Review: antenatal screening tools to predict postnatal depression generally have low specificity and sensitivity.

Antenatal screening for postnatal depression: a systematic review. QUESTION: What is the sensitivity and specificity of antenatal screening tools developed to predict depression following childbirth? Design Systematic review. Published studies were eligible if they assessed any antenatal instrument, or combination of instruments, to classify women as " at risk " or " not at risk " of postnatal depression during pregnancy. Pregnant women in any care setting were eligible. Papers in languages other than English or French were excluded. The authors included 16 studies from Australia, Demark, Israel, Portugal, Swe-den, the United Kingdom, and the United States, with almost 23,000 participants. Most comprised a study-specific screening tool. Some of the studies were population-based and others were undertaken in teaching hospitals or among low income groups. One reviewer extracted data on sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios. The Edinburgh Postnatal Depression Scale, standardised diagnostic psychiatric interviews, or both were used to assess outcomes. The timing of antenatal screening varied between studies , ranging from 10–12 weeks gestation to 36 weeks. Screening tools also varied. 11 papers used a study-specific screening test. 7 studies combined a study-specific questionnaire with a common self report measure such as the General Health Questionnaire, the Beck Depression Inventory, or the Edinburgh Postnatal Depression Scale. The proportion of women identified as " at risk " of postnatal depression during pregnancy ranged between 10–67%. The actual prevalence of postnatal depression ranged between 5.5–31.5%. Most of the antenatal tools in this review had low specificity and sensitivity for predicting postnatal depression (see table). Conclusions There is no evidence to support routine administration of the antenatal screening tools assessed in this review. The authors suggest that a number of factors may contribute to the poor sensitivity of antenatal screening tools for postnatal depression, such as excluding predictive factors (personality, abuse history and postnatal events). Range of outcomes in studies of antenatal screening tests for postnatal depression Outcome Range of findings Proportion depressed after birth whose depression had been predicted by antenatal screening (sensitivity) 0.23 to 0.79 Proportion of women predicted to be " at risk " who became depressed after birth (positive predictive value) 0 to 0.56 Proportion not depressed after birth, identified as " not at risk " (specificity) 0.43 to 0.93 Proportion predicted to be " not at risk " after birth who did not become depressed (negative predictive value) …