| Methods |
|
| Participants |
|
| Interventions |
|
| Outcomes |
|
| Notes |
See Table 8
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomised by drawing lots in a blinded fashion. |
| Allocation concealment (selection bias) |
Low risk |
Randomised by drawing lots in a blinded fashion. |
| Blinding (performance bias and detection bias)
Subjective outcomes |
High risk |
Patients aware of group allocation. |
| Blinding (performance bias and detection bias)
Objective outcomes |
Low risk |
HR and BP automated measurement with Hewlett‐Packard Component Monitoring System or a DINAMAP. Healthcare staff removing chest tubes were blinded to which tape patients were listening to. |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
4 participants withdrew (reasons and group allocation not described), 3 participants had cancelled surgery, 11 had chest tube removal prior to baseline data collection, 3 participants were suffering from confusion, 9 had an unstable condition preventing chest tube removal, 2 had equipment failure, and one person died. |
| Selective reporting (reporting bias) |
Unclear risk |
Unknown if selective outcome reporting. |
| Protection from contamination? |
Low risk |
Interventions administered on an individual basis. |
