Development of a behaviour-based measurement tool with defined intervention level for assessing acute pain in cats.

OBJECTIVES To develop a composite measure pain scale tool to assess acute pain in cats and derive an intervention score. METHODS To develop the prototype composite measure pain scale-feline, words describing painful cats were collected, grouped into behavioural categories and ranked. To assess prototype validity two observers independently assigned composite measure pain scale-feline and numerical rating scale scores to 25 hospitalised cats before and after analgesic treatment. Following interim analysis the prototype was revised (revised composite measure pain scale-feline). To determine intervention score, two observers independently assigned revised composite measure pain scale-feline and numerical rating scale scores to 116 cats. A further observer, a veterinarian, stated whether analgesia was necessary. RESULTS Mean ± sd decrease in revised composite measure pain scale-feline and numerical rating scale scores following analgesia were 2 · 4 ± 2 · 87 and 1 · 9 ± 2 · 34, respectively (95% confidence interval for mean change in revised composite measure pain scale-feline between 1 · 21 and 3 · 6). Changes in revised composite measure pain scale-feline and numerical rating scale were significantly correlated (r = 0 · 8) (P < 0001). Intervention level score of ≥4/16 was derived for revised composite measure pain scale-feline (26 · 7% misclassification) and ≥3/10 for numerical rating scale (14 · 5% misclassification). CLINICAL SIGNIFICANCE A valid instrument with a recommended analgesic intervention level has been developed to assess acute clinical pain in cats that should be readily applicable in practice.