Heras and Faith in the testers
Bill C
http://eurosport.com/home/pages/v4/l0/s18/e9257/sport_lng0_spo18_evt9257_sto793363.shtml
The 'B' test to confirm whether or not four times Tour of Spain winner
Roberto Heras has committed a doping offence will have to be repeated
because of a technical error, sources close to the rider said on
Wednesday.
The director of the laboratory carrying out the test said there had
been a delay in the process.
"The process has not finished, it is long and complicated and we will
have to wait 48 hours more," said Francisco Rodriguez.
I'm pretty cycnical, but I'm betting that if this hadn't been as high
profile as it is, and as closely watched they would've just called it
positive and said "That's that".
The argument was that it was going to be bad for cycling and it's
credibility either way. Well now IMO we have a third option that's
really bad for the credibility of the sport, and we are still waiting
for results, but how much faith is anyone going to have in the testing?
It's getting uglier day by day.
Bill C
Robert Chung
> http://tinyurl.com/9hlbb
>
>
http://eurosport.com/home/pages/v4/l0/s18/e9257/sport_lng0_spo18_evt9257_sto793363.shtml
>
> The 'B' test to confirm whether or not four times Tour of Spain winner
> Roberto Heras has committed a doping offence will have to be repeated
> because of a technical error, sources close to the rider said on
> Wednesday.
The arbitrators in the Hamilton case said that there are no errors in the
test.
--
1154 days until the next inaugural.
Jonathan v.d. Sluis
news:3ujrhjF...@individual.net...
Were they talking about the same test?
Diablo Scott
Hamilton's test is mixed cell population in blood. Heras's test is EPO
in urine. They could hardly be more different.
"El método no vale porque no es preciso ni válido." (The method is not
valid, because it is neither precise nor valid) - The guy can really
turn a phrase.
Robert Chung
Ooops. No. They were talking about the homologous blood doping test.
However, the homologous blood doping test is newer than the EPO test, and
thus has a shorter "history." In that case, the arbitration decision was
that it wasn't even necessary to estimate an error rate.
Jonathan v.d. Sluis
Do you really believe that all tests developed after "the" (I think there
are several) EPO tests are automatically unreliable because not enough time
has passed?
Bill C
Not necessarily, but are you going to argue against the idea that the
longer a test is in use, the better understanding we have of it's
accuracy and thier ability to conduct it properly?
Bill C
Robert Chung
>
> Do you really believe that all tests developed after "the" (I think
> there are several) EPO tests are automatically unreliable because not
> enough time has passed?
Of course not. I believe that all tests, whether they were developed early
or late, should be evaluated for error rate. Do you really believe that
it's unnecessary?
--
1154 days until the nex inaugural.
Jonathan v.d. Sluis
news:1132776552....@g49g2000cwa.googlegroups.com...
I didn't really argue anything, did I?
Jonathan v.d. Sluis
> Jonathan v.d. Sluis wrote:
>>
>> Do you really believe that all tests developed after "the" (I think
>> there are several) EPO tests are automatically unreliable because not
>> enough time has passed?
>
> Of course not. I believe that all tests, whether they were developed early
> or late, should be evaluated for error rate. Do you really believe that
> it's unnecessary?
Where did I say that?
Bill C
Bill C
Bill C
B. Lafferty
WADA labs in Paris and (I think) Switzerland as a safeguard. I don't know
that is being done here.
However, it's unclear to me what the "error" is and who is making the claim
and on what basis. Heras' representatives were there for the test procedure
and would have spotted an improper procedure immediately. Anyway., the
world can only sit tight until Friday. I understand Bush and Cheney are
following this closely as it may be part of an al Q. conspiracy to take down
Armstrong and all former Posties.
matabala
"Bill C" <trito...@verizon.net> wrote in message
news:1132769384.6...@g43g2000cwa.googlegroups.com...
Big $ and politics will out in the end. Vino will still have a home with
Liberty Seguros next season.
Patricio Carlos
doping test has been used in other situations for well over a decade.
Robert Chung
> "Robert Chung" <m...@address.invalid> wrote
>>>
>>
>> Of course not. I believe that all tests, whether they were developed
>> early or late, should be evaluated for error rate. Do you really
>> believe that it's unnecessary?
>
> Where did I say that?
Well, I didn't want to do an exhaustive search, but the very first item
found by the Google Groups search http://tinyurl.com/8mpb3 is a post in
which you claim it unnecessary to evaluate the error rate for the
homologous blood doping test. But perhaps I misunderstood, and you really
do think it's important to know error rates.
--
1153 days until the next inaugural.
b...@mambo.ucolick.org
Robert Chung wrote:
> The arbitrators in the Hamilton case said that there are no errors in the
> test.
They were the best arbitrators we have - borrowed
directly from the Office of the Vice President.
> --
> 1154 days until the next inaugural.
Please don't mention the oft-postponed Hamilton case
and the nominal date of the next inaugural in the same
post. That gives me migraines.
Robert Chung
Have you considered prophylaxis?
Not so btw, Happy Thanksgiving to all.
--
1153.
Donald Munro
> Please don't mention the oft-postponed Hamilton case
> and the nominal date of the next inaugural in the same
> post. That gives me migraines.
Just go to www.livedrunk.com and order some beta blockers.
Robert Chung
> "Robert Chung" <m...@address.invalid> wrote
>>
>> early or late, should be evaluated for error rate. Do you really
>> believe that it's unnecessary?
>
> Where did I say that?
Here, too:
http://groups.google.com/group/rec.bicycles.racing/msg/858efa82060fb6db
Robert Chung
> "Robert Chung" <m...@address.invalid> wrote
>>
>> early or late, should be evaluated for error rate. Do you really
>> believe that it's unnecessary?
>
> Where did I say that?
And here:
http://groups.google.com/group/rec.bicycles.racing/msg/b1c0aeadec54a708
Jonathan v.d. Sluis
I agree with the writers of the report (or rather: they convinced me) that
the homologous blood doping test does not need validation studies.
Where did I say that it's unnecessary that all tests, whether they were
developed early or late, should be evaluated for error rate?
Donald Munro
>> Where did I say that?
Robert Chung wrote:
> Here, too:
> http://groups.google.com/group/rec.bicycles.racing/msg/858efa82060fb6db
http://www.brainyquote.com/quotes/quotes/w/waltwhitma132584.html
Jonathan v.d. Sluis
There is a difference between 'one test' and 'all tests'. Your links do not
provide an answer to my question, but I've repeated it already.
Robert Chung
>
> Where did I say that it's unnecessary that all tests, whether they were
> developed early or late, should be evaluated for error rate?
Well, as I said, I haven't done an exhaustive search but you say that
here:
http://groups.google.com/group/rec.bicycles.racing/msg/858efa82060fb6db
And here:
http://groups.google.com/group/rec.bicycles.racing/msg/b1c0aeadec54a708
And here:
http://groups.google.com/group/rec.bicycles.racing/msg/b0fe37ca2c64aeee
Jonathan v.d. Sluis
Those do not provide an answer. I said that I do not think there is an
evaluation necessary for the test for homologous blood doping, which is
different from saying that it's unnecessary that all tests, whether they
were developed early or late, should be evaluated for error rate. Where did
Robert Chung
> Where
> did I say that it's unnecessary that all tests, whether they were
> developed early or late, should be evaluated for error rate?
here:
Fred Marx
the "uh it's not definative" from Monday? What a serious crock of
shit. Three months to publish erm leak the positive A sample and then
this stupidity of a non definative B ssampole then oh look he's positve
after all. Sucks shit all the way around.
Bill C
don't need to be evaluated." That's some pretty shaky ground. You been
talking with Bush and co. to get some tips on how to evaluate
information?
Bill C
Kyle Legate
being careful in thier interpretation.
Bill C
Kyle you may very well be right, but the way it played out sure as
hell doesn't look good to the public, or generate a lot of faith in the
testing system. If that was the case, they need to be doing some
serious PR work right now, but instead they are blustering.
Bill C
Mad Dog
>Kyle you may very well be right, but the way it played out sure as
>hell doesn't look good to the public, or generate a lot of faith in the
>testing system.
All this talk about faith makes me feel like I'm in a small Southern Baptist
church listening to some preacher tell me I'm goin' ta hell. At least with
religion, I've got a choice to swallow it or turn away. With dope testing,
you're stuck with a political system that has the power. Like it or not, some
of those powerful people were involved in the Armstrong/Equipe fiasco. But in
the Heras case, they appear to have followed protocol to a much higher degree.
Or did they? Is it OK to slow the system down because you're on the verge of
stripping a champion's trophy?
I really don't get too worked up regardless. At this point, I'm just waiting
for it all to shake out so I can hear all the deep and insightful
post-crucifixion interviews. I wonder if I can make up a little plastic cross
with Roberto's likeness nailed to it and sell them in Spain...
>If that was the case, they need to be doing some
>serious PR work right now, but instead they are blustering.
They are blustering because this is politics, not science.
Jonathan v.d. Sluis
Those messages do not say that it's unnecessary that all tests, whether they
were developed early or late, should be evaluated for error rate. I conclude
that you have no argument to back up the statement I ever argued it. It's
rather silly to think that these links provide an answer to my question.
Jonathan v.d. Sluis
I read the report and thought it was convincing.
Bill C
the intel leading up to voting to attack Iraq. Same problem applies
here, you have one group almost totally controlling the information
flow on this testing. So you are convinced by what they gave you?
That's fine, and in the end it'll all come out, but a lot of people who
do this kind of science, and research it, aren't convinced. Without a
solid, freely peer reviewed and verified system I won't be convinced.
As long as the UCI and Wada keep acting like they are hiding something,
I'm going to believe that they are.
Bill C
Bill C
Mad Dog wrote:
> Bill C says...
>
> >Kyle you may very well be right, but the way it played out sure as
> >hell doesn't look good to the public, or generate a lot of faith in the
> >testing system.
>
> All this talk about faith makes me feel like I'm in a small Southern Baptist
> church listening to some preacher tell me I'm goin' ta hell. At least with
> religion, I've got a choice to swallow it or turn away. With dope testing,
> you're stuck with a political system that has the power.
their word, not independently verified and researched results. So all
they can do is try to sell the pig in a barrel sight unseen based on
"believe us".
> I really don't get too worked up regardless. At this point, I'm just waiting
> for it all to shake out so I can hear all the deep and insightful
> post-crucifixion interviews. I wonder if I can make up a little plastic cross
> with Roberto's likeness nailed to it and sell them in Spain...
>
> >If that was the case, they need to be doing some
> >serious PR work right now, but instead they are blustering.
>
> They are blustering because this is politics, not science.
They are denying science in fact by not opening everything up for open
review and research. Must have some Kansas lobbyists helping them
decide on their science policy.
Bill C
Jonathan v.d. Sluis
Well, perhaps the next hearing will prove me wrong. It's not such a big deal
and it doesn't answer my question.
Tom Kunich
news:d2ffa$438a2cc6$57d27841$14...@news.versatel.nl...
>
> Well, perhaps the next hearing will prove me wrong. It's not such a big
> deal and it doesn't answer my question.
The problem is that if the UCI and WADA prefer not to tell anyone what
they're doing then no hearing is going to give anything but propaganda.
Robert Chung
> Those messages do not say that it's unnecessary that all tests, whether
> they were developed early or late, should be evaluated for error rate.
> I conclude that you have no argument to back up the statement I ever
> argued it. It's rather silly to think that these links provide an
> answer to my question.
Oh Jonathan. Grow up.
Jonathan v.d. Sluis
That's saying even less. If you have an argument, say so. If not then take
your own advice.
Robert Chung
Tom Kunich
that DETECTING mixed types of red blood cells is infallible. This
couldn't be further from the truth since there are several reasons that
a test could fail to find different types of blood or identify the same
type as being different.
Also, concerning Pantani - measuring hematocrit is a fairly straight
forward process. You can get reasonably accurate readings with a
microscope and a good eye, but you can use either a centrifuge and
measure or there is presently a portable instrument that will
automatically do what a lab technician used to do which is to actually
could the blood cells in a given volume.
Both the EPO and the homologous transfusion tests require a great deal
of technical knowledge and are complex testing sequences in which very
minor mistakes can effect the results.
So while no one with technical training would confuse the hematocrit
results it is quite easy to do so with the EPO and blood doping tests.
I tend to give weight to the testing bodies but the UCI and WADA have
been doing a number of things that bring their ethics into question -
they have been leaking all sorts of stuff to the media in a rather
blatant attempt to sway public opinion against those wishing to defend
themselves and they have been releasing conifidential information to
the press before those accused have any chance to defend themselves or
in some cases to even find out before it hits the news. This smacks
rather loudly of someone who has only weak positions and who wants to
use the forum of public opinion to stiffle objections from the accused.
Tom Kunich
leaking between mother and fetus. This is an entirely different object
of interest and if there are some false positives it merely makes the
doctors take unneeded precautions.
To imply that because the same sort of test has been used for a long
time to find other results, that it isn't required to be verified for
another type of testing is simply incorrect.
I have rather extensive experience working on the designs of separation
science equipment. Our application groups were never surpised to find
that people of international stature often couldn't follow very simple
instructions on how to perform testing procedures to assure absolute
accuracy. But their written reports would often look very knowledgable.
One of the advantage of a test being in place for many years is that
there is a far greater chance that the technicians involved in the
analysis have worked the bugs out of their processes.
Separation science really is a hard science but unfortunately many
practicing it aren't hard scientists.
Jonathan v.d. Sluis
"Robert Chung" <m...@address.invalid> wrote in message
> Jonathan v.d. Sluis wrote:
>> Where
>> did I say that it's unnecessary that all tests, whether they were
>> developed early or late, should be evaluated for error rate?
>
> here:
> http://groups.google.com/group/rec.bicycles.racing/msg/858efa82060fb6db
>
> And here:
> http://groups.google.com/group/rec.bicycles.racing/msg/b1c0aeadec54a708
Those are about the homologous blood tests only, you're repeating the same
false argument.
>
> And here:
> http://groups.google.com/group/rec.bicycles.racing/msg/b0fe37ca2c64aeee
>
That one doesn't say it's unnecessary that all tests, whether they were
developed early or late, should be evaluated for error rate. You are
repeating the same false argument. I conclude that you are unable to find
any reference where I stated that it's unnecessary that all tests, whether
they were developed early or late, should be evaluated for error rate. Why
do you believe that these references would contain an answer when anyone can
see that they don't?
Patricio Carlos
feto-maternal haemorrhage - although that is the most similar to the
homologous transfusion test.
If someone worked out some useful information was to be gained by
centrifuging blood to calculate the volume of white blood cells - let's
call it a leucocrit - such a test would require minimal validation and
one paper plus a whole lot of experience would be sufficient.
Tom Kunich
news:1133227201.6...@g44g2000cwa.googlegroups.com...
Would you be willing to bet someone else's career on that sort of half-assed
test adoption?
Patricio Carlos
extremely bad on Tyler's part.
But I know it is hard to accept that your hero cheated. So feel free to
disbelieve.
Tom Kunich
Where did you find any circumstantial evidence? Exactly what have you any
real knowledge of?
It would appear that you are ready, willing and quite able to punish someone
else for something you suspect them capable of.
Patricio Carlos
"Wire in the Blood" articles. Surely the heamatocrit of 49.7% makes you
a little suspicious? Especially with the low retic counts.
On top of that, there are:
(1) the accusations from Prentice Steffen
(2) the fact that two homologous transfusion tests since the Vuelta
were negative making the chimera theory much weaker
(3) the fact that the only other positive in all sports combined is his
suddenly improved team mate
(4) this all happened in a team that was suddenly getting much, much
better results
If it looks like a duck, quacks like a duck, walks like a duck ...
Tom Kunich
test over 50%. I've never lived above sea level for any period of time
except when I was in the Air Force and stationed at Denver for a year's
schooling.
I would expect that those with naturally high hematocrits would
gravitate to the higher reaches of athletics. And most of the top
riders try to live at altitude. This suggests that MOST of them would
be able to test over 50% a great deal of the time for completely normal
reasons. And if that's the case, wouldn't you think that team doctors
would continually test them and transfuse water to keep them below the
50% level?
1) "The now former TIAA-CREF team physician Prentice Steffen has
retracted the comments he made recently in L'Equipe concerning Lance
Armstrong and other athletes, and doping."
2) 3) 4) We are discussing Heras are we not?
The fact is that you have suspicions. That's all well and find to have
but unless it is backed up by infallible science suspicions and $4 will
get you a late' at Starbucks in San Francisco.
Patricio Carlos
must have confused me.
Very few people have a hct of ~50%. Even amongst elite athletes.
Serious training (eg >5 hours a day on the bike) will generally lead to
a drop in your hct. Tyler's has previously been in the high 30's - low
40's as you'd expect. Suddenly it's 49.7% with low retics. What does 2
plus 2 equal?
gds
Patricio Carlos wrote:
>
> Very few people have a hct of ~50%. Even amongst elite athletes.
> Serious training (eg >5 hours a day on the bike) will generally lead to
> a drop in your hct. Tyler's has previously been in the high 30's - low
> 40's as you'd expect. Suddenly it's 49.7% with low retics. What does 2
> plus 2 equal?
Just FYI. My hct is ~ 49 and has tested at that level each year for
years. And I am not a elite athlete. I am 60 yo and now purely a
recreational rider. In a discussion with my internist he assured me
that he sees other hct's at this level. He also assures me that if I
were to measured afer a long hard ride that the mild dehydration would
surely drive it above 50.
This says nothing about Heras or anyone else, but it sure mystifies me
why 50 was picked.
Patricio Carlos
that very few people are like you. Having a high natural hct doesn't
make you an elite athlete and not having a high hct doesn't preclude
you from becoming one.
50 would have been picked because it is unusual for anyone (including
elite endurance athletes even with altitude training) to have that
without "assistance". It is not to say it is impossible - as you and
Cunego show - just that is is rare.
William Asher
What would be interesting is for the level to be increased to say 55 and
see if everyone in the peleton starts testing in at 53 rather than 49.
I'm not sure what it would prove, but it would sure stimulate some debate
here. Not that help is required in that department.
--
Bill Asher
Tom Kunich
> The frequent references to Tyler and homologous transfusion testing
> must have confused me.
>
> Very few people have a hct of ~50%. Even amongst elite athletes.
> Serious training (eg >5 hours a day on the bike) will generally lead to
> a drop in your hct.
This is what I'm questioning Carlos. Certainly athletes under stress of
racing and heavy training have a drop in hematocrit but it usually seems to
be connected to an increase in total blood volume. But unstressed I wouldn't
be in the least surprised to see a lot more than half of them with natural
hematocrits in the region of 50%.
> Tyler's has previously been in the high 30's - low
> 40's as you'd expect. Suddenly it's 49.7% with low retics. What does 2
> plus 2 equal?
Again - where do you get those numbers? You're getting them from printed
stories from people who are as likely to write rumors as fact.
Tom Kunich
Acording to Williams Hematology the standard blood hematocrit is 46% with
the NORMAL variances between 42 and 50. Much smaller portions of the
population can have natural hematocrits above or below these expected
limits.
And there are a number of conditions which can cause errors in automated
hematocrit measuring that can cause errors up to 6% or more.
As I noted before, high level endurance training causes the total blood
volume to elevate faster than the erythroytes can be manufactured in the
body. However, this higher blood volume has a total RBC count higher than
the higher measured hematocrit in non-athletes and can deliver more oxygen
and scavenge more waste products from the body (which may be more
important).
Because the largest percentage of liquid loss in dehydration is from the
blood when both hematocrit and total blood volume are high measuring over
the 50% limit would be something that perhaps half or more of the peleton
would do were blood samples taken AFTER a race instead of before.
It is my ASSUMPTION that the UCI has made it so difficult for athletes to
get permission to have hematocrits elevated above 50% that in order to stay
within the rules it is simply easier for team doctors to infuse liquids to
obtain 'legal' hematocrit levels. After all, infusing saline is so common
that there were more than a dozen in the medical examination area of the USA
Junior Road Racing championships race in Texas a number of years back after
a relatively trying test on a hot day that was absolutely NOTHING like a
hard day in the Alps. So I believe that although it isn't talked about much,
saline infusion is common almost to the point of being SOP.
If so you might as well kill two birds with one stone and correct the
hematocrit at the same time.
amit....@gmail.com
Tom Kunich wrote:
> 1) "The now former TIAA-CREF team physician Prentice Steffen has
> retracted the comments he made recently in L'Equipe concerning Lance
> Armstrong and other athletes, and doping."
not exactly. he never retracted his claim that hamilton asked him for
doping products (a comment he made years ago). he only retracted the
comment he made this year which was along the lines "not only bad guys
like armstrong dope, but even nice guys like hamilton do too".
Kyle Legate
> Patricio Carlos wrote:
>
>>Very few people have a hct of ~50%. Even amongst elite athletes.
>>Serious training (eg >5 hours a day on the bike) will generally lead to
>>a drop in your hct. Tyler's has previously been in the high 30's - low
>>40's as you'd expect. Suddenly it's 49.7% with low retics. What does 2
>>plus 2 equal?
>
>
> Just FYI. My hct is ~ 49 and has tested at that level each year for
> years. And I am not a elite athlete. I am 60 yo and now purely a
> recreational rider.
>
Which means that your anecdote about your hematocrit is meaningless. If
you trained >5 hours a day your hematocrit would not be 49.
Michael Press
<Sotjf.2517$YT3...@newsread3.news.pas.earthlink.net>,
"Tom Kunich" <tku...@earthlink.net> wrote:
> "Patricio Carlos" <pg...@hotmail.com> wrote in message
> news:1133394310....@g43g2000cwa.googlegroups.com...
> > Regardless of your & Tom's high natural hct, the normal range is such
> > that very few people are like you. Having a high natural hct doesn't
> > make you an elite athlete and not having a high hct doesn't preclude
> > you from becoming one.
> >
> > 50 would have been picked because it is unusual for anyone (including
> > elite endurance athletes even with altitude training) to have that
> > without "assistance". It is not to say it is impossible - as you and
> > Cunego show - just that is is rare.
>
> Acording to Williams Hematology the standard blood hematocrit is 46% with
> the NORMAL variances between 42 and 50. Much smaller portions of the
> population can have natural hematocrits above or below these expected
> limits.
>
> And there are a number of conditions which can cause errors in automated
> hematocrit measuring that can cause errors up to 6% or more.
Six percent of what?
[...]
--
Michael Press
Mad Dog
>What would be interesting is for the level to be increased to say 55 and
>see if everyone in the peleton starts testing in at 53 rather than 49.
It would be even more fun to see it lowered to 48...
(I'm just trying to tow the company line here)
>I'm not sure what it would prove, but it would sure stimulate some debate
>here. Not that help is required in that department.
Surely you don't define this drivel as debate?
Tom Kunich
>
> Which means that your anecdote about your hematocrit is meaningless. If
> you trained >5 hours a day your hematocrit would not be 49.
On exactly what grounds do you make claims like that?
There are MANY professional bicycle racers who have medical releases to
ride with up to 54%.
I suggest that you ought to remain silent on things you apparently
don't understand.
Tom Kunich
There are conditions which cause the instrument to read up to 6% (in
some cases more) different from the reading. In other words someone
with 50% could read 44% or 56%. Usually the operator is aware of this
sort of thing and can tell the differences between medical conditions
that cause this and mechanical conditions of the tests.
Tom Kunich
Carl Sundquist
"Tom Kunich" <cycl...@yahoo.com> wrote in message
news:1133459971....@g14g2000cwa.googlegroups.com...
"I know it when I see it?"
Carl Sundquist
> Kyle Legate wrote:
>>
>> Which means that your anecdote about your hematocrit is meaningless. If
>> you trained >5 hours a day your hematocrit would not be 49.
>
> On exactly what grounds do you make claims like that?
Do you think your blood volume would be the same as it is now if you trained
to the degree of a pro roadie?
gds
Kyle Legate wrote:
> gds wrote:
>> >
> >
> > Just FYI. My hct is ~ 49 and has tested at that level each year for
> > years. And I am not a elite athlete. I am 60 yo and now purely a
> > recreational rider.
> >
>
> Which means that your anecdote about your hematocrit is meaningless. If
> you trained >5 hours a day your hematocrit would not be 49.
Uhh! But I said wasn't an elite athlete just a rcreational athlete.
That's because I have no talent. But being semi retired I have lots of
time and am pretty fit and often ride or hike for 5+ hours.
Kyle Legate
> news:1133459785.2...@g49g2000cwa.googlegroups.com...
>
>>don't understand.
>>
Tom Kunich
trained to the degree of a pro roadie?"
Yes, given enough time to equilibrate.
Unless you're suggesting that those present riders who bear
certificates from the UCI to permit their hematocrit to be as high as
54% would "naturally" have much higher levels.
Tom Kunich
news:gdIjf.11136$QW2.5927@dukeread08...
Yes but no. You KNOW when you centrifuge the sample about what sort of
reading you're going to get. If the reading from the automatic reader is
somehow significantly different you do further tests to see why that would
be. For instance, one type of blood disease causes the erythrocytes to clump
together which would give a high reading on the automatic reader. Just
looking at it under a microscope would show you the cause of the unexpected
reading.
Tom Kunich
news:1133406479....@g14g2000cwa.googlegroups.com...
I'd be willing to bet that there are a million things that he never
retracted.
Carl Sundquist
"Tom Kunich" <tku...@earthlink.net> wrote in message
>>> We're discussing a reading that comes from an automated instrument.
>>> There are conditions which cause the instrument to read up to 6% (in
>>> some cases more) different from the reading. In other words someone
>>> with 50% could read 44% or 56%. Usually the operator is aware of this
>>> sort of thing and can tell the differences between medical conditions
>>> that cause this and mechanical conditions of the tests.
>>>
>>
>> "I know it when I see it?"
>
> Yes but no. You KNOW when you centrifuge the sample about what sort of
> reading you're going to get. If the reading from the automatic reader is
> somehow significantly different you do further tests to see why that would
> be. For instance, one type of blood disease causes the erythrocytes to
> clump together which would give a high reading on the automatic reader.
> Just looking at it under a microscope would show you the cause of the
> unexpected reading.
>
So in other words, you can get a precise measurement by secondary means if
the crit reads over 50%?
Tom Kunich
I don't understand what you're getting at. The "Gold Standard" in hematocrit
is supposed to be centrifuge. There are problems with that because you have
to put in several "adjustments" that have to do with cells not being able to
knock together close enough to exclude all serum.
But it takes a lot of time and requires a lot of blood. So the machine which
reads by counting the cells in a certain volume optically is used for most
tests. This too has possible problems. There is a third method which had
been used for awhile but I don't know if it is now - that's where the lab
technician squints through a microscope and counts the blood cells in a
certain size field. But the problems in all cases can be countered by the
skill of the operator of the equipment.
So no matter what the test it requires a skilled operator and even then it's
possible to get a bad reading in ALL THREE tests, though it would be
peculiar to get them on the same blood sample.
Donald Munro
>> 1154 days until the next inaugural.
b...@mambo.ucolick.org wrote:
> Please don't mention the oft-postponed Hamilton case
> and the nominal date of the next inaugural in the same
> post. That gives me migraines.