Risk of bias in included studies
| Risk of bias items | Denton et al15 | Miller et al19 | Lun et al18 | Whittingham et al20 | Clark et al13 | Kowall et al17 | Collins et al14 | Eng and Pierrynowski16 |
|---|---|---|---|---|---|---|---|---|
| Adequate method of randomisation | Y | N | Y | Y | Y | Y | Y | U |
| Treatment allocation concealed | N | U | Y | Y | Y | U | Y | U |
| Patient blinded to intervention | N | N | N | N | N | N | N | N |
| Care provider blinded to intervention | N | N | N | N | N | N | N | N |
| Outcome assessor blinded to intervention | N | N | N | N | N | N | N | N |
| Drop-out rate described and acceptable | N | Y | Y | N | N | N | Y | N |
| Participants analysed in the group to which they were allocated | Y | Y | N | Y | Y | Y | Y | Y |
| Reports free of suggestion of selective outcome reporting | U | U | U | U | U | U | Y | U |
| Groups similar at baseline regarding prognostic indicators | Y | N | Y | Y | Y | N | Y | Y |
| Co-interventions avoided or similar | N | U | U | U | Y | U | Y | U |
| Compliance acceptable in all groups | U | U | Y | U | U | U | Y | U |
| Timing of outcome assessments similar in all groups | N | N | Y | Y | Y | Y | Y | Y |
| Total score | 3 | 2 | 6 | 5 | 6 | 3 | 9 | 3 |
N, no; U, nuclear; Y, yes.