Objective: This manuscript used evidence based statistical methods that estimate clinical treatment effect rather than whether groups were statistically different.
Background: The previously published blinded, randomised, controlled clinical trial comparing lateral fabellar suture (LFS) and tibial plateau leveling osteotomy (TPLO) was reported with a traditional analysis comparing groups. Although this was a well-designed study, evidence based statistical methods that estimate treatment effect would be helpful to the practitioner.
Methods: The effect size and number needed to treat (NNT) were calculated for the outcome measures with significant differences between groups using the data from a previously published randomised controlled clinical trial comparing TPLO and LFS in dogs with cruciate rupture.
Results: The effect size of the peak vertical force (PVF) at a trot, 1 year after TPLO over LFS, was moderate to high (0.71) with a NNT of 6. The NNT for satisfaction was 7.
Conclusion/Application: Based on this study, the effect size and NNTs are such that the clinical difference warrants recommending the TPLO over the LFS in large and giant breed dogs.