Concept domain validation and item generation for the Treatment-Induced Neuropathy Assessment Scale (TNAS)

Purpose: Treatment-induced peripheral neuropathy (TIPN) is a difficult problem experienced by patients with cancer that can interfere with their ability to receive optimal therapy. The Treatment-Induced Peripheral Neuropathy Scale (TNAS) is a patient-reported outcome (PRO) measure developed to assess TIPN symptom burden. However, PRO validation is an ongoing process. The aim of this qualitative study was to define the conceptual model, establish content domain validity, and refine items for the TNAS based on patient input. Methods: Patients who received bortezomib, oxaliplatin, or platinum–taxane combination therapy reported their experience of TIPN in single qualitative audiotaped interviews. Themes of the TIPN experience were identified by descriptive analysis of the transcribed interviews. Results: Three groups of 10 patients each who had received bortezomib, oxaliplatin, or platinum–taxane combination therapy, for a total of 30 patients, reported their experiences. Two themes reported by patients were TIPN sensations and functional interference. Five sensations (numbness, tingling, pain, heat or burning, and coldness) and five functional impacts (using hands, walking, maintaining balance or falling, wearing shoes, and sleeping) were reported by at least 20% of patients and were selected for inclusion in the TNAS v3.0 for additional psychometric testing. Conclusions: The assessment of TIPN must be convenient, reliable, and practical for patients, who are the most reliable source of information about symptoms. The TNAS, developed with direct patient input, provides an easily administered and conceptually valid method of patient report of TIPN burden for use in research and practice.