Term
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Definition
- known concentration
- Reference Point
- a.k.a. Calibrator |
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Term
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Definition
- previously assayed many times
- target value and acceptable range is known
- assesses the accuracy and validity
- similar matrix as the patient samples
- 2 levels of controls = the assay was accurate
- Do Not Ever report out of control; CLIA violation
- Batch Assay? = Two controls, each and every run, unless otherwise specified.
- Random Analysis Analyzer? = Instrument examples include Vitros, Hatachi, etc. --Two levels of controls once each day |
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Term
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Definition
pure chance will cause a control to be out of range greater than 2 SD, but less than 3 SD
about 1 out of every 20 runs
4.5% of the time
The chance of random analytical error causing two consecutive controls out, is rare |
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Term
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Definition
Usually represented by 5 or more consecutive values to be on the same side of the mean.
Caused by things that change suddenly. I.e. New spectrophotometer lamp |
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Term
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Definition
5 or more values moving in the same direction.
Something that is changing very gradually i.e. spectrophotometer lamp wearing out |
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Term
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Definition
Accuracy = The ability to get the correct value
Precision = The ability to get the same value |
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Term
| Gaussian (Normal) Distribution |
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Definition
68% within 1 SD (excludes 16% on each side)
95% within 2 SD (excludes 2.5% on each side)
99.7% within 3 SD |
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Term
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Definition
control greater than 3 SD out of range
(Reject run data) |
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Term
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Definition
Two consecutive runs, control greater than 2 SD out of range
(Reject run data) |
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Term
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Definition
Same run; greater than 4 SD (total) among controls (i.e. low control and high control both 2 SD out of range)
(Reject run data) |
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Term
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Definition
Four consecutive runs; control greater than 1 SD out of range (i.e. shift)
(Reject run data) |
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Term
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Definition
Ten consecutive runs; control on the same side of mean (i.e. shift)
(Reject run data; check calibration) |
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Term
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Definition
Mandated by CLIA-88
3 Times a Year
Moderate and High Complexity tests
5 challenges per analyte
Passing score = 80%; if not, send CAP (and CMS) documentation as to why you failed; pass the next two challenge cycles in a row; otherwise, you lose your CLIA License for that analyte
CAP forwards this information of to CMS/CLIA |
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Term
| SDI Standard Deviation Index |
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Definition
(Your Value - Peer Value) / SD of Peer Group
e.g.
Glucose challenge; you got 107 mg/dL; your Peer group got 97 mg/dL; national peer group had a SD of 4.0 mg/dL
(107 - 97) / 4 = 2.5 SDI
A SDI of 2.0 or greater is a strong predictor of a future PT failure |
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Term
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Definition
Must be done annually (CAP requirement)
Documents that each individual can perform the test |
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Term
| Statistical Quality Control |
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Definition
i.e. QC
at least 2 levels of controls per day for linear methods (3 levels for non-linear methods)
Monitors analytical variables, such as reagents, sampler accuracy, instrument function, sampler precision, tech's technique
does not monitor pre- or post- analytical variables (e.g. specimen handling) |
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Term
| Overall Quality Assurance |
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Definition
| Includes QC, but also pre or post variables such as specimen handling, External and Internal PT, Continual Quality Improvement |
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