Perceived Acceptability, Design Preferences, and User Requirements for a Proposed Ear-Worn Device for Heart-Rate and Ear-Temperature Monitoring with Localized Neck Cooling: A Pre-Prototype Mixed-Methods Study in People with Multiple Sclerosis

Background/Objectives: Heat sensitivity in multiple sclerosis (MS) can worsen neurological symptoms and impair daily functioning and quality of life. As current cooling strategies are largely reactive, wearable technology may offer a proactive approach, provided it is acceptable to users. This pre-prototype study evaluated the perceived acceptability of a proposed ear-worn device, not yet fabricated, that would measure ear-site temperature and heart rate, alert the user, and direct localized airflow at the neck, and identified the user priorities that should guide its development. No technical feasibility or device-performance testing was performed. Methods: Adults with MS completed an electronic questionnaire on design preferences, functional features, and overall acceptability; a subset took part in semi-structured interviews analyzed thematically. Results: Forty-seven participants completed the survey. Comfort during prolonged use (72.3%) and compatibility with prescription glasses (66.0%) were the design features most often rated important; health reports (93.6%), communication with healthcare providers (91.5%), symptom monitoring (89.4%), emergency contact (85.1%), and automatic cooling activation (83.0%) were each rated important by more than 80% of participants, with overlapping confidence intervals that do not permit these functions to be ranked. Anticipated acceptability of the concept was uncertain: 46.8% (95% confidence interval [CI] 33.3–60.8) expressed some degree of acceptability (34.0% when only ‘acceptable’ or ‘very acceptable’ responses were counted), 36.2% were neutral, and 17.0% found it not acceptable. Six interviews generated four themes: uncertainty, the impact of heat on daily life, independence through self-management, and practical considerations for implementation. Conclusions: These findings reflect anticipated, concept-level acceptability rather than acceptability after use of a physical device. Because the proposed device would measure ear-site temperature and heart rate rather than neurological symptoms, the priority given to symptom monitoring is addressed through physiological early warning combined with user-reported symptoms. The identified priorities are translated into measurable specifications and verification tests for the next prototype; the technical performance of the device, including its cooling capacity, remains to be demonstrated.