12 min read

Statistical Synthesis

Meta-analysis, GRADE assessment, and forest plots

Statistical Synthesis

Transform extracted data into meaningful evidence summaries with automated meta-analysis and GRADE assessments.

Meta-Analysis Capabilities

Effect Measures

For Binary Outcomes

  • Risk Ratio (RR)
  • Odds Ratio (OR)
  • Risk Difference (RD)
  • Number Needed to Treat (NNT)

For Continuous Outcomes

  • Mean Difference (MD)
  • Standardized Mean Difference (SMD)
  • Weighted Mean Difference

For Time-to-Event

  • Hazard Ratio (HR)
  • Log Hazard Ratio

Analysis Models

Fixed-Effect Model

  • When studies are homogeneous
  • Single underlying effect assumed
  • Inverse variance weighting

Random-Effects Model

  • When heterogeneity exists
  • Accounts for between-study variance
  • DerSimonian-Laird or REML methods

Heterogeneity Assessment

Automatic calculation of:

  • I² statistic: Percentage of variability
  • Tau²: Between-study variance
  • Q statistic: Chi-squared test
  • Prediction intervals: Expected range for future studies

GRADE Assessment

Evidence Certainty

Rate confidence in your findings:

  • High: Very confident in estimate
  • Moderate: Moderately confident
  • Low: Limited confidence
  • Very Low: Very little confidence

Domains Assessed

Downgrading Factors

  1. Risk of bias
  2. Inconsistency
  3. Indirectness
  4. Imprecision
  5. Publication bias

Upgrading Factors

  1. Large effect
  2. Dose-response gradient
  3. Plausible confounding

Summary of Findings Tables

Automatically generated tables showing:

  • Each outcome
  • Relative and absolute effects
  • Number of studies and participants
  • Certainty rating
  • Plain language interpretation

Visualization Tools

Forest Plots

Publication-quality plots showing:

  • Individual study effects
  • Confidence intervals
  • Pooled estimate (diamond)
  • Weights
  • Heterogeneity statistics

Customization Options

  • Study labels
  • Subgroup divisions
  • Color schemes
  • Font sizes

Funnel Plots

Assess publication bias:

  • Study precision vs effect
  • Expected funnel shape
  • Asymmetry detection
  • Egger's test results

Additional Plots

  • L'Abbé plots
  • Galbraith plots
  • Influence plots
  • Leave-one-out analyses

Subgroup & Sensitivity Analyses

Subgroup Analysis

Compare effects across:

  • Study characteristics
  • Population subgroups
  • Intervention variations
  • Geographic regions

Sensitivity Analysis

Test robustness by:

  • Excluding high risk of bias studies
  • Using different effect measures
  • Varying statistical models
  • Removing outliers

AI-Powered Features

Intelligent Suggestions

The system recommends:

  • Appropriate effect measures
  • Analysis model selection
  • Potential subgroups to explore
  • Studies flagging for sensitivity analysis

Result Interpretation

Natural language summaries of:

  • Main findings
  • Heterogeneity interpretation
  • Clinical significance
  • Limitations

Export & Integration

Statistical Software

Export to:

  • R (metafor, meta packages)
  • Stata
  • RevMan
  • Comprehensive Meta-Analysis

Publication Formats

Generate:

  • Journal-ready figures
  • Supplementary data files
  • PRISMA flow diagrams

Best Practices

Before Analysis

  • Check data entry accuracy
  • Verify outcome definitions match
  • Consider clinical heterogeneity
  • Plan subgroup analyses a priori

Interpreting Results

  • Don't over-interpret small effects
  • Consider confidence interval width
  • Report heterogeneity transparently
  • Acknowledge limitations
Did this article help?
Still stuck?