Thermo Scientific Phadia 100, User Manual

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Quality Assurance Phadia 100 - User Manual
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Participation in the external quality assessment programs of Quality Club gives
the laboratory management and staff a possibility to compare their
in vitro
test
results with results obtained in other laboratories worldwide.
As there are no established true values for in vitro allergy, asthma and
autoimmunity testing, the common mean values obtained in Quality Club
programs are considered to be the best estimates of true values. Thus, partici-
pation in Quality Club is a tool to monitor the accuracy of the laboratory
measurement process for
in vitro allergy, asthma and autoimmunity testing.
Monthly Report
Every month, Quality Club members assay the serum from one or two of the
vials in the same way as patient samples and send the results, completed on a
Result Card, to Phadia AB, or register through Extranet. The samples should be
put randomly in the assay and analysed according to the normal routine. In
return, the members receive a detailed, confindental report of their performance
and can compare their test with others. The well-documented information helps
them to monitor performance and secure high standards of accuracy and
reliability.
Specific IgE results for each of the three allergens requested per month are
analysed by use of established statistical methods. The results are presented in
histograms with a class interval depending on the concentration level (see
histogram). Results outside ±3.5 SD are summarized in white bars. Results for
EliA Autoimmunity are presented in the same way as Specific IgE.
Results for Total IgE and ECP for each of the two serum samples are put together
using the same statistical methods as for Specific IgE. The results are presented
in a format similar to Specific IgE in order to facilitate the interpretation.
The monthly report is based on a computer analysis of the assay results. These
results are given as concentrations, percent deviation from common means and
deviation scores. In the histograms, the bars containing these laboratory results
are black.
The use of deviation score makes it possible to compare different allergens and
different concentration levels in spite of only single determinations. It provides
a standardized measure of the deviation of a laboratory in relation to the
performance of the group of laboratories. The deviation score is calculated as
shown below.
Example:
Common mean 28.8
Standard deviation 2.52
Lab result 31.32
Deviation score 31.32 - 28.8
2.52
= 1.0