Measurement Properties of the Brazilian-Portuguese Version of Memorial Symptom Assessment Scale in Hospitalized Patients Undergoing Chemotherapy: A Longitudinal Study.

OBJECTIVE: To evaluate the reliability, validity and responsiveness of the Memorial Symptom Assessment Scale (MSAS) in adult patients undergoing chemotherapy. METHODS: Longitudinal study including 61 patients hospitalised for chemotherapy for gastrointestinal, lung or breast cancer. The MSAS (total score and subscales: psychological symptoms-PSYCH, physical symptoms-PHYS, and global distress-GDI) was administered at three time points: baseline to test convergent validity with Brief Fatigue Inventory-BFI, 24 hours later to test reliability, and 72 hours after the start of chemotherapy to assess responsiveness. RESULTS: The MSAS showed validity with the BFI (PSYCH: r = 0.41, p = 0.001; PHYS: r = 0.44, p < 0.001; GDI: r = 0.52, p < 0.001; total: r = 0.54, p < 0.001). Reliability was substantial (ICC PSYCH = 0.87; PHYS = 0.86; GDI = 0.86; total = 0.82) and measurement error was classified as very good (SEM PSYCH = 0.12; PHYS = 0.30; GDI = 0.23; total = 0.54). The effect size for change over time ranged from small to moderate (d PSYCH = 0.27; PHYS = 0.27; GDI = 0.38; total = 0.58). External responsiveness by ROC curve analysis was absent for PSYCH (0.53), GDI (0.50), PHYS (0.37) and total score (0.62). CONCLUSION: The MSAS demonstrated substantial reliability, adequate validity and limited to moderate responsiveness, supporting its use for the assessment of physical and psychological. However, the MSAS is limited in its ability to detect clinical change over time.