Interlaboratory variability of bilirubin measurements.
During an 8-month study, 14 laboratories used automated analytical systems to measure total bilirubin concentrations in lyophilized bovine specimens containing 38, 169, and 253 micromol/L bilirubin (2.2, 9.9, and 14.8 mg/dL, respectively). The measured mean +/- SD (n, range) were: 39 +/- 7 micromol/L (n = 90, 31-53) [2.3 +/- 0.4 mg/dL (1.8-3.1)]; 176 +/- 29 micromol/L (n = 89, 146-222) [10.3 +/- 1.7 mg/dL (8.5-13.0)]; and 260 +/- 43 micromol/L (n = 103, 208-316) [15.2 +/- 2.5 mg/dL (12.1-18.5)]. In comparison with target values, measurements were consistently lower at 4, higher at 6, and within +/- 4% at 4 laboratories for each of the three concentrations. The measured values for each concentration remained fairly constant during the study at each laboratory. We conclude that bilirubin measurements differed significantly from the established target values at most of the participating laboratories.
Vreman
H J
HJ
Stanford University, Palo Alto, CA, USA.
Verter
J
J
Oh
W
W
Fanaroff
A A
AA
Wright
L L
LL
Lemons
J A
JA
Shankaran
S
S
Tyson
J E
JE
Korones
S B
SB
Bauer
C R
CR
Stoll
B J
BJ
Papile
L A
LA
Donovan
E F
EF
Ehrenkranz
R A
RA
Stevenson
D K
DK
D000818:Animals; D001322:Autoanalysis / Q000706:statistics & numerical data*; D001663:Bilirubin / Q000097:blood*; D002417:Cattle; D006801:Humans; D007753:Laboratories / Q000706:statistics & numerical data*; D011786:Quality Control; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine
D012710:Serum Albumin, Bovine; D001663:Bilirubin