Calculation Of Results; Interpretation Of Results - Siemens ADVIA 2120 Operator's Manual

NOTICE
Any modification of computer disks and/or the programs contained on such disks
can adversely affect the control of instrument performance and thereby invalidate
the results obtained as well as the claims that have been made regarding system
performance.
In no event shall Siemens be liable for errors that are introduced by, or result
from, any modification or alteration of the computer disks and/or the programs
contained on such disks by the user, or for any direct or indirect consequences
resulting from such modification or alteration.

Calculation of Results

The system automatically performs all calculations necessary for obtaining final
results.
Through the use of flagging algorithms, laboratory personnel are alerted to
suspected abnormal conditions. These conditions are indicated by the appropriate
flag (such as *, +, and/or color highlighting). Whenever a flag is triggered, the
user should review the results and take appropriate action.
NOTE:
using 64-bit floating point numbers, IEEE standard, as provided by Intel
processors. The number of significant digits is 14. The system rounds numbers
for display to the specified number of digits in the appropriate unit set. For
example, 4.674999999 becomes 4.67, 4.675 becomes 4.68. This means that
certain things might appear inconsistent, such as the % diff appearing to add up
to 99.9% instead of 100%or the displayed value of derived results such as HCT
not appearing to be correct.
Example:

Interpretation of Results

System operators and laboratory supervisors are responsible for operating and
maintaining Siemens products in accordance with the procedures described in the
applicable Product Labeling (online documentation, package inserts, bulletins),
and for determining that product performance conforms to the applicable claims.
If, under these prescribed conditions of operation and maintenance, an aberrant
or abnormal result, as defined by the laboratory protocol, occurs, laboratory
personnel should first make certain that the system is performing and is being
operated in accordance with the Product Labeling; then follow the laboratory
protocol for advising the clinician of a result that appears to have deviated from
the norms established by the laboratory.
Regulatory Information
The ADVIA 2120/2120i Hematology System performs all calculations
HCT = RBC * MCV / 10.0
5.349 * 86.49 / 10 = 46.2635 is rounded to 46.3.
The system displays the values 5.34 * 86.4 / 10
which equal 46.1.
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