Short forms of the postpartum depression screening scale: as accurate as the original form

The aims of the present study were to develop three shorter forms of the Portuguese version of the Postpartum Depression Screening Scale (PDSS) as adapted and translated in Portugal, to analyse their psychometrics and to determine their cut-off points and associated conditional probabilities to screen for perinatal depression according to DSM-IV and ICD-10 criteria. In this study, 441 women in the third trimester of pregnancy and 453 in the third month of postpartum were interviewed for diagnostic purposes according to the Portuguese versions of the Diagnostic Interview for Genetic Studies and the Operational Criteria Checklist for Psychotic Illness. DSM-IV and ICD-10 classifications of depression were our gold standards for caseness. Three different shorter forms of the original Portuguese version of the PDSS were developed on the basis of reliability and factorial analysis. PDSS short versions, composed of seven and 21 (postpartum)/24 (pregnancy) items, presented significant reliability and validity and showed satisfactory combinations of sensitivity and specificity (≅80 %). The short forms of the original Portuguese version of the PDSS are valid alternatives to the 35-item version, given their equally precise screening performances, more concise structures and ease of completion.