Final answer:
To diagnose ADHD, symptoms must be observed for at least 6 months and be inappropriate for the individual's developmental level. These symptoms should be present in two or more settings and cause interference or reduced quality of functioning in social, school, or work environments. A clinical diagnosis also differentiates ADHD from co-occurring conditions and takes into account the individual's full life context.
Step-by-step explanation:
To diagnose ADHD, practitioners follow guidelines established by recognized authorities such as the American Psychiatric Association. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), symptoms should be present for at least 6 months and they have to be inappropriate for the developmental level. Additionally, several symptoms should be present in two or more setting (e.g., at home, school, or work; with friends or relatives; in other activities), and there must be clear evidence that the symptoms interfere with, or reduce the quality of, social, school, or work functioning. It is also necessary for some symptoms to have been present before age 12 years.
Diagnosis of ADHD includes assessing symptoms such as inattention, executive functioning difficulties, impulsivity, and hyperactivity. For a clinical diagnosis, it's also important to distinguish ADHD from other comorbid conditions such as depression or obsessive-compulsive disorder (OCD), which can co-occur.
Furthermore, it is acknowledged that ADHD can present challenges not just in childhood but across an individual's lifespan, including education and workplace environments. Medication is a common treatment option, though there are considerations regarding its prescription and effectiveness over the long term.