Extended Dominance
Extended dominance excludes an option in cost-effectiveness analysis when a blend of a less and a more effective option gives its health gain for less.
Encyclopaedia
Explore comprehensive, evidence-informed explanations of key health economics concepts, including their development, application and relationships to other concepts. Published entries are validated through human expert review.
Concepts, entries and ontology terms
A concept page is a published entry on the wiki. Some concepts also have a full encyclopaedia article. The Health Economics Ontology (HEO) holds every concept, including dictionary terms without an article, so it is larger than the list of published pages. The knowledge graph shows how concepts relate to each other.
Externality
An externality is a cost or benefit, such as antimicrobial resistance or herd immunity, that falls on third parties and is ignored by the person deciding.
Extra-Welfarism
Extra-welfarism is a branch of welfare economics that judges health policies by outcomes such as health or capability, not by individual utility alone.
Extrapolation
Extrapolation is the projection of survival, treatment effects or costs beyond trial follow-up so an economic model can estimate lifetime outcomes.
F-Distribution
The F distribution describes the ratio of two independent variance estimates and underlies F tests on cost and outcome regressions in health economics.
Factor Analysis
Factor analysis explains correlations among observed variables using a smaller number of unobserved latent factors.
Factor Loading
A factor loading is a model-estimated coefficient that relates an observed variable to a latent factor under a specified factor-analytic measurement model.
Factor Rotation
Factor rotation transforms an extracted factor solution to make its loading pattern easier to interpret while preserving the model-implied common covariance under an equivalent transformation.
Fieller Method
The Fieller method calculates a confidence interval for a ratio such as the ICER, allowing for joint uncertainty in the cost and effect differences.
Finite Mixture Model
A finite mixture model treats data such as patient costs or utilities as coming from a fixed number of hidden subgroups, each with its own distribution.
First-Order Index
A first-order index in variance-based sensitivity analysis is the fraction of model-output variance explained by changes in the conditional mean when one uncertain input varies on its own under the specified input distribution.
Fixed Effects
Fixed effects are unit-specific terms in panel data regression that remove bias from stable unmeasured traits of patients, hospitals or areas.
Fleming-Harrington Estimator
The Fleming-Harrington estimator derives survival from censored trial data as the exponential of minus a cumulative hazard corrected for tied event times.
Fleming-Harrington Test
The Fleming-Harrington test is a weighted log-rank test whose two parameters tilt survival comparisons in trials and HTA towards early or late differences.
Flexible Parametric Model
A flexible parametric model is a survival model that uses splines in time to fit complex hazard shapes, giving smooth curves for extrapolation in HTA.
Folding Back
Folding back is the backward evaluation of a decision tree that takes probability-weighted values at chance nodes and selects the preferred feasible action at decision nodes under a stated objective.
Force of Infection
The force of infection is the rate at which a susceptible person acquires infection, the hazard driving dynamic models of vaccines and infection control.
Fractional Polynomial
A fractional polynomial is a regression function using one or two powers of a variable such as age or time to model curved effects on risk or survival.
Frailty Model
A frailty model is a survival model in which an unobserved random effect multiplies each patient's hazard to capture risk differences that covariates miss.
Frequentist Analysis
Frequentist analysis judges estimates, tests and confidence intervals by their behaviour over repeated samples, as in trial-based economic evaluation.