Psychometric Evaluation of the Patient-Related Nausea and Vomiting Management Barriers Questionnaire

Context: The Nausea and Vomiting Management Barriers Questionnaire (NVMBQ) measures patient-related barriers to antiemetic medication. Objectives: The primary aim of this study was to test the construct validity, internal consistency, and content validity of the NVMBQ. The secondary aim was to develop a shortened version of the NVMBQ. Methods: A quantitative secondary data analysis from a previous cross-sectional study of the NVMBQ (n = 299) was performed. It included analyses of descriptive data, factor structure, internal consistency, and patient comments. Content validity was established with 10 experts (including patients, nurses, physicians, and scientists) using the item-wise content validity index and the scale CVI (S-CVI). Results: The exploratory factor analysis revealed eight underlying dimensions that were mostly congruent with the hypothesized structure when developing the NVMBQ. Internal consistency was high (α = 0.90). More than 70% of the items were estimated as relevant by the experts. However, the S-CVI was moderate (S-CVI = 0.74). A 14-item short version of the NVMBQ was identified. Qualitative analysis suggested the inclusion of additional clinically relevant items (e.g., the inability to take oral antiemetics if nausea was already present). Conclusion: The NVMBQ provides a good basis for assessing patient-related barriers to chemotherapy-induced nausea and vomiting management. We will use the resulting and translated NVMBQ in a larger study to assess the relationships between chemotherapy-induced nausea and vomiting, patient-related barriers, and current antiemetic regimens.