Klinisk Biokemi i Norden Nr 3, vol. 29, 2017 - page 32

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Klinisk Biokemi i Norden · 3 2017
Summary of an evaluation organised by SKUP
Grete Monsen
SKUP
Xprecia Stride
TM
Coagulation system
for measurement of PT (INR)
Background
Xprecia StrideTM Coagulation system (Figure 1) is
an in vitro diagnostic device for determination of
prothrombin time, PT (INR), with a modified Quick
method. The product is intended for professional use.
The sample material is fresh capillary whole blood.
The system is produced by Siemens Healthineers. The
system was launched into the Scandinavian market
autumn 2015. The SKUP evaluation was carried out
from December 2015 to March 2016 at the request of
Siemens in Norway.
The aim of the evaluation
The aim of the evaluation was to assess the analytical
quality and user-friendliness of Xprecia Stride, both
when used under optimal conditions by experienced
laboratory personnel and when used under real-life
conditions by the intended users in primary health
care. The analytical results were assessed against pre-
set quality goals.
Materials and methods
Under optimal conditions capillary samples from 101
patients were measured on Xprecia Stride. In each of
two primary health care centres (PHCCs), capillary
samples from 40 patients were measured on Xprecia
Stride. Venous samples from all the patients were
analysed on a comparison method; Owren prothrom-
bin time method implemented on STA-R Evolution
with SPA+ reagent from STAGO. The quality goal
for precision was a repeatability (CV) ≤ 5,0 % and for
accuracy that ≥ 95 % of the results should be within
± 20 % from the results of the comparison method.
The quality goal for the user-friendliness was a total
rating of “satisfactory”.
Results
At PT (INR) level < 2,5 the CV was 4,7 % under
optimal conditions and 4,5 % and 5,5 %, at the two
PHCCs respectively. For PT (INR) results
2,5 the
CV was 5,3 % under optimal conditions and 6,4 %
and 7,1 % at the two PHCCs.
At PT (INR) level < 2,5 a negative bias ((-0,09) –
(-0,17)
INR) between Xprecia Stride and the compa-
rison method was shown both under optimal condi-
tions and at the two PHCCs. At PT (INR) level
2,5
a bias of -0,23 INR was found in one of the PHCCs.
Under optimal conditions 93 % of the results were
within the allowable deviation limits for accuracy
(Figure 2). When handled by the intended users 92
% of the results were within the limits (Figure 3). The
user-friendliness was rated as satisfactory. The
frac-
tion of tests wasted due to technical errors was 0,3 %.
Conclusion
The quality goal for repeatability was not fulfilled.
The quality goal for accuracy was not fulfilled. The
quality goal for user-friendliness was fulfilled.
The complete evaluation report is available at
.
A letter with comments from Siemens
Healthineers is attached to the report.
Figure 1. Xprecia Stride Analyzer
1...,22,23,24,25,26,27,28,29,30,31 33,34,35,36,37,38,39,40,41,42,...44
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