Verbruggen says, "6.6% are autologous"

[Robert Chung]

Van Hoorebeeck Bart wrote:
> So, can you like say what all that "means" wrt. the Tyler case ? And
> wrt. the test that nailed him?

WRT the Hamilton case? Not much, though it's interesting that the
empirically observed false positive rate tailed off more slowly than the
theoretical one. However, in the Hamilton case, they used the fact that he
had anomalous values for reticulocytes at the Tour of Romandie as a
post-hoc club (his Hb appeared to be in the normal range--the high OFF-hr
score was due to the reticulocytes). This is odd because, if I understand
it properly, low reticulocytes are a marker for EPO use and Hamilton
wasn't accused of using EPO. He was accused of homologous blood doping.

Unless they were saying he blood-doped with an EPO user's blood.

 

[[email protected]]

Robert Chung wrote:

> WRT the Hamilton case? Not much, though it's interesting that the
> empirically observed false positive rate tailed off more slowly than
the
> theoretical one.

Possibly non-gaussian distributions of the empirical values
(theoretical curve seems to assume normal distributions). Figure 3B
shows, IMO, that the tests can detect the "moderate dosage" case but
cannot detect the "low dosage" case without setting the threshold so
low that there is an unacceptably high false positive rate.

> However, in the Hamilton case, they used the fact that he
> had anomalous values for reticulocytes at the Tour of Romandie as a
> post-hoc club (his Hb appeared to be in the normal range--the high
OFF-hr
> score was due to the reticulocytes). This is odd because, if I
understand
> it properly, low reticulocytes are a marker for EPO use and Hamilton
> wasn't accused of using EPO. He was accused of homologous blood
doping.
>
> Unless they were saying he blood-doped with an EPO user's blood.

His Romandie test at 132.9 nearly got him a two week vacation I think
(probably within the measurement error). This is the OFF-hr test that
might have a 1/1000 false positive, but it gets you a sitdown, not
a suspension. So maybe he decided to straighten up, fly right, and
use something he thought they couldn't detect. It begins to provide
a rational explanation for how he got popped later, even after getting
a warning. I still like the switched blood bags theory as well.

The relevance of the Romandie test to the blood-doping case appears
to be that they are saying they can use anything from an athlete's
history as evidence of ... I don't know, suspicious circumstances,
tendency to dope, bad character. One would like to see the actual
RBC histograms they used to get him to verify that they are above
the noise. I get the sense they are a little frustrated when they
just know someone stinks and are dynamically redefining the criteria,
but are getting cavalier with the no-possibility-of-false-positives
approach - not this time perhaps, but next?
Even a guilty man can be framed.

 

[gym.gravity]

Robert Chung wrote:
> Van Hoorebeeck Bart wrote:
> > So, can you like say what all that "means" wrt. the Tyler case ?
And
> > wrt. the test that nailed him?

>
> Unless they were saying he blood-doped with an EPO user's blood.

Lets say he blood doped-through the summer with his own, EPOed blood.
Say he uses EPO in the spring. How would it look if instead of
diluting his blood with saline, he withdrew 100ml every morning, drank
a glass of orange juice and ate 3 chocolate chip cookies? His blood
would have the anomalous reticulocyte score, but if he re-injected
those samples over a period of weeks later in the year (stored in the
same freezer with Santi Perez and at least one other person's blood)
his blood would look pretty close to normal...wouldn't it? Only about
5% of the total red cells would have been produced during an EPO cycle.