Confirmation of an occluded anxiety component within the Edinburgh Postnatal Depression Scale (EPDS) during early pregnancy

The Edinburgh Postnatal Depression Scale (EPDS) is a screening tool for depression that has been used widely postnatally and increasingly antenatally. Recent investigations have suggested that the EPDS may actually be measuring both anxiety and depression in late pregnancy and postnatally. The psychometric properties of the EPDS were evaluated in women at 14 weeks of pregnancy to determine if the tool contained an anxiety sub-scale. Exploratory and confirmatory factor analyses revealed the EPDS to be comprised of distinct and correlated anxiety and depression sub-scales. Consistent with previous investigations that have revealed the EPDS to be bi-dimensional in late pregnancy and post-partum, the current investigation confirmed the bi-dimensional (anxiety and depression) factor structure of the instrument in early pregnancy. Clinicians and clinical researchers who routinely use the EPDS may be reassured regarding the stability of the underlying factor structure of the instrument across the antenatal and perinatal period. Further research may be useful to determine any clinical advantage in isolating anxiety and depression sub-scales for screening purposes