38
| 4 | 2011
Klinisk Biokemi i Norden
(
Fortsat fra side 37)
Konklusjon
Vi foreslår å vurdere prøvematerialets holdbarhet ut
fra enkle krav til bias og totalfeil: Holdbarhet krever
at 90%-konfidensintervallet rundt gjennomsnittet i sin
helhet ligger innenfor gjennomsnittlig utgangsverdi
±tillatt bias
og
at alle enkeltverdier ligger innenfor
utgangsverdi ±tillatt totalfeil. På den måten hindrer
vi både at oppbevaring gir for store systematiske end-
ringer og for store endringer i enkeltprøver.
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Blodvaxskivling (Hygrocybe coccinea). Foto: Henrik Alfthan