If your fasting test was 166 are you immediatly diagnosed or do you have to do another fasting test?
2 strike count. Down in the ball count but still swinging. You need: fasting sugar of 126 or more or A1c of 6.5 or more or 2 hour fasting glucose test of 200 or more. No high sugar symptoms? You need 2 abnormal tests. If you have 1 abnormal test and 1 normal different test, then you repeat the abnormal test on different day. High fasting sugar &, normal a1c, repeat high fasting sugar is 3rd strike.
Yes. It is best not to relie on only one test to make a diagnosis of a chronic condition. The test should be repeated. There is always the outside possibility that it was an error.