Development and initial validation of the thyroid cancer module of the M. D. Anderson symptom inventory

Objective: The M. D. Anderson Symptom Inventory (MDASI) and its modules measure common symptoms related to cancer and its treatment. We report the development and initial validation of the MDASI-Thyroid Cancer module (MDASI-THY). Methods: A list of thyroid-cancer-specific symptoms was generated through focus groups and interviews with thyroid cancer patients, clinicians and researchers. These MDASI-THY items were added to the original MDASI and administered to 60 patients with thyroid cancer. Symptom prevalence and severity were evaluated, along with the reliability and content, construct and known-group validity of the MDASI-THY. Results: Cognitive debriefing performed on a subset of patients indicated that the MDASI-THY items were clear, concise, relevant and easy to understand. Fatigue, drowsiness, sleep disturbance, distress and difficulty remembering were the 5 most prevalent and severe symptoms. Twenty-eight percent of patients had moderate to severe fatigue (≥5 on a 0-10 scale). Average severity was 1.28 and 1.29 for the symptom and interference subscales, respectively. MDASI-THY symptoms were severer for patients with poorer performance status. Cronbach α-values were 0.76, 0.85 and 0.92 for the thyroid-specific symptom items, core symptom subscale and interference subscale, respectively. Conclusions: This study demonstrates preliminary evidence for the validity and reliability of the MDASI-THY.