What are we supposed to get from an abstract? I couldn't read the whole study so all I can say is that the authors are saying that mask ventilation isn't inferior to intubation. Unless someone has passed the pay wall for this journal, no one else can make any coherent statement either. "Not inferior" is being used as a a statistical term here and does not have the same significance as a conversational "just as good".
Abstracts are useless, really.