intro to schizophrenia

• Classification of mental disorder ?

  The process of organising symptoms into categories based on which symptoms frequently cluster together
• Schizophrenia ?

  A severe mental disorder where contact with reality and insight are impaired, an example of psychosis
• Positive symptoms of schizophrenia ?

  Atypical symptoms experienced in addition to normal experiences. They include hallucinations and delusions
• Hallucinations ?

  A positive symptom of schizophrenia. sensory experiences that have either no basis in reality or are distorted perceptions of things that are there
• Delusions ?

  A positive symptom of schizophrenia. They involve beliefs that have no basis in reality, for example, a person believes that they are someone else or that they are the victim of a conspiracy
• Negative symptoms of schizophrenia?

  Atypical experiences that represent the loss of a usual experience such as a loss of clear thinking or a loss of motivation.
• Speech poverty ?

  A negative symptom of schizophrenia. It involves reduced frequency and quality of speech.
• Avolition ?

  A negative symptom of schizophrenia. It involves lass of motivation to carry out tasks and results in lowered activity levels
• Co-morbidity ?

  The occurrence of two disorders or conditions together for example a person has both schizophrenia and a personality disorder Where two conditions are frequently diagnosed together it calls into question the validity of classifyung the two disorders separately.
• Symptom overlap?

  Occurs when two or more conditions share symptoms. Where conditions share many symptoms this calls into question the validity of classifying the two disorders separately
• One strength of the diagnosis of schizophrenia?

  P - is its reliability

  E - A psychiatric diagnosis is said to be reliable when different diagnosing clinicians reach the same diagnosis for the same individual (inter-rater reliability) and when the same clinician reaches the same diagnosis for the same individual on two occasions (test-retest reliability). reliability for schizophrenia diagnosis was low but this has now improved. Osório et al. report excellent reliability for the diagnosis of schizophrenia in 180 individuals using the DSM-5, Pairs of interviewers achieved inter-rate reliability of +97 and test-retest reliability of +92.

  L - can be reasonably sure that the diagnosis of schizophrenia is consistently applied.
• One limitation of the diagnosis of schizophrenia ?

  P - is its validity.

  E - One way to assess validity of a psychiatric diagnosis is criterion validity. Cheniaux et al. (2009) had 2 psychiatrists independently assess the same 100 clients using ICD-10 and DSM-IV criteria and found that 68 were diagnosed with schizophrenia under the ICD system and 39 under DSM.

  E - suggests that schizophrenia is either over or underdiagnosed. suggests that criterion validity is low.

  CA- the Osório et al. study reported above there was excellent agreement between clinicians when they used two measures to diagnose schizophrenia both derived from the DSM system.

  so the criterion validity for diagnosing schizophrenia is actually good provided it takes place within a single diagnostic system.
• Another limitation of schizophrenia diagnosis ?

  P - co-morbidity with other conditions.

  E - If conditions occur together a lot of the time then this calls into question the validity of their diagnosis and classification because they might actually be a single condition. Schizophrenia is commonly diagnosed with other conditions. For example, one review found that about half of those diagnosed with schizophrenia also had a diagnosis of depression or substance abuse.

  L - This is a problem for classification because it means schizophrenia may not exist as a distinct condition, and is a problem for diagnosis as at least some people diagnosed with schizophrenia may have unusual cases of conditions like depression.
• A further limitation of schizophrenia diagnosis?

  P - is the existence of gender bias.

  E - Since the 1980s men have been diagnosed with schizophrenia more commonly than women. One possible explanation for this is that women are less vulnerable than men, perhaps because of genetic factors. However it seems more likely that women are underdiagnosed because they have closer relationships and hence get support. This leads to women with schizophrenia often functioning better than men.

  L - this under-diagnosis is a gender bias and means women may not therefore be receiving treatment and services that might benefit them.
• A further limitation of schizophrenia diagnosis?

  P - is the existence of culture bias.

  E - Some symptoms of schizophrenia, particularly hearing voices, have different meanings in different cultures. For example in Haiti some people believe that voices actually are communications from ancestors. British people of African-Caribbean origin are up to 9 times as likely to receive a diagnosis as white British people, although people living in African-Caribbean countries are not, ruling out a genetic vulnerability. most likely explanation for this is culture bias in diagnosis of clients by psychiatrists from a different cultural background. leads to an over-interpretation of symptoms.

  L - British African-Caribbean people may be discriminated against by a culturally-biased diagnostic system.
• A final limitation of schizophrenia diagnosis ?

  P - symptom overlap with other conditions.

  E - considerable overlap between the symptoms of schizophrenia positive symptoms. For example, both schizophrenia and bipolar disorder involve positive symptoms and negative symptoms. this suggests that Schizophrenia and bipolar disorder may not be two different conditions but variations of a single condition. in terms of diagnosis it means that schizophrenia is hard to distinguish from bipolar disorder. As with co morbidity, symptom overlap means that schizophrenia may not exist as a distinct condition and that even If it does its hard to diagnose.

  L - So both its classification and diagnosis are flawed.