Re: [Gnumed-devel] basic test types

[J Busser]

Maybe I have found what separated us...

We were going on the basis that when a test_org's test_type is first 
imported into the test_type table (<deity> forbid we have to enter 
all these by hand!) , it may as well default its conversion_unit into 
whatever the lab had provided, because there would be no 
other/better/reliable way by which to guess or decide what it should 
be - that is, unless we build an extra reference table in which to 
store the desired conversion_unit per combination of (cod, 
coding_system).

Next, precisely because, as you say,
> for each and every row in test_type that represents the
> same clinical test (eg. various types of blood glucose) the
> conversion_unit should be the *same* !

then an extra user step may have to be taken to make conversion_unit 
the same after an import caused them to be different:

>  > > FK_TEST_ORG/ CONVERSION_UNIT /   CODE  / CODING_SYSTEM / NAME
> >  >    6       /       mmol/L    / 14769-4 / LOINC         / GLUCOSE, FASTING
> >  >    7       /       mg/dL     / 14769-4 / LOINC         / GLUCOSE, FASTING
> >  >    8       /       mg/dL     / 14769-4 / LOINC         / GLUCOSE, FASTING
> >
> >  So here a user would decide "for fk_test_org (lab) 7, code 14769-4,
>  > LOINC" I want that expressed in mmol/L.

above, I did not mean that the actual result being 
transferred/written/imported into test_result needs to have its value 
altered, IMO you would never want to distort the original copy of the 
raw data.

At 9:02 PM +0200 9/30/04, Karsten Hilbert wrote:
>         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> No, I think the purpose of that field still isn't clear. It is
> of no concern what unit the lab actually reports results in.
> It also is of no concern which unit I want to eventually see.

but is not one of the functions of conversion_unit to assign this choice?

Maybe you are just saying that the point is to provide a mechanism by 
which to get the results onto the same scale, (e.g.) feet, even 
though it may be possible to let any user choose later DISPLAY the 
result in (e.g.) cm WITHOUT having to change the conversion_unit?