Dictionary

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Theil Index HealthConceptHealth Theil Index, Theil Inequality Measure

An information theory based inequality measure applied to a health outcome's distribution, decomposable into inequality within and between population subgroups.

Theory Of ConstraintsTermTOC, Constraints Management

A management philosophy identifying the single most limiting factor preventing greater throughput toward a goal, and focusing improvement there first.

Therapeutic AreaTermTreatment Area, Indication Area, Clinical Area, Clinical Field, Medical Speciality Area, Disease Area, Condition Category, Assessment Area

A defined category of medical conditions or treatments, such as oncology, used to organise research, development, and assessment activities.

Therapeutic ClaimTermClinical Claim, Therapeutic Conclusion

Therapeutic claim, in a PBAC submission, classes a medicine as superior, non-inferior or inferior to its main comparator and sets the economic evaluation.

Therapeutic ClassTermDrug Class, Medication Class

A grouping of medications sharing a similar mechanism of action or used to treat the same condition, such as statins or beta-blockers.

Therapeutic CompetitionTermWithin-Class Competition, Treatment Competition

The competitive pressure exerted on a drug's pricing and market position by other treatments available for the same condition.

Therapeutic GoalTermTreatment Objective, Therapy Target, Treatment Goal

The specific clinical outcome a treatment strategy is intended to achieve, such as cure, symptom control, stabilisation, or preventing complications.

Therapeutic Group PremiumTermReference Group Premium, Therapeutic Reference Premium

The additional price a treatment commands over the reference price for its therapeutic group under internal reference pricing, requiring the difference paid separately.

Therapeutic IndexTermTherapeutic Ratio, Safety Margin Index

A drug's safety margin, calculated as the ratio between the dose that produces toxicity and the dose producing the desired effect.

Therapeutic InterchangeTermTherapeutic Swap, Protocol Substitution

Substituting a different medication within the same class for a prescribed drug, based on protocols indicating therapeutic equivalence, typically with physician notification.

Therapeutic MisconceptionTermTrial Misconception, Research Misconception

A phenomenon where a trial participant mistakenly believes their participation is meant to provide personalised treatment rather than generate scientific knowledge.

Therapeutic PrivilegeTermTherapeutic Exception, Physician Withholding

A limited, ethically contested exception to consent requirements in which a physician withholds information judged likely to cause significant psychological harm.

Therapeutic Reference PricingTermTherapeutic Class Reference Pricing, Class-Based Reference Pricing

A policy grouping drugs believed to produce similar therapeutic effects and setting one reference reimbursement level, encouraging use of the most cost-effective option.

Therapeutic ValueTermClinical Worth, Treatment Value

The clinical benefit a treatment provides for a condition, a core consideration within assessment frameworks that formally rate treatment benefit.

Third Party PerspectiveTermReimburser Viewpoint, Third-Payer Viewpoint

An analytic viewpoint including only costs and outcomes relevant to a third-party payer, such as an insurer, excluding costs borne directly by patients.

Third-Line TherapyTermThird-Line Treatment, Third-Line Regimen

A treatment used after both first-line and second-line treatments have failed to achieve adequate disease control or been discontinued.

Third-Party AdministratorTermTPA, Benefits Administrator

An organisation providing administrative services, such as claims processing, for a self-insured employer's plan, without bearing the claims' financial risk.

Third-Party PayerTermThird-Party Reimburser, Insurer-Payer

An entity, other than the patient or provider, that finances healthcare costs on behalf of a covered individual, such as an insurer.

Three-State ModelTermThree-Compartment Model, 3-State Markov Model

A simplified Markov structure with exactly three health states, commonly well, diseased, and death, used when a fuller structure is unnecessary.

Threshold AnalysisConceptThreshold Analysis Method, Switching-Value Analysis

Threshold analysis finds the switching value, the level an uncertain input must reach for the preferred option in a health economic model to change.

Threshold ApproachTermThreshold Decision Rule, Cost-Effectiveness Cut-Off Rule

A decision-making method that classifies an intervention as cost-effective or not based on whether its ICER falls below a predetermined threshold.

Threshold PriceConceptBreak-Even Price, Maximum Justifiable Price

Threshold Price is the highest price at which a health technology stays cost-effective: the price where its ICER equals the cost-effectiveness threshold.

ThroughputConceptOutput Rate, Processing Volume

Throughput is the number of patients or care episodes a health service completes per unit of time, such as discharges per day, counted at a defined exit.

Throughput EfficiencyTermFlow Efficiency, Processing Efficiency

A measure of how effectively a process moves patients through their care journey relative to the time and resources consumed.

Tiered AlertTermGraded Alert, Severity-Graded Alert

A computerised clinical alert system categorising notifications by severity, presenting more urgent alerts more prominently than lower-priority ones.

Tiered CareTermGraduated Care Tiers, Layered Care

A delivery model organising services into distinct levels of intensity, matching patients to the tier appropriate for their current clinical needs.

Tiered NetworkTermTiered Provider Network, Layered Network

A plan design categorising in-network providers into tiers by cost or quality, with lower cost-sharing for preferred-tier providers.

Tiered PricingTermPrice Tiering, Graduated Pricing

A pricing strategy charging different prices for the same product across markets, typically calibrated to differences in ability to pay.

Time DependencyConceptTime-Dependence, Temporal Dependence

The property of a risk, effect, cost, utility or other model input changing according to a specified time scale, such as attained age or time since an event.

Time HorizonConceptAnalytic Horizon, Evaluation Period, Horizon Choice, Analytic Horizon Decision

The span of time over which an economic evaluation captures relevant differences in costs and outcomes among the options being compared.

Time Horizon Selection HTATermHTA Time Horizon, Lifetime Horizon Selection

The methodological decision on how long a cost-effectiveness analysis should simulate costs and outcomes, often requiring a full lifetime horizon for chronic conditions.

Time on TreatmentTermToT, Duration on Therapy

The duration a patient continues receiving a specific therapy before discontinuation, whether from progression, intolerable effects, or achieving the treatment goal.

Time PreferenceConceptTemporal Discounting, Impatience Parameter

Time preference is the preference for benefits sooner and costs later; in health economics it is one reason future costs and QALYs are discounted.

Time Series DataTermTemporal Data, Time-Ordered Data

Data consisting of repeated measurements of the same variable collected sequentially over time, such as monthly disease incidence rates.

Time Series DesignTermTime Series Study, Serial Measurement Design, Time Series

A study design examining a sequence of observations on one population collected repeatedly over time, often to assess a policy's impact before and after.

Time StructureTermTemporal Structure, Model Timing Framework, Horizon Structure, Model Time Design, Cycle-Horizon Layout, Cycle Structure, Model Cycle Organisation, Temporal Model Structure

The way a model represents the passage of time, whether in fixed discrete cycles, as in a Markov model, or continuously.

Time to MarketTermSpeed to Market, Launch Timeline

The total elapsed time from a drug candidate's discovery to regulatory approval and market availability, often spanning a decade or more.

Time to ResponseTermResponse Time, Time until Response

The interval between the start of treatment and the point a patient meets a defined responder threshold on a relevant outcome measure.

Time Trade-OffConceptTTO, Life-Year Trade-Off

The time trade-off (TTO) values a health state for QALYs by asking how many years in full health a person rates equal to a longer life in that state.

Time Value of MoneyConceptTVM, Present Value Principle

The principle that a given sum of money is worth more today than the same sum received in the future.

Time with SymptomsTermSymptomatic Time, Time in Symptomatic State

A phase within the Q-TWiST framework representing the period during which a patient experiences symptoms of disease progression or treatment toxicity.

Time Without Symptoms of ProgressionConceptTWiST, Symptom-Free Progression-Free Time

Time without symptoms of progression (TWiST) is survival free of disease symptoms and counted treatment toxicity, the reference state in Q-TWiST.

Time-Driven Activity-Based CostingConceptTDABC, Time-Driven ABC

Time-driven activity-based costing (TDABC) costs health care by multiplying each resource's cost per minute of capacity by the minutes a patient uses.

Time-Fixed CovariateTermBaseline Covariate, Time-Invariant Covariate

A patient characteristic in a survival model measured once and assumed constant throughout follow-up, such as baseline age or sex.

Time-Homogeneous ModelConceptTime-Constant Model, Stationary Markov Model

A time-homogeneous model is a Markov model whose transition probabilities are the same in every cycle, so health state risks never change with age or time.

Time-Inhomogeneous ModelConceptTime-Varying Markov Model, Non-Stationary Model

A time-inhomogeneous model is a Markov model whose transition probabilities can change between cycles, so a risk such as death can rise as the cohort ages.

Time-Lag BiasConcept

Time-lag bias is distortion of the evidence available at a given time because studies with favourable or significant results are published sooner.

Time-to-EventConceptEvent-Time Outcome, Event-History Outcome

Time-to-event data record the time until an event such as death or progression, with some times censored, and supply survival inputs to economic models.

Time-Varying CovariateConceptTime-Dependent Covariate, Updating Covariate

A patient characteristic in a survival model allowed to change value over follow-up, such as a repeatedly measured biomarker.

Time-Varying HazardConceptTime-Dependent Hazard, Non-Constant Hazard

A hazard rate that changes in magnitude over follow-up, unlike a constant hazard that stays the same at every point.