| Study characteristics |
| Methods |
Cluster‐randomised controlled trial comparing simulation‐based team training versus no intervention. |
| Participants |
All employed multi‐professional obstetric staff members of included units: 471 (intervention) versus 503 participants (control). |
| Interventions |
1‐day, simulation‐based obstetric team training in a simulation centre versus no intervention. Training content: crew resource management and medical technical skills (shoulder dystocia, postpartum haemorrhage, umbilical cord prolapse, eclampsia and resuscitation of a pregnant woman). |
| Outcomes |
Teamwork performance and medical technical skills during an unannounced in situ simulation (2 scenarios), assessed 8 months post‐intervention. |
| Notes |
Multicentre trial including 24 hospitals, the Netherlands. Study period: 2009‐2011. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Computerised randomisation (computer‐generated list) by an independent researcher. |
| Allocation concealment (selection bias) |
Low risk |
All cluster were randomised at once by an independent researcher using a computerised, stratified randomisation. |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
Participants were not blinded to the intervention (impossible). Probably low impact on results. |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Assessors (expert panel) were blinded to the study allocation. |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
No withdrawals. Only a few missing data (1/24 video missing from intervention group and 2/24 videos missing from control group), missing data were reported. |
| Selective reporting (reporting bias) |
Low risk |
None not reported outcomes noted. Study protocol available. |
| Other bias |
High risk |
High risk of bias due to clustering effect (has not been taken into account within the analysis). |
