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Efficient Sampling of Genetically Encoded Biosensor Design Space Enabled with a Design of Experiments and Automation Workflow

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Method for analyzing left-censored bioassay data in large cohort studies.

Jeri L Anderson¹, A Iulian Apostoaei²

¹Division of Surveillance, Hazard Evaluations and Field Studies (DSHEFS), National Institute for Occupational Safety and Health (NIOSH), Cincinnati, Ohio, USA.

Journal of Exposure Science & Environmental Epidemiology

|May 14, 2015

Summary

This study introduces a new method to handle censored urine uranium data in epidemiological studies. The approach minimizes bias when estimating radioactive material intakes from bioassay results.

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Area of Science:

Occupational Health
Radiological Protection
Epidemiology

Background:

Bioassay data analysis is crucial for epidemiological studies involving radioactive material exposure.
Censored data, including values below detection limits, pose significant challenges for accurate intake estimation.
Existing methods, like least-squares regression, can be biased by censored bioassay results.

Purpose of the Study:

To develop and present a method for imputing censored urine uranium concentration values.
To minimize bias in the estimation of radioactive material intakes from bioassay data.
To provide a practical solution for analyzing large bioassay datasets with censored values.

Main Methods:

Development of an empirically-derived equation for imputing censored urine uranium data.
Application of the imputation method to bioassay datasets containing zero or less-than-detection-limit values.
Utilizing least-squares regression for intake estimation with the proposed imputation technique.

Main Results:

The proposed imputation method effectively handles censored urine uranium concentration results.
The method produces minimal bias in estimated intakes when using least-squares regression.
The approach is suitable for analyzing large cohorts with censored bioassay data.

Conclusions:

The empirically-derived imputation equation offers a reliable solution for censored bioassay data.
This method enhances the accuracy of radioactive material intake estimations in epidemiological studies.
The findings support improved analysis of occupational exposure to radioactive materials.