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PubMed · 2791282

Multi-factor designs. II. A design for identifying instruments with sample-to-sample carryover and drift.

B Schlain·J S Krouwer
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Abstract

We describe a nearly orthogonal two-level design that involves use of a weighted analysis to estimate drift and very low amounts of sample-to-sample carryover simultaneously. Identifying systematic errors from these sources is especially important for assays of analytes presenting a large range and with a medical decision point close to zero. The design is illustrated with data for thyrotropin, where, in one run with 32 samples, 0.08% carryover was detected in the presence of concentration-dependent negative drift.

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B Schlain, J S Krouwer. 1989. Multi-factor designs. II. A design for identifying instruments with sample-to-sample carryover and drift.. https://pubmed.ncbi.nlm.nih.gov/2791282/

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