Validating the M. D. Anderson Symptom Inventory (MDASI) for use in patients with ovarian cancer

Objective: The M. D. Anderson Symptom Inventory (MDASI) captures the severity of common cancer symptoms from the patient's perspective. We describe the validity and sensitivity of a module of the MDASI to be used with patients having ovarian cancer (MDASI-OC).

Methods: Ovarian cancer-specific module items were developed from 14 qualitative patient interviews. 128 patients with invasive epithelial ovarian, peritoneal, or fallopian-tube cancer treated at The University of Texas MD Anderson Cancer Center were recruited. Patients completed the MDASI-OC, socio-demographic questionnaires, the Functional Assessment of Cancer Therapy-Ovary (FACT-O), and a global quality-of-life (QOL) item. Reliability was assessed using Cronbach α, and sensitivity using a known group was assessed. Construct validity was tested using exploratory factor analysis.

Results: The sample was primarily white (85.2%), had a mean age of 57.5 years (±12.7 years), and had previously been treated with chemotherapy (75.0%) and/or surgery (93.8%). Approximately 30% of patients reported disturbed sleep, fatigue, or numbness/tingling of at least moderate severity (≥5 on a 0-10 scale). On the ovarian-cancer-specific symptoms, approximately 20% reported back pain, feeling bloated, or constipation of at least moderate severity. Factor analysis revealed six underlying constructs (pain/sleep; cognitive; disease-related and numbness; treatment-related; affective; gastrointestinal-specific). MDASI-OC symptom and interference items had Cronbach α values of 0.90 and 0.89, respectively. The MDASI-OC was sensitive to symptom severity by performance status (p=0.009), QOL (p=0.002), and FACT-O scores (p<0.001).

Conclusions: The 27-item MDASI-OC meets common criteria for validation and reliability and is sensitive to expected changes in symptoms related to differences in disease and treatment status.