| Characteristic |
Study |
| Doff et al,16 2010 |
Doff et al,10 2012 |
Doff et al,17 2013 |
| Sequence generation (selection bias) |
Unclear |
Unclear |
Unclear |
| Allocation concealment (selection bias) |
Unclear |
Unclear |
Unclear |
| Blinding of participants and personnel (performance bias) |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
| Blinding of outcome assessment (detection bias) |
Low: one blinded observer performed all tracings |
Unclear: unclear if outcome assessor was blinded |
Low: one blinded observer performed twice all measurements |
| Incomplete outcome data (attrition bias) |
Low: reasons for withdrawals were both reported and balanced across groups |
Low: reasons for withdrawals were both reported and balanced across groups |
Low: reasons for withdrawals were both reported and balanced across groups |
| Selective outcome reporting (reporting bias) |
Low: pre-specified outcomes were reported |
Low: pre-specified outcomes were reported |
Low: pre-specified outcomes were reported |
| Other sources of bias |
High: inter- and intraobserver reliability measurements were not carried out |
Unclear |
Unclear |
| Overall risk of bias |
High |
High |
High |
| Characteristic |
Study |
| Ringqvist et al,14 2003 |
Robertson et al,13 2003 |
Tegelberg et al,15 1999 |
| Sequence generation (selection bias) |
Unclear |
Unclear |
Unclear |
| Allocation concealment (selection bias) |
Unclear |
Unclear |
Unclear |
| Blinding of participants and personnel (performance bias) |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
High: performance bias due to knowledge of the allocated interventions by participants and personnel during the study |
| Blinding of outcome assessment (detection bias) |
Unclear: unclear if outcome assessor was blinded |
Unclear: unclear if outcome assessor was blinded |
Unclear: unclear if outcome assessor was blinded |
| Incomplete outcome data (attrition bias) |
High: large number of patients lost to follow up (33% in MAS group) |
Low: no missing outcome data |
Low: reasons for withdrawals are both reported and balanced across groups |
| Selective outcome reporting (reporting bias) |
Low: pre-specified outcomes were reported |
Low: pre-specified outcomes were reported |
High |
| Other sources of bias |
High: in the experimental (MAS) and control (UPPP) groups, some patients (10% and 27%) received both treatments |
High: no control group |
Unclear |
| Overall risk of bias |
High |
High |
High |
