Table 2.

Characteristics of the Polysomnography (PSG) for children with HP and controls.

	Controls		HP		p-Value
	n = 25		n = 33
		missing		missing
	median [min–max]		median [min–max]
Total sleep period (TSP), min	564 [395–671]	0	541 [479–633]	1	0.56
Total sleep time (TST), min	528 [348–655]	0	522 [349–623]	0	0.57
Sleep efficiency, %	95.7 [82.7–98]	0	96 [68–98.7]	1	0.57
Sleep latency, min	16 [6–61]	0	22 [6–103]	2	0.57
REM latency, min	148 [50–243]	0	143 [56–209]	0	0.51
N1, min	58 [27–168]	0	54 [23–93]	1	0.09
N1, %	12.1 [5.1–30.8]	0	10.1 [4.4–18.1]	1	0.05
N2, min	256 [140–299]	0	234 [137–333]	1	0.26
N2, %	45.5 [30.1–57.4]	0	43.8 [19.4–56.9]	1	0.36
N3, min	115 [73–149]	0	111 [65–151]	0	0.69
N3, %	22 [13.3–35.3]	0	21.3 [12.1–29]	0	0.81
REM sleep, min	100 [62–143]	0	124 [64–225]	0	0.009
REM sleep, %	17.7 [12.3–25.2]	0	23.1 [17–36.2]	0	<0.001
WASO	22 [9–88]	0	21.5 [7–118]	1	0.58
Fragmentation index/h	10.3 [2.1–17.7]	0	11.9 [6.3–18.4]	1	0.22
Arousal index/h	8.7 [4.8–14.8]	0	9.3 [4.6–15.7]	1	0.82
Number of cycles	5 [3–6]	0	5 [4–6]	1	0.56
Mean cycle duration, min	105 [81–126]	1	98 [77–131]	5	0.27

HP: high potential; N1: stage 1; N2: stage 2; N3: stage 3; REM: rapid eyes movements; WASO: wake after sleep onset; h: hour; min: minutes.