mertdawg there are lots of things you obviously do not understand. First of all you should not be poking your child to satisfy your curiosities. Why would you ever, ever, do another fingerstick 20 minutes after a prebolus? Second, for as smart and learned as you are, i mean you have read thousands of pages by your own admission about t1d, you would think by now that you would know that if your child has a reading of 100, the actual number is somewhere between 80 and 120, and that assumes perfectly clean fingers and no screwups on your part doing the test. Strips are +/- 20% in that range. they tighten up the tolerance at 70 and below, but your question belies a fundamental ignorance on how accurate the tools we have actually are. so really, and this will sound harsh, stop experimenting on your child and perhaps bring yourself to read practical books on the management of t1d in children.