The aims of our study were to: (i) determine the prevalence of children aged 4 to 6 years with probable Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms in the Spanish population; and (ii) analyse the association of probable ADHD symptoms with sex, age, type of school, origin (native or foreign) and socioeconomic status in these children. | Prevalence of probable Attention-Deficit/ Hyperactivity Disorder symptoms: Result from a Spanish sample of children