Does postnatal depression screening work? Throwing out the bathwater, keeping the baby

Area of Science:

• Mental Health Research
• Public Health Screening Programs
• Psychometric Validation

Background:

• Low help-seeking rates for Postnatal Depression (PND) necessitate improved diagnostic strategies.
• Population screening offers a potential avenue to increase PND diagnosis and treatment rates.
• The Positive Predictive Value (PPV) of screening tools is crucial for cost-effective implementation.

Purpose of the Study:

• To estimate the Positive Predictive Value (PPV) of the Edinburgh Postnatal Depression Scale (EPDS) for Postnatal Depression (PND).
• To assess the potential of EPDS screening to increase PND case identification within a realistic range of prevalence values.

Main Methods:

• Bayes' Theorem was applied using the best available estimates of PND prevalence.
• The PPV of the EPDS was mapped across a range of realistic prevalence values.
• Analysis was based on limited data from seven comparable validation studies.

Main Results:

• EPDS screening consistently increased identification rates across the studied prevalence range.
• The EPDS identified a screen-positive subgroup with 5-fold to 17-fold higher PND prevalence than the general population.
• A central PPV estimate of 62% was observed at a PND prevalence of 6.8%.

Conclusions:

• While EPDS screening shows promise for increasing PND case identification, high-quality data on prevalence and screening accuracy are needed.
• Screening with instruments like the EPDS can improve identification rates and potentially treatment rates for PND.
• Formal diagnostic procedures following positive screens are essential for clinical utility and cost-effectiveness.