Risk of bias summary (methodological quality) of the randomized controlled trials analysis.
| Study | Adequate Randomization | Adequate Allocation Concealment | Blinding of Assessor | Intention to Treat Analysis |
|---|---|---|---|---|
| Astin 200338 | No | Yes | Yes | No |
| Burckhardt 199439 | No | No | No | No |
| Edinger 200540 | No | No | No | Yes |
| Garcia 200641 | No | No | No | Yes |
| Grossman 200742 | No | No | No | Yes |
| Kashikar-Zuck 200543 | Yes | Yes | Yes | Yes |
| Nicassio 199744 | Yes | No | No | No |
| Redondo 200445 | Yes | No | No | Yes |
| Sephton 200736 | Yes | No | No | Yes |
| Soares 200246 | No | No | No | Yes |
| Thieme 200347 | No | No | No | Yes |
| Thieme 200648 | No | No | No | Yes |
| Vlaeyen 199637 | No | No | No | Yes |
| Wigers 199649 | Yes | No | Yes | No |
No: not performed or not reported (unclear).