The Edinburgh Postnatal Depression Scale (EPDS): translation and validation study of the Iranian version

Abstract

The Edinburgh Postnatal Depression Scale (EPDS) is a widely used instrument to measure postnatal depression. This study aimed to translate and to test the reliability and validity of the EPDS in Iran. The English language version of the EPDS was translated into Persian (Iranian language) and was used in this study. The questionnaire was administered to a consecutive sample of 100 women with normal (n = 50) and caesarean section (n = 50) deliveries at two points in time: 6 to 8 weeks and 12 to 14 weeks after delivery. Statistical analysis was performed to test the reliability and validity of the EPDS. Overall 22% of women at time 1 and 18% at time 2 reported experiencing postpartum depression. In general, the Iranian version of the EPDS was found to be acceptable to almost all women. Cronbach's alpha coefficient (to test reliability) was found to be 0.77 at time 1 and 0.86 at time 2. In addition, test-rest reliability was performed and the intraclass correlation coefficient was found to be 0.80. Validity as performed using known groups comparison showed satisfactory results. The questionnaire discriminated well between sub-groups of women differing in mode of delivery in the expected direction. The factor analysis indicated a three-factor structure that jointly accounted for 58% of the variance. This preliminary validation study of the Iranian version of the EPDS proved that it is an acceptable, reliable and valid measure of postnatal depression. It seems that the EPDS not only measures postpartum depression but also may be measuring something more.