Transfer of values from CAL to X in the NORIP project and The Nordic Trueness Project.

Exactly the same calculations have been done in both projects: First a factor for each laboratory (X/CAL), then mean and s calculated after removal of factors deviating more than 4s from mean (mean and s from all labs); numbers of labs before and after removal Ntot and Nrest respectively.

Uncertainty of difference calculated as u=(s12/n1 + s22/n2)1/2 and z = (m1-m2)/u

p is significance of difference

Conclusion:

% difference is significant for 4 components on 1% level, all absolute differences <=0.8% exept for bilirubin which is 2.8%.

The material handling in the two projects is a bit different, samples were sent on dry ice in NORIP project but thawed in the Trueness project.

 

NORIP

IMEP

DIFFERENCE

deleted |factor-m| > 4s

deleted |factor-m| > 4s

Component

Median

M

s

Nrest

Ntot

M

s

Nrest

Ntot

%diff

z

p

Na

1.02474

1.02363

0.00787

112

113

1.02452

0.00693

126

128

-0.1 %

-0.92

0.36

K

1.00000

0.99806

0.01110

112

113

0.99893

0.00922

126

128

-0.1 %

-0.65

0.51

Creatinin

1.04869

1.04988

0.03269

111

112

1.04718

0.01621

129

131

0.3 %

0.79

0.43

Urea

1.02084

1.02124

0.02071

103

104

1.02322

0.01571

127

127

-0.2 %

-0.80

0.42

Protein

1.02526

1.02346

0.01422

86

86

1.02197

0.00784

88

89

0.1 %

0.85

0.39

Albumin

1.02014

1.01896

0.01592

114

115

1.02637

0.01212

125

127

-0.7 %

-4.02

0.00006

**

Glucose

0.98810

0.98696

0.01354

100

101

0.98708

0.01365

126

128

0.0 %

-0.07

0.95

Ca

1.02236

1.02066

0.01477

110

111

1.02566

0.00975

119

120

-0.5 %

-3.00

0.0027

**

Mg

1.01297

1.01456

0.02419

87

87

1.01686

0.01758

91

92

-0.2 %

-0.73

0.47

P inorg

1.01264

1.01262

0.01804

107

107

1.01289

0.01113

105

106

0.0 %

-0.13

0.90

Uric acid

1.06398

1.06204

0.01629

109

110

1.06769

0.02223

122

124

-0.5 %

-2.22

0.026

*

Cholesterol

1.06318

1.06294

0.01697

113

113

1.06500

0.01110

122

123

-0.2 %

-1.09

0.27

Trigly

0.98479

0.98244

0.02047

110

111

0.99075

0.01203

107

108

-0.8 %

-3.65

0.00026

**

Bilirubin

1.04418

1.05476

0.05281

113

114

1.08468

0.07068

119

121

-2.8 %

-3.66

0.00025

**

ALP

1.09783

1.09812

0.01854

102

103

Amylase

1.03470

1.03488

0.02579

77

78

AST

1.07576

1.07706

0.03070

99

100

Alt

1.36955

1.37521

0.11038

112

112

CK

1.12051

1.12436

0.02375

105

105

LD

1.11331

1.11108

0.05252

96

96

Fe

0.94591

0.94273

0.01806

96

97

0.94010

0.02674

96

97

0.3 %

0.80

0.42

TIBC

1.01337

1.01252

0.01608

36

37

T4

1.01612

1.01430

0.03701

7

7

GT

0.98413

0.98690

0.02871

99

100

0.98713

0.01256

108

109

0.0 %

-0.08

0.94

TSH

1.22341

1.21307

0.06997

10

10

Ferritin

1.06838

1.05957

0.03515

8

8

P-Amylase

1.07819

1.07903

0.01950

33

33

HDL

1.04359

1.04172

0.02083

106

107

1.04543

0.02157

100

101

-0.4 %

-1.25

0.21