The use of high-flow nasal cannulae was noninferior to the use of nasal CPAP, with treatment failure occurring in 52 of 152 infants (34.2%) in the nasal-cannulae group and in 39 of 151 infants (25.8%) in the CPAP group (risk difference, 8.4 percentage points; 95% confidence interval, -1.9 to 18.7).