Validity and reliability of multiparameter physiological measurements recorded by the Equivital LifeMonitor during activities of various intensities.

The Equivital LifeMonitor EQ02 is a multiparameter body-worn system capable of logging and transmitting physiological data describing a wearer's cardiorespiratory and thermal status. A number of vital signs can be acquired by the system, including electrocardiography, respiratory inductance plethysmography, posture/activity, multipoint skin temperature, and core temperature. The validity and reliability of the multiparameter physiological data recorded by the EQ02 were assessed. Participants performed resting, low-, and moderate intensity activities and wore the EQ02 and other calibrated laboratory physiological monitoring devices simultaneously. Heart rate, respiratory rate, multipoint skin temperature, and core temperature recorded by the EQ02 were compared with measurements recorded by standard devices. Results show that the validity error scores for HR and RR for all three activities were not significantly different from zero, and the CV, 95% LOA, and r were all clinically accepted. The validity error score for MT(SK) (0.59°C) falls outside the limits of 0.5°C, but the differences were parallel, r remained high (0.96), and 95% LOA remained narrow (±0.88°C). The validity error score for T(C) (-0.1°C) was similar in direction and magnitude to other studies, and r (0.98) and 95% LOA (±0.22°C) showed acceptable agreement between devices. The reliability error scores for HR, RR, MT(SK), and T(C) between trials were significantly different from zero. The 95% LOA, CV, and ICC for the EQ02 were similar to standard devices and were all clinically accepted. These findings demonstrate the validity and reliability of the EQ02 for ambulatory monitoring of multiple physiological parameters and suggest that the system could be used to provide a complete human physiological monitoring platform for the study of occupational health, environmental hygiene, and other application fields requiring ambulatory monitoring of multiparameter physiological status.