> Date: Wed, 13 Oct 1999 16:32:01 GMT
> Priority: normal
> Subject: Re: LDH assays - L to P or P to L direction?
> From: "Steve Goodall" <[log in to unmask]>
> To: "Dr. Konrad Chan" <[log in to unmask]>,
> "[log in to unmask]" <[log in to unmask]>
> Reply-to: "Steve Goodall" <[log in to unmask]>
> > 1) Is it justifiable to do such a factoring exercise to satisfy the
> > clinicians?
> Firstly, It causes more trouble than it is worth. Years ago, we had a
> reference range for alkaline phosphatase of 4-13 King Armstrong Units / dL.
> The method was changed, and the results corrected, so many times over
> the years that no-one knew what the origin of the correction factors were,
> let alone the source of the reference range. So we started from scratch,
> reported new "proper" units, derived a new reference range, and a bit of
> hard work on education and communication went a long way, and the
> clinicians understood.
>
> Secondly, how many different methodologies have a linear relationship to
> each other? The same correction factor may not be applicable across the
> whole range of the assay.
>
> Thirdly, (and forgetting the second point) if we reported e.g. multiple of
> median for all assays, we would not need units or conversion factors, and
> the SI unit users could understand the non-SI unit users, and vice-versa.
> Excuse me while I take cover.
>
I can see many advantages in this idea and, after all, it is taken as
given in the maternal serum screening world. However, the main
objection as I see it is that it would lessen, if not obliterate, the
desire to explain, understand and hopefully eradicate between-method
differences in values. Since I spend most of my time on this often
forlorn task, I guess I should emphasise its importance,
> Steve Goodall
>
> Steve Goodall
> Clinical Biochemist
> Clinical Biochemistry & Immunology
> The Leeds Teaching Hospitals
> UK
> [log in to unmask]
>
Andy Ellis
Scheme Manager
UK NEQAS for Peptide Hormones
Tel : +44 (0)131 536 2763
Fax : +44 (0)131 536 2765
Email : [log in to unmask]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|