Klinisk Biokemi i Norden Nr 2, vol. 15, 2003 - page 11

11
before sample collection. The sample should be colle-
cted with standard technique from the cubital vein
with as little stasis as possible.
Sample collection
Heparin- and EDTA sample tubes should be mixed by
turning the sample tubes ten times. The sample tubes,
if possible, should be stored in the dark not to influen-
ce bilirubin concentrations.
After sample collection the primary tubes without
addition should be kept at room temperature
1
/
2
- 1
1
/
2
hours before centrifugation and Li-heparin tubes sho-
uld be centrifuged within 15 minutes in room tempe-
rature. The samples should be centrifuged 10 minutes
(minimum 1500g).
The serum samples should be distributed to second-
ary sample tubes within two hours after sample colle-
ction, plasma within half an hour. The samples should
be stored at –80°C within four hours after sample col-
lection.
Analysis
Before analysis the samples should be thawed at room
temperature in the dark for one hour, then mixed by
turning ten times. The measurements should be done
within 4 hours after thawing of samples.
If fresh samples are used for analysis, this should be
done within four hours after sample collection.
Data
Data collected from participating laboratories
Analytical method: Instrument manufacturer, instru-
ment name, method group, method name, unit, slope
and intercept (V s = V i x slope + intercept where V s is
submitted value and Vi is original instrument value).
Reference person data registered on questionnaire:
Person ID, age, gender, height, weight, date of 1. day
of last menstrual period (women), ethnic origin, here-
dity for diabetes, number of years residing in a Nordic
country, chronic disease(s), medication, strenuous
exercise last week, alcohol consumption, habitual smo-
king, number of hours from the last meal, date of blood
sampling, number of total blood donations.
Control analytical data: Control ID, measurement
date, series no, measurement value.
Reference person analytical data: Person ID, measu-
rement date, series no, material (serum or plasma),
material handling (fresh or thawed), measurement
value.
Data base
The data are stored in a MS Access relational data base
at Fürst Medical Laboratory, Oslo and is administered
by Pål Rustad.
102 laboratories have participated resulting in about
200 000 measurement data; about 125 000 reference
values (of which barely half is on thawed serum) from
3036 reference persons and about 75 000 control va-
lues.
Data handling
The enzymes and the non-enzymes are treated diffe-
rently:
Enzymes
Heidi Steensland, and later the Norwegian enzyme
group (see “Evaluation”) have had the responsibility to
select the methods with necessary quality (compatible
to IFCC methods at 37°C). If the laboratory have used
a slope/intercept correction to the submitted data, the
data have been transformed back to original instru-
ment values.
Non-enzymes
For each series the reference values are multiplied with
the factor Target CAL / Mean CAL in that series (or
Target X / Mean X if only X have been used in that
series).
Target values for reference sera
The target values for CAL is established in three diffe-
rent ways depending on component (see table 1):
1. Transferred value from IMEP 17-1 (2) to CAL by The
Nordic Trueness Project, 2002.
2. Reference method values established in 1997 by
DGKC
2
.
3. Median from all laboratories in NORIP (HDL-chole-
sterol and TIBC)
The target value for X is either established as transfer-
red value from IMEP 17-1 in The Nordic Trueness
Project or as transferred value from CAL in NORIP.
Data exclusion
Data have been excluded for different reasons:
| 2 | 2003
Klinisk Biokemi i Norden
(Fortsættes side 14)
2 DGKC: “Deuche Gesellschaft für Klinische Chemie”.
1...,2,3,4,5,6,7,8,9,10 12,13,14,15,16,17,18,19,20,21,...44
Powered by FlippingBook