. Author manuscript; available in PMC: 2012 Jan 1.

Published in final edited form as: Aggress Violent Behav. 2011 JANUARY-FEBRUARY;16(1):6–19. doi: 10.1016/j.avb.2010.10.001

Table 2.

Weighted Mean Effect Sizes by Outcome and Research Design.

Outcome	K^b	Effect size	SE	95% CI	Fail-safe Ns	I²
Overall
Pre-post^a	19	.54^**	.07	.40–.68	1005	73.88^**
Between group designs	16	.54^**	.11	.33–.76	438	79.00^**
PTSD
Pre-post^a	5	.51	.27	−.01–1.03	48	91.14^**
Between group designs	6	.63^**	.19	.26–1.00	57	64.25^*
Externalizing
Pre-post^a	14	.47^**	.08	.31–.64	304	61.30^**
Between group designs	12	.39^*	.17	.06–.70	60	76.40^**
Internalizing
Pre-post^a	16	.50^**	.06	.39–.61	671	50.99^*
Between group designs	15	.56^**	.12	.33–.80	274	72.31^**

Single-group pretest-posttest designs

Number of studies

p < .05

^**

p < .01