What statistical method combines results across multiple studies addressing the same question?

What statistical method combines results across multiple studies addressing the same question?

• A. Systematic review
• B. Narrative synthesis
• C. Case study synthesis
• D. Meta-analysis

Answer: (D)

When researchers want to combine results from several studies that address the same question, the method used is meta-analysis. It is a statistical approach that pools effect sizes from individual studies to produce an overall estimate. By converting different outcomes to a common metric (like an odds ratio or standardized mean difference) and weighting each study by its precision, meta-analysis yields a single summary statistic with an associated confidence interval. It also assesses whether results are consistent across studies (heterogeneity) and can use fixed-effect or random-effects models to account for variability. This approach is the best fit because it provides a quantitative synthesis and an overall measure of effect and uncertainty, rather than just a narrative summary. Systematic reviews identify, appraise, and summarize evidence and may include meta-analysis, but the statistical pooling itself is what distinguishes meta-analysis. Narrative or case-study syntheses describe findings without combining data into a single numeric estimate.

When researchers want to combine results from several studies that address the same question, the method used is meta-analysis. It is a statistical approach that pools effect sizes from individual studies to produce an overall estimate. By converting different outcomes to a common metric (like an odds ratio or standardized mean difference) and weighting each study by its precision, meta-analysis yields a single summary statistic with an associated confidence interval. It also assesses whether results are consistent across studies (heterogeneity) and can use fixed-effect or random-effects models to account for variability. This approach is the best fit because it provides a quantitative synthesis and an overall measure of effect and uncertainty, rather than just a narrative summary. Systematic reviews identify, appraise, and summarize evidence and may include meta-analysis, but the statistical pooling itself is what distinguishes meta-analysis. Narrative or case-study syntheses describe findings without combining data into a single numeric estimate.