Table 3.

Pairwise Variability Comparisons Between Diagnostic Groups Using Bootstrapped 95% Confidence Intervals

Variable	PTSD (n = 40) - PI (n = 25)	PTSD (n = 40) - Control (n = 27)	PI (n = 25) - Control (n = 27)
Night-to-night variability
sTST (m)	[1.08, 56.08]*	[58.69, 112.64]**	[25.10, 78.30]**
sSL (m)	[−11.00, 18.15]	[17.05, 37.60]**	[15.24, 36.36]**
sWASO (m)	[−0.10, 48.66]	[40.02, 78.58]**	[20.27, 44.88]**
sSE (%)	[−0.66, 8.02]	[9.80, 15.52]**	[6.86, 12.31]**
oTSTa (m)	[−15.41, 37.98]	[36.75, 83.40]**	[23.29, 69.10]**
oWASOa (m)	[−13.36, 9.31]	[6.83, 22.44]*	[7.25, 26.33]*
oSEa (%)	[1.86, 11.02]*	[8.32, 16.16]**	[0.97, 9.00]*
Within-group variability
sTST (m)	[2372.35, 9121.30]**	[3040.49, 9424.41]***	[−903.42, 1874.68]
sSL (m)	[−96.55,3182.70]	[623.59, 3786.76]**	[90.09, 1234.10]*
sWASO (m)	[55.02,3171.75]*	[1662.96, 4197.87]***	[361.32, 2272.73]**
sSE (%)	[12.29, 241.15]*	[104.39, 309.54]***	[42.14, 118.36]***
oTSTa (m)	[770.35, 6001.86]*	[2304.29, 6957.69]***	[−25.18, 2514.95]
oWASOa (m)	[−327.67, 636.86]	[−113.74, 730.26]	[−23.33, 330.66]
oSEa (%)	[35.70, 121.34]***	[45.14, 124.28]***	[−14.46, 26.83]

Note. Root mean squared successive difference was used as the index of night-to-night variability. PTSD = posttraumatic stress disorder; PI = primary insomnia; sTST = subjective total sleep time; sSL = subjective sleep latency; sWASO = subjective wake after sleep onset; sSE = subjective sleep efficiency; oTST = objective total sleep time, oWASO = objective wake after sleep onset; oSE = objective sleep efficiency.

^aFor the objective variables, n = 25 for PTSD and control and n = 21 for PI.

^*p < .05

^**p < .01

^***p < .001