Table 1

Risk of bias in included studies

Risk of bias itemsDenton et al15Miller et al19Lun et al18Whittingham et al20Clark et al13Kowall et al17Collins et al14Eng and Pierrynowski16
Adequate method of randomisationYNYYYYYU
Treatment allocation concealedNUYYYUYU
Patient blinded to interventionNNNNNNNN
Care provider blinded to interventionNNNNNNNN
Outcome assessor blinded to interventionNNNNNNNN
Drop-out rate described and acceptableNYYNNNYN
Participants analysed in the group to which they were allocatedYYNYYYYY
Reports free of suggestion of selective outcome reportingUUUUUUYU
Groups similar at baseline regarding prognostic indicatorsYNYYYNYY
Co-interventions avoided or similarNUUUYUYU
Compliance acceptable in all groupsUUYUUUYU
Timing of outcome assessments similar in all groupsNNYYYYYY
Total score32656393
  • N, no; U, nuclear; Y, yes.