Definition and classification

The terms conduct disorder and antisocial behaviour are used to describe behaviour which deviates from generally accepted social norms, whereas the term delinquency is used to describe breaches of law. These definitions cover a wide spectrum of behavioural disorders ranging from frequent arguing, lying, running away and playing truant, through to violent crime (Sholevar, 1995; Quay and Hogan, 1999).

ICD-10 (WHO, 1992) distinguishes six types of ‘conduct disorder’ (F91). These are: ‘conduct disorder confined to the family context’ (F91.0), ‘socialized conduct disorder’ (F91.1), ‘unsocialized conduct disorder’ (F91.2), ‘oppositional defiant disorder’ (F91.3) and two remaining categories for ‘other’ and ‘unspecified’ conduct disorders.

F91.0 and F91.3 most frequently occur in younger children and may have a better prognosis. F91.1 and F91.2 are determined by the nature of the child's or adolescent's bonding, rather than whether the antisocial behaviour occurs alone or in a group.

Conduct disorders may also be classified under other diagnostic categories, such as ‘hyperkinetic conduct disorder’ (F90.1) and ‘mixed disorders of conduct and emotions’ (F92). Because of their specific features, these disorders usually require a different approach to treatment.

Epidemiology

Conduct disorders are common in childhood and adolescence. Depending on the sample, the reported incidence of conduct disorder ranges from 5 to 25% (Malmquist, 1991). One study (Remschmidt and Walter, 1989) which included an entire clinical sample (all in- and outpatients from a rural area with a total population of 450 000) found conduct disorder to be the most common diagnosis (20%) among 12–17-year-old patients.