Table 1 Results on Passing-and-Bablok-fit analyses for phenylalanine and tyrosine concentrations in LH plasma, EDTA plasma, and capillary DBS

Median (range)

intercept

slope

R

intercept

slope

R

intercept

slope

R

LH plasma

326 (20–1574)

EDTA plasma

321 (23–1707)

−2.1

1.10*

0.991

Capillary DBS

325.5 (26.8–1580)

2.8

1.00

0.993

9.7

0.92*

0.978

Venous DBS

309 (25.9–1490)

7.5

0.98

0.990

6.1

0.93*

0.981

0.7

1.01

0.984

LH DBS

297 (23.5–1610)

6.5

0.96*

0.996

4.7

0.88*

0.985

−0.7

0.98

0.991

EDTA DBS

311 (26.4–1550)

6.3

0.96*

0.995

5.9

0.89*

0.984

−0.6

1.00

0.992

Median (range)

intercept

slope

R

intercept

slope

R

intercept

slope

R

LH plasma

61 (25–804)

EDTA plasma

72 (29–912)

0.0

1.12*

0.982

Capillary DBS

68.25 (24.2–881)

6.4*

1.02

0.930

6.8*

0.93*

0.903

Venous DBS

67 (26.8–871)

3.3

1.04

0.934

4.6

0.92*

0.934

−0.9

0.99

0.934

LH DBS

64.1 (23.1–845)

1.8

1.05

0.951

−0.1

0.96

0.937

−4.1

1.01

0.964

EDTA DBS

70.9 (24.1–793)

4.5

0.98

0.959

4.7

0.91

0.934

−1.3

0.97

0.959