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Updated: Aug 21, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
[Simple dynamic model of the human blood pressure regulatory system as based on the orthostatic load sequence]
Abstract:
The two statistical parameter estimation methods, the recursive least squares and the recursive generalized least squares, are dealt with briefly. An additional noncorrelated disturbance is necessary for unbiased parameter estimation in the closed-loop system. The disturbance is realized by an orthostatic load sequence shaped according to the experimental programme. Men and women were subjected to head-up tilt between 10 degrees and 55 degrees. The disturbance, mean blood pressure and heart rate were measured. These discrete data were used for parameter estimation of transfer functions.
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