Associations between commonly used patient-reported outcome tools in postpartum depression clinical practice and the Hamilton Rating Scale for Depression

The objective of this study is to explore the associations between the patient-reported Edinburgh Postnatal Depression Scale (EPDS) and Patient Health Questionnaire (PHQ)-9 and clinician-reported 17-item Hamilton Depression Rating Scale (HAMD-17) in order to facilitate clinical decision-making. An integrated efficacy dataset of three randomized placebo-controlled trials (NCT02614547, NCT02942004, and NCT02942017) evaluating brexanolone injection, a neuroactive steroid chemically identical to allopregnanolone, in women with postpartum depression was used for this post hoc analysis. Data were pooled across treatment arms. Associations were assessed at day 30 (end-of-trial follow-up). Pearson correlation assessed the relationship between EPDS and PHQ-9 item and total scores and HAMD-17 total score. Cohen’s kappa assessed agreement of EPDS remission (score < 10) and PHQ-9 remission (score < 5) with HAMD-17 remission (score ≤ 7). Ordinary least squares (OLS) regression models were used to develop equations estimating HAMD-17 total scores from EPDS and PHQ-9 scores, respectively. The total scores showed large correlations (HAMD-17/EPDS: r = 0.71, p < 0.001; HAMD-17/PHQ-9: r = 0.75, p < 0.001). Individual EPDS and PHQ-9 items significantly correlated (r= 0.35 to 0.67, all p < 0.001) with HAMD-17 total score. EPDS had 79% sensitivity and 67% specificity to detect HAMD-17 remission; corresponding estimates for PHQ-9 were 76% and 78%. OLS models yielded the following equations: HAMD-17 total = 2.66 + (EPDS total × 0.87) and HAMD-17 total = 3.99 + (PHQ-9 total × 0.97). There were large and statistically significant associations between patient-reported outcomes (EPDS, PHQ-9) and clinician-reported outcomes (HAMD-17) as clinical improvements were associated with patient-reported symptom improvement. These results provide tools to help translate clinical trial data to clinical practice, thus aiding shared decision-making for this critical population.