Creatinin

CAL target

Source: Nordic Trueness Project 2002

Material	Nordic Trueness Project 2002			Reference method, DGKC 1997		NORIP
Material	MEP17-1 transferred value	Standard uncertainty	Median	Value	Standard uncertainty/value	Mean	s/mean	N
CAL	70.6	0.41%		69.6	0.75%	80.78	8.3%	1064
X	73.9	0.40%

Distribution of factors CAL/IMEP17-1 and X/IMEP17-1

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Laboratory means of controls

The mean of control values for each lab are first sorted on method group (or for some components on instrument producer) and then on mean value for CAL. Therefore you will see the black line (CAL) as a smooth increasing line with an abrupt decrease for each method group. The other lines are of course not so smooth. MLH is the mean of HIGH and LOW controls.

Notice that for some components MLH for Vitros is lower than for the other metod groups because Vitros have problems with diluted material (not with the concentrated HIGH!).

If a line goes lower than the Y-scale, it means that that the laboratory has not measured the respective control (for MLH: HIGH and/or LOW is not measured).

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CAL-corrected mean of control values X, P, HIGH (H), LOW(L)

For each method group all corrected values outside method group mean + 2s are discarded before calculation

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Instrument comparisons of mean and standard deviation of CAL stpf_i

Y-axis: Deviation from CAL-target. X-axis: Number of cal values in brackets

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Statistics for intercept/slope-corrected CAL for the method groups

Mean an s calculated on all single results (i.e. there are 721 CAL values for Photometry, Jaffe)

Method group	Mean	s	Min	Max	N
! See comment	84.8	1.9	82	88	10
Photometry, Jaffe	82.3	7.0	60	111	721
Photometry, enzymatic	71.3	5.7	61	85	110
Vitros 250-950	79.6	2.7	74	88	223

Laboratorys mean of CAL relative to "minimum" bias goals...

...expressed as Target value x (1 + 0.375 x CVb) where CVb is total biological variation expressed as a coeffisient of variation (13.6%)

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Method specific %CV (all control values), median, maximum and minimum (no of labs in brackets on X-axis)

Distributions, Roche (Cobas and Hitachi)

Red-women or all

Blue-men

Distributions of reference values for the three method groups

Reference limits at z-score equal to -2 and +2

Number of reference values in brackets

12/5-2003

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Cumulative distributions of reference values

Before and after correction with CAL (updated 2004.02.10)

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Main instrument manufacturers

Updated 2004.02.09

Y-axis: z-score (or standard deviate; i.e. -1.96 represent 2.5% of distribution, 0 represent 50% or median and 1.96 represent 97.5% of distribution)

Number of reference values in distribution is shown in brackets in explanation box (both enzyme and non-enzyme methods).

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Jaffé method group

Updated 19/2-2004

Same plot as above, but now only for Jaffé method group

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Age related reference intervals

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Reference values and - limits (y-axis) against age (x-axis)

Reference limits (red) as proposed by NORIP (see here)

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Country differences

Country mean for Hitachi/Modular instruments

Deviation from all mean ± error (2s/n^½ where s is standard deviation and n is number of data for each country).

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Country reference limits with 90% confidence interval

Partitioning is indicated in the grey rows as Y (yes: <0.9% or >4.1% of subpopulation outside common reference limit), M (moderate: % outside is either in the interval [0.9%,1.8%] or [3.2%, 4.1%]), N (no: % outide is in the interval [1.8%, 3.2%]) as evaluated accoding to Ari Lahti's recommandations (but so far not taken into account).

The conclusions (N, M or Y) for partitioning (grey rows) for "Sum", "F", "M" for each country is relative to respective columns in "All".

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