Table 3.

Standard mean differences for studies with a “low risk” of bias and studies with “any risk” of bias within each of the seven risk domains.

	Low risk			Any risk
	EFFECT	95% CI	k	EFFECT	95% CI	k	X2	P
Short term
Selection bias	−0.08	−0.28 to 0.11	7	−0.19	−0.49 to 0.11	10	0.35	0.55
Performance bias	–	–	–	−0.11	−0.28 to 0.07	17	–	–
Treatment fidelity	−0.10	−0.20 to 0.01	4	−0.14	−0.40 to 0.11	13	0.12	0.73
Detection bias	−0.07	−0.27 to 0.13	13	−0.23	−0.59 to 0.13	4	0.58	0.45
Statistical bias	−0.11	−0.52 to 0.29	6	−0.10	−0.28 to 0.07	11	<0.01	0.96
Reporting bias	−0.14	−0.35 to 0.06	15	0.11	−0.11 to 0.33	2	2.66	0.10
Generalisability bias	−0.02	−0.14 to 0.09	8	−0.25	−0.62 to 0.12	9	1.35	0.25