Chance Node
A chance node is a point in a decision tree where an uncertain event, not a choice, decides the pathway, and its branch probabilities sum to one.
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.
Chi-Square Distribution
The chi-square distribution describes a sum of squared independent standard normals and is the reference for likelihood ratio, heterogeneity and fit tests.
Choice Architecture Intervention
A choice architecture intervention changes how health options are set out, such as defaults, order or placement, to shift choices without removing options.
Choice Experiment Design
Choice experiment design is the plan of attributes, levels and choice tasks in a DCE, which fixes the health preference effects that can be estimated.
Choice Model Estimate
Choice model estimate is a preference weight, or a derived value such as willingness to pay, from a choice model fitted to stated or revealed choices.
Choice Overload
Choice overload is the effect in which a large or complex set of options can lead people to defer a choice or regret it, as in health insurance markets.
Choice Set
The group of alternatives, typically hypothetical options and sometimes a status quo, presented to a respondent in a single choice task.
Choice Theory
Choice theory is the economic theory of how people choose among options given preferences and limited resources, underpinning demand and health valuation.
Choice-Based Conjoint
Choice-based conjoint (CBC) is conjoint analysis in which patients or others choose between sets of described treatments or services rather than rate them.
Cholesky Decomposition
Cholesky decomposition factorises a positive-definite covariance matrix into a triangular matrix and its transpose, used to sample correlated PSA inputs.
Classification Accuracy
Classification accuracy is the proportion of cases a test, coder or prediction rule assigns to the correct category, judged against a reference standard.
Classification Methods
Classification methods are statistical and machine learning techniques that assign patients or other cases to predefined classes, such as risk groups.
Clawback
Clawback is a payment that medicine manufacturers return to a payer when total public spending on medicines exceeds an agreed cap.
Clinical Benefit Rate
Clinical benefit rate (CBR) is the share of cancer trial patients with a complete or partial response, or stable disease lasting a set minimum time.
Clinical Decision Analysis
Clinical decision analysis is a method for choosing a patient's test or treatment by combining outcome probabilities and utilities in a decision tree.
Clinical Development Plan
A clinical development plan is a sponsor's ordered programme of clinical trials, with decision points, to support marketing approval and often HTA.
Clinical Plausibility
Clinical plausibility is the extent to which a health economic model's structure, inputs and results agree with clinical knowledge of the disease.
Clinical Trial Design
Clinical trial design is the protocol plan for a trial's comparator, population, endpoints, follow-up and sample size, setting how far results inform HTA.
Closed-Form Analytical Method
A closed-form analytical method solves a health economic model with a formula, such as a matrix inverse, instead of by simulation or random sampling.
Club Goods
Club goods are excludable goods a group can share without rivalry until congestion sets in, so users can be charged and membership limited.