Dictionary

L

Level of EvidenceTermEvidence Level, Evidence Hierarchy Rank

A classification ranking a study design's strength based on its susceptibility to bias, placing randomised trials above case reports or opinion.

Levels of CareTermCare Levels, Tiers of Care

In health systems, the tiers at which care is organised and accessed, from primary through secondary and tertiary to quaternary care, structuring referral pathways and resource use.

Leverage PointConceptLeverage Observation, Unusual Predictor Point

An observation with an unusual combination of predictor values, distinct from the bulk of the data, capable of disproportionately influencing a regression model.

LicensingTermLicensure, Operating Authorisation

The formal governmental authorisation required for a healthcare professional or organisation to legally practice within a given jurisdiction.

Licensing PolicyTermLicensure Policy, Licensing Framework

Government or professional body policy governing the requirements and process for granting formal authorisation to practice within a healthcare field.

Life ExpectancyConceptExpected Lifespan, Average Years Remaining

The expected number of additional years lived from a specified age under a stated set of mortality rates.

Life TableConceptMortality Table, Actuarial Table

A structured table that follows a hypothetical population through age or time intervals to summarize deaths, survivors, person-years, and expected remaining life.

Life Table MethodConceptActuarial Method, Life-Table Method, Actuarial Life-Table, Cohort Life-Table Estimation

The life table (actuarial) method estimates survival from deaths and withdrawals in fixed intervals, treating withdrawals as at risk for half an interval.

Life-Sustaining TreatmentTermLife Support, Life-Prolonging Treatment

Medical interventions, such as mechanical ventilation, used to prolong life without necessarily curing or reversing the underlying condition.

Lifecycle ManagementTermProduct Life-Cycle Management, Brand Lifecycle Strategy, Lifecycle Plan

The strategic planning of activities maximising a product's commercial value over its market life, including label expansions and new formulations.

Lifecycle PricingTermLifecycle Price Management, Life-Cycle Pricing Strategy

The strategy governing how a treatment's price is managed over its entire market life, from launch through patent expiry and generic competition.

Lifestyle InterventionTermBehavioural Lifestyle Programme, Lifestyle Modification

A programme modifying health-related behaviours, such as diet or smoking, used as a standalone preventive strategy or within disease management.

Lifetime CostTermLifetime Healthcare Cost, Whole-of-Life Cost

The total expected healthcare expenditure a patient will incur over the remainder of their life, related to a condition and sometimes unrelated future costs.

Lifetime HorizonTermLifetime Time Horizon, Whole-of-Life Horizon

A time horizon for an economic evaluation extending over the remaining expected lifespan of the population studied, rather than a shorter follow-up period.

Lifetime MaximumTermLifetime Limit, Lifetime Benefit Cap

A cap on the total amount an insurance plan will pay toward covered costs over an individual's entire coverage duration.

Lifetime PrevalenceTermCumulative Prevalence, Ever-Prevalence

The proportion of a population that has experienced a condition at any point in life up to assessment, unlike point prevalence.

Lifetime ValueTermWhole-of-Life Value, Longitudinal Patient Value

A component of a technology's value reflecting its cumulative benefit over a patient's remaining lifetime, particularly relevant for curative treatments.

Likelihood RatioConceptLR, Test Result Weight

A ratio comparing the likelihood of the same observed evidence under two specified conditions or statistical models.

Likelihood Ratio TestConceptLRT, Deviance Test

A statistical test comparing the fit of two nested models by their ratio of likelihoods, used to judge whether added parameters improve fit.

LimitationTermFunding Caveat, Recommendation Restriction

A specific restriction on a positive funding recommendation, such as limiting coverage to a defined subgroup or requiring prior treatment failure.

Limited CodeTermPartial Code, Modified Code Status

A designation specifying only certain, not all, resuscitative measures should be attempted, an intermediate option between full code and DNR.

Limited Data SetTermLDS, De-Identified Data Set

A US privacy category of health data with most direct identifiers removed but retaining elements such as dates, requiring a data use agreement.

Limited Societal PerspectiveTermRestricted Societal Perspective, Modified Societal Perspective

An analytic viewpoint including healthcare sector costs along with a defined subset of non-healthcare costs, such as informal carer time, short of a full societal view.

Line ExtensionTermBrand Extension, New-Formulation Variant

The development of a new version or formulation of an already-approved drug, such as an extended-release form, intended to extend the product's lifecycle.

Line-Item BudgetTermLine-Item Budgeting, Object-of-Expenditure Budget

A budget format specifying allocated spending for each individual expense category, such as salaries and supplies, rather than by programme.

Linear Model HealthTermLinear Predictor Model, Health Linear Model

A statistical or decision-analytic model in which inputs and outputs are related by a simple linear function, such as a constant per-unit cost.

Linear PoolConceptLinear Opinion Pool, Weighted Linear Aggregation

A method combining multiple experts' probability distributions by taking a weighted arithmetic average, producing a single pooled distribution.

Linear ProgrammingConceptLP, Linear Optimisation Model

Linear programming identifies the best feasible allocation of limited resources when the objective and constraints can be expressed as linear relationships.

Linear Programming HealthConceptHealth LP, Health Resource Optimisation

An optimisation technique identifying the resource allocation that maximises or minimises a linear objective subject to linear constraints, such as a fixed budget.

Linear RegressionConceptOLS Regression, Least-Squares Regression

A modelling technique estimating the linear relationship between a continuous outcome and one or more predictors, giving expected change per unit predictor.

Linked DataTermData Linkage, Linked Datasets

Information combined from two or more separate data sources, such as clinical records and claims, connected at the individual patient level.

Lipid ManagementTermCholesterol Management, Dyslipidaemia Management

The clinical process of assessing and treating blood cholesterol and lipid levels to reduce cardiovascular risk, combining counselling and statin therapy.

Liquid BiopsyTermCirculating Tumour DNA Test, Blood-Based Biopsy

A diagnostic technique analysing cancer-related genetic material circulating in a patient's blood, a less invasive alternative to tissue biopsy.

Liquidity RatioConceptCash Position Ratio, Short-Term Liquidity Measure

A liquidity ratio is a financial measure comparing an organisation’s readily available or current assets with its near-term obligations to assess its capacity to meet payments as they fall due.

List PriceTermSticker Price, Catalogue Price

The publicly stated price a manufacturer offers a drug for sale, before accounting for negotiated discounts or rebates that reduce the price actually paid.

Listing DecisionTermPositive Listing, Reimbursement Listing

A formal determination on whether a treatment will be included on a health system's approved formulary, and under what conditions.

Listwise DeletionConceptCasewise Deletion, Complete-Record Analysis

A missing data method excluding any observation with a missing value on any variable in an analysis, using only complete cases.

Literature SearchTermBibliographic Search, Evidence Search

The systematic process of querying bibliographic databases and other sources to identify relevant studies, using a predefined, documented strategy.

Liver Disease EconomicsTermHepatic Disease Economics, Hepatic Illness Economics

The application of health economic evaluation to conditions affecting the liver, spanning viral hepatitis, fatty liver disease, cirrhosis, and liver failure.

Liver Transplant EconomicsTermHepatic Transplant Economics, Liver Graft Economics

The application of health economic evaluation to liver transplantation, weighing procedure and lifelong immunosuppression costs against survival benefit for end-stage disease.

Living GuidelineTermContinuously Updated Guideline, Dynamic Clinical Guideline

A clinical guideline continually updated as new relevant evidence emerges, rather than published once and left static.

Living ReviewTermLiving Systematic Review, Continuously Updated Review

A systematic review continually updated as new relevant evidence becomes available, rather than conducted once and left static.

Living WillTermEnd-of-Life Directive, Personal Directive

A type of advance directive documenting an individual's preferences for future medical treatment, particularly life-sustaining interventions, if they cannot communicate.

Loading DoseTermInitial Dose, Priming Dose

An initial, often larger than standard, dose given to rapidly reach a therapeutic drug concentration before switching to a smaller maintenance dose.

Loan FinancingTermHealth Sector Borrowing, Credit-Based Financing

The use of borrowed funds, repaid over time with interest, to finance healthcare infrastructure or, at household level, medical expenses.

Local AdaptationTermCountry Adaptation, Local Contextualisation

The process of modifying evidence or guidance from another setting to reflect specific local clinical practice, resources, and population.

Local PerspectiveTermSub-National Perspective, Local Health Authority Perspective

An analytic viewpoint considering costs and outcomes relevant to a specific region or local health authority, rather than a national health system.

Local Sensitivity AnalysisTermLocal SA, Derivative-Based Sensitivity Analysis

A sensitivity analysis examining how output changes with small variations around a fixed base case for each parameter, unlike global sensitivity analysis.

Local Value DossierTermCountry Value Dossier, Local Payer Dossier

A country-specific document adapting a global health economic evidence package to a national health technology assessment body's requirements and comparators.

Log-Logistic DistributionConceptFisk Distribution, Loglogistic AFT Model

A two-parameter continuous distribution for positive event times whose logarithm is logistic; its survival function has a heavy tail, and its hazard may rise and then fall.