| Methods |
Randomised, controlled trial. Observers ("medical assessors") blinded, but not patients or carers. |
| Participants |
Patients with a history of closed head injury with GCS of < 10 for > 6 hours and < 24 hours. |
| Interventions |
HBOT at 1.5 ATA for 1 hour every 8 eight hours for 2 weeks or until death or waking (average number of treatments = 21). Standard care described as 'intensive neurosurgical care according to a comprehensive protocol' was delivered to both groups. |
| Outcomes |
Favourable functional outcome (GOS 1 or 2), mortality, intra‐cranial pressure and adverse events. |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Method not stated: "random assignment of the patient'. |
| Allocation concealment (selection bias) |
Low risk |
Possible and although not clearly described, consent prior to randomisation: "After eligibility and the GCS score were established, informed consent was obtained. Random assignment of the patient.....then occurred". |
| Blinding (performance bias and detection bias)
All outcomes |
Unclear risk |
Observers were blinded but not carers or patients, main outcomes relatively hard: "Outcome was assessed by blinded independent examiners". |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Secondary interim outcomes had significant losses to follow‐up. Only two control patients were lost to all follow‐up: "Two control patients were lost to follow‐up...therefore the 12‐month outcome analyses are based on ... a total of 166 patients". |
| Selective reporting (reporting bias) |
Low risk |
All flagged outcomes were reported. |
| Other bias |
High risk |
Change in protocol for myringotomy during the course has affected some outcomes (discussed in this review). |
