. Author manuscript; available in PMC: 2011 May 1.

Published in final edited form as: Compr Psychiatry. 2010 May–Jun;51(3):236–242. doi: 10.1016/j.comppsych.2009.08.002

Table 3.

K-Means Cluster Analysis Findings for PTSD Participants (n=1176)

PSY 5 Scale	Groups
	Cluster 1 (n=280)	Cluster 2 (n=317)	Cluster 3 (n=579)	F	Contrasts
	Low pathology	Externalizers	Internalizers
AGG	7.19	9.94	8.23	90.71^*	1<2,1<3,2>3
PSY	3.93	8.11	8.93	194.00^*	1<2,1<3
CON	14.84	12.07	16.11	119.12^*	1>2,1<3,2<3
NEN	9.31	17.92	18.36	714.40^*	1<2,1<3,2<3
PEE	18.10	16.37	7.07	1109.60^*	1>2,1>3,2>3

p < .01

Note. For the low pathology group (n = 280), 122 (44%) were from the PTSD clinic sample and 158 (56%) from the VES sample. For the externalizer group (n = 317), 218 (69%) were from the PTSD clinic sample and 99 (31%) were from the VES sample. Finally, for the internalizer group (n=579), 537 (93%) were from the PTSD group and 42 (7%) were from the VES group.