Minimal clinically-important differences for the ‘Liverpool Osteoarthritis in Dogs’ (LOAD) and the ‘Canine Orthopedic Index’ (COI) client-reported outcomes measures

Abstract

Client-reported outcomes measures (CROMs) have been previously validated for the evaluation of canine osteoarthritis. A published systematic review indicated that the ‘Liverpool Osteoarthritis in Dogs’ (LOAD) and the ‘Canine Orthopedic Index’ (COI) can be recommended for use in dogs with osteoarthritis; these CROMs have also been used in the context of measuring surgical outcomes of dogs with orthopaedic conditions. However, the minimal clinically-important differences (MCIDs) for these CROMs have not been investigated. Such estimates would be useful for investigators and regulators so that these CROMs can be used in clinical trials. Data from the RCVS Knowledge Canine Cruciate Registry were extracted, and baseline and 6 week follow-up data on dogs that had received surgery for cranial cruciate ligament rupture were used to make estimates of MCIDs using distribution-based and anchor-based methods. Data from 125 dogs were categorised based on the anchor question and LOAD and COI scores analysed accordingly. The four anchor-based methods provided a range of MCIDs for each CROM (1 to 8.8 for LOAD and 3.5 to 17.6 for COI). In the two different distribution-based methods, the MCIDs for LOAD ranged from 1.5 (effect size) to 2.4 (standard error of measurement) and the effect size method yielded a result of 2.2 for COI. The results showed that the value of the MCIDs depended on the method that was applied. Receiver operator characteristic curves provided areas under the curve (AUCs) greater than 0.7, which indicated that the cut-off point was acceptable; LOAD had the greater AUC at 0.867. In summary, the authors currently recommend a MCID of ‘4’ for LOAD and ‘14’ for COI although further work in other clinical contexts (such as osteoarthritis associated with chronic pain) is required to add confidence to these estimates. For the first time, we have provided estimates for MCIDs for these two CROMs which will facilitate sample size estimates in future clinical studies that use these CROMs as outcomes measures.

A Preliminary Report on the Combined Effect of Intra-Articular Platelet-Rich Plasma Injections and Photobiomodulation in Canine Osteoarthritis

“…With the CBPI, a reduction of ≥1 in PSS and ≥2 in PIS was considered a clinically-important change [41]. The same level has been determined for the LOAD and COI, suggested as a reduction of ≥4 and ≥14, respectively [42]. Unreported data from our group indicate that clinically important changes consist of improvements of ≥1 for deviation and ≥10 for SI in dogs with OA.…”

Minimal Clinically Important Differences for a Weight Distribution Platform in Dogs with Osteoarthritis

“…This evaluation was performed with clinical data available from a clinical setting caring for working police dogs, submitted to different treatments. As for referenced studies looking at determining MCIDs for other clinical outcome instruments [ 27 , 28 ], although we selected a +15 d follow-up moment, this specific follow-up time-point should not be considered a recommendation for post-treatment evaluation in dogs with OA. Rather, it was a time-point chosen based on the previous experience of the clinicians, previous conducted research, and expectation that it would be enough time to obtain a response to treatment and therefore produce different answers to the anchor question, allowing us to estimate the MCID.…”

“…Some of the information presented in the present study was collected during a different project but has not been reported before [ 22 , 23 , 24 , 25 , 26 ]. In this study, we followed a similar methodology outlined in published papers, looking at determining minimal clinically important differences for two client-reported outcomes measures (the Liverpool Osteoarthritis in Dogs—LOAD—and the Canine Orthopedic Index—COI), in dogs with osteoarthritis and following surgery for cranial cruciate ligament rupture [ 27 , 28 ]. For included animals, an anchor question was collected.…”

“…We also calculated the area under the ROC curve (AUC). Based on available reports, AUC values between 0.7 and 0.8 were considered to have acceptable reliability and 0.8 and 0.9 were considered to have excellent reliability [ 28 ].…”

Proper use of client‐reported outcome measures

“…Personally, I feel such ‘drift’ from the original validated tool to be unhelpful. Such fundamental differences are going to cause confusion in the literature and also have consequences in light of other CROMs metrics, such as ‘minimal clinically‐important differences’ 10,11 . Given that regulatory authorities such as the European Medicines Agency and the US Food and Drug Administration are now using validated CROMs in pivotal field studies, correct administration and scoring of CROMs is essential.…”