Table 1.
Tabular representation of risk of bias assessment of included studies.
| Author | Ethical Approval | Selection Bias | Performance Bias (Blinding) |
Attrition Bias Incomplete Outcome |
Selective Reporting | |
|---|---|---|---|---|---|---|
| Randomization | Allocation | |||||
| [10] | University Hospital medical ethics committee |
Low | Low | Low | Low | Low |
| [8] | (#NCT00150969 (#ISRCTN61708241) |
Low | Low | Low | Low | Low |
| [9] | NCT00290212 | Low | Low | Low | Low | Low |
| [12] | Low | Low | Unclear | Low | Low | |
| [13] | Ethics committee of the Tsushimi Hospital | Low | Low | Unclear | Low | Low |
| [14] | IRB of Cha Hospital (EKI-GLA-06-32). | Low | Low | Unclear | Low | Low |
| [15] | Ethical Committee of Kakunodate General Hospital |
Low | Low | Unclear | Low | Low |
| [16] | Low | Low | Low | Low | Low | |
| [17] | Ethics Committee of Indonesia University |
Low | Low | Low | Low | Low |
| [18] | Local ethics committees |
Low | Low | Unclear | Low | Low |
| [19] | IRB at Tufts University-New England Medical Center NCT00183001 |
Low | Low | Low | Low | Low |
| [20] | Low | Low | Unclear | Low | Low | |
| [21] | ethics committee of Osaka City University medical school | Unclear | Unclear | Unclear | Unclear | Unclear |
| [22] | Human Subjects Committee at the University of Massachusetts Amherst |
Low | Low | Low | Low | Low |
| [3] | University of Wisconsin Health Sciences Human Subjects Committee |
Low | Low | No | Low | Low |
| [4] | The Tayside Committee on Medical Research Ethics |
Low | Low | Low | Low | Low |
| [23] | University Hospital medical ethics committee | Low | Low | Low | Low | Low |
| [24] | CT00642551 | Low | Low | Low | Low | Low |
| [25] | According to institutional guidelines | Low | Low | Unclear | Low | Low |
| [26] | Approval no. 20180726 | Low | Low | Unclear | Low | Low |