Development and validation of the Chiari-like malformation and syringomyelia evaluation: the CHASE questionnaire

BACKGROUND: Chiari-like malformation (CM) and syringomyelia (SM) in dogs are associated with signs of neuropathic pain and itch, which are difficult to quantify reliably. HYPOTHESIS/OBJECTIVES: Develop and validate the Chiari-like malformation and syringomyelia evaluation (CHASE) questionnaire to quantify owners' assessments of clinical signs of CM/SM in their dogs. ANIMALS: Twenty client-owned healthy dogs and 30 CM/SM affected dogs. METHODS: The CHASE questionnaire was developed using an iterative sampling design, reliability and normal scores were established in healthy dogs. A double-blinded, randomized, crossover study design was conducted using pregabalin and placebo, with CHASE as the primary outcome. Physical and neurologic examinations, activity monitors, quantitative sensory testing (QST), and quality of life assessments (QOL) were performed alongside the CHASE questionnaire at each time point. RESULTS: Baseline CHASE scores were significantly higher in CM/SM dogs compared with healthy dogs (15.3 ± 4.8 vs. 1.4 ± 1.8; P < .01), with score ranges of 6-24 and 0-6, respectively. The CHASE scores in CM/SM dogs were moderately repeatable from screening (15.1 ± 4.4) to baseline (15.1 ± 4.7) and decreased significantly with pregabalin compared with baseline and placebo (P < 0.001 and P < 0.03). The questionnaire had strong internal consistency (α = 0.89) and differentiated pregabalin from placebo with 63% sensitivity and 76% specificity (area under the curve = 0.67). No significant differences in QOL, QST, or activity levels were identified. CONCLUSIONS AND CLINICAL IMPORTANCE: We validated the use of the CHASE questionnaire to quantify clinical signs associated with CM/SM and distinguish treatment outcomes when other assessments failed.