The following explanatory variables were included in the analysis: gender, breed, age of arrival to a new home (in weeks), place of birth (at mother's home / at breeder) amount of socialisation, number of children in the
household, number of adults, number of dogs in the
household, number of other diagnosed diseases, the time the dog has to spend alone during a
normal day, amount of daily exercise, amount of
activities done with the dog, dietary supplements, neutering status and type of food.