Human HumaStar 600, User Manual

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HumaStar 600 | User manual
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tion limits or reference class limits and so on are exceeded. Both low and high
limits can be set independently (see chapter 6.2.4 for details).
5.4.4.2 Calculations
For the calibration curve calculation following formulas are available:
Linear
Abs = Ax + B
Multilinear
Cx = C1s+(C2s-C1s)*(Sx-S1s)/(S2s-S1s)
linear interpolation between consecutive standards
Spline
C = a*A3 + b*A2 + c*A + d
where consecutive 3d degree polynomials joining consecutive
data
Sigmoid Abs = L + ((H – L)/(1 + exp(-(Conc – a)/b)))
where H, L , a and b are automatic adjusting parameters
Logit4 Abs = R + (K/(1 + exp(-(a+b*ln(Conc)))))
where K, a,b are automatic adjusting parameters
Logit5 Abs = R + (K/(1 + exp(-(a+b*ln(Conc) + c* Conc))))
where K, a,b,c are automatic adjusting parameters
Calibration fit parameter is shown in all cases.
If curve is forced to pass through zero, functions logit 4 and logit 5 will diverge
because of the logarithm function and will not be shown.
Logit5 requires a minimum of 5 standards; logit4 requires a minimum of 4 stand-
ards; sigmoid and multi linear functions require a minimum of 3 standards.
5.4.5 AUTOMATIC CALIBRATION
It is possible to define for each method, which Calibrator Set will be used in
the next calibration, once the present one is expired, deleted or a lot number
changed. This set can also be “Run in advance” and be ready several hours be-
fore the present calibration expires. Open the
Calibration Menu and select on
the left side the
Automatic Calibration
Submenu.
TABLE 9