X-QST: A Wireless Thermal Quantitative Sensory Testing System Integrated into a Ubiquitous Health Platform—Development and Pilot Evaluation in Healthy Adults

Thermal analyses using Quantitative Sensory Testing (QST) play a crucial role in supporting the diagnosis of diabetic peripheral neuropathy (DPN), as small thermal fibers are the first to be affected in such cases. This study presents the development of X-QST, a system designed to perform thermal QST procedures, integrated into the ubiquitous health platform Screening for Diabetes Complications (SDC-X), developed at the Institute of Biomedical Engineering of the Federal University of Santa Catarina (IEB-UFSC). The system comprises a wireless acquisition module and a data management module and performs warm and cold detection threshold tests, heat pain threshold tests, and evaluation of paradoxical heat sensations. A pilot study involving 15 healthy adults was conducted to evaluate the system, and the results were compared with normative reference values using Z-score transformation, the group-comparison t-test proposed with the reference dataset, and exact tests of the proportion of abnormal classifications. Most participants’ results fell within the normal range, and the proportion of abnormal classifications did not differ from that expected under the normative criterion for the detection thresholds and for paradoxical heat sensations. Heat pain threshold data are reported separately for the two subgroups defined by a change in the verbal instruction during the pilot and are not pooled. These findings demonstrate the technical feasibility of the X-QST subsystem and its integration into the SDC-X platform in a sample of healthy adults. Diagnostic performance for DPN was not assessed in this study; validation in individuals with diabetes mellitus, with and without peripheral neuropathy, is required before any screening use and is the planned next step.