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Confidence intervals for prevalence estimates from complex surveys with imperfect assays
Damon M Bayer1,2, Michael P Fay1, Barry I Graubard3
1Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA.
New statistical methods accurately estimate disease prevalence in complex surveys with imperfect diagnostic tests. These methods ensure reliable confidence intervals, especially when disease prevalence is low, outperforming existing approaches.
Area of Science:
- Biostatistics
- Epidemiology
- Survey Methodology
Background:
- Estimating disease prevalence with confidence intervals is crucial for public health.
- Existing methods are limited to either complex surveys with perfect assays or simple surveys with imperfect assays.
- A gap exists in methodology for complex surveys involving imperfect diagnostic assays.
Purpose of the Study:
- To develop and evaluate novel statistical methods for estimating disease prevalence in complex surveys with imperfect diagnostic assays.
- To compare the performance of new methods against established techniques under various simulation scenarios.
- To apply the developed methods to real-world epidemiological data.
Main Methods:
- Utilized the melding method to integrate gamma intervals for directly standardized rates.
- Incorporated adjustments for imperfect assays by estimating sensitivity and specificity.
- Conducted simulations to assess method performance, including coverage probabilities.
Main Results:
- One proposed method demonstrated at least nominal coverage across all simulated scenarios.
- The new methods showed superior performance compared to established methods, particularly in low prevalence settings.
- In certain simulations, the developed methods guaranteed coverage, unlike competing approaches with significantly lower coverage.
Conclusions:
- The developed statistical methods effectively address the challenge of estimating disease prevalence in complex surveys with imperfect assays.
- These methods provide more reliable confidence intervals, especially in scenarios with low disease prevalence.
- The approach was successfully applied to a SARS-CoV-2 seroprevalence survey in the US adult population.
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