healthy controls were, for Diamat, mean
(±SD) 5.13% ± 0.33%, the reference range
(mean±2SD) 4.5–5.8%, and the total range
4.4–6.1%. For the PolyCAT A method the
mean (±SD) was 3.43% ± 0.47%, the refer-
ence range 2.5–4.4%, and the range
2.6–5.0%.
Because the methods do not produce identical refer-
ence ranges and because they are not highly concor-
dant, the authors decided that the methods are not
clinically equivalent.
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Laboratory Methods
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