I was watching CNN interview a Specialist on the subject, he did not seem to be saying what the Reporter sic wanted him to say. They tried a different Doctor later. Somethings I took away:
A lot of false positives
Different view on the efficacy of the test
Change in readings rather than the readings themseleves is what matters
Not worth it if you have 10 years or less to go, which they also referred to as over 70........