  We develop and evaluate a respiratory rate estimation algorithm that utilizes
data from pressure-sensitive mat (PSM) technology for continuous patient
monitoring in neonatal intensive care units (NICU). An analysis of the random
effect of drift and systematic effect of creep in the PSM data is presented,
showing that these are essentially dependent on the applied load and contact
surface. Uncertainty measurements are pivotal when estimating physiologic
parameters. The standard uncertainty in the PSM data is here represented by the
percent drift. Next, we evaluate the applicability of PSM technology to
estimate RR in neonatal patient simulator trials under five mixed effects
including internally and externally induced motion, mattress type, grunting,
laying position, and different breathing rates. We analyze the limits of
agreement on the mixed effects model to derive the uncertainty in the estimated
RR obtained through two estimation techniques. In comparison with the gold
standard RR values, we achieved a mean bias of 0.56 breaths per minute (bpm)
with an error bounded by a 95% confidence interval of [-2.26, 3.37] bpm. These
results meet the clinical accuracy requirements of RR within +/-5 bpm.
