Use and abuse of imprecision profiles: some pitfalls illustrated by computing and plotting confidence intervals.

Abstract:

:Published estimates of the imprecision characteristics of immunoassays are often based on quantities of data that seem to be inadequate. The increasing use of imprecision profiles has not necessarily improved the situation. We describe and illustrate a method of computing 95% confidence intervals for profiles estimated directly from replicated assay results. The data used were chosen to mimic the sort of data that are typically available in practice, either within laboratories or from external quality-assessment programs. Use of confidence intervals is an effective pictorial way of incorporating information about the quantity and the distribution of the data used for estimation. This is in keeping with an important property of imprecision profile plots: potentially complex information is summarized in a readily comprehensible way. A computer program is available for estimating and plotting profiles and their 95% confidence intervals.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Sadler WA,Smith MH

subject

Has Abstract

pub_date

1990-07-01 00:00:00

pages

1346-50

issue

7

eissn

0009-9147

issn

1530-8561

journal_volume

36

pub_type

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