Dictionary

M

Mental Health EconomicsConceptPsychiatric Economics, Behavioural Health Economics, Economics of Adolescent Mental Health

The broad application of health economic evaluation to mental health conditions and treatment, spanning prevention, psychotherapy, medication, and specialist psychiatric services.

Mental Health ParityTermParity Law, Behavioural Health Parity

A policy principle, and in some places a legal requirement, that insurance coverage for mental health treatment be no more restrictive than for physical health.

Mental Health PolicyTermMH Policy, Psychiatric Policy

Government or organisational policy governing the financing, delivery, and regulation of mental health services, covering insurance parity and community funding.

Mental Health PreventionTermPsychological Prevention, Behavioural Health Prevention

Interventions aimed at preventing mental health conditions or reducing their severity through early identification, spanning universal and targeted approaches.

Mental Health Service CoverageTermBehavioural Health Coverage, Psychiatric Service Coverage

A measure of the extent to which a population has access to needed mental health diagnosis and treatment services.

Merit GoodTermMeritorious Good, Socially Encouraged Good

A good society deems worthy of consumption regardless of an individual's own willingness to pay for it, often subsidised by government.

Meta-AnalysisConceptEffect-Size Pooling, Pooled Analysis

Meta-analysis statistically combines effect estimates from multiple studies addressing a sufficiently similar question.

Meta-RegressionConcept

Meta-regression is a precision-weighted regression of study effect estimates on study characteristics, explaining heterogeneity in meta-analyses for HTA.

Meta-Regression TransferTermMeta-Regression Benefit Transfer, Regression-Based Transfer

A form of benefit transfer in which a regression model estimated across many original studies predicts a value for a new context based on its characteristics.

Metal TierTermCoverage Tier, Plan Metal Level

A US Affordable Care Act classification categorising plans, such as bronze, silver, gold, and platinum, by their actuarial value.

MetamodelTermModel Emulator, Response-Surface Model

A simplified statistical approximation of a more complex model, built to run faster while still capturing its essential input-output relationships.

MetastasisTermMetastatic Spread, Secondary Tumour

The spread of cancer cells from the original tumour site to other parts of the body, typically indicating more advanced disease.

Method of MomentsConceptMoM, Moment Estimation

A technique estimating a distribution's parameters by equating sample moments, such as mean and variance, to their theoretical population equivalents.

Methodological QualityTermStudy Quality, Methodological Rigour

An overall assessment of whether a model or study followed accepted good practice standards, covering comparator choice, time horizon, and reporting transparency.

Methodological UncertaintyTermMethods Uncertainty, Analytic Uncertainty

Uncertainty arising from the choice of analytical methods or structural assumptions, such as discount rate, rather than the numerical values used within a fixed method.

Metropolis-HastingsConceptMH Algorithm, Metropolis Algorithm

A Markov chain Monte Carlo algorithm generating samples by proposing candidate values and accepting or rejecting them by a rule ensuring convergence.

MHRATermMedicines and Healthcare products Regulatory Agency, UK Medicines Regulator

The Medicines and Healthcare products Regulatory Agency, the UK body responsible for the safety, quality, and efficacy of medicines and devices.

Micro-CostingConceptDetailed Resource Costing, Micro-Level Cost Analysis

Micro-costing is a detailed method of estimating the cost of healthcare activities by identifying and measuring their individual resource components and valuing each component with an appropriate unit cost.

MicroinsuranceTermMicro-Insurance, Low-Income Health Insurance

A small-scale insurance product providing affordable financial protection to low-income individuals, often in settings lacking formal comprehensive insurance.

MicrosimulationConceptMicro-Simulation, Agent-Level Simulation, Individual Sampling Model

Microsimulation models individuals one at a time, allowing their characteristics and event histories to influence future outcomes.

Middle-Income CountryTermMIC, Middle-Income Economy

A country classified by gross national income per capita as falling within an intermediate tier of an international income classification system.

Mild Cognitive ImpairmentTermMCI, Pre-Dementia Impairment

A clinical state involving noticeable cognitive decline beyond what is expected for age, but not severe enough to significantly impair daily independent functioning.

Milestone AnalysisTermMilestone Survival, Fixed-Timepoint Analysis

A survival technique examining the proportion of patients event-free at a specific, predefined follow-up time, rather than reporting a full curve.

Mini-HTATermMini Health Technology Assessment, Rapid Hospital HTA

A simplified, abbreviated form of assessment for use at hospital or department level, typically applied to lower-cost or lower-risk technologies.

Minimal Clinically Important DifferenceConceptMCID, Minimal Important Difference

The minimal clinically important difference (MCID) is the smallest change in an outcome score that patients perceive as important, beneficial or harmful.

Minimal Residual DiseaseTermMRD, Molecular Residual Disease

The small amount of disease still detectable using highly sensitive techniques after treatment appears, by less sensitive measures, to have achieved complete response.

Minimal ResponseTermMinor Response, Slight Response

A response criterion indicating some improvement following treatment, but of a lesser degree than a partial or major response under disease-specific criteria.

Minimal RiskTermLow-Risk Threshold, De Minimis Risk

A regulatory classification indicating a study's anticipated harm probability and magnitude are no greater than those of ordinary daily life.

Minimally Invasive SurgeryTermMIS, Keyhole Surgery

Surgical techniques using smaller incisions and specialised instruments to reduce tissue damage compared with traditional open surgery, often shortening recovery.

Minimisation (Trial Allocation)ConceptMinimization

Minimisation is a trial allocation method steering each new participant to the arm best balancing chosen prognostic factors, often with a random element.

Minimum Effective DoseTermMED, Threshold Dose

The lowest drug dose that produces a clinically meaningful therapeutic effect, important for both safety and avoiding unnecessary medication cost.

Minimum Essential CoverageTermMEC, Qualifying Coverage

A regulatory standard defining the minimum insurance level required to satisfy an individual mandate, covering most employer, government, and marketplace plans.

Minimum NecessaryTermLeast-Data Principle, Need-to-Know Data Rule

A US privacy principle requiring only the minimum amount of protected health information necessary for a specific purpose be used or disclosed.

Minimum ValueTermMV Standard, Employer Plan Value Test

A US regulatory standard requiring an employer plan cover at least sixty percent of allowed benefit costs to satisfy the employer mandate.

Minor ConsentTermPaediatric Consent, Youth Consent

The legal authority of an individual below the age of majority to independently consent to specific categories of treatment, such as reproductive health.

MisclassificationConcept

Misclassification is recording people in the wrong category of exposure, outcome or covariate, which can bias effect, cost and outcome estimates.

Missing at RandomConceptMAR, Random Missingness

Missing at random is a missing-data mechanism in which, conditional on observed data, the probability of a missingness pattern does not depend on the values that remain unobserved.

Missing Completely at RandomConceptMCAR, Fully Random Missingness

A missing data classification indicating the probability of missingness is entirely unrelated to any observed or unobserved variables, the strongest assumption.

Missing DataConceptIncomplete Data, Data Missingness

Unobserved or unavailable values required for a specified analysis, whose consequences depend on the pattern, mechanism and target estimand.

Missing Data MethodsTermMissing Data Techniques, Incomplete-Data Methods, Missing Data Handling

Statistical techniques, from simple complete case analysis to multiple imputation, used to address incomplete data, chosen based on the likely missingness mechanism.

Missing Not at RandomConceptMNAR, Non-Ignorable Missingness

Missing not at random describes a missing-data mechanism in which the probability that a value is unobserved depends on that unobserved value even after conditioning on the available observed information.

MisuseTermImproper Utilisation, Non-Best-Practice Use

The use of a service in a manner inconsistent with best practice, resulting in an avoidable complication, unlike overuse or underuse.

Mixed Effects ModelConceptRandom-Coefficient Regression, Panel-Data Regression

A mixed effects model combines population-level fixed coefficients with probability-modelled variation across groups or individuals to analyse outcomes with clustered or repeated observations.

Mixed Model Repeated MeasuresTermMMRM, Repeated-Measures Mixed Model

A longitudinal trial analysis method using a mixed effects framework under the missing at random assumption, an alternative to last observation carried forward.

Mixed SystemTermHybrid Health System, Pluralistic System

A health system combining elements of multiple financing and delivery models, such as public and private insurance operating alongside one another.

Mixture Cure ModelConceptTwo-Component Survival Model, Incidence-Latency Model

A cure model treating the population as a mixture of a cured fraction facing only background mortality and an uncured fraction remaining at risk.

Mixture ModelConceptFinite-Component Mixture, Probabilistic Mixture

A statistical model representing a population as a combination of two or more distinct subgroups, each following its own underlying distribution.

Mobile HealthTermmHealth, Health on Mobile

The use of mobile devices, such as smartphones, to support healthcare delivery and public health practice, from reminders to disease management.

Mobile Health DataTermmHealth Data, App-Generated Data

Health-related information collected through smartphone apps or sensors, capturing activity, symptoms, or adherence in real time outside clinical settings.

ModeTermModal Value, Most Frequent Value

A central tendency measure representing the most frequently occurring value within a dataset.