Purpose: To validate the Brazilian version of the Brief Pain Inventory (BPI-B) scale and to determine the optimal cutpoints for mild, moderate, and severe pain based on patients' rating of their worst pain.
Methods: One hundred forty-three outpatients with cancer were recruited in Hospital das Clinicas-University of Sao Paulo, Brazil.
Results: Confirmatory factor analysis confirmed two underlying dimensions, pain severity, and pain interference, with Cronbach's α of 0.91 and 0.87, respectively. Convergent validity was shown by the correlation observed between the BPI dimensions with the EORTC-QLQ-C30 pain scale and the McGill Pain Questionnaire. The BPI-B detected significant differences in the two dimensions by disease and performance status, supporting known-group validity. For the worst pain, the optimal cutpoints were 4 and 7 (1-4 = mild pain, 5-7 = moderate, and 8-10 = severe).
Conclusions: Our data show that BPI-B is a brief, useful, and valid tool for assessing pain and its impact on patient's life.