Reliability and cut-off point related to the analgesic intervention of a multidimensional composite scale to assess postoperative pain in cats

The aim with this study was to evaluate the reliability, and to establish the minimum score relating to the analgesic intervention of a multidimensional scale for use in assessing postoperative pain in cats undergoing ovariohysterectomy. Thirty cats were video recorded at 4 predetermined moments: prior to surgery, before and after rescue analgesia postoperatively, and 24 hours after surgery. Four observers blind to the times of assessment, and a gold standard observer (researcher who developed the scale) evaluated the video segments in random order using the scale, and determined the adequacy or not of analgesia based on clinical experience. The videos were reassessed two months after the first analysis. The agreement between the assessment of different observers, and the assessment made by the same observer on different occasions has been verified by the intra-class correlation coefficient that ranged from good to very good for all scale items, except activity, attitude and miscellaneous behaviors, which showed moderate reliability. The optimal cutoff point (> 7) was selected based on descriptive analysis and Receiver Operating Characteristic curve. The findings support the reliability in terms of reproducibility and stability, and indicate that analgesic therapy should be considered in scores >8.

cats; pain; scales; reliability; cut-off to rescue analgesia

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