Instruction Manual

17
in any of the replicates tested. One of the sputum specimens had invalid results for the internal control in all RT-
PCR reactions (replicates were out of range by about 1 cycle). The invalid sputum sample was noted to be highly
mucopurulent in both the raw and pre-processed states, possibly causing the inhibitory result. Excluding the one
invalid result, the specificity with presumed negative lower respiratory specimens was 100% (29/29, 95%CI 88.1-
100%).
12) Post-CLIA Validation Confirmation with a Public Health RT-PCR
After the assay’s CLIA validation was completed and the clinical laboratory testing service was made commercially
available, Quest Diagnostics sent the first five positive specimens and the first five negative specimens that had
been submitted for clinical testing to a county public health laboratory located in Southern California for confirmation
testing with a CDC-based RT-PCR. The public health laboratory results agreed with the Quest assay results: 100%
(5/5, 95% CI 47.8-100%) agreement with the positives and 100% (5/5, 95% CI 47.8-100%) agreement with
negatives.
13) Comparison with the Prior Version of the Quest SARS-CoV-2 rRT-PCR test (n = 460)
Quest Diagnostics selected a total of 460 de-identified specimens from its clinical laboratory testing runs and
compared the new version of the assay containing N1 and N3 targets (“New RT-PCR”) versus the initial version of
the test containing the N1 and N2 targets (“Comparator RT-PCR”). using the same extracted specimen. For each
specimen, the N1 and N3 targets were performed together in a well, and the N2 target was performed in a separate
well. Of the 460 specimens, the results for the Comparator RT-PCR was 35 detected, 421 undetected, and four
inconclusive. Of the 35 specimens that were detected in the Comparator RT-PCR, the New RT-PCR agreed 100%
(35/35, 95%CI 90.0-100%). Of the 421 specimens that were undetected in the Comparator RT-PCR, the New RT-
PCR agreed 100% (421/421, 95%CI 99.1-100%). Of the four specimens that were inconclusive in the Comparator
RT-PCR, three of the four were detected and one was inconclusive in the New RT-PCR.
Comparison with the Prior Version of the Quest SARS-CoV-2 rRT-PCR test (n = 460)
New RT-PCR
(N1+N3)
Comparator RT-PCR (N1+N2)
Detected
Inconclusive
Not Detected
Detected
35
3
0
Inconclusive
0
1
0
Not Detected
0
0
421
14) Unobserved Self-Collection Validation:
A usability study was conducted to confirm that patients could follow the instructions included in the Quest self-
collection kit to appropriately collect, package, and ship a self-collected nasal specimen to a Quest Diagnostics
laboratory for testing. The study was completed in an actual home-use environment.
After providing informed consent, participants were mailed a Quest self-collection kit, which included the instructions
for use, test requisition form, foam nasal swab, specimen transport tube containing transport media, biohazard bag
containing desiccant, transport box, pre-printed FedEx label and shipping bag. The participants proceeded to collect
a nasal specimen unobserved in their home environment and then shipped the specimens back to Quest laboratory
via FedEx following the instructions on the kit. Participants were also asked to fill out a questionnaire that assessed
their ability to understand the different steps in the instructions for use.
A total of 47 individuals were consented to participate in the study. These participants included individuals representing
varying education levels and age ranges. Of the 47 individuals, 42 returned the kit and questionnaire within the study
window. Of these 42, 95.2% (40/42) returned a specimen that was acceptable for testing according to pre-determined
acceptance criteria. The returned specimens were also tested with a PCR assay detecting the internal house-keeping
gene RNase P. All specimens yielded strong RNase P signals, indicating successful sampling of human biological
material.
15) Shipping Stability Study