Background: The symptom burden associated with multiple myeloma (MM) is often severe. Presently, no instrument comprehensively assesses disease-related and treatment-related symptoms in patients with MM. We sought to validate a module of the M. D. Anderson Symptom Inventory (MDASI) developed specifically for patients with MM (MDASI-MM).
Methods: The MDASI-MM was developed with clinician input, cognitive debriefing, and literature review, and administered to 132 patients undergoing induction chemotherapy or stem cell transplantation. We demonstrated the MDASI-MM's reliability (Cronbach α values); criterion validity (item and subscale correlations between the MDASI-MM and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and the EORTC MM module (QLQ-MY20)), and construct validity (differences between groups by performance status). Ratings from transplant patients were examined to demonstrate the MDASI-MM's sensitivity in detecting the acute worsening of symptoms post-transplantation.
Results: The MDASI-MM demonstrated excellent correlations with subscales of the 2 EORTC instruments, strong ability to distinguish clinically different patient groups, high sensitivity in detecting change in patients' performance status, and high reliability. Cognitive debriefing confirmed that the MDASI-MM encompasses the breadth of symptoms relevant to patients with MM.
Conclusion: The MDASI-MM is a valid, reliable, comprehensive-yet-concise tool that is recommended as a uniform symptom assessment instrument for patients with MM.