reliability

• problems with schizophrenia diagnostic systems

  both these tools have different diagnostic criteria’s: diagnosis is not consistent between different parts of the world dependent on the tool being used.

  This means one country may have diagnosed someone as normal while another place with the same symptoms may see them as Schizophrenic. 
• reliability


  the consistency of the findings or results of a psychology research study

  
  

  can psychiatrists agree on the same diagnosis when independently assessing patients
• do the types and sub-types of schizophrenia make it easier for diagnosis?

  no, because patients rarely fall into one category as theres a clear overlap of symptoms
• Beck (1961) 


  looked at inter-rater reliablilty between 2 psychiatrists considering the cases of 154 patients. Reliability (agreement) was only 54%- cannot be reliable for diagnosis
• cultural differences: Copeland et al (1971)

  description of patient given to 134 US and 194 British psychiatrists:

  • 69% of US diaganosed schizophrenia
  • 2% of UK diagnosed schizophrenia
• ROSENHAN "Being sane in insane places" Study 1:

  • involved 8 pseudo- patients located in different states
  • tried to gain admission by complaining of auditory hallucinations
  • 20 different hospitals selected
  • pseudo patient said they heard voices saying "empty", "hollow" & 'thud'
  • never found out by staff in 11/12 cases & admitted with a schiz diagnosis

  common for real patients to detect pseudo patients sanity

  length of hospitalisation: 7-52 (19 avg.)
• rosenhan study 2:

  aim: Seeing the tendency towards diagnosising the sane as insane could be reversed

  • Given results of stay 1, hospital was falsely informed that 1 or more pseudo patients would try gain admission in next 3 months
  • All staff asked to make judgements on 193 patients admitted for treatment
  • 83/193 actual parents confidently judged / suspected of being a pseudo patient by at least 1 staff
• What is a key issue in diagnosing schizophrenia?


  The reliability of schizophrenia diagnoses
• What have we learned about the reliability of schizophrenia diagnoses?


  It may be unreliable due to varying criteria and cultural differences
• What is a potential danger of an unreliable diagnosis of schizophrenia?


  It can lead to inappropriate treatment and stigma
• Self perception

  • Stigma leads to low self esteem
  • Loss of confidence
  • Increased anxiety

  Label becomes a self-fulfilling prophecy
• Relationships


  • Difficulty in socialising
  • Dependency on others
  • Creates strain on the family
• Employability


  • Few employers would take on a schizophrenia
  • Erratic behaviours
  • Unreliability
  • Time off needed for treatment
• What are the key points to discuss regarding the reliability of diagnosing schizophrenia?

  • Reliability issues: inter-rater reliability, cultural differences