AMSTAR (A MeaSurement Tool to Assess systematic Reviews)
AMSTAR is a validated instrument designed to appraise the methodological quality of systematic reviews.
Paperguide Research Reference
Research Glossary
Every term defined with cited sources, real world examples, interactive learning, and the methodological depth that serious research demands.
Built for Researchers Who Need Precision, Not Guesswork
Evidence Synthesis Terms
The methods for bringing studies together: systematic reviews, meta analysis, scoping reviews and the reporting standards around them. These terms follow a review from the question and search strategy through screening, risk of bias and pooling to PRISMA reporting and GRADE.
A
Ancestry Approach
The ancestry approach is a supplementary search strategy used in systematic reviews to identify additional relevant studies by examining the reference lists of included articles and key review papers.
Automated Screening
Automated screening refers to the use of machine learning, natural language processing, or other computational algorithms to assist in the screening of titles, abstracts, or full texts during systematic reviews.
Automation Bias
Automation bias is the tendency of human decision makers to over rely on the output of automated systems, including artificial intelligence tools, even when contradictory information is available from other sources or from the decision maker's own judgment.
B
C
Cochrane Library
The Cochrane Library is a collection of databases containing high quality, independent evidence to inform healthcare decision making.
Cochrane Review
A Cochrane Review is a systematic review of primary research in healthcare and health policy produced by the Cochrane Collaboration, following a structured, transparent, and pre specified methodology set out in Cochrane's guidance, such as the Cochrane…
Critical Appraisal
Critical appraisal is the systematic process of evaluating research evidence to assess its trustworthiness, methodological quality, and relevance to a specific clinical, policy, or research question.
D
Data Extraction
Data extraction in the context of evidence synthesis is the systematic process of collecting predefined information from each study included in a systematic review, using a standardized form or template.
Dual Reviewer Screening
Dual reviewer screening is a methodological safeguard in systematic reviews in which two independent reviewers assess each study for inclusion at both the title and abstract screening stage and the full text screening stage.
E
Egger Test
The Egger test is a statistical method for detecting small study effects and potential publication bias in meta analysis.
Evidence Based Medicine (EBM)
Evidence based medicine (EBM) is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients.
Evidence Based Practice (EBP)
Evidence based practice (EBP) is the integration of the best available research evidence with professional expertise and the values and preferences of the individuals being served, to guide decisions in clinical, educational, social, and organizational…
Evidence Synthesis
Evidence synthesis is the process of systematically identifying, evaluating, and combining findings from multiple individual studies to draw broader, more reliable conclusions than any single study can provide.
Evidence to Decision Framework
An evidence to decision (EtD) framework is a structured approach used in guideline development to move from evidence appraisal to actionable recommendations by explicitly considering multiple criteria beyond the research evidence itself.
Exclusion Criteria
Exclusion criteria are the characteristics that disqualify a study or participant from being included in a research study or systematic review. These criteria are established before data collection begins and serve to create a well defined study population.
F
Fixed Effect Model
A fixed effect model in meta analysis is a statistical approach that assumes all studies in the analysis are estimating a single common (fixed) treatment effect, and that any variation between study results is due solely to random sampling error.
Forest Plot
A forest plot is a graphical display used in meta analyses to present the results of individual studies and the overall pooled estimate in a single figure.
Full Text Screening
Full text screening is the stage in a systematic review where the complete texts of potentially relevant studies, identified during title and abstract screening, are retrieved and read in full.
Funnel Plot
A funnel plot is a graphical tool used in meta analyses to visually assess whether publication bias or other small study effects may be present.
Funnel Plot Asymmetry
Funnel plot asymmetry refers to a systematic departure from the expected symmetrical inverted funnel shape when study effect estimates are plotted against their precision in a meta analysis.
G
GRADE (Grading of Recommendations Assessment, Development and Evaluation)
GRADE is a systematic and transparent framework for rating the certainty (quality) of a body of evidence and for developing and presenting recommendations in health care.
Grey Literature
Grey literature refers to research and information produced by organizations outside of traditional commercial and academic publishing channels.
H
I
I Squared (I²)
I squared (I²) is a statistic used in meta analysis to quantify the percentage of variability in effect estimates across studies that is attributable to true heterogeneity rather than sampling error.
Inclusion Criteria
Inclusion criteria are the predefined characteristics that a study participant, data source, or published study must possess to be eligible for enrollment in a research study or for selection in a systematic review.
Individual Participant Data (IPD)
Individual participant data (IPD) refers to the raw, observation level data collected for each participant in a clinical study, as opposed to the aggregate summary statistics reported in published articles.
L
Literature Review
A literature review is a comprehensive survey, critical analysis, and synthesis of existing published research on a specific topic.
Living Systematic Review
A living systematic review is a systematic review that is continually updated, incorporating new evidence as it becomes available rather than remaining a static document fixed at the time of publication.
M
Meta Analysis
Meta analysis is a statistical method that combines the quantitative results of multiple independent studies addressing the same research question to produce a single, more precise summary estimate of the effect.
Meta Regression
Meta regression is a statistical extension of meta analysis that examines whether study level characteristics (covariates) explain variation in effect sizes across studies.
N
Narrative Review
A narrative review is a type of literature review that summarizes, synthesizes, and interprets a body of research on a specific topic using a qualitative, discursive approach rather than the formal, predefined search and appraisal methods used in systematic…
Narrative Synthesis
Narrative synthesis is a method of synthesizing findings from multiple studies using words, text, and structured reasoning rather than statistical pooling.
Network Meta Analysis
Network meta analysis (NMA), also known as mixed treatment comparison, is a statistical technique that simultaneously compares three or more interventions by combining both direct evidence (from head to head trials) and indirect evidence (inferred through a…
O
P
Prediction Interval
In meta analysis, a prediction interval is a range that estimates where the true effect in a new study drawn from the same population of studies would be expected to fall.
PRISMA (Preferred Reporting Items for Systematic Reviews and Meta Analyses)
PRISMA is a reporting guideline that provides a standardized checklist and flow diagram for the transparent and complete reporting of systematic reviews and meta analyses.
PRISMA Flow Diagram
The PRISMA flow diagram is a standardized graphical representation that documents the number of records identified, screened, assessed for eligibility, and included or excluded at each stage of a systematic review.
Publication Bias
Publication bias is the systematic tendency for studies with positive, statistically significant, or novel results to be published more frequently and more promptly than studies with null, negative, or inconclusive findings.
Q
QUADAS 2 (Quality Assessment of Diagnostic Accuracy Studies)
QUADAS 2 is a structured quality assessment tool designed to evaluate the risk of bias and concerns about applicability in primary diagnostic accuracy studies included in systematic reviews.
Quality Assessment
Quality assessment is the evaluation of individual studies included in a systematic review for their methodological rigor, examining potential sources of bias, confounding, and reporting deficiencies that could affect the validity and reliability of their…
R
Random Effects Model
A random effects model is a statistical framework used in meta analysis that assumes the true treatment effect varies across studies, rather than being identical.
Rapid Review
A rapid review is a form of evidence synthesis that uses simplified or abbreviated systematic review methods to produce findings within a shorter timeframe, typically weeks to a few months rather than the one to two years a full systematic review often takes.
Reporting Bias
Reporting bias refers to systematic differences between reported and unreported research findings, encompassing both selective reporting of outcomes within individual studies and selective publication of entire studies based on the nature or direction of…
Research Synthesis
Research synthesis is the process of combining, analyzing, and interpreting findings from multiple individual studies on a particular topic to produce a comprehensive understanding that transcends what any single study can provide.
Risk of Bias
Risk of bias refers to the likelihood that the design, conduct, or analysis of a study has introduced systematic errors that could lead to an inaccurate estimate of the true effect.
Risk of Bias Assessment
Risk of bias assessment is the structured, systematic evaluation of the potential for systematic errors in a study's design, conduct, analysis, or reporting that could lead to over or underestimation of the true effect.
S
Scoping Review
A scoping review is a type of evidence synthesis that systematically maps the key concepts, types of evidence, and gaps in research on a broad topic area.
Search Strategy
A search strategy is a structured, documented plan for identifying relevant studies in bibliographic databases and other sources, specifying the databases to be searched, the search terms (including subject headings and free text words), the Boolean…
Synthesis Without Meta Analysis (SWiM)
Synthesis Without Meta Analysis, abbreviated SWiM, is a reporting guideline for systematic reviews of intervention effects that combine findings from multiple studies when statistical pooling through meta analysis is not feasible or appropriate.
Systematic Review
A systematic review is a rigorous, transparent, and reproducible research method that identifies, evaluates, and synthesizes all available evidence relevant to a clearly formulated research question.