Table 4.

Summary of studies with continuous outcomes.

	AAM
Study	A1A1			A1A2+A2A2					P1
	Mean	Std	N	Mean	Std	N	Weight	Hedges' g (95% CI)
McCann et al. (2002)	12.82	1.52	205	12.72	1.76	190	98.56	0.06 (-0.14-0.26)	0.54
Gorai et al. (2003)	14.10	1.30	101	13.66	1.22	249	70.94	0.35 (0.12-0.59)	0.00
Onland-Miret et al. (2005)	13.40	1.50	166	13.63	1.58	207	91.87	-0.15 (-0.35-0.05)	0.15
Small et al. (2005)	12.46	0.22	61	12.16	0.20	103	30.80	1.44 (1.09-1.80)	0.00
Jasienska et al. (2006)	13.10	3.15	21	13.2	1.03	37	13.39	-0.05 (-0.58-0.49)	0.86
Pooled (heterogeneity test: Q = 63.33, P<0.01)
Random effect model			554			786	305.57	0.33 (-0.14-0.80)	0.17
Pooled after excluding Asians and mixed populations: (heterogeneity test: Q = 2.10, P = 0.35)
Fixed effects model			392			434	203.83	-0.041 (-0.18-0.10)	0.56

¹all P values are two-sided.