Dictionary

R

Rejection RegionTermCritical Region, Reject Zone

In hypothesis testing, the range of test statistic values for which the null hypothesis would be rejected in favour of the alternative.

Relapse Period (REL)ConceptREL, Time After Relapse, Q-TWiST Relapse State

Relapse period (REL) is the Q-TWiST health state covering survival time after relapse or progression, weighted by its own utility.

Relapse-Free SurvivalConceptRFS, Relapse-Free Interval

Relapse-free survival (RFS) is the time from randomisation, or another stated start such as surgery, to relapse of the disease or death from any cause.

Related Future CostTermRelated Downstream Cost, In-Scope Future Spending

Future medical costs incurred in added years of life gained from treatment, arising from the same condition the original intervention addressed.

Relative Dose IntensityTermRDI, Delivered-Dose Ratio

A measure comparing the dose intensity a patient actually received to the originally planned, full dose intensity, expressed as a percentage.

Relative EffectivenessTermHead-to-Head Effectiveness, REA Result

A measure comparing how well a treatment performs against an alternative under real-world practice conditions, unlike relative efficacy measured under trial conditions.

Relative MeasureTermRatio Measure, Comparative Effect Metric

A measure of effect expressed as a ratio comparing two groups, such as relative risk, rather than as an absolute difference.

Relative RiskConceptRR, Risk Multiple

Relative risk compares the probability of an event in one group with the probability in another group over a defined period.

Relative Risk ReductionConceptRRR, Proportional Risk Reduction

The proportional reduction in risk associated with a treatment, calculated as one minus the relative risk, expressed as a percentage.

Relative SurvivalConceptPopulation-Adjusted Survival, Expected-Ratio Survival

A survival measure comparing observed survival in a population to expected survival in a comparable general population, without needing cause-of-death data.

Relative Survival ModelConceptExcess-Hazard Model, Population-Mortality Model

A statistical model estimating disease-specific survival by comparing observed survival against expected general population survival, without individual cause-of-death data.

Relative Value ScaleTermRVS, Resource-Based Value Scale

A system assigning a numerical value to each service reflecting its relative resource intensity, providing the structure for a standardised fee schedule.

Relative Value UnitConceptRVU, Service Value Unit

A relative value unit is a standardized weight assigned to a covered service component to represent its relative resource use within the US Medicare Physician Fee Schedule.

Relative WeightConceptCasemix Weight, Resource Intensity Weight

A numerical value assigned to a payment classification, such as a diagnosis-related group, reflecting its expected resource intensity relative to average.

Relevance AssessmentTermRelevance Appraisal, Applicability Appraisal

An evaluation of whether a model's structure, population, and outcome measures are appropriate for the specific decision question and audience it addresses.

Relevance CriterionTermRelevance Test, Pertinence Rule

A standard assessing whether a piece of evidence or consideration is genuinely pertinent to the specific decision being made.

Reliability AssessmentConceptReliability Testing, Reliability Evaluation

An evaluation of the consistency and reproducibility of an instrument's results, covering internal consistency, inter-rater, and test-retest reliability.

Remembered UtilityTermRecalled Utility, Retrospective Utility

The retrospective evaluation a person gives of a past experience or health state, which can differ from the utility actually experienced at the time.

Reminder InterventionTermPrompt Intervention, Cue-Based Intervention

An intervention using prompts, such as text messages or letters, to counteract forgetting or procrastination in completing a task.

Reminder SystemTermAutomated Reminder Tool, Prompt System

A technology-based tool sending prompts to patients or providers to encourage a desired health-related action, such as taking medication.

RemissionTermSymptom-Free State, Disease Quiescence

A state in which cancer signs and symptoms have reduced or disappeared following treatment, which may be complete or partial.

Remote MonitoringTermRPM, Remote Patient Tracking

The use of connected devices and digital technology to track a patient's health status outside a traditional clinical setting.

REMSTermRisk Evaluation and Mitigation Strategy, Risk Mitigation Programme

Risk Evaluation and Mitigation Strategy, a required manufacturer safety programme for medications with serious safety concerns, such as restricted distribution.

Renal Dosing AlertTermKidney-Function Dose Alert, Renal Dose Warning

A computerised notification warning a prescriber that a proposed dose may need adjustment given a patient's reduced kidney function.

Rent SeekingTermRent-Seeking Behaviour, Unproductive Profit-Seeking

The pursuit of increased wealth through manipulating the economic or political environment, rather than through creating new value via production.

Repeated MeasuresTermWithin-Subject Data, Repeated Observations

A study design in which the same outcome is measured multiple times on the same individuals, typically at different points in time.

Repeated Measures AnalysisTermRM-ANOVA, Within-Subject Analysis

A statistical approach analysing data in which the same outcome has been measured multiple times on the same individuals, accounting for correlation.

ReplicationTermSimulation Replications, Monte Carlo Runs

Running multiple independent repetitions of a stochastic simulation, each with its own randomly sampled numbers, to estimate output variability and confidence intervals.

Reporting BiasTermSelective Disclosure, Outcome Suppression

A broad category of bias arising when selective reporting of research findings, at study or outcome level, systematically distorts available evidence.

Reporting ErrorTermReport Data Error, Misreporting

A mistake occurring when study results are inaccurately transcribed, summarised, or presented in a publication, distinct from errors in collection or analysis.

Reporting StandardsTermReporting Guidelines, Publication Standards

The requirements governing how research findings, positive and negative, must be documented and disclosed, to prevent selective reporting bias.

Representativeness ConceptTermRepresentativeness Heuristic, Similarity Judgment

A cognitive heuristic in which the probability of an event is judged by how closely it resembles a typical case rather than actual likelihood.

ReproducibilityTermResult Consistency, Independent Verifiability

The ability of an independent party to obtain the same results as originally reported by rebuilding or re-running a model using documented methods.

Reproducible ComputingTermReproducible Analysis, Computational Reproducibility

A computational approach that enables analyses to be repeated and produce consistent results using the same data, methods and software environment.

Reproduction NumberTermR Number, Reproduction Rate

A general term for the average number of secondary infections one infected individual produces, covering both the basic and effective reproduction numbers.

Reproductive EpidemiologyTermFertility Epidemiology, Reproductive-Health Epidemiology

A branch of epidemiology studying factors affecting human fertility, reproductive health, and reproductive outcomes within populations.

Reproductive Health EconomicsTermFertility Health Economics, Reproductive Care Economics

The application of health economic evaluation to family planning, fertility, and reproductive healthcare services across the reproductive lifespan.

ReQoL-10ConceptRecovering Quality of Life 10-item measure, Recovering Quality of Life-10

ReQoL-10 is the 10-item Recovering Quality of Life questionnaire for mental health service users, scored as a total or as ReQoL-UI utilities for QALYs.

ReQoL-20ConceptRecovering Quality of Life 20-item measure, Recovering Quality of Life-20

ReQoL-20 is the 20-item Recovering Quality of Life questionnaire for mental health service users, used at assessment and as a trial and research outcome.

ReQoL-UIConceptRecovering Quality of Life Utility Index, ReQoL Utility Index

ReQoL-UI is a preference-based index scoring seven ReQoL items as utilities, so mental health studies can estimate QALYs for cost-utility analysis.

ResamplingTermSample Reuse, Repeated Subsampling

A family of statistical methods that draw repeated samples from observed data to estimate uncertainty or validate models, including the bootstrap, jackknife and cross-validation.

Research and Development CostTermR&D Cost, R&D Expenditure

The total expense a manufacturer incurs discovering, testing, and gaining regulatory approval for a treatment, spanning preclinical research through submission.

Research CostTermStudy Cost, Trial Development Cost

The total expected expense of conducting a proposed study, weighed against the expected value of sample information the study would generate.

Research EthicsTermHuman-Participant Protection, Ethical Research Conduct

The branch of applied ethics concerned with moral principles governing human subjects research, including respect for persons, beneficence, and justice.

Research IncentiveTermInnovation Incentive

A payment or benefit offered to encourage study participation, carefully calibrated to avoid becoming an undue inducement that compromises consent.

Research PrioritisationTermResearch Priority Setting, Study Prioritisation

The process of deciding which research studies to fund first, given limited resources, informed by formal value of information methods.

Research QuestionTermStudy Question, Research Aim

The specific, well-defined question a study or assessment is designed to answer, typically structured using a framework such as PICO.

Research RiskTermStudy Risk, Participant Risk

The potential for physical, psychological, social, or economic harm a participant may experience from taking part in a study.

Reservation PriceTermReserve Price, Maximum Acceptable Price

The maximum price a buyer is willing to pay for a good or service before deciding not to purchase it at all.

ResidualTermFitted-Value Error, Observed-Minus-Predicted

The difference between an observed value and the value predicted for it by a fitted statistical model.