Experimental grouping and treatment
All subjects were randomly divided into 4 groups in equal proportions using a random number generator: (1) OT group (male 21, female 4), NIPPV group (male 23, female 2), IMT group (male 20, female 5) and NIPPV + IMT (male 21, female 4). Randomization was performed using opaque sealed envelopes that were opened during screening visits. All subjects received OT for at least 8 h per day with SPO
Flow chart of the study