A Novel Approach to the Use of Animals in Studies of Pain: Validation of the Canine Brief Pain Inventory in Canine Bone Cancer

To validate the Canine Brief Pain Inventory (CBPI), which is based on the human Brief Pain Inventory (BPI), in a canine model of spontaneous bone cancer. One hundred owners of dogs with bone cancer self-administered the CBPI on three occasions to test the reliability, validity, and responsiveness of the measure. Factor analysis, internal consistency, convergent validity, and an extreme group validation assessment were completed using the responses from the first administration of the CBPI. Test-retest reliability was evaluated using two administrations of the instrument, 1 week apart. Responsiveness was tested by comparing responses 3 weeks apart. The "severity" and "interference" factors hypothesized based on the BPI were demonstrated in the CBPI in dogs with bone cancer. Internal consistency was high (Cronbach's alpha, 0.95 and 0.93), as was test-retest reliability (kappa, 0.73 and 0.65). Convergent validity was demonstrated with respect to quality of life (r = 0.49 and 0.63). Extreme group validation against normal dogs showed significantly higher factor scores (P < 0.001 for both). The CBPI reliably measures the same pain constructs in the companion canine model of spontaneous bone cancer as the BPI does in people with bone cancer. This innovative approach to preclinical outcomes development, validating a preclinical outcome measure that directly corresponds to an outcome measure routinely used in clinical research, applied to a readily available animal model of spontaneous disease could transform the predictive ability of preclinical pain studies.