title: Signalment factors, comorbidity, and trends in behavior diagnoses in dogs: 1,644 cases (1991-2001).
abstract: OBJECTIVE
  To determine trends in behavior diagnoses; assess the relationship between diagnoses and age, sex, reproductive status, and breed; and evaluate associations between diagnoses within the same dog (comorbidity).
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  1,644 dogs.
  
  
  METHODS
  Medical records of dogs evaluated for behavioral problems were reviewed for breed, sex, reproductive status, consultation year, birth date, and diagnoses.
  
  
  RESULTS
  Numbers of dogs with aggression, anxiety, and unruly behavior increased over the course of the study, as did the total number of dogs evaluated for behavioral problems. In general and for aggression, Dalmatians, English Springer Spaniels, German Shepherd Dogs, and mixed-breed dogs were evaluated more often than expected, whereas Labrador Retrievers and Golden Retrievers were evaluated less often than expected. Labrador Retrievers were also underrepresented for anxiety, whereas mixed-breed dogs were overrepresented. Males were overrepresented except for interdog aggression, anxieties, and phobias, whereas females were overrepresented for phobias. Dogs with phobias were evaluated at a median age of 6.5 years, compared with dogs with other problems (median age, 2.5 years). A mean of 1.6 diagnoses/dog was observed, with certain diagnoses clustered.
  
  
  CONCLUSIONS
  Results suggested that in dogs, behavioral problems changed over the course of the study; age, sex, and breed distributions varied among diagnoses; and certain diagnoses were likely to occur together.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Bamberger
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Houpt
mesh_terms: D000367:Age Factors; D000374:Aggression; D000818:Animals; D001007:Anxiety; D001522:Behavior, Animal / Q000502:physiology*; D016000:Cluster Analysis; D015897:Comorbidity; D004283:Dog Diseases / Q000453:epidemiology* / Q000523:psychology; D004285:Dogs / Q000502:physiology* / Q000523:psychology*; D005239:Fear; D005260:Female; D008297:Male; D010375:Pedigree; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution