When there is data on a sufficiently large number of dogs in a given line, a breeder can evaluate the risk for genetic disease transmission of dogs in that family. The evaluations of every single dog, whether show dog or pet, become an important source of data that will allow breeders to try and selectively eliminate the disease from their lines. OFA evaluates the x-rays submitted and rates the condition of the hips as Excellent, Good, Fair, or Dysplastic. They will not certify a dog before the age of 2 years. Follow up evaluations are not necessary unless a specific problem has been identified.
Owners have the option of submitting all results to the registry, or just the normal results.
PennHIP uses a different method for evaluating hip joints and hip laxity. Passive hip laxity refers to the degree of looseness of the hip ball in the hip socket when the dog's muscles are completely relaxed. Dogs may be evaluated as early as 16 weeks of age. Follow up evaluations are not necessary unless a problem has been identified. The GDC evaluates according to the hip extended method like OFA, but requires a pedigree of the dog to be submitted along with the x-ray.