The proportion of patients meeting ETI criteria in the CPAP group was significantly lower compared to those in the control group ( 6/40 = 15 % vs. 26/41 = 63 % , respectively , p < 0.001 ; relative risk 0.24 , 95 % CI 0.11-0 .51 ; number needed to treat , 2 ) two patients were intubated in the CPAP group and one in the control group .