Study design
RECRUITMENT
The NHSBT Clinical Trials Unit supported the design, data management and analysis of the trial. Historical data spanning a 5-year period for three participating centers showed that the overall rate of DGF in DCD kidney transplants was 50%. This was used as the baseline rate. In a pilot series of kidney transplants from extended criteria donors (ECDs), 18 kidneys undergoing SCS followed by 1 h of NMP were compared to a historical control group of 47 ECD transplants after SCS alone. The DGF rates were 1/18 (6%) in the NMP group compared to 17/47 (36%) in the SCS group. Using a fixed sample size study, with interim analyses after 124 and 248 participants had been enrolled and reached 7 d after transplant, a total of 370 patients receiving a DCD kidney were required to detect a 30% relative reduction in DGF (from 50% to 35%) with a power of 80%, a statistical significance of α = 0.05 and 1:1 allocation. To allow for a study withdrawal rate of 7.5%, a maximum of 400 patients were needed for recruitment. There would be no sample size re-estimation during the trial.