Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Percentage of studies with stated Risk of Bias in each domain (n = 40)
| Random sequence generation (selection bias) | Allocation concealment (selection bias) | Blinding of participants and personnel bias (performance bias) | Blinding of outcome assessment (detection bias) | Incomplete outcome data (attrition bias) | |
|---|---|---|---|---|---|
| High | 0 % | 15 % | 38 % | 25 % | 33 % |
| Unclear | 28 % | 33 % | 40 % | 40 % | 0 % |
| Low | 73 % | 53 % | 23 % | 35 % | 68 % |
