Table 5.
Type of Study | Number of Studies |
---|---|
Observational study | |
Retrospective cohort | 35 |
Prospective cohort | 29 |
Cohort study | 28 |
Case-control study | 20 |
Cross-sectional study | 7 |
Community survey | 1 |
Time series study | 0 |
Nested case-control study | 0 |
Ecological study | 0 |
Treatment study | |
Randomized controlled trial | 24 |
Nonrandomized trial | 6 |
Nonblind trial | 4 |
Double-blind randomized trial | 2 |
Single-blind randomized trial | 0 |
Adaptive clinical trial | 0 |
Review study | |
Literature review | 15 |
A complete list of the site-specific manuscripts can be found in the Supplemental Digital Content (http://links.lww.com/BCR/A37).