classification and issues with reliability

• Schizophrenia is a type of psychosis characterised by severe disruption to cognition and emotion which affects thinking, perception and sense of self. 
• The DSM-5 is a diagnostic manual used to diagnose an individual with schizophrenia. It includes three criteria. Criterion a is when an individual needs to have two of the following symptoms: hallucinations, delusions, disorganised speech and catatonic behaviour. Criterion b is when an individual has a decline in social and occupational behaviour. Criterion c is when an individual needs to have symptoms occurring for at least 6 months. 
• Positive symptoms of schizophrenia is when there is an excess or distortion of normal behaviour. Delusions are a positive symptom of schizophrenia; irrational beliefs that seem real to the participant, but they aren’t. They can be persecutory or grandeur. Hallucinations are unreal perceptions of what is real and are usually visual or auditory e.g. hearing voices that aren’t there. 
• Negative symptoms are a loss or reduction in normal function and can lead to reduced ability to cope with everyday life. Negative symptoms include speech poverty, reduction in amount or quality of speech produced in a given time, or affective flattening which is reduced emotional expression. 
• A03

  +One strength of the diagnosis of schizophrenia is that is has high diagnostic reliability. This is when multiple clinicians can diagnose the same participant with the same condition. Supportive research provides evidence to suggest that the DSM-5 is a reliable and useful diagnostic manual. Osorio et al reported 180 patients that were diagnosed using the DSM-5 and found an inter observer reliability rate of +0.97 and a test retest rate of +0.92. This therefore shows the accuracy of the DSM-5 in reliably diagnosing patients with schizophrenia
• A03

  -However, one diagnosis issue is the issue regarding co morbidity - when two conditions can co-exist at the same time. This is an issue in schizophrenia as it is harder to accurately diagnose participants as solely having schizophrenia as there may be another mental disorder involved. Support for this comes from swets et al who found 12% of patients with schizophrenia also met the diagnostic criteria for ocd. Therefore, this reduces the validity and reliability of the diagnosis of schizophrenia as a multitude of factors have to be considered to ensure there is not a false diagnosis made.
• A03

  • gender bias involved in the diagnosis of schizophrenia. Men are more likely to be diagnosed with schizophrenia compared to women, at a rate of 1.4 to 1. This may be due to genetic vulnerability. However, Cotton et al suggested that women are more likely to foster closer relationships with friends/family , using them as a support system instead of getting a clinical diagnosis. This means they can have a lower quality of life, as they are not getting the best level of help needed for such a serious condition. This means condition can worsen due to this lack of diagnosis worsening condition
• • The ICD-10 classified schizophrenia according to whether two or more negative symptoms were present
  • The ICD-11 classifies schizophrenia according to whether at least two positive or negative symptoms are present in the patient
  • Both the ICD-11 and the DSM-5 state that psychotic symptoms should be present in the patient for at least one month for a diagnosis of schizophrenia to be made, with the DSM-5 requiring that these symptoms continue for up to 6 months