Approach
The evaluation for attention deficit hyperactivity disorder (ADHD) should be comprehensive and include a thorough history from the patient and caregivers, collateral information from school, mental status examination (MSE), and consideration of neuropsychological testing.[90] The evaluation may be done by the primary care physician depending on experience, comfort level, and relevant service arrangements.
US guidance from the American Academy of Pediatrics recommends that the paediatrician or other primary care provider should carry out the initial assessment for ADHD for any child or adolescent between the aged of 4 and 18 who presents with academic or behavioural problems and symptoms of inattention, hyperactivity, or impulsivity.[90] However in practice, paediatricians will often refer patients with more complex problems to a specialist in psychiatry, neurology, or developmental behavioural paediatrics, particularly when a child has a possible comorbid conditions which they may not be experienced in diagnosing or treating.[90]
In other locations (e.g., the UK) national guidance recommends that the formal diagnosis and initial treatment of ADHD should only be carried out by a specialist, for example, child and adolescent psychiatrist, paediatrician, or other specialist in ADHD. However, UK guidance recommends that for some children with symptoms of moderate or less intensity, a watch and wait approach in primary care of up to 10 weeks may be appropriate following suspicion of the diagnosis, with provision of self-help, simple behavioural management, or parent support programmes.[91]
Diagnosis requires determination that DSM-5-TR criteria (or other diagnostic criteria e.g., ICD-11) have been met, including evidence of symptoms and impairment in more than one major setting (i.e., social, academic, or occupational).[1]
History
ADHD is a diagnosis made by clinical history that assesses behaviour in different aspects of the child's life:[90][91]
Source of history: parent and patient history should be supplemented by history from teachers and other carers such as coaches, tutors, or counsellors.[90] This should include narrative history (including learning patterns and peer interactions), grades, and rating scales. ADHD is more common in males, but may be underdiagnosed in females.[18] Problems that suggest ADHD can include school absences, academic difficulties, disruptive behaviours, inattention, and difficulties with peer interaction.
ADHD rating scales are important in eliciting history, and additional broadband behaviour checklists can help to identify comorbid conditions.
Some symptoms causing impairment must be present before 12 years of age.[1]
Focus of history: core symptoms of ADHD (specifically, the DSM-5-TR criteria), with attention to the age of onset, degree of impairment, and settings in which the symptoms occur.[1] It is important to note that symptoms vary significantly across settings and activities, becoming more prominent when the child is doing activities they perceive as boring or challenging (e.g., school work), and less prominent when doing activities they are more engaged with (e.g., video games).
Symptom history: this is elicited with open-ended questions and commonly used rating scales.
Gestational history, including maternal alcohol and substance use.
Family history: this includes history of ADHD, substance use, and other psychiatric illnesses.
Developmental history: includes information about pregnancy (maternal smoking, alcohol, and stress), birth history (including birth weight), and developmental milestones.
Past medical history: including any central nervous system trauma or infections as well as current medications. Possible lead exposure should be considered.
Psychosocial history: including tensions in the home (between parents, between parent and child) as well as detail regarding peer relationships, which are often impaired and may include a history of bullying.
Past psychiatric history: including past diagnoses and trauma history as well as assessment for comorbid mental and behavioural disorders including oppositional defiant disorder (ODD), conduct disorder, learning disabilities, mood disorders, and anxiety disorders.
Sleep and sleep hygiene history.
Mental status examination
The MSE should be performed as part of the diagnostic evaluation.[32] It includes appearance, alertness and orientation, ability to relate with the interviewer, speech, mood and affect, thought process, and estimation of cognitive ability. The MSE can assess for overt signs of ADHD including motor restlessness or hyperactivity, inattention, and working memory impairment. Additionally, it can elicit information about comorbid diagnoses as well as other mental disorders that would better explain the presenting symptoms. It is important to note that patients may often appear calm, quiet, and attentive in the structured, one-to-one setting of the doctor's surgery, and thus clinical presentation in this circumstance is not well correlated with diagnosis.
Rating scales used in diagnosis
The American Academy of Pediatrics (AAP) practice parameter suggests that clinicians incorporate one of the commonly used behaviour rating scales in their assessment.[90] Note however that ADHD cannot be diagnosed by rating scales alone.[92]
Narrowband scales assess only for ADHD, whereas broadband scales assess a variety of behaviour symptoms.[93] The AAP does not endorse a specific scale. In the author's experience, a brief scale is the preferred choice, as it reduces the burden on parents and teachers. The same scale can be used to follow response to treatment. A list of common rating scales is available, some free online.
Commonly used scales
The ADHD Rating Scale is an 18-item scale based on the DSM criteria for ADHD. It is useful both for diagnosing ADHD in children and adolescents and for measuring improvements with treatment.
The Vanderbilt Scale is a scale that assesses ADHD, comorbid conditions (including oppositional defiant disorder, conduct disorder, anxiety and depression), and performance. Vanderbilt ADHD diagnostic scales Opens in new window
SNAP-IV is included in many research trials, including the Multimodal Treatment Study of AD/HD (MTA). It is a 26-item scale that screens for hyperactive and inattentive forms of ADHD and for oppositional defiant disorder (ODD). SNAP-IV 26 - teacher and parent rating scale Opens in new window
The Child Behaviour Checklist (CBCL) can be used to evaluate a wide range of child behavioural problems, with the CBCL-Attention Problem (CBCL-AP) subscale used as a diagnostic tool for ADHD.[94]
Conners rating scales are the most widely accepted and include a long and short version for parents, teachers, and the child.
Neuropsychological tests
Because ADHD is considered a behavioural disorder, neuropsychological testing is not necessary for the diagnosis.[90] However, testing should be considered when it is important to differentiate, or identify as a co-occurring condition, between ADHD and learning disabilities (e.g., dyslexia, non-verbal learning disability), and disorders of language, visual-motor, or auditory processing. Failing to recognise a co-existing learning disability can result in inadequate response to medication, school failure, and low self-esteem.
In neuropsychological testing, patients with ADHD will generally have normal cognitive ability and academic achievement but will exhibit deficits in executive functions (those required to plan, prioritise, attend to, and inhibit behaviours) such as short-term (i.e., working) memory and processing speed (the rate at which information is dealt with).[95][96] Common tests of executive function include the Continuous Performance Test, Wisconsin Card Sorting Test, and Digits Backward test. If a learning disorder or a disorder of language, visual-motor, or auditory processing is suspected, appropriate neuropsychological testing can assess impairment in these areas.
Laboratory/neurological testing
Neither laboratory nor neurological testing is necessary in the work-up for ADHD if the medical history is unremarkable.[90] Some medical conditions can mimic the symptoms of ADHD; these include sleep disorders, traumatic brain injury, encephalopathy, lead exposure, and thyroid disorder. If these are suspected, specific tests should be ordered according to the medical condition and patients may be referred to the appropriate specialists.
Cardiovascular testing
A baseline cardiovascular assessment (including blood pressure and heart rate) is required prior to treatment initiation.[91] Children with pre-existing heart disease, symptoms suggestive of heart disease (e.g., syncope, palpitations, chest pain, post-exercise symptoms, heart murmur heard on auscultation, signs of heart failure) or a strong family history for sudden death should be referred to a cardiologist for examination before a stimulant trial.[90][91] If patients develop any cardiac adverse effects on stimulants, they should also be referred to a cardiologist. Referral to a paediatric hypertension specialist is recommended before starting medication for ADHD if blood pressure is consistently above the 95th centile for age and height for children and young people.[91] There is no need to obtain routine ECGs or echocardiograms for healthy patients receiving stimulants, but the American Heart Association recommends that it is reasonable to consider an ECG in selected children prior to stimulant treatment, depending on any positive findings suggestive of cardiovascular risk in the history and physical examination.[97]
Other medical assessment
Information about sleep patterns which suggest sleep apnoea is important as is a neurological assessment. If pharmacological treatment is being considered, weight and height measurement is required as a baseline. Referencing percentile charts and growth charts is recommended.
Use of this content is subject to our disclaimer