highly significantp = 3 × 10 −5
Within the case group, a Jonckheere–Terpstra test for trend (based on 100,000 permutations) revealed a highly significant increasing trend across the three age strata (puppy, juvenile, adult; JT = 166.5, p = 3 × 10 −5 ) with the median VBI increased from 0.48 (puppy) to 0.55 (juvenile) and 0.57 (adult).