Sample size
In an interim analysis of data from a randomised crossover study on CLAC in ventilated infants born at or above 34 weeks of gestation that was undertaken in our unit, the use of a closed-loop oxygen system was associated with a reduction in the mean FiOAt the request of the Ethics committee, an interim analysis will be carried out after half the sample have been recruited to review if enough data have been gained at that point. The analysis will be performed by an independent researcher not involved in the project to avoid introducing bias to our data. The research team will be blinded to the results of the interim analysis unless there are any significant findings.