Measuring the Symptom Experience of Patients with Cancer in Indonesia: Cross-cultural Adaptation and Validation of the Memorial Symptom Assessment Scale Indonesian Version.

CONTEXT: Little is known about cancer-related symptoms in terms of prevalence, severity, and distress among patients with cancer in Indonesia due to a lack of a valid and reliable scale.

OBJECTIVE: to translate and validate the Memorial Symptom Assessment Scale (MSAS) among cancer patients in Indonesia.

METHODS: Two procedures consisting of forward-backward translation and validation were conducted. The validation process including pre-testing involved 34 cancer patients, and the psychometric testing of the Indonesian Version of MSAS (MSAS-I) involved 207 cancer patients. Internal consistency, test-retest reliability, construct, and concurrent validity of the MSAS-I were established.

RESULTS: Cronbach's alpha coefficients for the total scale and subscales of the MSAS-I ranged from 0.75 to 0.87. The interclass correlations for test-retest reliability ranged from 0.80 to 0.89. A two-factor structure in the MSAS-I was produced by exploratory factor analysis, and the two factors accounted for 28.34% of the cumulative variance. In addition, the concurrent validity was demonstrated by the significant associations between the subscales of the MSAS-I and their corresponding subscales in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C 30, with r = -0.25 to -0.65 (all p < 0.001).

CONCLUSION: The MSAS-I presents a valid and reliable scale for assessing symptom frequency, severity, and distress among patients with cancer in Indonesia.

IMPLICATION FOR NURSING: The MSAS-I can assess physical and psychological symptoms during cancer treatment. In addition, the MSAS-I may facilitate in measuring the effectiveness of symptom management strategies.