A nurse is providing teaching to the parents of a 6-year-old child who is suspected to have attention deficit hyperactivity disorder (ADHD). Which of the following statements should the nurse make to describe the diagnostic process for ADHD?

"Blood tests and scans are typically used to confirm the diagnosis of ADHD."

"We can use a computer-based test to definitively diagnose your child with ADHD."

"Clinical manifestations of ADHD must be observed for at least three months to be considered for diagnosis."

"Diagnosis of ADHD primarily relies on the results of comprehensive diagnostic studies."