Predictive validity of the Postpartum Depression Predictors Inventory-Revised (PDPI-R): A longitudinal study with Portuguese women.

OBJECTIVE: This study examined the predictive validity of the prenatal and postnatal versions of the Postpartum Depression Predictors Inventory-Revised (PDPI-R) in European Portuguese women, considering two gold standards to determine postpartum depression (PPD).

DESIGN: Prospective longitudinal study conducted between November 2015 and September 2017.

SETTING: One public referral maternity hospital in the central region of Portugal.

PARTICIPANTS: A total of 140 Portuguese women participated in the study.

MEASUREMENTS: Participants completed the PDPI-R during the second trimester of pregnancy (T1) and at 6 weeks postpartum (T2). At T2, participants also answered the Edinburgh Postnatal Depression Scale (EPDS). During the fourth month postpartum (T3), women were interviewed with the Structured Clinical Interview for DSM-IV Disorders, and between 6 and 9 months postpartum (T4), they completed the EPDS.

FINDINGS: Rates of clinically significant depressive symptoms (EPDS ≥ 10) were 16.4% (23/140) at T2 and 23.2% (23/99) at T4. Six (4.3%) women met the criteria for a clinical diagnosis of PPD (major depressive episode) at T3. Overall, the postnatal version of the PDPI-R performed better than did the prenatal version (average area under the curve = 82% vs. 71%), but both versions accurately predicted women who developed a clinical diagnosis of PPD, at a cut-off score of 4.5 for the prenatal version (sensitivity = 83.3%; specificity = 85.8%) and 9.5 for the postnatal version (sensitivity = 83.3%; specificity = 94.8%).

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Despite the low prevalence of PPD (albeit consistent with prior estimates of major depression at three months postpartum), this clinical condition has very serious consequences for the mother, the baby and the whole family when present. The PDPI-R is a valid screening tool to estimate the psychosocial risk for developing PPD among Portuguese women and can be used in research (e.g., for cross-cultural comparisons) and clinical practice. The recommended cut-off scores could assist health professionals (namely, midwives) in identifying the women who would benefit from appropriate referrals and/or closer monitoring to prevent them from developing PPD.