Topic

Model types and structures (general)

The broad choices that shape any health economic model, such as whether it is deterministic or stochastic and whether time moves in discrete steps or continuously. Concepts such as time dependency and assumption structure describe how a model represents disease progression and treatment effects before a particular model type is chosen.

Concepts in this topic

• Assumption StructureAssumption structure is the full set of simplifying assumptions in a health economic model's design, such as its health states, events and extrapolation.
• Continuous ModelA continuous model is a decision model run in continuous time rather than fixed cycles, so health events can occur at any moment, governed by rates.
• Deterministic ModelA deterministic model produces the same output whenever its specified inputs, structure, and calculation rules are unchanged.
• Discrete ModelA discrete model represents at least one aspect of a system through distinct states, events, or time steps, allowing changes to be analysed as transitions among those elements rather than solely as continuously varying quantities.
• EquilibriumA state in an economic system where opposing forces, such as supply and demand, balance so there is no inherent tendency to change.
• Health Economic ModelA mathematical representation of the costs and health outcomes of alternative interventions over a defined time horizon, used when single-study data are insufficient.
• Linear Model HealthA statistical or decision-analytic model in which inputs and outputs are related by a simple linear function, such as a constant per-unit cost.
• Time DependencyThe property of a risk, effect, cost, utility or other model input changing according to a specified time scale, such as attained age or time since an event.