. Author manuscript; available in PMC: 2012 Feb 21.

Published in final edited form as: Am J Intellect Dev Disabil. 2011 Mar;116(2):142–152. doi: 10.1352/1944-7558-116.2.142

TABLE 5.

Measures of Variability in Sleep Behaviors Across Diagnostic Groups

Estimated Standard Deviations
Source of Variability	Bedtime	Sleep Onset Latency	Sleep Efficiency	24-Hr Sleep
Between-child^a
AUT	1:01	0.35^c	13.26	0:33
DD	0:49	0.35^c	13.77	0:33
TYP	0:41	0.17^c	7.32	0:25
Within-child^b
AUT	1:23	1.01^c	51.04	1:26
DD	1:24	0.95^c	44.89	1:36
TYP	1:11	0.91^c	25.07	1:07

Note. Sleep Onset Latency time was log-transformed to normalize distribution of scores; AUT = autism; DD = developmental delay without AUT; TYP = typically developing.

Standard deviations capture the degree to which each child’s individual mean deviates from their diagnostic group mean.

Standard deviations capture the degree to which the child’s actigraph measures, taken on a particular night, vary from the child’s overall mean.

Standard deviations not significantly different across diagnosis groups.