Beckman Coulter UniCel DxC 600, Инструкция по эксплуатации

Страница: 426 / 498

A13914AF
12-10
Troubleshooting Calibration and Result Errors
Non-Linear and Multipoint Calibrations
Non-Linear and Multipoint Calibrations
Overview
Non-linear chemistries include drugs and specific protein assays. The calibration curves for non-
linear calibrations are logarithmic or have other non-linear relationships.
Non-linear chemistry calibrations may have single level or multilevel calibrators.
•
Multipoint calibrations are based on a single determination of each calibrator level (five or six
levels). The standard curve is determined by use of one of several non-linear math models.
•
Single point non-linear calibrations are based on one or two levels of calibrators. These
chemistries set calibration based on two to four replicates of each calibrator level.
Failed Multipoint calibration errors will be noted with an (*) at the bottom of the calibration report.
Refer to CHAPTER 1, System Description , Non-Linear Chemistries and Non-Linear Calibration
Formulas for additional information on this subject.
Non-Linear Calibration Checks
Non-linear calibrations have a set of calibration checks specific to non-linear calibrations.
•
The first check determines whether the data is reasonable to attempt the curve fitting.
• The second check determines whether the Multipoint span is within acceptable limits.
The next set of errors are inherent to non-linear curve fitting and may or may not cause calibration
failure. Under certain conditions the curve fitting will produce parameters and curves that may
contain mathematical errors. Typically these errors occur outside of the reagent dynamic range and
have no effect on sample recovery. Math errors may be either overrideable or non-overrideable
depending on the severity of the failure. Math errors are reported as "MATH ERROR #" with the
number associated with a specific error that has occurred.
Multipoint Span
•
The Multipoint Span flag is a measure of sensitivity over the entire standard curve.
•
This is the difference between consecutive calibrator rates or absorbencies. There can be up to
six Multipoint spans for Level 0–1, 1–2, 2–3, 3–4, 4–5, 5–0.
Recovery
The Recovery Flag determines whether recovery errors for each calibration level are too large for a
calibration to be useful. The difference between the recovered concentration and the actual
concentration exceeds specification. This error is overrideable.