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Klinisk Biokemi i Norden · 4 2018
Summary of an evaluation
organised by SKUP
Grete Monsen and Marianne Risa, on behalf of SKUP
Accu-Chek Instant
for measurement of glucose
Background
Accu-Chek Instant is an in vitro device for quantita-
tive measurement of glucose (Figure 1). The product
is intended for professional use and for self-testing
by people with diabetes. The sample material is fresh
capillary whole blood. Accu-Chek Instant is produced
by Roche Diabetes Care GmbH and was launched into
the Scandinavian market in May 2018. The SKUP
evaluation was carried out in May and June 2017 at
the request of Roche Diagnostics Scandinavia AB.
The aim of the evaluation
The aim of the evaluation was to assess the analytical
quality and user-friendliness of Accu-Chek Instant,
both when used under optimal conditions by expe-
rienced laboratory personnel and under real-life
conditions by intended users (people with diabetes).
Materials and methods
A total of 90 persons with diabetes signed up for the
evaluation and 88 of them completed. All the parti-
cipants received the device and instructions by mail
and no training was given. They used the device
for approximately two weeks at home, before they
attended an evaluation meeting with SKUP. Fresh
capillary whole blood samples from each participant
were analysed on Accu-Chek Instant under optimal
conditions as well as by the participants. Three lots
of test strips were used. Capillary samples from the
same individuals were analysed on a comparison met-
hod (a glucose hexokinase method for measurement
of glucose in plasma, implemented on Roche Cobas
6000). The analytical results were assessed according
to pre-set quality goals. The quality goal for precision
was a repeatability (CV) ≤5,0 %. The quality goal for
accuracy was set according to the International Orga-
nization for Standardization (ISO) ISO 15197:2013.
This quality goal states that at least 95 % of the indi-
vidual glucose results shall be <±0,83 mmol/L of the
average measured values of the reference measurement
procedure at glucose concentration <5,55 mmol/L or
<±15 % at glucose concentration ≥5,55 mmol/L. The
user-friendliness was assessed using a questionnaire
with three given ratings; satisfactory, intermediate and
unsatisfactory, and the quality goal was a total rating
of “satisfactory”.
Results
The CV achieved under optimal conditions was bet-
ween 1,6 and 2,9 %, depending on the glucose con-
centration level. The intended users achieved a CV
between 2,1 and 5,7 %. The higher imprecision result
(5,7 %) refers to glucose concentrations <7 mmol/L.
There was a bias of (-0,08) – (-0,65) mmol/L between
Accu-Chek Instant and the comparison method, also
depending on the concentration level. Under optimal
conditions, 100 % of the results were within the allowa-
Figure 1.
The Accu-Chek Instant system.
