Comparison of the practice of frequent referrers and other neurologists
| Criteria | Top seven NIV referrers (n (%)) | Remaining neurologists (n (%)) | p Value* |
| Spirometry (sitting) at presentation | 7 (100) | 51 (33) | 0.0006 |
| Spirometry (sitting) at every visit | 5 (71) | 23 (15) | 0.0018 |
| SNIP at presentation | 4 (57) | 6 (4) | 0.0002 |
| SNIP at every clinic visit | 2 (28) | 4 (3) | 0.020 |
| ABGs at every visit or if symptomatic | 6 (86) | 37 (24) | 0.0014 |
| Any PFT at presentation | 7 (100) | 52 (34) | 0.0006 |
| Any PFT at every clinic visit | 6 (86) | 24 (16) | 0.0002 |
| Criteria for NIV referral based on symptoms and physiology | 5 (71) | 62 (41) | 0.12 |
| Early intervention | 3 (42) | 14 (9) | 0.025 |
↵* Fisher's exact test (two tailed).
ABG, arterial blood gas; NIV, Non-invasive ventilation; PFT, pulmonary function tests; SNIP, sniff nasal inspiratory pressure.