Turner et al. (2019) completed a systematic overview of studies related to Apraxia of Speech and evaluated the results of two or more studies to obtain an overall answer.

• A. Systematic literature review
• B. Case control study
• C. Meta-analysis
• D. Cohort study

Answer: (C)

Pooling results from multiple studies to produce a single overall estimate is the central idea here. When a review goes beyond describing individual studies and actually combines their quantitative findings to summarize the collective result, that process is a meta-analysis. Turner et al. are described as evaluating results from two or more studies to arrive at an overall answer, which fits meta-analysis, since it seeks a synthesized effect rather than reporting studies separately.

For contrast, a systematic literature review focuses on systematically collecting and appraising studies, but may not merge their results statistically. Case-control and cohort studies are specific study designs that examine associations or outcomes within defined groups, not a synthesis across multiple studies.