AJP - Endocrinology and Metabolism, Vol 257, Issue 1 E88-E94, Copyright © 1989 by American Physiological Society
Biophysical modeling of sensitivity and positive accuracy of detecting episodic endocrine signals
R. J. Urban, M. L. Johnson and J. D. Veldhuis
Department of Internal Medicine, University of Virginia School of Medicine, Charlottesville 22908.
To investigate the nature of false-negative and false-positive errors in
endocrine signal detection, we used a multiparameter convolution procedure
to create random hormone secretory bursts. We observed that 1) data
containing high signal frequency, amplitude, and/or duration can be
analyzed at less stringent peak-detection thresholds; 2) for any given
secretory burst amplitude, increasing the peak-detection threshold enhances
positive accuracy but decreases sensitivity; 3) increased sampling
frequency improves sensitivity but requires more stringent peak-detection
thresholds; and 4) increasing noise diminishes both sensitivity and
positive accuracy. We conclude that secretory properties, peak-detector
thresholds, investigator-specified sampling intensity, and experimental
variance all significantly influence false-positive and false-negative
errors associated with the enumeration of episodic endocrine pulse signals.
The present observations should offer objective principles to aid in the
rational design and analysis of neuroendocrine studies of pulsatile
physiological phenomena.
