Secondary Research
Secondary research is research that summarises existing studies instead of collecting new data, as in systematic reviews and meta-analyses.
Encyclopaedia
Explore comprehensive, evidence-informed explanations of key health economics concepts, including their development, application and relationships to other concepts. Published entries are validated through human expert review.
Concepts, entries and ontology terms
A concept page is a published entry on the wiki. Some concepts also have a full encyclopaedia article. The Health Economics Ontology (HEO) holds every concept, including dictionary terms without an article, so it is larger than the list of published pages. The knowledge graph shows how concepts relate to each other.
SEIR Model
The SEIR model is a transmission model that adds an exposed, not yet infectious stage to the SIR model, used to evaluate vaccines and outbreak control.
Selection Model
A selection model handles missing trial data by modelling the outcome alongside the chance each value is observed, allowing for data missing not at random.
Self-Control Concept
The management of conflict between immediate incentives or effort and longer-term goals, especially when the timing of a choice changes what a person prefers to do.
Semantic Search
Semantic search is information retrieval that matches the meaning of a query, via a thesaurus, ontology or embeddings, to find studies or HTA guidance.
Sensitivity
The proportion of people with a specified target condition who test positive at a stated diagnostic threshold, calculated as true positives divided by true positives plus false negatives.
Sensitivity Analysis
Sensitivity analysis tests whether a health economic model's results and decision change when uncertain inputs, assumptions or model structure are varied.
Sentinel Event Rate
A sentinel event rate is the number of grave patient-safety events, such as wrong-site surgery, per unit of care activity in a set period.
Sequential Analysis
Sequential analysis tests trial or safety data as they accumulate and stops once preset evidence boundaries are crossed, not at a fixed sample size.
Sequential Monte Carlo
Sequential Monte Carlo (SMC) tracks a sequence of probability distributions with weighted samples to calibrate health models and update them with data.
SF-12
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-6Dv2
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.
SGRQ
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 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 Health
The shadow price of health is the health a fixed budget gains from one more pound spent at the margin; its reciprocal is the cost-effectiveness threshold.
Shadow Price of Labour
The shadow price of labour, or shadow wage, is a shadow price that values staff and volunteer time in health appraisal at its social opportunity cost.
Shapes Constraint Language
The Shapes Constraint Language (SHACL) is a W3C data standard for validating RDF data against stated rules, such as a discharge date following admission.
Shared Frailty
Shared frailty is an unobserved random effect, shared by all patients in a cluster such as one hospital, that scales their hazard in survival analysis.
Short Physical Performance Battery
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.
Signaling
Signaling is a costly, visible action by which an informed party, such as a hospital, credibly reveals hidden quality to patients or insurers.