Last reviewed: 6 Feb 2021
Last updated: 03 Feb 2021



History and exam

Key diagnostic factors

  • failure to give close attention to details or making careless mistakes in schoolwork, work, or other activities
  • difficulty sustaining attention in tasks or play activities
  • does not seem to listen when spoken to directly
  • does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace
  • often has difficulty organizing tasks and activities
  • avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort (such as schoolwork or homework)
  • often loses things necessary for tasks or activities (e.g., toys, school assignments, pencils, books, or tools)
  • easily distracted by extraneous stimuli
  • forgetful in daily activities
  • fidgets with hands or feet or squirms in seat
  • leaves seat in classroom or in other situations in which remaining seated is expected
  • runs about or climbs excessively during inappropriate situations
  • difficulty playing or engaging in leisure activities quietly
  • often "on the go" or often acts as if "driven by a motor"
  • often talks excessively
  • often blurts out answers before questions have been completed
  • often has difficulty awaiting turn
  • often interrupts or intrudes on others (e.g., butts into conversations or games)

Other diagnostic factors

  • mild mood symptoms (dysphoria, mood lability, irritability, boredom)
  • difficulty with peer interactions
  • low self-esteem
  • working memory (i.e., short-term memory) impairment
  • processing speed impairment (i.e., the rate at which information is dealt with)

Risk factors

  • family history of ADHD
  • male┬ásex
  • low birth weight
  • epilepsy
  • maternal nicotine use during pregnancy
  • maternal alcohol use during pregnancy
  • stress during pregnancy and labor
  • psychosocial adversity
  • lead exposure
  • traumatic brain injury
  • severe early deprivation
  • iron deficiency

Diagnostic investigations

Treatment algorithm


Associate Professor of Neurology and Pediatrics

Director, Pediatric Neuropsychiatry Program

Children's Hospital of Philadelphia




LWB has been reimbursed by Sunovion for participation in a Medical Advisory Board.

Dr Lawrence W. Brown would like to gratefully acknowledge Dr Kristin S. Russell, Dr Howard Y. Liu, and Dr Michael S. Jellinek, previous contributors to this topic. KSR, HYL, and MSJ declare that they have no competing interests.

Peer reviewersVIEW ALL

Assistant Professor

College of Health Professions

Temple University




BPD declares that he has no competing interests.

Academic Specialist Registrar

Academic Department of Paediatrics and Obstetrics and Gynaecology

Leeds University




MMH declares that he has no competing interests.

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