Table 2. Comparison of MPS III and Control Group Data on the Children’s Sleep Habits Rating Scale.

	MPS III		Controls
	(n = 8)		(n = 8)
Subscale	Mean	Median	Mean	Median	U	z	r	p
	(SD)	(IQR)	(SD)	(IQR)
Bedtime resistance	9.5 (2.1)	9.5 (5)	6.3 (0.5)	6.0 (1)	62.0	−3.3	0.8	0.001**
Sleep onset delay	2.3 (0.7)	2.0 (1)	1.1 (0.4)	1.0 (0)	57.5	−2.9	0.7	0.006**
Sleep duration	6.1 (1.6)	6.0 (1)	3.0 (0)	3.0 (0)	60.0	−3.3	0.8	0.001**
Sleep anxiety	6.4 (2.7)	5.5 (4)	4.0 (0)	4.0 (0)	56.0	−2.9	0.7	0.007**
Night wakings	5.9 (1.5)	6.5 (2)	3.9 (1)	3.5 (2)	55.0	−2.5	0.6	0.016*
Night behaviours	3.3 (1.3)	3.0 (2)	2.0 (0)	2.0 (0)	56.0	−2.9	0.7	0.007**
Parasomnias	9.8 (1.7)	9.0 (4)	6.4 (0.7)	6.0 (1)	63.0	−3.3	0.8	0.000**
Sleep disordered breathing	4.8 (1.8)	4.0 (3)	3.0 (0)	3.0 (0)	56.0	−2.9	0.7	0.007**
Daytime sleepiness	16.0 (4.1)	14.5 (8)	12.3 (2.1)	12.5 (2)	51.0	−2.0	0.5	0.045*

SD, standard deviation; IQR, interquartile range. Items were grouped into nine subscales. Each item was assigned a score between 1 and 3 and some items were reverse-scored to ensure that a higher score represented poorer sleep.

^* p<.05, **p<.01.