Due to its history of false positives, especially among older female athletes, the (T/E) ratio test has since been revised and laboratories now also run a carbon isotope ratio test (CIR) if the ratio is unusually high.
If you look at the annotated link , nowhere does it say that there was a history of false positives, only that the carbon isotope ratio test is more accurate hence the 4:1 ratio as compared to the old 6:1 ratio.[/quote]
Also found this:
The Tribunal noted that the IAAF had established that both of Slaney's specimens had been analyzed as having T/E ratios significantly higher than 6:1. The tribunal also observed that Slaney's longitudinal study revealed a previous T/E ratio high of 3:1; meaning that her present ratio, by the most modest of calculations, was more than three times greater than she had ever previously tested.
How many female athletes are on the pill, probably more than half and they were not all failing tests
As for Rupp his mile time is reasonably in line with his 5km/10km time although you could argue he was more of a distance type