Identification of depression in women during pregnancy and the early postnatal period using the Whooley questions and the Edinburgh Postnatal Depression Scale : protocol for the Born and Bred in Yorkshire: PeriNatal Depression Diagnostic Accuracy (BaBY PaNDA) study

INTRODUCTION: Perinatal depression is well recognised as a mental health condition but <50% of cases are identified by healthcare professionals in routine clinical practice. The Edinburgh Postnatal Depression Scale (EPDS) is often used to detect symptoms of postnatal depression in maternity and child services. The National Institute for Health and Care Excellence (NICE) recommends 2 'ultra-brief' case-finding questions (the Whooley questions) to aid identification of depression during the perinatal period, but this recommendation was made in the absence of any validation studies in a perinatal population. Limited research exists on the acceptability of these depression case-finding instruments and the cost-effectiveness of routine screening for perinatal depression. METHODS AND ANALYSIS: The diagnostic accuracy of the Whooley questions and the EPDS will be determined against a reference standard (the Client Interview Schedule-Revised) during pregnancy (around 20 weeks) and the early postnatal period (around 3-4 months post partum) in a sample of 379 women. Further outcome measures will assess a range of psychological comorbidities, health-related quality of life and resource utilisation. Women will be followed up 12 months postnatally. The sensitivity, specificity and predictive values of the Whooley questions and the EPDS will be calculated against the reference standard at 20 weeks pregnancy and 3-4 months post partum. Acceptability of the depression case-finding instruments to women and healthcare professionals will involve in-depth qualitative interviews. An existing decision analytic model will be adapted to determine the cost-effectiveness of routine screening for perinatal depression. ETHICS AND DISSEMINATION: This study is considered low risk for participants. Robust protocols will deal with cases where risk of depression, self-harm or suicide is identified. The protocol received favourable ethical opinion from the North East-York Research Ethics Committee (reference: 11/NE/0022). The study findings will be published in peer-reviewed journals and presented at relevant conferences

Identifying perinatal depression with case-finding instruments : a mixed-methods study (BaBY PaNDA – Born and Bred in Yorkshire PeriNatal Depression Diagnostic Accuracy)

Background: Perinatal depression is well recognised as a mental health condition but < 50% of cases are identified in routine practice. A case-finding strategy using the Whooley questions is currently recommended by the National Institute for Health and Care Excellence. Objectives: To determine the diagnostic accuracy, acceptability and cost-effectiveness of the Whooley questions and the Edinburgh Postnatal Depression Scale (EPDS) to identify perinatal depression. Design: A prospective diagnostic accuracy cohort study, with concurrent qualitative and economic evaluations. Setting: Maternity services in England. Participants: A total of 391 pregnant women. Main outcome measures: Women completed the Whooley questions, EPDS and a diagnostic reference standard (Clinical Interview Schedule – Revised) during pregnancy (20 weeks) and postnatally (3–4 months). Qualitative interviews were conducted with health professionals (HPs) and a subsample of women. Results: Diagnostic accuracy results: depression prevalence rates were 10.3% during pregnancy and 10.5% postnatally. The Whooley questions and EPDS (cut-off point of ≥ 10) performed reasonably well, with comparable sensitivity [pregnancy: Whooley questions 85.0%, 95% confidence interval (CI) 70.2% to 94.3%; EPDS 82.5%, 95% CI 67.2% to 92.7%; postnatally: Whooley questions 85.7%, 95% CI 69.7% to 95.2%; EPDS 82.9%, 95% CI 66.4% to 93.4%] and specificity (pregnancy: Whooley questions 83.7%, 95% CI 79.4% to 87.4%; EPDS 86.6%, 95% CI 82.5% to 90.0%; postnatally: Whooley questions 80.6%, 95% CI 75.7% to 84.9%; EPDS 87.6%, 95% CI 83.3% to 91.1%). Diagnostic accuracy of the EPDS (cut-off point of ≥ 13) was poor at both time points (pregnancy: sensitivity 45%, 95% CI 29.3% to 61.5%, and specificity 95.7%, 95% CI 93.0% to 97.6%; postnatally: sensitivity 62.9%, 95% CI 44.9% to 78.5%, and specificity 95.7%, 95% CI 92.7% to 97.7%). Qualitative evaluation: women and HPs were supportive of screening/case-finding for perinatal depression. The EPDS was preferred to the Whooley questions by women and HPs, mainly because of its ‘softer’ wording. Whooley question 1 was thought to be less acceptable, largely because of the terms ‘depressed’ and ‘hopeless’, leading to women not revealing their depressive symptoms. HPs identified a ‘patient-centred’ environment that focused on the mother and baby to promote discussion about mental health. Cost-effectiveness results: screening/case-finding using the Whooley questions or the EPDS alone was not the most cost-effective strategy. A two-stage strategy, ‘Whooley questions followed by the Patient Health Questionnaire’ (a measure assessing depression symptomatology), was the most cost-effective strategy in the range between £20,000 and £30,000 per quality-adjusted life-year in both the prenatal and postnatal decision models. Limitations: Perinatal depression diagnosis was not cross-referenced with women’s medical records so the proportion of new cases identified is unknown. The clinical effectiveness and cost-effectiveness of screening/case-finding strategies was not assessed as part of a randomised controlled trial. Conclusions: The Whooley questions and EPDS had acceptable sensitivity and specificity, but their use in practice might be limited by low predictive value and variation in their acceptability. A two-stage strategy was more cost-effective than single-stage strategies. Neither case-finding instrument met National Screening Committee criteria. Future work: The yield of screening/case-finding should be established with reference to health-care records. The clinical effectiveness and cost-effectiveness of screening/case-finding for perinatal depression needs to be tested in a randomised controlled trial. Funding: The National Institute for Health Research Health Services and Delivery Research programme