Measuring the symptom burden associated with the treatment of chronic myeloid leukemia

We developed a module of the MD Anderson Symptom Inventory (MDASI) for patients with chronic myeloid leukemia (CML). To develop the MDASI-CML, we identified CML-specific symptoms from qualitative interviews with 35 patients. A list of candidate symptoms was reduced by a panel of patients, caregivers, and clinicians to the 13 core MDASI symptom items and 6 CML-specific items; these items were subsequently administered to 30 patients. Cognitive debriefing confirmed that the items were clear, relevant, and easy to use. One additional CML-specific symptom item was added, for a total of 7. The refined MDASI-CML was administered to 152 patients once every 2 weeks for 1 year. The content, concurrent, known-group, and construct validity of the MDASI-CML were evaluated. The internal consistency and test-retest reliabilities of the module were adequate. Longitudinal analysis showed relatively stable symptom severity scores over time. The most severe symptoms were fatigue, drowsiness, disturbed sleep, muscle soreness and cramping, and trouble remembering things. Approximately one-third of the patients who completed the MDASI-CML reported persistent moderate-to-severe symptoms. The MDASI-CML is a valid and reliable symptom assessment instrument that can be used in clinical studies of symptom status in patients with CML.