To the Editor: In their randomized controlled trial, Dr Makrides and colleagues1 found that prenatal supplementation with docosahexaenoic acid (DHA) compared with placebo did not lower levels of postpartum depression (adjusted relative risk [RR], 0.85; 95% confidence interval [CI], 0.70-1.02; P = .09). Depression was defined as a score of greater than 12 on the Edinburgh Postnatal Depression Scale (EPDS), which has a possible score range of 0 to 30 with higher scores indicating more severity. However, it is important to examine between-group differences in the actual score in the EPDS as a continuous rather than dichotomous variable.
Suzuki T. Maternal Depression and Child Development After Prenatal DHA Supplementation. JAMA. 2011;305(4):359-361. doi:10.1001/jama.2011.17