Abstract
PURPOSE: To develop a patient self-completed questionnaire from the items of the Brief Core Set Questionnaire for Breast Cancer (BCSQ-BC) and to investigate the prevalence of specific dysfunctions throughout the course of cancer and treatments. METHODS: From January 2010 to February 2011, 96 breast cancer patients were evaluated with BCSQ-BC developed for clinical application of International Classification of Functioning, Disability and Health (ICF). Quality of life and upper limb dysfunction using disabilities of arm, shoulder and hand (DASH) were assessed. Content validity was evaluated using correlations between BCSQ-BC and European Organization for Research and Treatment of Cancer (EORTC) QLQ and DASH scores. Construct validity was computed using exploratory factor analysis. Kappa statistics were computed for agreement between test-retest ICF data. The level of significance and odds ratios were reported for individuals with early post-acute and long-term context and with total mastectomy and breast conservative surgery. RESULTS: There was consistently good test-retest agreement in patient-completed questionnaires (kappa value, 0.76). Body function, activity and participation subscales are significantly related with EORTC QLQ and DASH. Problems with activity and participation were strongly associated with physical functional domains of EORTC QLQ (r=-0.708, p<0.001) and DASH (r=0.761, p<0.001). The prevalence of dysfunctions varied with type of surgery and time after cancer. Immobility of joint (15% vs. 7%) and lymphatic dysfunction (17% vs. 3%) were indexed more frequently in extensive surgery cases than in conservative surgery. Muscle power (16% vs. 8%), exercise tolerance functions (12% vs. 4%) and looking after one's health (10% vs. 2%) were impaired within 1 year after surgery, while sleep dysfunction (8% vs. 14%) was a major problem over 1 year after surgery. CONCLUSION: The BCSQ-BC identifies the problems comprehensively in functioning of patients with breast cancer. We revealed the interaction with the ICF framework adopting a multifactor understanding of function and disability.