Multilevel Model
A model representing nested data, such as patients within hospitals within regions, allowing relationships to vary at each level while sharing strength.
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.
Multiple Imputation
A missing data technique generating several plausible complete datasets with different estimated replacement values, then combining separate analyses of each.
Multivariate Sampling
The simultaneous drawing of random values for multiple correlated input parameters from their joint probability distribution, rather than sampling each independently.
Nash Equilibrium Health
A game theory solution in which no player can improve their outcome by unilaterally changing strategy, given the strategies chosen by others.
Negative Binomial
A discrete probability distribution modelling count data with more variability than a Poisson distribution would predict, known as overdispersion.
Negative Binomial Regression
A modelling technique analysing count outcome data, such as hospitalisations, that shows overdispersion relative to what a Poisson model would assume.
Negative Externality
A cost imposed on a third party by an economic activity, not reflected in its market price, leading to overproduction relative to the social optimum.
Nelder-Mead Method
A numerical optimisation algorithm searching for a function's minimum using a moving shape, called a simplex, without needing the function's derivative.
Nelson-Aalen Estimator
A non-parametric method for estimating the cumulative hazard function from censored data, closely related to the Kaplan-Meier estimator.
Net Benefit Approach
A framework for economic evaluation that converts health outcomes into money at a set value per unit of effect, then subtracts cost.
Net Budget Impact
The overall change in spending from adopting a new technology, after accounting for offsetting savings elsewhere, such as avoided hospital admissions.
Net Health Benefit
A summary measure expressing an intervention's value in health units, converting incremental cost into health forgone and subtracting it from health gained.
Net Margin
A financial ratio calculated as net income divided by total revenue, showing the proportion of revenue remaining as profit.
Net Monetary Benefit
A summary measure expressing an intervention's value in money, converting its incremental health effect into cash at a set threshold and subtracting incremental cost.
Net Present Value
The sum of a stream of future cash flows, each discounted to its present-day value, minus the initial cost of the investment.
Net Survival Model
A survival model estimating the survival a population would experience if the disease studied were the only possible cause of death.
Newton-Raphson Method
A numerical technique finding a function's roots by iteratively improving an initial guess using the function's value and derivative at each step.
Non-Mixture Cure Model
An alternative cure model structure formulating survival directly in terms of the cured fraction without explicitly splitting the population into two subgroups.
Non-Parametric Estimation
A statistical approach to estimating a survival function without assuming the data follow any specific mathematical distribution.
Non-Parametric Survival
Survival data or estimates obtained without assuming a specific distribution, such as a Kaplan-Meier curve calculated directly from observed trial data.