A Comprehensive Review of the Clinical Utility and Reliability of a Quantitative Electrical Stimulation Device for Objective Pain Assessment

Objective: Objective pain measurement remains challenging due to pain's subjective nature. This review evaluates the clinical utility, measurement protocols, reliability, and limitations of a quantitative electrical stimulation device used for objective pain perception threshold assessment. Methods: A systematic literature search was conducted in November 2025 using Web of Science and PubMed databases without date restrictions. Studies involving human subjects that employed the device for quantitative pain perception threshold measurement were included. Data on study design, patient populations, measurement protocols, clinical applications, reliability, and validity were extracted and synthesized. Results: Eleven studies met inclusion criteria, encompassing healthy volunteers and patients with neuropathic pain, chemotherapy-induced peripheral neuropathy, chronic pain, and genetic pain sensitivity disorders. The device quantified current perception threshold (CPT) and pain equivalent current (PEC) via controlled electrical stimulation, with electrode placement typically on the forearm, upper arm, fingertips, or ulnar flexion. Measurements demonstrated reproducibility and positive correlations with subjective pain scales such as the Visual Analog Scale (VAS). Variability in protocols, sensitivity to patient movement, and limited assessment of slow C-fiber mediated pain were commonly reported challenges. Conclusion: The electrical pain assessment device is a promising objective tool for pain and sensory function assessment that complements subjective measures. Future research should focus on large-scale validation, standardization of protocols, and integration with other physiological markers to enhance clinical applicability and precision in pain management.