The ICD-10 Classification of Mental and Behavioural Disorders World Health Organization, Geneva, 1992

Contents

F91 Conduct Disorders

F91.0 Conduct Disorder Confined To The Family Context

F91.1 Unsocialized Conduct Disorder

F91.2 Socialized Conduct Disorder

F91 Conduct Disorders:
Conduct disorders are characterized by a repetitive and persistent pattern of dissocial, aggressive, or defiant conduct. Such behaviour, when at its most extreme for the individual, should amount to major violations of age-appropriate social expectations, and is therefore more severe than ordinary childish mischief or adolescent rebelliousness. Isolated dissocial or criminal acts are not in themselves grounds for the diagnosis, which implies an enduring pattern of behaviour.

Features of conduct disorder can also be symptomatic of other psychiatric conditions, in which case the underlying diagnosis should be coded.

Disorders of conduct may in some cases proceed to dissocial personality disorder (F60.2). Conduct disorder is frequently associated with adverse psychosocial environments, including unsatisfactory family relationships and failure at school, and is more commonly noted in boys. Its distinction from emotional disorder is well validated; its separation from hyperactivity is less clear and there is often overlap.

Diagnostic Guidelines
Judgements concerning the presence of conduct disorder should take into account the child's developmental level. Temper tantrums, for example, are a normal part of a 3-year-old's development and their mere presence would not be grounds for diagnosis. Equally, the violation of other people's civic rights (as by violent crime) is not within the capacity of most 7-year-olds and so is not a necessary diagnostic criterion for that age group.

Examples of the behaviours on which the diagnosis is based include the following: excessive levels of fighting or bullying; cruelty to animals or other people; severe destructiveness to property; firesetting; stealing; repeated lying; truancy from school and running away from home; unusually frequent and severe temper tantrums; defiant provocative behaviour; and persistent severe disobedience. Any one of these categories, if marked, is sufficient for the diagnosis, but isolated dissocial acts are not.

Exclusion criteria include uncommon but serious underlying conditions such as schizophrenia, mania, pervasive developmental disorder, hyperkinetic disorder, and depression.

This diagnosis is not recommended unless the duration of the behaviour described above has been 6 months or longer.

Differential diagnosis. Conduct disorder overlaps with other conditions. The coexistence of emotional disorders of childhood (F93.-) should lead to a diagnosis of mixed disorder of conduct and emotions (F92.-). If a case also meets the criteria for hyperkinetic disorder (F90.-), that condition should be diagnosed instead. However, milder or more situation-specific levels of overactivity and inattentiveness are common in children with conduct disorder, as are low self-esteem and minor emotional upsets; neither excludes the diagnosis.

Excludes:

• conduct disorders associated with emotional disorders (F92.-) or hyperkinetic disorders (F90.-)
• mood [affective] disorders (F30-F39)
• pervasive developmental disorders (F84.-)
• schizophrenia (F20.-)

F91.0 Conduct Disorder Confined To The Family Context:
This category comprises conduct disorders involving dissocial or aggressive behaviour (and not merely oppositional, defiant, disruptive behaviour) in which the abnormal behaviour is entirely, or almost entirely, confined to the home and/or to interactions with members of the nuclear family or immediate household. The disorder requires that the overall criteria for F91 be met; even severely disturbed parent - child relationships are not of themselves sufficient for diagnosis. There may be stealing from the home, often specifically focused on the money or possessions of one or two particular individuals. This may be accompanied by deliberately destructive behaviour, again often focused on specific family members—such as breaking of toys or ornaments, tearing of clothes, carving on furniture, or destruction of prized possessions. Violence against family members (but not others) and deliberate fire-setting confined to the home are also grounds for the diagnosis.

Diagnostic Guidelines
Diagnosis requires that there be no significant conduct disturbance outside the family setting and that the child's social relationships outside the family be within the normal range.

In most cases these family-specific conduct disorders will have arisen in the context of some form of marked disturbance in the child's relationship with one or more members of the nuclear family. In some cases, for example, the disorder may have arisen in relation to conflict with a newly arrived step-parent. The nosological validity of this category remains uncertain, but it is possible that these highly situation-specific conduct disorders do not carry the generally poor prognosis associated with pervasive conduct disturbances.