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PubMed · 328016

Interlaboratory variability of valproic acid determinations.

D Schmidt·B Ferrandes·D Grandjean·R Gugler·C Jakobs·S Johannessen·U Klotz·W Kochen·H J Kupferberg·J W Meijer·A Richens·H Schäfer·H U Schulz·A Windorfer
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Abstract

19 pooled plasma specimens were sent as unknowns to 13 participating research laboratories. The interlaboratory variability between the results was very high. Only 4 out of 13 laboratories had 6--12% of their results within the 95% confidence limit for each sample. The precision of repeated determinations was fairly good. 6 out of 10 participating laboratories had a coefficient of variation of less then 5%. The reproducibility and the agreement between the different procedures for quantitative analysis of dipropylacetate is similar to that reported for other major antiepileptic drugs.

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D Schmidt, B Ferrandes, D Grandjean, R Gugler, C Jakobs, S Johannessen, U Klotz, W Kochen, H J Kupferberg, J W Meijer, A Richens, H Schäfer, H U Schulz, A Windorfer. 1977. Interlaboratory variability of valproic acid determinations.. https://pubmed.ncbi.nlm.nih.gov/328016/

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