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
- Absorbing StateAbsorbing Health State, Absorbing Markov State
- A health state within a Markov model from which no further transitions are possible, most commonly death, once entered permanently.
C
- Cohort SimulationCohort-Level Simulation, Markov Cohort Run
- The process of running a Markov model by tracking the proportion of a hypothetical cohort in each health state over cycles, not individual patients.
- Cycle Length SelectionCycle-Length Choice, Time-Step Selection
- The methodological decision on how long each Markov model cycle should represent, balancing clinical precision against model complexity and available data.
- Cycle StructureModel Cycle Organisation, Temporal Model Structure
- The overall organisation of time within a Markov model, including the chosen cycle length and total number of cycles across the time horizon.
E
- Economic Model TypeModel Category, Decision-Analytic Structure
- The general category of decision-analytic structure, such as a decision tree, Markov model, or transmission model, chosen for a given evaluation.
H
- Health State DefinitionMarkov State Specification, State Clinical Definition
- The precise clinical specification of each distinct health state within a Markov model, describing the criteria a patient must meet to occupy it.
- Hidden Markov ModelHMM, Latent Markov Model
- A statistical model in which the true underlying state cannot be directly observed, only indicated indirectly and probabilistically by observable data.
- Horizon StructureModel Time Design, Cycle-Horizon Layout
- The way a decision-analytic model organises the passage of time, including cycle length in a Markov model or key evaluation points.
- Hybrid ModelHybrid Decision Model, Combined Model
- A decision-analytic model combining two or more approaches, such as a decision tree feeding into a Markov model, to represent a disease process.
I
- Integration TestingInterface Testing, Component-Interaction Testing
- A verification technique examining whether different model components, such as a decision tree feeding into a Markov model, work correctly together.
M
- Markov Cohort ModelCohort Markov Model, Aggregate Markov Model
- A Markov model tracking a hypothetical cohort collectively as proportions across health states over cycles, rather than simulating each patient separately.
- Markov MicrosimulationIndividual-Level Markov Model, First-Order Markov Simulation
- Markov microsimulation is an individual-level state-transition modeling method that simulates each person's sequence of health states over time using transition probabilities that may depend on current state, personal characteristics, time, and explicitly retained history.
- Markov ModelMarkov State Model, Multi-State Markov Framework
- A Markov model is a state-transition model in which a cohort or individuals move among mutually exclusive health states over repeated cycles, with future transitions determined by the current state under the model’s memory assumptions.
- Model IntegrationModel Coupling, System Integration
- The process of combining separate model components, such as a short-term decision tree and a longer-term Markov model, into one framework.
S
- State DefinitionState Characterisation, Health-State Description
- The precise specification of what constitutes a distinct health state within a Markov model, including the clinical criteria for assignment to it.
- State MembershipState Assignment, Cohort Allocation
- The specific health state a patient, or proportion of a modelled cohort, occupies at a given point within a Markov model.
- State OccupancyState Residence, Time in State
- The amount of time, typically in cycles, that a patient or cohort proportion spends within a given health state in a Markov model.
- State Transition DiagramMarkov Diagram, State Diagram
- A visual representation of a Markov model showing each health state as a labelled box and each permitted transition as an annotated arrow.
- State Transition ModelSTM, State-Transition Modelling
- A general term for a decision-analytic model, such as a Markov model, representing disease progression as movement between defined health states.
T
- Three-State ModelThree-Compartment Model, 3-State Markov Model
- A simplified Markov structure with exactly three health states, commonly well, diseased, and death, used when a fuller structure is unnecessary.
- Time StepSimulation Step, Iteration Interval
- The fixed interval of time by which a discrete-time model, such as a Markov model, advances with each calculation.
- Time StructureTemporal Structure, Model Timing Framework
- The way a model represents the passage of time, whether in fixed discrete cycles, as in a Markov model, or continuously.
- Time-Homogeneous ModelTime-Constant Model, Stationary Markov Model
- A Markov model in which transition probabilities remain constant throughout the entire modelled time horizon, regardless of how many cycles have passed.
- Time-Inhomogeneous ModelTime-Varying Markov Model, Non-Stationary Model
- A Markov model in which transition probabilities are allowed to vary over the time horizon, such as mortality risk rising with age.
- Trace ValidationTrace Checking, Patient-Path Checking
- The review of a Markov model's cohort trace, the proportion of a modelled population in each health state over time, for clinical plausibility.
- Transient StateNon-Absorbing State, Recurrent State
- A health state within a Markov model that a patient can leave and potentially return to, unlike an absorbing state such as death.
- Transition DefinitionTransition Rule, State-Change Criterion
- The precise specification of the clinical event or criteria triggering a patient's movement from one health state to another in a Markov model.
- Transition StructureAllowed-Move Pattern, State-Flow Structure
- The overall pattern of permitted movements between health states within a Markov model, reflecting which transitions are clinically plausible.
- Tunnel StateTemporary State Sequence, Tunnel Markov State
- A modelling technique creating temporary, time-specific states a patient passes through in sequence, letting a Markov model approximate time-dependent risk.