Characteristics of Groups According to Time of Confirmed Diagnosis Relative to Initiation of MV^*.

Data are expressed as median (range). * The MV directly associated with the start of HMV † Total cumulative days of pre-HMV admissions divided by age (days) at the start of HMV § Total cumulative days of post-HMV admissions divided by total duration (days) of HMV SMA = spinal muscular atrophy; MV = mechanical ventilation; NMD = neuromuscular disease; CM = congenital myopathy; CMD = congenital muscular dystrophy; HMV = home mechanical ventilation; PICU = pediatric intensive care unit; NIV = noninvasive ventilation; NS = not significant Characteristics of Groups According to Time of Confirmed Diagnosis Relative to Initiation of MV*.