A03

• :) of the diagnosis of schizophrenia is its reliability.

  Research by Osório (2019) investigated whether different diagnosis clinicians would reach the same diagnosis and whether the same clinicians would reach the same diagnosis for the same individual on two occasions.

  The results showed excellent inter-rater reliability (+.97) and test-retest reliability (+.92) for the diagnosis of schizophrenia using the DSM-5.

  Therefore, this suggests that clinicians consistently reach the same diagnosis for individuals with schizophrenia, indicating a high level of consistency in its application.
• Point: One limitation of the diagnosis of schizophrenia is its validity.

  Evidence: Cheniaux (2009) had two psychiatrists independently assess the same 100 patients using ICD-10 and DSM-V criteria.

  Explain: They found that 68 were diagnosed under ICD-10 while 39 were diagnosed using the DSM-V.

  Link: Therefore, this raises concerns as the diagnosis of schizophrenia may not accurately assess the condition it intends to measure, leading to potential over- or underdiagnosis, depending on the diagnostic system used.
• weakness of diagnosis & classification is co-morbidity, when two or more conditions occur together.

  A review revealed the comorbidity rates for schizophrenia & other conditions, e.g. depression (50%), substance abuse (47%), PTSD (29%) and OCD (23%).

  => we're either bad at telling the diff btwn schizophrenia & other conditions or that if depression and schizophrenia occur simultaneously so often, it might be better seen as 1 condition.

  Therefore, => schizophrenia may not exist as a distinct condition & highlights challenges in accurately diagnosing it due to its association w other disorders.
• Point: A final limitation of schizophrenia diagnosis is symptom overlap with other conditions.

  Evidence: For example, positive symptoms like delusions and negative symptoms like avolition can be observed in both schizophrenia and bipolar disorder.

  Explain: This could mean that a person might be diagnosed with schizophrenia under the ICD classification, but receive a diagnosis of bipolar disorder according to DSM criteria.

  Link: Therefore, this highlights the complexity of diagnosing schizophrenia accurately and suggests potential limitations in its classification as a distinct disorder.