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| 3 | 2009
Klinisk Biokemi i Norden
The Afinion™ system (Afinion) is intended
for measurements performed by personnel
in primary health care. Afinion is so far
launched with tests for C-reactive protein,
Albumin/Creatinine Ratio and Haemoglobin
A1c (HbA1c). CRP and ACR have not been
evaluated by SKUP. The test menu will be
upgraded when new tests are launched.
The HbA1c test measures on whole blood from a
capillary finger prick or a venous sample. Afinion
is manufactured by Axis-Shield PoC AS, Norway.
The Medinor companies are the agents for the sys-
tem in the Scandinavian countries. Medinor AB in
Sweden ordered this evaluation.
The Afinion system for HbA1c consists of the
Afinion AS 100 Analyzer and the Afinion HbA1c Test
Cartridges. The sampling device, which is a part of
the Test Cartridge, is used to bring the correct sample
volume to the Test Cartridge. Afinion uses boronate
affinity chromatography to separate HbA1c in the
sample. After the addition of the sample to the cart-
ridge and placement of the cartridge in the Analyzer,
the procedure is automatic. The result is displayed on
the screen at the end of the test. The measuring range
is 4,0 to 15,0 HbA1c% (NGSP standardised). The
sample volume is about 1,5 µL blood. Measurement
duration is 3 minutes and 15 seconds.
The evaluation of Afinion HbA1c is a complete
SKUP evaluation. An experienced biomedical scien-
tist in a hospital laboratory carried out measurements
on venous blood samples. Two staff nurses in two
primary care centres carried out measurements on
capillary blood samples.
The comparison method was an accredited High
Performance Liquid Chromatography method using
SKUP evaluation: Afinion™ system for HbA1c
Arne Mårtensson, EQUALIS AB, Uppsala
arne.martensson@equalis.se
an ion exchange column called Mono S supplied by
General Diagnostics. The Mono S measurements were
made in the Department of Clinical Chemistry at
the University Hospital MAS in Malmö, Sweden.
Their method is the Swedish Designated Comparison
Method and their results are regularly compared with
the IFCC Reference Methods.
Results
The HbA1c values in the report are NGSP stan-
dardised.
Imprecision
According to the quality goals set by SKUP, the
imprecision of Afinion should not exceed 4,0% in CV.
The imprecision calculated for venous patient samp-
les measured in the hospital laboratory was 2,2% in
CV. The imprecision calculated for capillary patient
samples measured at the primary care centres was
2,1% in CV. The between-days imprecision calculated
on patient sample results was 1,6% in CV and not
statistically significant different from the within-day
imprecision.
The overall assessment is that the precision of
Afinion was good and fulfilled the quality goal.
Bias
According to the quality goals set by SKUP, the bias of
Afinion should not exceed ±4,0%.
For all capillary sample results together, the Afinion
bias was estimated to be approximately −3,5% and
therefore it fulfilled the quality goals.
In the hospital evaluation Afinion showed both
positive and negative bias depending on the HbA1c
level. The bias could therefore only be assessed at
different levels and a calculated mean bias for all
levels has no meaning. The estimated bias for the low
HbA1c level was nonsignificantly positive and for
the high level it was not significantly negative. The
