09-16-2020, 02:37 PM
(09-16-2020, 12:30 PM)chrisk Wrote: Positives on the rapid response tests will be confirmed with a PCR test.
The antigen test claims 100% accuracy if it shows a positive result. The only reason for the PCR test would be to make sure health insurance will cover it.
It is the negative tests that need to be confirmed! (As I've said, the only specific numbers I've found indicate 1 in 8 true cases will be judged as a (false) negative.)
I also question the taking of the sample. At least for the sentinel testing at Auburn using the antigen test, the students will take their sample (nasal swab, for theirs) themselves and submit it for testing. There are several pitfalls to that:
1. How does the technique of taking the sample impact the detection of the virus? (I suspect this is the primary reason for false negatives. While using the nasal swab or saliva sample is less technical than the nasopharangyeal swab, I don't know how careful one must be.)
2. How does the handling and delivery of the sample impact the detection of the virus? (If it sits in someone's car for 4 or 12 hours or 2 days, are the results as accurate?)
3. How does one validate that the subject actually tried to take a proper sample? ("We play our rivalry game tomorrow and there will be plenty of pro-scouts on hand. I can't afford to get a positive result." This is a lot easier to fake than a urine test.)
If the teams use a trained nurse to take all the samples, that would be a good sign. (But college teams have had staff break the rules.) Since the sample is taken from the nose and there is no particular privacy issue about faces, a video recording of the team members getting tested would probably remove any further doubt about someone not being sampled.


