Dictionary
The Dictionary provides concise definitions of health economics terms, arranged alphabetically for quick reference. Use it to understand unfamiliar terminology or confirm the meaning of a specific term.
S
- Service Line ManagementTermService Line Model, Clinical Service Management
- An organisational approach grouping resources around specific clinical service areas, such as cardiology, rather than traditional departmental structure.
- Service ProcessTermService Activity, Entity Service Step
- The sequence of activities an entity undergoes while occupying a resource within a simulation model, along with its service time distribution.
- Service UtilisationTermHealthcare Utilisation, Service Use
- The extent to which a defined population uses a specific healthcare service, commonly measured as a rate per population over a period.
- Service VolumeTermActivity Volume, Delivered Volume
- The total quantity of a specific service delivered by a provider over a defined period, used as a measure of activity and experience.
- Severity CriterionTermSeverity Weighting, Disease-Burden Criterion
- A standard giving additional weight to interventions addressing more severe conditions, reflecting a preference for prioritising the greatest health shortfall.
- Severity ModifierTermSeverity Weight, Severity Adjustment Factor
- The severity modifier is a weight of 1.2 or 1.7 that NICE applies to QALY gains for conditions with a high absolute or proportional QALY shortfall.
- Severity of DiseaseTermDisease Severity, Condition Severity
- A measure of how serious a condition is, assessed by factors such as expected mortality or reduction in quality-adjusted life expectancy if untreated.
- Severity of IllnessTermIllness Severity, Clinical Severity Class
- A classification indicating how clinically serious a condition is, based on physiological instability and organ involvement, used to risk-adjust comparisons.
- Sexual FunctionTermSexual Functioning, Sexual Wellbeing
- A dimension of health-related quality of life capturing an individual's sexual health and functioning, affected by a range of conditions and treatments.
- SF-12Concept12-Item Short-Form Health Survey, Short Form 12, SF12
- SF-12 is a 12-item generic health survey taken from the SF-36 that gives physical and mental summary scores and can be scored as SF-6D utilities for QALYs.
- SF-36TermShort Form 36, RAND-36
- A widely used generic health status questionnaire measuring functioning and wellbeing across eight domains, producing a profile rather than a single utility score.
- SF-6DTermShort Form Six Dimension, SF6D Index
- A preference-based utility measure derived from a subset of SF-36 or SF-12 items, combined using a scoring algorithm into a single utility index.
- SF-6Dv2ConceptSF-6D version 2, Short-Form Six-Dimension version 2, SF6Dv2
- SF-6Dv2 is the revised SF-6D, a six-dimension preference-based classification scored from SF-36v2 answers, whose value sets give utilities for QALYs.
- SGRQConceptSt George's Respiratory Questionnaire, St. George's Respiratory Questionnaire
- SGRQ is the St George's Respiratory Questionnaire, a weighted 0 to 100 measure of health impairment in COPD and asthma, used in trials and mapped to EQ-5D.
- Shadow PriceConceptImplicit Price, Accounting Price
- The implicit value of a resource with no observable market price, reflecting the opportunity cost of using it in a particular way.
- Shadow Price of BudgetTermMarginal Value of Budget, Budget Shadow Price
- The implicit value of relaxing a fixed health budget by one extra unit of currency, reflecting the health forgone elsewhere if it is not spent optimally.
- Shadow Price of HealthConceptMarginal Value of Health, Health Opportunity Cost
- The implicit value of health gains forgone when a health budget is spent inefficiently, used as a basis for setting a cost-effectiveness threshold.
- Sheffield Elicitation FrameworkTermSHELF, Sheffield Elicitation Protocol
- A structured protocol eliciting probability distributions from a group of experts, combining individual assessment with facilitated group discussion toward a consensus.
- Short Physical Performance BatteryConceptSPPB
- Short Physical Performance Battery (SPPB) is a timed test of balance, gait speed and chair stands in older people, scored 0 to 12, used in trials.
- Short-Term OutcomeTermShort-Run Outcome, Proximal Outcome, Immediate Outcome, Early Outcome, Near-Term Outcome
- A clinical or economic outcome observed within a relatively brief period after treatment starts, unlike a long-term outcome requiring extended follow-up.
- Sign-OutTermShift Handover, End-of-Shift Report
- The transfer of information about a patient's condition and care plan from one clinician to another, typically at shift change.
- Signal DetectionTermSafety Signal Identification, Pharmacovigilance Signalling
- The process of identifying a potential new safety concern from surveillance data, typically from a disproportionate reporting pattern warranting investigation.
- Signal EvaluationTermSignal Assessment, Signal Investigation
- The process of investigating a potential safety signal from pharmacovigilance surveillance to determine whether it represents a genuine, causally related effect.
- SignalingConceptMarket Signalling, Costly Signalling
- An action taken by an informed party to credibly convey private information to an uninformed party that could not otherwise be verified.
- Signaling TheoryConceptTheory of Signalling, Spence Signalling
- A body of theory analysing how individuals with private information take costly actions to credibly reveal it in markets with information asymmetry.
- Significance LevelConceptAlpha Level, Significance Threshold
- The significance level is a prespecified upper bound on the probability that a valid statistical test rejects its null hypothesis when that hypothesis is true.
- Silver PlanTermSilver Tier Plan, Mid-Tier Marketplace Plan
- A US Affordable Care Act marketplace plan category with a moderate actuarial value, around seventy percent, serving as the subsidy benchmark tier.
- Simplification InterventionTermSimplification Nudge, Complexity Reduction
- An intervention that reduces the complexity of choices or information presented to a decision-maker to improve decision quality.
- Simpson ParadoxConceptSimpson's Paradox, Yule-Simpson Effect
- A statistical phenomenon where a trend seen within subgroups reverses or disappears once those subgroups are combined into a single aggregated analysis.
- Simpson RuleConceptSimpson's Rule, Parabolic Integration
- Simpson rule is a closed Newton-Cotes numerical integration formula that approximates a definite integral over pairs of equal subintervals by integrating quadratic interpolants through successive triples of function values.
- Simulated AnnealingConceptSA Optimisation, Annealing Optimisation
- An optimisation technique modelled on slowly cooling metal, occasionally accepting worse solutions during search to avoid becoming trapped in a poor local solution.
- Simulated Treatment ComparisonConceptSTC, Simulated Comparison
- A method comparing treatments from separate trials by fitting a regression model to one trial's data to predict outcomes for the other's population.
- Simulation MethodTermSimulation Approach, Computational Simulation
- A general approach to estimating a model's results by repeatedly running it computationally, rather than solving for results using closed-form equations.
- Simulation ModelTermSimulation-Based Model, In-Silico Model
- A model that mimics a real-world system's behaviour over time, letting analysts project outcomes under different scenarios without observing the real system.
- Single Attribute UtilityTermSingle-Dimension Utility, One-Attribute Utility
- A utility value derived from a single dimension of health or outcome, unlike multi-attribute utility, which integrates several dimensions.
- Single ImputationTermSingle Value Imputation, Deterministic Imputation
- A missing data method replacing each missing value with a single estimated substitute, unlike multiple imputation, which generates several plausible values.
- Single Payer SystemTermSingle Payer, Single-Payer
- A financing model where a single public entity finances healthcare for an entire population, while care may still be delivered by mixed providers.
- Single Technology AssessmentTermSTA, Single-Product Appraisal
- An assessment process focused on a single specific technology, typically a newly launched drug, unlike a multiple technology assessment.
- Single-Arm TrialTermSingle-Arm Study, Uncontrolled Trial
- A trial design in which all participants receive the same treatment without a concurrently randomised comparator, assessed against historical or external data.
- SIR ModelConceptSusceptible-Infectious-Recovered Model, SIR Compartmental Model
- A basic epidemic model dividing a population into susceptible, infectious, and recovered compartments, representing flow between them using differential equations.
- Six Sigma MethodologyTermSix Sigma, DMAIC Methodology, Six Sigma Healthcare, Healthcare Six Sigma, Six Sigma in Health
- A data-driven quality improvement methodology, from manufacturing, using statistical methods to identify and eliminate defect causes and reduce process variation.
- Six-Minute Walk TestConcept6MWT, 6-Minute Walk Test, Six-Minute Walk Distance, 6MWD
- Six-minute walk test (6MWT) is a performance outcome that records distance walked in six minutes, used as an endpoint in heart and lung trials and in HTA.
- SkewnessConceptDistribution Asymmetry, Skew
- A measure describing a distribution's asymmetry around its mean, positive skewness meaning a longer tail toward higher values.
- Skill MixTermStaffing Mix, Workforce Composition
- The specific combination and balance of different healthcare professional types, such as physicians and nurses, employed within a health system.
- Skilled Birth AttendanceTermSkilled Attendance at Birth, SBA Coverage
- A measure of the proportion of births attended by a trained healthcare professional, such as a doctor or midwife, a maternal health indicator.