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.
A
- Aggregate Data Meta-AnalysisAD Meta-Analysis, Summary Data Meta-Analysis
- A technique combining summary results, such as reported means or event rates, from multiple studies into a single pooled estimate.
B
- Bayesian Meta-AnalysisBayesian Evidence Synthesis, Bayesian Pooling
- An approach combining evidence across studies using Bayesian methods, formally incorporating prior information to produce a posterior effect estimate distribution.
- Begg TestBegg Rank Correlation Test, Begg and Mazumdar Test
- A statistical test for detecting publication bias in a meta-analysis, based on the rank correlation between effect size and its variance.
C
- Comparative EvidenceRelative-Effect Evidence, Comparative Effect Data
- Data comparing the relative effects of two or more interventions, whether from a direct head-to-head trial or indirect network meta-analysis.
- ConsistencyDirect-Indirect Agreement, Network Coherence
- Within network meta-analysis, the property that direct and indirect evidence for the same treatment pair agree with one another.
- Copas ModelCopas Selection Model, Publication Bias Model
- A statistical model adjusting a meta-analysis result for potential publication bias by modelling how publication likelihood depends on results.
D
- Direct EvidenceWithin-Trial Comparative Evidence, Direct Trial Evidence
- Within network meta-analysis, evidence comparing two treatments from trials in which those treatments were directly compared, unlike indirect evidence.
F
- Fixed Effect ModelCommon-Effect Model, Fixed-Effect Meta-Analysis
- A meta-analysis model assuming all included studies estimate the same true effect, with observed variation attributed entirely to sampling error.
- Forest PlotForest Diagram, Blobbogram
- A graphical display presenting each study's estimate and confidence interval alongside a meta-analysis's overall pooled result, typically as horizontal lines and a diamond.
- Frequentist Meta-AnalysisClassical Meta-Analysis, Frequentist Evidence Synthesis
- An approach combining evidence using classical frequentist methods, producing a point estimate and confidence interval without formally incorporating prior beliefs.
I
- I-SquaredI2 Statistic, Higgins I2
- A statistic quantifying the percentage of total variation across studies in a meta-analysis attributable to genuine heterogeneity rather than chance.
- InconsistencyDirect-Indirect Discrepancy, Evidence Discordance
- Within network meta-analysis, a discrepancy between direct and indirect evidence for the same comparison, indicating the two sources disagree.
- Indirect EvidenceIndirect NMA Evidence, Chained Evidence
- Within network meta-analysis, evidence comparing two treatments derived through a chain of comparisons via a common comparator, not from direct trials.
- Individual Patient Data Meta-AnalysisIPD Meta-Analysis, IPD-MA, Individual Participant Data Meta-Analysis, Participant-Level Meta-Analysis, Patient-Level Meta-Analysis
- Individual patient data meta-analysis systematically obtains, checks, and jointly synthesises participant-level records from eligible studies to estimate effects and investigate variation across studies or patients.
- Individual Patient Meta-Analysis
- An evidence synthesis approach combining original patient-level records from multiple studies into one unified dataset, rather than only summary statistics.
L
- League Table
- A table from a network meta-analysis displaying every treatment's estimated relative effect against every other treatment, organised for pairwise lookup.
M
- Meta-AnalysisEffect-Size Pooling, Pooled Analysis
- Meta-analysis statistically combines effect estimates from multiple studies addressing a sufficiently similar question.
- Multivariate Meta-AnalysisMVMA, Joint Meta-Analysis
- A meta-analysis method jointly analysing two or more related outcomes simultaneously, accounting for the correlation between them.
N
- Network GeometryNetwork Shape, Evidence Network Structure
- The overall structure and pattern of connections formed by trials in a network meta-analysis, showing which treatments were compared directly.
- Network Meta-AnalysisNMA, Multiple-Treatments Meta-Analysis, Mixed Treatment Comparison, MTC
- Network meta-analysis, or NMA, compares three or more interventions by combining direct evidence from head-to-head studies with indirect evidence connected through common comparators.
- Network Meta-Analysis HTANMA in HTA, NMA for Reimbursement
- The application of network meta-analysis specifically within health technology assessment, generating comparative effectiveness estimates when treatments were never studied together.
- Node-SplittingNode-Split Model, Inconsistency Check
- A technique testing for inconsistency in a network meta-analysis by separately estimating direct and indirect evidence for one comparison and comparing them.
O
- One-Stage Meta-AnalysisOne-Step Meta-Analysis, IPD One-Stage Model
- An individual patient data meta-analysis analysing combined patient-level data from all studies within a single unified statistical model.
P
- P-ScoreFrequentist SUCRA, Frequentist Ranking Probability
- A frequentist network meta-analysis measure ranking treatments by the extent one is expected to outperform every other treatment in the network.
- Pairwise Meta-AnalysisStandard Meta-Analysis, Direct Meta-Analysis
- A meta-analysis combining evidence comparing exactly two treatments, unlike a network meta-analysis synthesising evidence across three or more.
S
- Sensitivity SynthesisSensitivity Meta-Analysis, Leave-One-Out Analysis
- A supplementary meta-analysis testing how pooled results change when specific studies are excluded or alternative models or criteria are applied.
- Small Study EffectsSmall-Study Bias, Small Trial Effect
- A pattern in meta-analysis where smaller studies tend to report systematically larger treatment effects than larger studies, possibly reflecting publication bias.
- SUCRASurface Under the Cumulative Ranking Curve, Cumulative Ranking Probability
- An abbreviation for the surface under the cumulative ranking curve, ranking treatments in a Bayesian network meta-analysis by probability of being most effective.
T
- Tau-SquaredHeterogeneity Variance, Between-Study Variance
- A statistical parameter representing the estimated variance of the true treatment effect across studies in a random effects meta-analysis.
- Transitivity
- A key network meta-analysis assumption that treatments compared indirectly are similar enough in relevant characteristics for the comparison to be valid.
- Treatment Network
- The complete set of treatments and connecting trials forming the basis for a network meta-analysis, typically shown as nodes and connecting lines.
- Treatment Ranking
- The ordering of treatments in a network meta-analysis by estimated relative effectiveness, often summarised using measures such as SUCRA or P-scores.
- Two-Stage Meta-AnalysisTwo-Step Meta-Analysis, Aggregate-Then-Pool Analysis
- An individual patient data meta-analysis first analysing each study separately, then combining the resulting study-level estimates using standard methods.