There is currently no single available tool for the diagnosis of attention-deficit hyperactivity disorder (ADHD), or hyperkinetic disorder (HKD). Formal diagnosis is made using evidence accumulated from the initial clinical assessment and medical classification systems.1,2 Formal assessment and diagnosis should only be made by appropriately qualified healthcare professionals, such as specialist psychiatrists, specialist nurses, or other qualified healthcare professionals, who have training and expertise in the diagnosis of ADHD in children, adolescents and/or adults.2

There are two main classification systems for diagnosing ADHD: the International Classification of Mental and Behavioural Disorders 10th revision (ICD-10), and the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders – 5th Edition (DSM-5TM), which replaced the previous version (DSM-IV) in 2013.3-5 The National Institute for Health and Care Excellence (NICE) and other clinical guidelines still refer to DSM-IV, and clinical trials initiated before the new edition also refer to DSM-IV.

The ICD-10 medical classification system refers to ADHD as HKD, a term widely used in Europe and included in European clinical guidelines developed with the European Network for Hyperkinetic Disorders (EUNETHYDIS).3 This classification system defines HKD as a persistent and severe impairment of psychological development, characterised by "early onset; a combination of overactive, poorly modulated behaviour with marked inattention and lack of persistent task involvement; and pervasiveness over situations and persistence over time of these behavioural characteristics".3


The DSM-5TM medical classification system for ADHD is published by the American Psychiatric Association and is used in the United States and the rest of the world. This classification system defines ADHD as "a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development".4

Regardless of which set of medical classification systems are used, the features of ADHD described are similar with the exception that the ICD-10 classification system requires that all three features - inattention, hyperactivity and impulsiveness - be present.3 HKD can be considered as a severe subset of the DSM-5TM-defined combined presentation of ADHD.2-4

These medical classification systems may be used alone or in conjunction with a range of rating scales, which often measure the impact of ADHD upon more specific areas of functioning or quality of life.1,2,6,7


View references

  1. Taylor E, Döpfner M, Sergeant J, et al. European clinical guidelines for hyperkinetic disorder – first upgrade. Eur Child Adolesc Psychiatry 2004; 13 Suppl 1: i7-i30.
  2. NICE (2008) Attention Deficit Hyperactivity Disorder: Diagnosis and Management of ADHD in Children, Young People and Adults. NICE clinical guideline 72. Available at www.nice.org.uk/CG72 [NICE guideline]. Last accessed May 2015.
  3. World Health Organization. The ICD-10 Classification of Mental and Behavioural Disorders. Available at: www.who.int/entity/classifications/icd/en/bluebook.pdf. Last updated 1993; 1: 1-263. Last accessed March 2015.
  4. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. Fifth edition. Washington, DC: American Psychiatric Association, 2013.
  5. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. Fourth Edition, Text Revision. Washington, DC: American Psychiatric Association, 2004.
  6. The Canadian Attention Deficit Hyperactivity Disorder Resource Alliance (CADDRA). Canadian ADHD Practice Guidelines (CAP-Guidelines) Third Edition. 2011. Available at: http://caddra.ca/practice-guidelines/download. Last accessed March 2015.
  7. Kooij SJ, Bejerot S, Blackwell A, et al. European consensus statement on diagnosis and treatment of adult ADHD: The European Network Adult ADHD. BMC Psychiatry 2010; 10: 67.

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Patient-centred management: every patient is different with unique needs – a Spanish perspective

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New eLearning Module on the burden and diagnosis of adult ADHD, supported by Professor Philip Asherson, is now available.

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This booklet has been created to assist with clinical assessment of adult patients with ADHD using DSM-5TM criteria and the ASRS checklist.

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ADHD is often a lifelong neurobehavioural disorder, which may persist from childhood into adulthood.

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Interactive module: Rating scales used for the assessment of ADHD prior to formal diagnosis

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Guidelines for the diagnosis, treatment and management of ADHD are available on an international, European and national level

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