Date of Award
8-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Bioengineering
Committee Chair/Advisor
Dr. John DesJardins
Committee Member
Dr. David Neyens
Committee Member
Dr. Joseph Singapogu
Abstract
Severe extremity hemorrhage remains a leading cause of preventable death following traumatic injury, and rapid tourniquet application is critical for improving survival outcomes. Although commercially available tourniquets are highly effective when properly applied, successful use often depends on training, physical capability, and procedural familiarity. These requirements may present challenges for laypersons expected to respond during severe bleeding emergencies. The objective of this study was to evaluate the usability of the EZ Tourniquet (EZTQ), an automated over-the-counter hemorrhage-control device, when operated by untrained civilian users during a simulated emergency response scenario.
Twenty-five participants representing five adult age groups completed an individual simulated-use evaluation involving application of the EZTQ to a bleeding lower-extremity trauma manikin. No formal device training was provided prior to testing. Performance measures included procedural success, completion time, instruction usage, and observed use-related errors. Participants also completed post-test usability and satisfaction surveys and participated in semi-structured interviews to assess subjective perceptions of device operation.
Overall, 23 of 25 participants successfully completed the required application procedure, corresponding to a procedural success rate of 92%. The mean completion time (± 1 standard deviation) among successful applications was 93.6 ± 25.6 seconds. Participants reported favorable usability perceptions across multiple measures, including ease of use (4.40 ± 0.71), learnability (4.28 ± 0.54), perceived safety (4.52 ± 0.71), comfort (4.32 ± 0.75), and perceived effectiveness (4.44 ± 0.77) on five-point Likert scales. Qualitative findings indicated that participants perceived the automated tightening mechanism and integrated audio guidance system as beneficial features that simplified device operation and reduced uncertainty during application. Although some use errors and procedural deviations were observed, most participants successfully recovered from these events and completed the application procedure.
These findings suggest that automation and human-centered design features are important considerations in the development of accessible and usable hemorrhage-control technologies for layperson users. The results support continued development of public-access hemorrhage-control devices that reduce physical and cognitive demands while facilitating successful intervention during bleeding emergencies.
Recommended Citation
Orozco, Enoch S., "Usability Evaluation of an Over-the-Counter Tourniquet Device for Layperson Emergency Use" (2026). All Theses. 4831.
https://open.clemson.edu/all_theses/4831