Studies using standardized diagnostic interviews report particularly high comorbidity rates in children and adolescents with schizophrenia. However, the volume of symptoms other than those required to make the diagnosis of schizophrenia remains the subject of controversy. The question is to consider these symptoms as an additional diagnosis, or as associated characteristics. Be that as it may, the frequency of these symptoms highlights the problems of differential diagnosis encountered in early-onset schizophrenia, particularly during the initial phase of the disorder.
