Table 3

A meta-analytic comparison of psychological treatment of depression in primary care and other settings

	Studies in primary care^a				Studies in other settings

	n	d	95% CI	NNT	n	d	95% CI	Z	Q	I²	NNT	P-value
All studies	20	0.31	0.17 to 0.45	5.75	154	0.75	0.65 to 0.84	15.49	519.52	70.55	2.48	<0.001

Outliers excluded	20	0.31	0.17 to 0.45	5.75	146	0.67	0.58 to 0.75	15.34	388.29	62.66	2.75	<0.001

One effect size per study (highest)	15	0.30	0.13 to 0.48	5.95	99	0.79	0.67 to 0.91	12.59	386.57	74.65	2.36	<0.001

One effect size per study (lowest)	15	0.25	0.09 to 0.41	7.14	99	0.62	0.51 to 0.73	11.38	297.08	67.01	2.96	<0.001

BDI only	14	0.43	0.22 to 0.64	4.20	98	0.80	0.68 to 0.92	12.96	288.16	66.34	2.34	<0.01

HAM-D only	7	0.49	0.30 to 0.68	3.68	50	0.97	0.79 to 1.15	10.77	149.85	67.30	1.97	<0.001

↵a More details about these effect sizes can be found in Table 2. BDI = Beck Depression Inventory. d = standardised mean difference. HAM-D = Hamilton Rating Scale for Depression. I² = indicator of heterogeneity in percentages. NNT = numbers-needed-to-treat. Q = indicator of homogeneity.