FIGURE 3.

Mean differences in depressive symptoms between prespecified subgroups, according to treatment group, in patients assigned to n−3 fatty acid supplementation groups compared with placebo. The horizontal bars represent SEs, and the vertical gray dotted lines indicate no mean difference. The size of the boxes is proportional to the number of patients. P values for the difference between the groups assigned to n−3 fatty acids compared with placebo are shown. GDS-15 scores were log-transformed because of their positively skewed distribution, and standardized scores were used in the analysis. The mean difference indicates the mean number of SDs in the GDS-15 score (ie, standardized z scores) by which the n–3 fatty acid–treated group was lower or higher than the placebo group at 40-mo follow-up. ALA, α-linolenic acid; GDS-15, 15-item Geriatric Depression Scale.