ebook_ADHD2019_engl.

The World Federation of ADHD Guide 43 ASSESSMENTAND DIAGNOSTIC CLASSIFICATION SYSTEMS The diagnosis of ADHD is established clinically, based on criteria defined by diagnostic classification systems such as DSM and ICD. Core features of the di- sorder are developmentally inappropriate symptoms of inattention, hyperactivity, and impulsivity. Probably, ICD-11 5 will abandon the operational criteria approach relying only in a prototype presentation ( https://icd.who.int/ ) . A synthesis of the operational criteria of the DSM-5 6 for ADHD can be found in Box 3.1. The structure of the operational criteria can be divided in a preamble and the five criteria: symptom list, age-of-onset, pervasiveness, impairment and situations that might exclude the diagnosis. THE PREAMBLE The key elements in the preamble are: (a) persistent pattern of symptoms; (b) symptoms interfere with or reduce the quality of functioning or development; (c) symptoms inconsistent with developmental stage and not merely a manifestation of intellectual disabilities or ODD symptoms; (d) a lower symptom threshold for diagnosing ADHD in adults (addressed in the next sub-section – list of symptoms). The DSM-5 requires a persistent pattern of symptoms to make an ADHD diagnosis. A specific duration of at least 6 months is suggested. This is not an evi- dence-based criterion. We are not aware of studies addressing the validity of this criterion (i.e. whether the threshold to define persistence could equally be 1, 3, 6, 12 months or more). However, the rationale of the criterion is based on research data suggesting a stable biological vulnerability for the disorder, and based on the recognition that ADHD cardinal symptoms are non-specific and may arise as a short-term response to environmental stressors like family problems or higher school demands. Clinicians should therefore carefully discuss each symptom with patients and their families, considering only those that are frequently present in their daily lives, and have a stable trait-like quality, as positive. This is the reason that different DSM versions have always kept the word ‘ often ’ in front of each one of the 18 symptoms. A failure to set a common understanding with the family on a culturally acceptable definition of what is considered to be frequent makes it impossible to determine the persistent pattern of symptoms requested in the DSM-5. 7 The symptoms must be inconsistent with developmental stage of the individual under assessment. Previous research clearly identifies ADHD as a dimensional di- sorder. Thus, clinicians are faced with the difficult task of defining the boundaries of what a typical behavior is for an individual and when a pathological threshold