Validation of the Donkey Pain Scale (DOPS) for Assessing Postoperative Pain in Donkeys

Abstract

This study aimed to validate a scale for assessing acute pain in donkeys. Forty-four adult donkeys underwent castration after sedation with intravenous (IV) xylazine, induction with guaifenesin and thiopental IV, local anesthetic block, and maintenance with isoflurane. The scale was constructed from a pilot study with four animals combined with algetic behaviors described for equines. After content validation, the scale was evaluated in 40 other donkeys by three blinded and one reference evaluator, by means of edited videos referring to the preoperative and postoperative periods: before anesthesia, 3–4 h after recovery from anesthesia, 5–6 h after recovery from anesthesia (2 h after analgesia with flunixin—1.1 mg/kg, dipyrone—10 mg/kg, and morphine—0.2 mg/kg) IV, and 24 h after recovery. Content validity, sensitivity, specificity, and responsiveness of behaviors were investigated to refine the scale. Intra- and inter-evaluator reliabilities were investigated by the weighted kappa coefficient, criterion validity by comparing the scale with the visual analog scale (VAS), internal consistency by Cronbach's α coefficient, item-total correlation by the Spearman coefficient, and intervention point for rescue analgesic by the receiver operating characteristics curve and Youden index. The scale showed very good intra-evaluator reliability (0.88–0.96), good to moderate (0.56–0.66) inter-evaluator reliability, responsiveness for all items, good criterion validity vs. VAS (0.75), acceptable internal consistency (0.64), adequate item-total correlation, except for head position and direction, and according to the principal component analysis, good association among items. The accuracy of the point for rescue analgesic was excellent (area under the curve = 0.91). The rescue analgesic score was ≥ 4 of 11 points. The scale can diagnose and quantify acute pain in donkeys submitted to castration, as the instrument is reliable and valid, with a defined intervention analgesic score.

Validation of the rabbit pain behaviour scale (RPBS) to assess acute postoperative pain in rabbits (Oryctolagus cuniculus)

“…There are different ways to investigate dimensionality and multiple association between variables according to exploratory and/or confirmatory factor analysis. Principal component analysis, an exploratory analysis, was used herein to maintain consistency with previously validated scales in other species [ 15 , 22 – 25 ]. According to PCA all items pertained to the first dimension, except attention to the affected area, which pertained to the second dimension.…”

“…In other species, behavioural scales designed to assess pain stand out for providing evidence of validity, reliability, and sensitivity [ 21 ] and because they have defined cut-off points, such as that developed for cats [ 15 ], cattle [ 22 ], pigs [ 23 ], sheep [ 24 ], and donkeys [ 25 ].…”

“…Based on the methodology used to validate pain scales in the aforementioned species [ 15 , 22 – 25 ], the current study aimed to validate a scale to assess acute pain resulting from different types of surgeries in rabbits.…”

Multilingual validation of the short form of the Unesp-Botucatu Feline Pain Scale (UFEPS-SF)

“…As expected for an instrument that measures pain, all items’ eigenvectors were pointed to the moments of pain (after surgery and 24 h) and in the opposite direction to moments cats were supposedly pain-free (before surgery) or experiencing mild pain (after rescue analgesia). According to the Kaiser criterion, one component was selected, hence UFEPS-SF is unidimensional ( Streiner, Norman & Cairney, 2015 ) as reported for other pain scales in cattle ( de Oliveira et al, 2014 ), pigs ( Luna et al, 2020 ), sheep ( Silva et al, 2020 ), horses ( Taffarel et al, 2015 ; Barreto da Rocha et al, 2021 ) and donkeys ( de Oliveira et al, 2021 ). The only statistically defined multidimensional animal pain scale in cats is UFEPS ( Brondani et al, 2013b ); however, this classification is based on multivariate analysis and not on biological terms.…”

“…UFEPS was chosen as one of the ‘gold standard’ instruments since it has undergone a robust validity protocol ( Merola & Mills, 2016 ). However, as UFEPS-SF was derived from UFEPS, the CPMS-Feline was also used for comparison ( Reid et al, 2017 ), and so were the unidimensional scales, as previously reported in cats and other species ( Barreto da Rocha et al, 2021 ; Brondani et al, 2013b ; Luna et al, 2020 ; de Oliveira et al, 2014 ; Taffarel et al, 2015 ; Silva et al, 2020 ; de Oliveira et al, 2021 ). The correlations equal to or above 0.9 in all comparisons confirmed concurrent criterion validity.…”