Poisson Regression
A modelling technique analysing count outcome data, such as clinical events per patient, based on the assumption that outcomes follow a Poisson distribution.
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.
Polynomial Approximation
The representation of a function or dataset using a polynomial that provides a sufficiently accurate estimate over a specified interval.
Polynomial Interpolation
The construction of a polynomial that passes exactly through a specified set of data points to estimate intermediate values.
Pooling Equilibrium
A market outcome in which different risk types make the same choice, so a firm cannot distinguish between them from behaviour alone.
Population Attributable Fraction
The proportion of disease cases in an entire population that would not occur if a specific exposure were eliminated, accounting for its prevalence.
Population Attributable Risk
The reduction in disease incidence within a population that would result from eliminating a harmful exposure entirely, expressed as an absolute rate.
Population EVPI
The expected value of perfect information calculated for an entire affected patient population over time, rather than for a single patient.
Positive Externality
A benefit conferred on a third party by an economic activity, not reflected in its market price, leading to underproduction relative to the social optimum.
Positive Likelihood Ratio
A diagnostic test measure expressing how much a positive result increases the odds that a patient truly has the condition tested for.
Positive Predictive Value
The probability that an individual with a positive diagnostic test result truly has the condition being tested for.
Post-Test Probability
The updated probability that a patient has a condition after a diagnostic test result is known, combining pre-test probability with the likelihood ratio.
Posterior Distribution
In Bayesian statistics, the updated probability distribution for a parameter after combining a prior distribution with the likelihood of observed data.
Posterior Odds
The updated odds that a hypothesis is true after incorporating new evidence, found by multiplying prior odds by the likelihood ratio.
Posterior Probability
The updated probability of a hypothesis after accounting for observed evidence, combining a prior probability with the likelihood of that evidence.
Pre-Test Probability
The estimated probability that a patient has a condition before a diagnostic test result is known, based on prevalence and clinical presentation.
Predicted Cost
An estimate of expected future healthcare expenditure generated using a risk adjustment model incorporating demographics, diagnoses, and prior utilisation.
Prediction Error
The difference between a value predicted by a statistical model and the value that is actually observed.
Prediction Interval
A range calculated to contain a future individual observation with a specified confidence, unlike a confidence interval describing a population parameter.
Predictive Accuracy
The degree to which a model's forecasts or classifications correspond to actual observed outcomes when tested against real data.
Preference Weight
A numerical value reflecting the relative desirability a population or individual assigns to a particular health state or outcome.