[The prevalence of attention deficit hyperactivity disorder]

Hyperactivity is a common, genetically-based disorder in childhood in which a number of neurological and psychological factors that give rise to attentional disorders, impulsiveness and motor overactivity are involved.

The prevalence rate of attention deficit hyperactivity disorder (ADHD) is a controversial matter. Although the DSM-IV gives an interval of between 3 and 5%, which is probably the value that is most widely accepted by the scientific community, there is in fact a very high degree of variability. According to different authors, an interval of 2-30% is obtained in the general population. In Anglo-Saxon countries the most commonly accepted prevalence of this entity is 5%, but few studies have been conducted in our country. In an epidemiological study with a community-based sample extracted by multistage, stratified sampling in school-age children on the island of Majorca, the estimated prevalence of ADHD was 4.7%. The authors consider aspects concerning the prevalence of ADHD and subtypes by ages, sex, in both the clinical and community environments.

The analysis of these data will enable us to compare the different evaluation methods used and to draw conclusions about screening and early detection methods.