Prevalence of postpartum depression in Spanish mothers:: comparison of estimation by mean of the structured clinical interview for DSM-IV with the Edinburgh Postnatal Depression Scale

BACKGROUND AND OBJECTIVE: Our objectives were: To estimate the prevalence of postpartum depression (PD) by two evaluation methods: Structured Clinical Interview for DSM-IV (SCID), and self-report Edinburgh Postnatal Depression Scale (EPDS), and to identify the EPDS cut-off to provide an unbiased estimation of PD prevalence. PATIENTS AND METHOD: We report data from all women (n = 1191) attending to postnatal routine checking visits at six weeks postpartum during one year in the Gynaecology and Obstetrics Department of the Hospital Clinic of Barcelona (Spain). A two-stage method was used. In the first stage, all women selected completed the EPDS. In the second stage, all women with an EPDS score greater than or equal to 9 (probable PD cases) and a randomized sample of 16% with a score < 9 were evaluated by a psychiatrist using the SCID interview to establish a psychiatric diagnosis of major and minor depression. 402 postpartum women were offered the SCID interview; 68 of them refused to participate. RESULTS: The prevalence of depression according to the SCID interview was 10.15% (CI 95%, 8.43-11.87). The prevalence of major depression was 3.6% (CI 95%, 2.55-4.67) and it was 6.5% (CI 95%, 5.14-7.95) for minor depression. An EPDS cut-off of 11/12 provided an unbiased estimation of the postpartum depression prevalence rate. CONCLUSIONS: Our results justify the need to use different EPDS cut-offs. A cut-off of 10/11 is effective for identifying the population at risk and a cut-off of 11/12 is useful to estimate the prevalence in epidemiological studies.