N-SIPPV versus bi-level N-CPAP for early treatment of respiratory distress syndrome in preterm infants

Bi-level CPAP; Nasal synchronized intermittent positive pressure ventilation; Non-invasive ventilation; RDS; Very low birth-weight; Birth Weight; Female; Humans; Infant, Extremely Low Birth Weight; Infant, Newborn; Infant, Premature; Intermittent Positive-Pressure Ventilation; Length of Stay; Male; Noninvasive Ventilation; Respiratory Distress Syndrome, Newborn; Retrospective Studies; Treatment Outcome; Pediatrics, Perinatology and Child Health; Obstetrics and Gynecology