AJP - Endocrinology and Metabolism, Vol 248, Issue 4 475-E481, Copyright © 1985 by American Physiological Society
Minimizing false-positive errors in hormonal pulse detection
J. D. Veldhuis, A. D. Rogol and M. L. Johnson
To explore the problem of type I (false-positive) statistical errors
associated with enumerating endocrine pulses, we used the analysis of
immunoactive luteinizing hormone (LH) pulses as a paradigm. In this system,
the distribution of measurement error was found to approximate a Gaussian
pattern. Moreover, the choice of a fixed threshold criterion to identify a
hormone pulse (as generally undertaken to date) was shown to yield
significantly different false-positive error rates under different
experimental conditions. Therefore, we developed a technique to minimize
the detection of false-positive signals and to maintain an essentially
uniform error rate among different experimental groups. This simple
technique requires that the pulse-detection threshold be adjusted in
relation to the degree of intra-assay measurement error present. Our method
should facilitate the valid comparison of endocrine pulse frequencies in
normal physiological states vs. those associated with hormonal deficiency
when measurement error is typically greater. In addition, this approach
will aid in a more meaningful assessment of pulse concordance between two
or more different hormonal species (i.e., in different assays) and will
assist in comparisons of pulse properties quantitated in different
laboratories. In summary, rates of false-positive pulse detection using
conventional fixed-threshold criteria are materially influenced by even
small differences in within-assay variance. We present a technique to
minimize this type I statistical error and to maintain an essentially
uniform error rate among different experimental groups.
