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.
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.
A numerical method is a systematic computational procedure that approximates the solution of a mathematical problem through finite arithmetic operations, with accuracy assessed through error, convergence, stability, and conditioning.
Numerical optimisation uses iterative computational methods to find decision or parameter values that minimise or maximise an objective function.
Objective response rate (ORR) is the proportion of cancer trial patients with a complete or partial tumour response, an early efficacy measure in HTA.
Oblique rotation is a factor analysis step that lets rotated factors correlate, used when health domains such as physical and mental health are related.
One-way sensitivity analysis (OWSA) varies one model input at a time, holding the rest at base case, to show which inputs drive cost-effectiveness results.
Opportunity cost is the value of the best alternative given up when a resource is put to one use; in health care, usually health lost elsewhere.
A study sample size selected to meet a stated design objective, such as adequate power or precision, or to maximise the expected value of information after accounting for research costs and decision delays.
Ordinal utility is utility that records only how a person ranks options, such as two treatments, not how much one option is preferred to another.
An experimental design for a choice experiment in which attribute levels are varied independently, so each attribute's effect on preference can be separated statistically.
Orthogonal rotation is a factor analysis step that turns factor axes to simplify loadings while keeping factors uncorrelated, as in health questionnaires.
Overall survival (OS) is the time from randomisation or another set start to death from any cause, a final endpoint driving life-years and QALYs in HTA.
Overfitting is when a cost, risk or utility model fits chance noise in its development data, so it predicts worse for new patients than its fit suggests.
A p-value is the probability, if the null hypothesis and model held, of a result at least as extreme as observed, such as a trial cost or QALY difference.
Pairwise deletion is a missing data method that computes each correlation or covariance from all patients observed on both variables, so sample sizes vary.
The paradox of voting is a social choice problem in which majority votes on three or more health options cycle though each voter ranks them consistently.
A parameter distribution is a probability distribution describing uncertainty in the true value of a health economic model input, used in PSA.
Parameter estimation is the process of using evidence and a specified model or estimating rule to infer the values of quantities needed to describe a population, relationship, or decision model.
A parameter input (model parameter) is a value or distribution entered into a health economic model for a quantity such as a probability, cost or utility.
Parameter uncertainty is uncertainty in the estimated values of a health economic model's inputs, such as treatment effects, costs and utilities.
A statistical approach estimating a survival function by assuming the data follow a specific distribution, such as Weibull or log-normal, with estimated parameters.