Statistical Fit
A measure of how well a specified statistical model's predictions align with observed data, judging whether the specification adequately fits the pattern.
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.
Statistical Power
The probability that a statistical test will correctly detect a true effect of a specified size, calculated as one minus the beta level.
Statistical Significance
A judgement that an observed result is unlikely to have occurred by chance under the null hypothesis, based on a p-value below a threshold.
Steady State
A pharmacokinetic condition where a drug's concentration remains stable because the rate of administration equals the rate of elimination.
Step-Down Allocation
A method of allocating support department costs to operating departments in sequence, so that once allocated, no further costs return to that department.
Stochastic Analysis
An analysis in which a model incorporates randomness explicitly, so repeated runs under the same inputs can produce different results, unlike a deterministic model.
Stochastic Programming
An optimisation framework incorporating parameter uncertainty directly into the process, seeking a solution that performs well across possible parameter values.
Stock and Flow Model
A system dynamics structure representing accumulations, called stocks, such as infected individuals, and the rates of change into and out of them, called flows.
Stratified Log-Rank
A variant of the log-rank test accounting for stratifying variables, comparing survival within each stratum before combining into an overall statistic.
Stratified Sampling
A sampling technique dividing a population into distinct subgroups, called strata, and drawing a separate sample from each to ensure adequate representation.
Strict Dominance
A situation where one intervention is unambiguously better than another because it is both less costly and more effective.
Structural Equation Model
A modelling framework combining factor analysis and regression to test hypothesised relationships among observed and unobserved, latent variables.
Structural Sensitivity Analysis
A sensitivity analysis testing how results change under alternative structural assumptions, such as a different survival extrapolation function, rather than parameter values.
Structural Uncertainty
Uncertainty from the choice of a model's fundamental structure or method, such as which health states to include, unlike parameter uncertainty within a given structure.
Studentized Residual
A standardised residual excluding an observation's own contribution to the model fit, a more robust diagnostic for identifying influential data points.
Suits Index
A measure of the progressivity of a tax or financing system, using a concentration curve plotting cumulative tax burden against cumulative income.
Supplier-Induced Demand
The phenomenon in which providers, using their informational advantage, influence the quantity or type of care demanded beyond what informed patients would choose.
Supply
The quantity of a good or service producers are willing and able to offer for sale at a given price over a specified period.
Supply Curve
A graph showing the relationship between price and the quantity producers are willing to supply, typically sloping upward as price rises.
Survival Analysis
A branch of statistics concerned with the time until an event of interest occurs, appropriately accounting for censored observations.