QC evaluation

From: ruth ann croson lowney (rcroson@nybc.org)
Date: Tue Jan 27 1998 - 10:50:40 EST


Sorry it has taken so long to summarize but here it is.

There was considerable variation from the very few reponses I received.
For normals, most were run anywhere from 1 a week to 1 daily. The same was
done using calibrite beads for alignment.  One lab runs Cytorol daily for
normal CD4.

Lab ranges for normals run anywhere from 50, 200 samples to twice yearly,
but generally all agree to mean +/- 2SD.

Antibodies are run against existing lab antibodies and are accepted  at +/-
5% for %+,  mean channel within 10%.

For control cells some run 20 data points over 5 days and calculate +/- 2SD
to establish a lab range for new lots.  Others run 10 data points and
choose +/- 2SD.  No one mentioned using CD Chex normal or low CD4 as
control standards, only Cytotrol was mentioned.

As to LJ data some are examined daily others monthly.  It seems that CAP
labs adhere at least to the monthly review.

I was told to refer to NCCLS and to Donal Murphy and Dr. David Lawrence
from the state.  I did contact them but received no reply.

It appears to me, that there are some but not consistent QC "rules" for
clinical labs.  I feel there should be some kind of standard established
and published to help with this issue.

Thanks to all who responded.

*******************************************************************
Ruth A. Croson-Lowney
Supervisor, Flow Cytometry
New York Blood Center
310 East 67th Street
New York, NY 10021
(212) 570-3341
rcroson@nybc.org



This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:51:43 EST