Table 1.

Intent-to-treat data by condition and time

Variable	Baseline				One-Week Posttreatment							d
	Treatment (n= 24)		Control (n= 23)		Treatment (n= 24)		Control (n= 23)		Fixed Effects (F-test)
	M	SE	M	SE	M	SE	M	SE	Time	Group	Interaction
Nights/Week with NM (0-7)	3.24	0.39	2.76	0.40	1.82	0.39	2.56	0.40	7.34**	0.08	4.10*	0.68
NM per Week (0-∞)	3.19	0.57	3.50	0.58	2.85	0.57	3.63	0.59	0.10	0.50	0.49	0.21
NM Severity (0-4)	3.17	0.15	3.07	0.16	2.23	0.16	3.04	0.16	9.28***	4.87*	8.05**	0.87
Panic Sxs Upon Waking (0-14)	6.36	0.59	4.66	0.58	4.67	0.60	5.29	0.59	1.39	0.57	6.57**	0.78
PSQI Sleep Quality (0-21)	13.55	1.02	11.81	1.06	9.03	1.01	11.49	1.07	18.07***	0.07	13.68***	0.92
Hours of Sleep (0-24)	5.68	0.34	6.18	0.34	6.61	0.34	5.94	0.34	3.45	0.04	9.79***	0.68
Fearful of Sleep (0-4)	1.85	0.21	1.20	0.22	0.85	0.21	1.20	0.22	15.33***	0.27	15.33***	0.96
Health Symptoms (0-216)	74.31	6.95	75.84	7.08	67.38	6.97	76.49	7.08	1.92	0.29	2.79	0.22
TSI – Depression (0-24)	12.00	1.28	10.52	1.31	9.17	1.28	10.21	1.31	7.85**	0.02	5.10*	0.37
TSI – Anger/Irritability (0-27)	13.56	1.38	12.41	1.41	11.02	1.38	10.98	1.41	9.27***	0.10	0.72	0.16
TSI – Dissociation (0-27)	10.30	1.25	9.34	1.28	8.51	1.25	8.29	1.28	9.54***	0.11	0.66	0.11
TSI – Tension Reduction (0-24)	5.65	0.81	5.24	0.83	4.19	0.81	5.11	0.83	2.94	0.05	2.05	0.36
CAPS Past Month (0-136)	59.11	5.97	55.36	6.10	43.57	5.97	51.80	6.10	12.92***	0.07	5.08*	0.39

^*p < 0.05.

^**p < 0.01.

^***p < 0.001.

NM, nightmare; Sxs, Symptoms; CAPS, Clinician Administered PTSD Scale; TSI, Trauma Symptom Inventory; PSQI, Pittsburgh Sleep Quality Index.

According to Cohen (1988), d = 0.20 is a small effect, d = 0.50 is a medium effect, d = 0.80 is a large effect.