Objective measures of sleep in Smith-Magenis syndrome
| Common deletion | Uncommon deletion | |
| Number with finding/total tested1-150 | Number with finding/total tested1-150 | |
| Epworth sleepiness scale (score >10) | 13/21 (62) | 4/5 (80) |
| Total sleep time (<7 hours) | 8/23 (35) | 4/5 (80) |
| Percentage REM sleep | 13/23 (57) | 5/5 (100) |
| Decreased (<18%) | 8/23 (35) | 3/5 (60) |
| Increased (>25%) | 5/23 (22) | 2/5 (40) |
| Spontaneous awakenings (⩾10) | 20/23 (87) | 5/5 (100) |
| Multiple sleep latency test (average latency <10 minutes) | 10/21 (48) | 3/5 (60) |
| 6-Sulphatoxymelatonin (inversion of normal rhythm) | 16/16 (100) | 2/3 (67) |
↵1-150 Percentage given in parentheses.