing whether the population, intervention, comparator, or outcome studied differs meaningfully from those relevant to the actual decision.
L
- Local Value DossierCountry Value Dossier, Local Payer Dossier
- A country-specific document adapting a global health economic evidence package to a national health technology assessment body's requirements and comparators.
M
- Methodological QualityStudy Quality, Methodological Rigour
- An overall assessment of whether a model or study followed accepted good practice standards, covering comparator choice, time horizon, and reporting transparency.
N
- Natural History StudyUntreated Disease Study, Disease Course Study
- A study observing a disease's course over time without an experimental treatment, providing baseline information used as an external comparator, particularly for rare diseases.
- Network Meta-AnalysisNMA, Multiple-Treatments Meta-Analysis, Mixed Treatment Comparison, MTC
- Network meta-analysis, or NMA, compares three or more interventions by combining direct evidence from head-to-head studies with indirect evidence connected through common comparators.
- Non-Inferiority TrialNI Trial, Non-Inferiority Study
- A trial designed to show a new treatment is not meaningfully worse than an active comparator, within a predefined acceptable margin.
- Northeast QuadrantNE Quadrant, More Costly More Effective Quadrant
- The region of the cost-effectiveness plane where a new intervention is both more costly and more effective than its comparator.
- Northwest QuadrantNW Quadrant, Dominated Quadrant
- The region of the cost-effectiveness plane where a new intervention is both more costly and less effective than its comparator.
- Number Needed to TreatNNT, Treatment Number Needed
- The reciprocal of a nonzero absolute difference in event risk between an intervention and comparator, interpreted as the expected number treated for one additional beneficial or harmful outcome over a stated period.
P
- PICO FrameworkPICO, Population-Intervention-Comparator-Outcome
- A structured framework specifying the Population, Intervention, Comparator, and Outcome, used to formulate a well-defined clinical or research question.
- Placebo ComparatorPlacebo Control, Inactive Comparator
- A comparator representing no active treatment, used when no established active treatment exists or the question concerns treatment versus no intervention.
- Price PremiumPricing Premium, Value Premium
- The additional amount a manufacturer charges for a treatment relative to an existing comparator, reflecting the treatment's demonstrated incremental clinical benefit.
Q
- QALY GainIncremental QALY, QALYs Gained
- The increase in quality-adjusted life years attributable to an intervention, the difference between the QALYs expected under it and its comparator.
R
- Randomised Controlled TrialRCT, Randomised Trial
- A trial design in which participants are randomly assigned to an experimental intervention or a comparator, the gold standard for causal evidence.
- Reference BasketPrice Comparator Set, Reference Country Group
- The specific group of countries whose drug prices are used as the reference point when a country sets its own prices.
- Reference CountryComparator Country, Benchmark Country
- A specific country whose drug prices are used as a comparison point when another country sets or negotiates its own prices.
- Reference Country SelectionComparator Country Choice, Basket Country Selection
- The process of choosing which countries are included in the reference basket used to set or negotiate a drug's price.
- Reference PricingBenchmark Pricing, Comparator-Based Pricing
- A pricing policy setting a benchmark price based on prices of similar products or the same product elsewhere, constraining pharmaceutical spending.
S
- ScopingScoping Phase, Scope Definition
- The initial assessment stage in which the specific boundaries, including technology, population, comparators, and outcomes, are formally defined.
- Synthetic ControlSynthetic Comparator, Data-Derived Control
- A quasi-experimental method constructing a weighted combination of untreated units to serve as a comparison group resembling a treated unit before intervention.