In 12 different countries spread over the whole world, both people with attention deficit disorder as well as healthy controls at all age levels are to be examined according to the usual criteria (DSM 5 or ICD 10) (a total of 800 patients and healthy persons). The diagnoses have to be created independent of the biological markers, whereby the marker-independent database comparisons are made available to the experts. In a second step, the neuroalgorhythms are given to the responsible medical specialists for the patient double-blinded as real neuroalgohythms or dummy algorhythms. The specialists must then qualify the obtained markers. After 12 months, both the patients and the healthy control subjects are examined again.