Table 2

An illustrative excerpt of all Deming fits containing the data of some clinical chemistry and immunology analytes.

Analysis

11:22

11 - 15:10

11 - 15:7

11 - 10:7

22 - 15:10

22 - 15:7

22 - 10:7


Bias

Const.

Prop.

Bias

Const.

Prop.

Bias

Const.

Prop.

Bias

Const.

Prop.

Bias

Const.

Prop.

Bias

Const.

Prop.

Bias

Const.

Prop.


95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI

95% CI


Alb

-1.81

1.06

-1.86

1.06

-1.05

1.03

0.76

0.98

-0.16

1.01

0.25

0.99

0.40

0.99


Alb

-4.33 to 0.71

0.99 to 1.13

-4.52 to 0.79

0.98 to 1.13

-2.55 to 0.45

0.99 to 1.07

-1.90 to 3.41

0.90 to 1.05

-2.54 to 2.23

0.94 to 1.07

-1.85 to 2.34

0.94 to 1.05

-1.83 to 2.63

0.93 to 1.04


Bili-T

-0.08

1.01

-0.15

1.03

0.10

1.00

0.24

0.96

-0.04

1.01

-0.11

1.03

-0.06

1.02


Bili-T

-0.18 to 0.01

0.99 to 1.02

-0.44 to 0.15

1.00 to 1.06

-0.18 to 0.38

0.96 to 1.03

0.04 to 0.44

0.94 to 0.99

-0.39 to 0.31

0.97 to 1.05

-0.52 to 0.29

0.99 to 1.07

-0.45 to 0.32

0.98 to 1.07


Ca

-0.05

1.03

-0.17

1.08

-0.18

1.08

-0.01

1.00

-0.09

1.04

-0.05

1.02

0.02

0.99


Ca

-0.15 to 0.04

0.99 to 1.07

-0.35 to 0.02

0.99 to 1.16

-0.33 to -0.02

1.01 to 1.15

-0.13 to 0.11

0.95 to 1.05

-0.24 to 0.05

0.98 to 1.10

-0.20 to 0.09

0.96 to 1.09

-0.12 to 0.16

0.93 to 1.05


CK

0.15

1.00

-0.40

1.01

-1.63

1.02

-1.20

1.01

-0.98

1.03

-0.66

1.02

0.31

0.99


CK

-0.19 to 0.49

0.99 to 1.01

-1.43 to 0.62

1.00 to 1.03

-2.54 to -0.71

1.00 to 1.03

-2.89 to 0.50

0.98 to 1.03

-2.80 to 0.85

1.00 to 1.06

-1.48 to 0.17

1.00 to 1.03

-2.11 to 2.74

0.95 to 1.03


CKMB

0.23

0.94

-0.62

1.15

-0.15

1.01

0.42

0.87

-0.11

1.03

-0.10

1.01

0.01

0.98


CKMB

-0.11 to 0.58

0.85 to 1.02

-2.29 to 1.05

0.74 to 1.56

-0.40 to 0.09

0.96 to 1.06

-1.06 to 1.89

0.50 to 1.24

-0.55 to 0.33

0.91 to 1.14

-0.64 to 0.44

0.87 to 1.15

-0.26 to 0.29

0.92 to 1.05


FT3

0.08

0.98

-0.18

1.05

-0.20

1.06

-0.01

1.00

-0.08

1.05

-0.24

1.07

-0.06

1.02


FT3

-0.10 to 0.26

0.93 to 1.03

-0.36 to -0.00

1.00 to 1.11

-0.42 to 0.03

0.99 to 1.12

-0.27 to 0.24

0.93 to 1.08

-0.52 to 0.17

0.96 to 1.14

-0.67 to 0.20

0.95 to 1.18

-0.28 to 0.17

0.96 to 1.08


FT4

-0.22

1.02

-0.69

1.05

-0.76

1.05

-0.05

1.00

-0.56

1.04

0.73

1.04

-0.17

1.01


FT4

-0.63 to 0.19

0.99 to 1.04

-1.88 to 0.51

0.97 to 1.12

-2.40 to 0.89

0.95 to 1.15

-1.60 to 1.49

0.90 to 1.09

-1.45 to 0.34

0.98 to 1.09

-2.01 to 0.54

0.97 to 1.12

-1.07 to 0.74

0.95 to 1.06


GGT

0.47

1.00

-0.23

1.01

0.22

1.00

0.44

0.99

-0.15

1.01

-0.95

1.02

-0.78

1.01


GGT

0.12 to 0.83

0.98 to 1.01

-1.26 to 0.80

0.99 to 1.03

-0.22 to 0.65

0.99 to 1.02

-0.35 to 1.22

0.97 to 1.01

-1.00 to 0.70

1.00 to 1.03

-2.37 to 0.47

1.00 to 1.05

-2.53 to 0.96

0.98 to 1.04


HCGbeta

0.00

1.01

-0.01

1.01

0.00

0.98

0.00

0.97

0.00

1.01

0.00

1.02

0.00

1.01


HCGbeta

-0.01 to -0.00

0.98 to 1.03

-0.01 to 0.00

0.97 to 1.05

-0.01 to 0.00

0.94 to 1.02

0.00 to 0.01

0.92 to 1.02

-0.01 to 0.00

0.97 to 1.04

-0.01 to 0.00

0.98 to 1.05

0.00 to 0.00

0.97 to 1.05


In the second column from the left (headed 11:22), the triplicates of tubes '11' are compared with the triplicates of tube 22. The constant bias (i.e. intercept) and its 95% confidence intervals (CI) as well as the proportional bias (i.e. slope) and its confidence interval are listed. The confidence intervals for the constant bias should include 0.00, and that of proportional bias 1.00, in order to prove the identity of the methods. The columns to the right contain identical data for comparison, 15 versus 10 min centrifugation, 15 versus 7 and 10 versus 7 min. Further to the right, the same comparisons were made for the '22'-tubes. The full list of comparisons is given as table S1 in additional files.

Minder et al. BMC Clinical Pathology 2011 11:6   doi:10.1186/1472-6890-11-6

Open Data