Evaluating ADHD Assessment for Dogs: A Replication Study

SIMPLE SUMMARY: Attention-Deficit/Hyperactivity Disorder (ADHD) is among the most common human neurodevelopmental disorders, characterized by symptoms of inattention, hyperactivity, and impulsivity. Scientists and veterinarians report that—comparably to human children—family dogs can exhibit behaviors similar to symptoms of ADHD. In the present study, we aimed to review the properties of the questionnaire used so far on dogs to test whether it is a reliable tool to assess ADHD-like behaviours, and if it is suitable to detect diagnosable individuals. Similarly to human research, we involved experts (dog trainers) alongside the owners in the evaluation process and compared their ratings. Consistent with earlier results, we could replicate the factor structure of the questionnaire, and item and subscale scores showed high temporal stability. Agreement between owner and trainer ratings were fair (inattention subscale) and moderate (hyperactivity/impulsivity subscale). Three ambiguous items were identified using a version where an ‘I do not know’ answer was also available. Our findings confirmed that the questionnaire is a reliable tool to assess ADHD-like behaviour in dogs. However, to establish whether there are individual dogs diagnosable with ADHD, similarly to human questionnaires, expert ratings and items assessing functional impairment in the daily life of the dogs should be included. ABSTRACT: The family dog, in its natural environment, exhibits neuropsychological deficits redolent of human psychiatric disorders, including behaviours similar to human Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms. For dogs, Vas and colleagues developed a 13-item questionnaire to measure inattention and hyperactivity/impulsivity (Dog ARS; 2007). We re-assessed, in a large sample of dogs (N = 319), psychometric properties of the Dog ARS, to identify possible limitations as a basis for further development. We examined the cross-study stability of factor structure and 40-day temporal stability of item and subscale scores and compared owner-report with expert (dog trainer)-report (n = 86), paralleling human parent/teacher assessments. To identify ambiguous items, we administered a modified version (including “I don’t know” options, N = 520) to a different sample. We could replicate the factor structure with evidence of good internal consistency and test–retest reliability of both subscales. Agreement between owner and trainer ratings was fair (inattention) and moderate (hyperactivity/impulsivity). Three ambiguous items were identified. Overall, we claim that the Dog ARS is a reliable tool to assess ADHD-like behaviour in dogs, but in its current form, it is not suitable to detect diagnosable individuals, as it does not comprise items assessing functional impairment, and also, the inclusion of owner-expert ratings in the evaluation process would be necessary.