Table 1 lists these measures and shows that the majority of studies included widely used measures of depressive symptoms or general measures of emotional well-being. Statistical Analysis Effect sizes were calculated using a computer program, DSTAT [Johnson, 1993] and checked with another computer program, MetaWin [Rosenberg et al., 1999]. Hedges and Olkin’s [1985] d was used as the effect size statistic. It is calculated by subtracting the mean of the control or comparison group from the mean of the experimental or intervention group and dividing by the pooled standard deviation. In keeping with a common practice in meta-analyses, we calculated d based upon posttest means [Hedges and Olkin, 1985]. These are means at posttest and at follow-up. In the event that the groups had substantially different average scores on the dependent measures at pretest, we used an adjustment procedure recommended by Rosenthal [1994], in which change scores are used with adjusted standard deviations.