National Canine Research Council Summary and Analysis:
Fewer than half of the participants were able to correctly visually identify any breed in the dogs’ DNA analysis for 14 of the 20 dogs. Moreover, for 3 of the dogs whose predominant breed was agreed on by more than 50% of participants, this visual identification did not match any (major or minor) DNA breed identification. The experts were unable to agree with each other or with the DNA identification. For only 7 dogs (35%) could even half the observers agree on a predominant breed. Thus, in this sample of canine professionals, both inter-rater reliability and validity of visual breed identification were low.
The implications of these findings are incredibly important. Researchers and public policy makers should very carefully examine studies that link breed and behavior; if breed was reported without DNA confirmation or pedigree, the data cannot be considered reliable. Considering the potential severe implications for both the owners and dogs of specific breeds and/or types from Breed-Specific Legislation (e.g., bans, euthanasia, containment, and increased fees), agencies should exercise great caution when labeling a dog of unknown ancestry. If the lineage is unknown and DNA analysis unavailable, a “best guess” based on visual physical characteristics should not be made; it is reckless to do so given these data that demonstrate its unreliability. Moreover, researchers cannot responsibly conduct experiments nor cite studies that rely on visual identification for determining breed. Unless DNA analysis is conducted, or the dog’s parentage is documented by pedigree, specific breeds or breed groups should not be indicated.