Objective To investigate the efficacy of heated humidified high-flow nasal cannula(HHHFNC) and nasal continuous positive airway pressure(nCPAP) in preterm infants aged 26-31~(+6) weeks with respiratory distress syndrome after ventilator weaning.Methods A total of 161 preterm infants were randomly divided into two groups after ventilator weaning:HHHFNC treatment(n=79) and nCPAP treatment(n=82).The two groups were subdivided into26-28~(+6) weeks and 29-31~(+6) weeks groups according to the gestational age.The...