Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Healthcare Genetics

Committee Chair/Advisor

Dr. Sara M. Sarasua

Committee Member

Dr. Luigi Boccuto

Committee Member

Dr. Diana Ivankovic

Committee Member

Dr. Benjamin Kipp


The onset of the COVID-19 pandemic brought about a world in which diagnostic testing for the virus that is responsible for COVID-19, SARS-CoV-2, became commonplace. Diagnostic testing was required for myriad reasons beyond simple diagnosis. We set out to compare SARS-CoV-2 testing methods, see if differences sensitivity correlated to increased positivity, and to evaluate self-collection methods.

In examining the Limit of Detection (LoD) of tests receiving FDA Emergency Use Authorization (EUA), our findings indicated that there were considerable differences in LoD. However, these differences in observed sensitivity were not correlated with the methodologic differences as reported in EUA documentation.

We next looked at nine EUA SARS-CoV-2 tests to see if differences in sensitivity resulted in different positivity rates between tests. We reviewed the results of ~2.9 million samples and noted that the variability in positivity rates was likely due to patient populations, such as presenting to an emergency room (highest observed positivity rate) versus presurgical screening (lowest observed positivity rate).

Finally, we evaluated 10 swab/saliva self-collection devices for their ease of use, comfort level, and DNA recovery. We showed that while DNA recovery was comparable between devices, users preferred direct saliva collection over swab-based devices.

Our study indicates that scientific focus should focus less on overall reported sensitivities/LoD’s and more on the intended patient population targeted for use with the assay/test/device. Moreover, patient perspective matters and sample collection methods must account for user preference.

Author ORCID Identifier



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