Table 4.

Associations between Sleep Variables Collected at Admission and Clinical Outcome at Discharge, Controlling for Age, Sleep Medication Use, and Program Duration.

	FDI at Discharge				Coping at Discharge				Average Pain at Discharge
Independent Variable	β	t	p	R2	β	t	p	R2	β	t	p	R2
Sleep/wake patterns total score (ASWS)*
Step 1: Outcome at admission	0.25	1.42	.17	.14	0.54	3.24	.003	.28	0.84	8.51	<.001	.72
Age	0.20	1.14	.26		0.000	0.002	.99		−0.14	−1.35	.19
Sleep medication use (Y/N)	−0.22	−1.22	.23		0.03	0.18	.86		−0.002	−0.02	.99
Program duration (in days)	0.21	1.20	.24		−0.09	−0.56	.58		−0.04	−0.34	.74
Step 2: ASWS total score at admission	−0.11	−0.54	.60	.15	−0.03	−0.18	.86	.28	0.05	0.45	.66	.72
Sleep hygiene total score (ASHS)*
Step 1: Outcome at admission	0.25	1.42	.17	.14	0.54	3.24	.003	.28	0.84	8.51	<.001	.72
Age	0.20	1.14	.26		0.000	0.002	.99		−0.14	−1.35	.19
Sleep medication use (Y/N)	−0.22	−1.22	.23		0.03	0.18	.86		−0.002	−0.02	.99
Program duration (in days)	0.21	1.20	.24		−0.09	−0.56	.58		−0.04	−0.34	.74
Step 2: ASHS total score at admission	0.28	1.56	.13	.21	−0.13	−0.78	.44	.30	0.24	2.20	.04	.76
Insomnia symptoms (PISI)*
Step 1: Outcome at admission	0.19	1.05	.30	.05	0.37	2.23	.03	.14	0.61	4.90	<.001	.41
Age	0.17	0.98	.33		−0.14	−0.85	.40		0.21	1.60	.12
Sleep medication use (Y/N)	−0.11	−0.64	.53		0.05	0.29	.78		−0.12	−0.98	.33
Program duration (in days)	0.11	0.66	.51		0.05	0.30	.76		−0.06	−0.42	.68
Step 2: PISI total score at admission	0.06	0.29	.78	.06	0.09	0.53	.60	.14	0.95	0.62	.54	.42
Daytime sleepiness (ESS)*
Step 1: Outcome at admission	0.19	1.05	.30	.05	0.37	2.23	.03	.14	0.61	4.90	<.001	.41
Age	0.17	0.98	.33		−0.14	−0.85	.40		0.21	1.60	.12
Sleep medication use (Y/N)	−0.11	−0.64	.53		0.05	0.29	.78		−0.12	−0.98	.33
Program duration (in days)	0.11	0.66	.51		0.05	0.30	.76		−0.06	−0.42	.68
Step 2: ESS total score at admission	0.08	0.53	.60	.06	−0.16	−1.04	.31	.16	0.08	0.65	.52	.42
Sleep quality (daily diaries)ǂ
Step 1: Outcome at admission	0.19	1.06	.30	.05	0.37	2.26	.03	.14	0.61	4.78	<.001	.41
Age	0.17	1.01	.32		−0.14	−0.84	.41		0.21	1.57	.13
Sleep medication use (Y/N)	−0.09	−0.51	.62		0.04	0.26	.79		−0.13	−0.97	.34
Program duration (in days)	0.06	0.35	.73		0.05	0.30	.77		−0.04	−0.33	.74
Step 2: Sleep Quality at admission	−0.37	−2.22	.03	.16	0.22	1.32	.20	.17	−0.46	−4.02	<.001	.59
Total sleep time (actigraphy)ǂ
Step 1: Outcome at admission	0.21	1.20	.24	.08	0.36	2.26	.03	.13	0.61	4.97	<.001	.42
Age	0.20	1.26	.22		−0.22	−1.37	.18		0.20	1.58	.12
Sleep medication use (Y/N)	−0.13	−0.80	.43		0.09	0.56	.58		−0.12	−0.95	.35
Program duration (in days)	0.14	0.85	.40		−0.04	−0.22	.82		−0.07	−0.51	.61
Step 2: Total sleep time at admission	0.15	0.96	.35	.11	−0.03	−0.16	.87	.13	−0.14	−1.15	.26	.44
WASO (actigraphy)ǂ
Step 1: Outcome at admission	0.21	1.20	.24	.08	0.36	2.26	.03	.13	0.61	4.97	<.001	.42
Age	0.20	1.26	.22		−0.22	−1.37	.18		0.20	1.58	.12
Sleep medication use (Y/N)	−0.13	−0.80	.43		0.09	0.56	.58		−0.12	−0.95	.35
Program duration (in days)	0.14	0.85	.40		−0.04	−0.22	.82		−0.07	−0.51	.61
Step 2: WASO at admission	0.17	1.08	.29	.11	−0.07	−0.47	.64	.14	−0.05	−0.42	.68	.42
Sleep onset variability (actigraphy)ǂ
Step 1: Outcome at admission	0.21	1.20	.24	.08	0.36	2.26	.03	.13	0.61	4.97	<.001	.42
Age	0.20	1.26	.22		−0.22	−1.37	.18		0.20	1.58	.12
Sleep medication use (Y/N)	−0.13	−0.80	.43		0.09	0.56	.58		−0.12	−0.95	.35
Program duration (in days)	0.14	0.85	.40		−0.04	−0.22	.82		−0.07	−0.51	.61
Step 2: Sleep onset var. at admission	−0.11	−0.67	.51	.09	−0.07	−0.43	.67	.14	0.04	0.31	.76	.42
Sleep offset variability (actigraphy)ǂ
Step 1: Outcome at admission	0.21	1.20	.24	.08	0.36	2.26	.03	.13	0.61	4.97	<.001
Age	0.20	1.26	.22		−0.22	−1.37	.18		0.20	1.58	.12
Sleep medication use (Y/N)	−0.13	−0.80	.43		0.09	0.56	.58		−0.12	−0.95	.35
Program duration (in days)	0.14	0.85	.40		−0.04	−0.22	.82		−0.07	−0.51	.61
Step 2: Sleep offset var. at admission	0.08	0.45	.66	.09	−0.03	−0.17	.87	.13	−0.05	−0.35	.73	.42

Note: Bolded results indicate statistical significance at Step 2. All models were run independently using linear regression. Age, sleep medication status (Yes [1]/No [0]), and program duration in days were included as covariates in all models. Unadjusted models are available upon request to the corresponding author.

ASHS, Adolescent sleep hygiene scale; ASWS, Adolescent sleep wake scale; ESS, Epworth sleep scale for children; FDI, Functional disability inventory; NRS, Numeric rating scale; PCQ, Pain coping questionnaire; PISI, Pediatric insomnia severity index; WASO, Wake after sleep onset.

^*Measured at admission

^ǂAveraged over first seven days in program (admission)