Development and psychometric validation of patient-reported outcome measures (PROMs BCC-20) to assess comfort during chemotherapy in breast cancer patients

Adjuvant chemotherapy is an effective treatment for breast cancer. Chemotherapy causes serious unpleasant side effects and discomfort. Assessment of comfort during chemotherapy is essential to prevent life-threatening and improve the quality of nursing care. Currently, there is no instrument for assessing comfort during chemotherapy in breast cancer patients. This study was conducted in a qualitative and a quantitative phase. The objectives in a qualitative phase were to 1) explore the constructs and themes of the comfort during chemotherapy in breast cancer patients. 2) develop a primary item pool for PROMs questionnaires to assess comfort during chemotherapy in breast cancer patients. The objective in a quantitative phase was to develop and validate PROMs to assess comfort during chemotherapy in breast cancer patients. Qualitative data was collected through semi-structured interviews and analyzed using content analysis. Quantitative data was collected through the Likert scale and validated the psychometric properties of the questionnaire. i.e., content validity, construct validity, reliability via internal consistency, as well as concurrent validity. I-CVI and S-CVI were 0.90 and 0.98, respectively. Cronbach’s alpha coefficient was 0.86. Construct validity was established through EFA. CFA was used to test the accuracy of the structure determined by EFA. The factor analysis revealed five factors and 23 items that explain 60.07% of the total variance. CFA via maximum likelihood with bootstrapping indicated a good fit for the five-component model with 20 items (SRMR = 0.045, RMSEA = 0.040, CFI = 0.947, and TLI = 0.935). Concurrent validity was significantly associated with EORTC QLQ C-30. Thus, the PROMs BCC-20 can be an effective instrument to assess comfort during chemotherapy in breast cancer patients.