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Volume 7: No. 6, November 2010

SYSTEMATIC REVIEW
Quality of Systematic Reviews of Observational Nontherapeutic Studies

This flow chart shows 3 boxes. The top box reads

Total references — 1,053

• Medline via PubMed — 904
• Related publications — 14
• WorldCat — 2
• Scirus — 28
• Manual search — 70
• Guidelines, textbooks, consensus statements — 23
• Published by the authors — 11
• Cochrane Library — 1

It is connected by a vertical line to 2 additional boxes. The left box reads

Included studies — 397

• Systematic reviews for the present article — 145
• Tools (scales and checklists) — 96
• Working groups — 13
• Methodologic studies about bias in observational research — 143

The right box reads

Excluded studies — 656

• Ethical guidelines — 3
• Reviews — 23
• Centers for Disease Control and Prevention study — 4
• Related to interventions — 209
• Related to diagnostic studies — 54
• Not relevant to research questions — 363

Figure. Study flow to identify systematic reviews of observational studies, scales and checklists for planned, formal internal quality evaluation, and studies about bias in observational research.

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The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.  Home  Privacy Policy | Accessibility CDC Home | Search | Health Topics A-Z This page last reviewed October 25, 2011 Centers for Disease Control and Prevention National Center for Chronic Disease Prevention and Health Promotion United States Department of Health and Human Services