Validation of the Edmonton Symptom Assessment System: Ascites Modification.

ABSTRACT

CONTEXT Few patient-reported outcomes are available to measure the symptoms associated with malignant-related ascites in patient care and clinical research. Although the Edmonton Symptom Assessment System Ascites Modification (ESASAM) is a brief tool to measure symptoms associated with malignant-related ascites, it remains to be fully validated. OBJECTIVES: The objective of the study was to validate the ESASAM in Japanese cancer patients. METHODS: We assessed the internal consistency, test-retest reliability, concurrent validity, and construct validity in 292 Japanese adult patients with cancer. They completed Japanese versions of the ESASAM, M.D. Anderson Symptom Inventory, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, and abdominal pain/ascites subscales of the EORTC Core Quality of Life Questionnaire, 26-item pancreatic cancer module. RESULTS: Cronbach's alpha coefficient of the ESASAM was 0.89. The intraclass correlation coefficient on test-retest examination of its total score was 0.93 (P < 0.001). Pearson correlation coefficients of the total score of the ESASAM with the total score of the M.D. Anderson Symptom Inventory and abdominal pain/ascites subscales of the EORTC Core Quality of Life Questionnaire, 26-item pancreatic cancer module ranged from 0.44 to 0.81 (P < 0.001) and those with global health status/quality of life and functional subscales of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 ranged from -0.40 to -0.61 (P < 0.001). The total scores of the ESASAM were significantly higher in 20 patients with symptomatic ascites (34 [SD, 26]) than 267 patients without symptomatic ascites (23 [SD, 19]) (P = 0.018). CONCLUSION: The ESASAM is a reliable and valid tool for measuring symptoms associated with malignant-related ascites and can be used in daily patient care and future epidemiological studies and clinical trials.