Clinical Characteristics of Schizophrenia

Issues in the diagnosis and classification of schizophrenia | Delusions: which are bizarre beliefs that appear realistic to a person with schizophrenia, but they are not real. They can sometimes be paranoid delusions Experiences of control: the person with schizophrenia may believe they are under the control of different group’s e.g. alien invasion. Hallucination: are bizarre, unreal perceptions of the environment that are usually auditory (hearing voices), but may also be visual (seeing lights, objects or faces), olfactory (smelling things), or tactile (e.g. feeling that bugs are crawling on or under the skin). Disordered thinking: the feeling that thoughts have been inserted or withdrawn from the mind. In some cases the person may believe their thoughts are being broadcast so that others can hear them. Tangential, incoherent or loosely associated speech is used as an indicator of thought disorder. Affective flattening: a reduction in the range and intensity of emotional expression, including facial expression, voice tone, eye contact, and body language. Alogia: poverty of speech, characterised by the lessening of speech fluency and productivity, thought to reflect showing or blocked thoughts.

Unreliable symptoms: Klosterkötter et al. (1994) assessed 489 admissions to a psychiatric unit in Aachen, Germany, and found that positive symptoms were more useful for diagnosis than negative symptoms. Mojabi and Nicholson (1995) 50 senior psychiatrists in the US were asked to differentiate between ‘bizarre’ and ‘non-bizarre’ delusions, the inter-rata reliability was only around 0.40 showing that the central diagnostic requirement lacks sufficient reliability for it to be a reliable method of diagnosing schizophrenia.

Validity: Bental (1988) did a large review of all research into aetiology, prognosis and treatment and found that schizophrenia wasn’t a useful scientific category. Symptoms: Schneider (1959) listed first rank symptoms, he believed these are only found in schizophrenics, such as delusions and hallucinations. However, some of these are found in other disorders, such as depression and bipolar disorder. Ellason and Ross (1995) point out that people with dissociative identity disorder (DID) actually have more ‘schizophrenic’ symptoms than people diagnosed with schizophrenia. Gender differences in schizophrenia: Males are likely to develop symptoms in late teens/ early twenties. Females are likely to show symptoms in their 20’s. Males and females are equally likely to get schizophrenia. |