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
- Formulate the research question (PICO)
- Define inclusion and exclusion criteria
- Search for relevant studies
- Extract data from included studies
- Assess study quality and risk of bias
- Calculate effect sizes and perform statistical analysis
- 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)