FIELD-BASED USABILITY STUDY OF PHYSICAL ACTIVITY MONITORING AND SHARING SYSTEM FOR MANUAL WHEELCHAIR USERS WITH SPINAL CORD INJURY

摘要

Manual wheelchair users (MWUs) with spinal cord injury (SCI) have significantly lower levels of physical activity (PA) due to physical limitations, mobility limitations, environmental barriers, and social barriers. Physical inactivity has been shown to lead to obesity and other secondary complications. The use of personal health monitoring technology to increase PA level has become popular among the ambulatory population; however, none of these technologies pertain to the SCI population. In order to fill this gap, the investigators at the Human Engineering Research Laboratories developed a Physical Activity Monitoring and Sharing System (PAMS) that could track PA parameters among MWUs. PAMS consists of a tri-axial accelerometer worn on the arm, a gyroscopic-based wheel rotation monitor (GWRM) mounted on the wheel, and a smartphone application that communicates with the two sensors. The objective of this thesis is to evaluate the feasibility of PAMS in the home environment. The thesis is broken into two parts. The first part describes the preparation work for the field study, and the second part describes the field-based usability testing. Preparation work included the development of PA parameter estimation algorithms and the PAMS app. The estimated PA parameters were distance, energy expenditure (EE), time being active, push count, and push efficiency. The absolute errors for the estimation were 1.7%1.3% for distance, 15.4%9.4% for EE, 37.5%22.1% for time being active, and 11.7%10.0% for push count. The push efficiency was calculated by dividing the distance by push count. The PAMS app presented the PA parameters to users and incorporated several features for promoting PA such as goal-setting, summary, and social interaction. The field-based usability study evaluated PAMS in the home setting for 7 days to identify problems encountered by users and then assessed user experience and satisfaction. Ten MWUs with SCI were recruited, and PAMS scored an 85.56 out of 100 points on the System Usability Scale. The study concluded that MWUs with SCI could use PAMS to track their PA on a daily basis and that they find it useful. PAMS also has the potential to promote an active lifestyle among this population.