[Prevalence, symptoms and distribution of oppositional defiant disorder]

The purpose of this work was to determine the epidemiological evolution of the Oppositional Defiant Disorder (ODD) in adolescents, using a sample of Secondary School students of the region of Campo de Gibraltar (Cadiz). The students' age ranged from 12 to 16 years old. Two evaluations were completed, the first one during the school year 2001-2002 and the second one in the school year 2006-2007. The sample comprised 2310 students in the first study and 2351 students in the second one. We used a comparative-selective approach. The results of the comparison revealed a prevalence ranging from 3.77% to 3.83% of students with this disorder, maintaining the main symptoms and with some changes in its distribution as a function of the school grade. Indeed, the data showed more cases in the final courses (1st study) in contrast with a higher concentration of cases in the initial courses (2nd study). With regard to the frequency of ODD by sex, we found that whereas in the earlier study (2001-2002), the relationship between boys and girls was 3.5:1, in the school year 2006/2007, the number of boys with ODD quadrupled the number of girls.