. Author manuscript; available in PMC: 2016 Mar 22.

Published in final edited form as: Psychol Bull. 2007 Nov;133(6):955–975. doi: 10.1037/0033-2909.133.6.955

Table 5.

Duration-Controlled Effects of Intervention Strategies on Retention (Fixed Effects)

	Percentage of strategies
Strategy	High	Low	QR	β	k
Information	.67	.76	32.78^***	−0.02	114
N of sessions				−0.13^***
Motivation	.68	.75	42.19^***	−0.07^**	114
N of sessions				−0.14^**
Behavioral	.75	.68	33.76^***	0.03	114
N of sessions				−0.13^***

Note. Continuous independent variables were analyzed with regression, but scores for median splits are presented for display purposes. QR = homogeneity accounted for by the regression model; β = standardized regression coefficient; k = number of effect sizes in model.

^**

p < .01.

^***

p < .001.