Mark J. Buller

Acceptability of a Wearable Vital Sign Detection System

This study assessed the human factors issues associated with wearing a Vital Sign Detection System (VSDS), a body worn physiological monitoring system. Experienced combat Soldiers (n = 27) participated in a combat training exercise of ∼ 120 hr while wearing the VSDS. They were then given a questionnaire to assess comfort, physical impact on the body, and acceptability of the VSDS as well as questions on fit, impact on performance, and durability of the VSDS. Comfort was impacted the most by the VSDS when in the prone position, possibly affecting sleep, and prone position rifle shooting. Skin irritation or discomfort was reported in 85% of respondents. Sixty-two percent thought the VSDS was not acceptable to wear for ≥ 8 hr. Yet, at the same time, 92% of Soldiers approved of the concept for health monitoring, and 89% said they would wear the VSDS as is if it could help save their life. The VSDS needs to be modified to be more comfortable before it can be fielded for medical monitoring of Soldiers in the field.

Acceptability and Usability of an Ambulatory Health Monitoring System for Use by Military Personnel

OCCUPATIONAL APPLICATIONS A physiological status monitoring system was evaluated for use by soldiers in the field. Two different designs were evaluated, with the design based on previous human factors evaluations proven to be more comfortable and acceptable for use. This study demonstrated that the advanced design of the EQ-02 physiological status monitoring system met dismounted soldier needs. Furthermore, this study validated the use of a usability evaluation in the successful design/advancement of a physiological status monitoring system. TECHNICAL ABSTRACT Background: Previous research has shown that the form factor of a physiological status monitoring system, the Equivital™ EQ-01 (Hidalgo Ltd., Cambridge, UK) had problems associated with comfort and usability of the system for soldiers. Previous data gathered was used to guide improvements in the physiological status monitoring system. Purpose: Assess whether the previous feedback from usability evaluations helped guide improvements in comfort, acceptability, and usability of a physiological status monitoring system for dismounted soldiers. Improvements to the EQ-01 system were incorporated into the next-generation EQ-02 (Hidalgo Ltd., Cambridge, UK) system. Methods: Thirty-nine infantry dismounted soldiers were randomly assigned to wear either an EQ-01 or EQ-02 system while performing standard military field training. They filled out a survey on fit, comfort, irritation to the body, impact on military performance, and acceptability. They then wore the other system and filled out the same survey. Results: The Equivital™ EQ-02 system was superior in terms of fit (51% better in overall fit), ease of donning (10% easier), comfort (45% more comfortable), impact on military performance (45% less impact), impact on the body (17% less impact), and acceptability (32% more acceptable). All these measures are subjective self-report ratings. Conclusions: A human factors engineering approach provided an effective means of guiding improvements and the production of a physiological status monitoring system that dismounted soldiers were more likely to accept and wear.

Guest Editorial - 13th Body Sensor Networks Symposium

Tthe BSN 2016 meeting in the University of California at San Francisco (UCSF) Mission Bay conference center focused on neuroscience applications including stress and behavior monitoring and chronic disease management. Keynote presentations highlighted the use of pattern analysis and smart shoes to manage Parkinson’s disease, and bioengineering advances in detecting electrodermal activity at the wrist associated with epilepsy and psychologically stressful events. The themes of the conference are described. A workshop sponsored and organized by Friedrich Alexander University, Erlangen, previewed this theme of automated sensor-based mobility analysis for chronic disease management.

Subcutaneous Glucose Concentration as a Predictor Variable for Energy Expenditure during Resistance Exercise in Humans

The paper describes concurrent, minute-by-minute dynamics of subcutaneous glucose concentration and energy expenditure in young male subjects performing 40-min resistance exercise in a whole room calorimeter. The observed negative correlation between subcutaneous glucose concentration, as measured by continuous glucose monitoring (CGM) sensor and energy expenditure is exploited to propose and validate a simple linear model, which is used to estimate minute-by-minute energy expenditure from CGM sensor readings. The data were collected from seven young adult male subjects during their 48-hour stay in calorimeter room. Each subject had two 48-hour calorimeter sessions, except one subject who only performed one session. The minute-by-minute CGM data were regressed on energy expenditure (EE) data thus obtaining a linear model connecting these two quantities. This model was subsequently used to estimate EE from CGM readings for the data that were not used in the training dataset. The performance of the linear regression models was analyzed using Bland-Altman plots and it is demonstrated that the CGM sensor can provide a valid predictor variable which can be combined with other physiological parameters to estimate energy expenditure in field conditions.