Читать книгу The Pocket Guide to Critical Appraisal - Iain K. Crombie - Страница 32

Systematic reviews search electronic databases of research studies, such as MEDLINE, EMBASE, and CINAHL, to locate published studies, using carefully chosen combinations of key terms. Papers are carefully screened to identify the relevant ones. The chosen papers are commonly referred to as the primary studies. Key data items, such as effect size, standard deviation, and sample size, are extracted from each study. These data are usually, but not always, combined to provide an overall estimate of effect size using meta‐analysis.