Meta Analysis

Meta-Analysis in Public Health

  • Definition
  • A statistical method that combines results from multiple studies
  • Purpose
  • Synthesize evidence
  • Increase statistical power
  • Resolve controversies or inconsistencies
  • When to Use
  • Multiple studies addressing the same research question
  • Similar study designs, populations, and outcome measures
  • Small sample sizes or inconclusive results in individual studies
  • Advantages
  • Increases statistical power and precision
  • Assesses heterogeneity across studies
  • Identifies gaps in research
  • Provides evidence for policy-making and clinical decision-making
  • Steps
    1. Formulate the research question (PICO)
    1. Define inclusion and exclusion criteria
    1. Search for relevant studies
    1. Extract data from included studies
    1. Assess study quality and risk of bias
    1. Calculate effect sizes and perform statistical analysis
    1. Interpret and report results
  • Statistical Analysis
  • Effect Sizes
  • Odds ratios
  • Risk ratios
  • Mean differences
  • Standardized mean differences (SMDs)
  • Meta-Analytic Models
  • Fixed-effect model
  • Random-effects model
  • Heterogeneity Assessment
  • Q-statistic
  • I² index
  • Subgroup Analysis and Meta-Regression
  • Sensitivity Analysis
  • Publication Bias Assessment
  • Funnel plots
  • Egger's test
  • Trim-and-fill method
  • Software and Tools
  • Comprehensive Meta-Analysis (CMA)
  • Review Manager (RevMan)
  • Stata
  • R
  • Limitations
  • Quality of included studies
  • Heterogeneity across studies
  • Publication bias and selective reporting
  • Combining studies with different designs or populations
  • Reporting Guidelines
  • PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)