I would imagine most of the statistics are taken from pet insurance companies regarding pedigree verses mongrels/cross breeds, but I feel (and I dont want this taking the wrong way), ususally when a pedigree is bought the owners are given some form of puppy insurance, which in many cases is continued by the owners because they paid £..... for the pup, mongrels etc unless from a rescue dont usually come with insurance as pups, and in many cases unless something crops up the owners dont think of getting insurance. so to me the information given by the insurance companies may not be comprhehensive, and because many pedigrees have insurance the owners are more likely to take the dog to the vets and possibly claim over what may be considered minor things, where as someone that does not have insurance may take the attitude of lets wait and see and those health problems are obviously not recorded because the dog has not attended a vets or made a claim on the insurance?

Mo