Activated-protein-C (APC) resistance is a serum marker that has been associated with thrombosis (the formation of blood clots often leading to heart attacks) among adults. A study assessed this risk factor among adolescents. To assess the reproducibility of the assay, a split-sample technique was used in which a blood sample was provided by 10 people; each sample was split into two aliquots (sub-samples), and each aliquot was assessed separately. Table 2.19 gives the results.
Table 2.19 APC resistance split-samples data
Compute the average CV over the 10 subjects as an overall measure of variability of the assay. In general, a CV of <10% is considered excellent, ≥10% and <20% is considered good, ≥20% and <30% is considered fair, and ≥30% is considered poor.
How would you characterize the reliability of the APC assay based on these criteria?
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Chapter 2 Solutions
EBK FUNDAMENTALS OF BIOSTATISTICS
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