diagnosis and symptoms

• positive symptoms

  additional experiences that someone doesn't usually have

  • hallucinations - unusual experiences linked to one or more sense eg. seeing, hearing or feeling things that aren't there
  • usually auditory or visual but can be any sense
  • delusions - irrational beliefs that a person has about something and seem very real to the person
  • delusions of persecution - a person believes something or someone is out to hurt them
  • delusions of grandeur - a person believes they are powerful or important
• negative symptoms

  symptoms involving the loss of usual abilities and experiences

  • avolition - a person fails to engage in a goal-directed activity and stops making an effort to do anything, they show no motivation
  • alogia - speech poverty, a reduction in the amount or quality of their speech
  • it may lack frequency, fluency or involve brief responses
• diagnosis

  there are two manuals for diagnosing mental health disorders

  • dsm-5 - american manual, requires two or more symptons lasting at least six months or one severe symptom for at least a month
  • icd-11 - world health organisation manual, can be diagnosed with two or more negative symptoms that have been present for a month
• prognosis

  the rule of thirds -

  • 1/3 recover more or less completely
  • 1/3 experience episodic impairment
  • 1/3 experience chronic decline
  • 14% of people with schizophrenia die by suicide or attempt suicide

  with treatment about 60% of patients manage a relatively normal life

  • there is a misconception created by the media that people with schizophrenia are violent
  • 8% of schizophrenic patients commit serious acts of violence in a year
• validity


  whether or not a diagnosis of schizophrenia measures what it is intended to, do people diagnosed with it actually have it?

  • criterion validity - do different assessment systems arrive at the same diagnosis for an individual
  • cheniaux - 2 psychiatrists independently diagnosed 100 profiles using both icd and dsm criteria and found people were much more likely to be diagnosed according to the icd, which suggests either the icd overdiagnoses or the dsm underdiagnoses
  • there is no way of knowing which is accurate
• reliability

  consistency, the extent of agreement between psychiatrists/manuals on diagnoses

  • cheniaux - 2 psychiatrists independently diagnosed 100 profiles using both icd and dsm criteria and found poor reliability between both manuals and psychiatrists
  • pyschiatrist 1 - 26 according to dsm and 44 according to icd
  • psychiatrist 2 - 13 according to dsm and 24 according to icd
  • this may be the case because the dsm is much more restrictive and requires more symptoms over a long period whereas the icd is less strict about what constitutes as schizophrenia
  • can't explain inter-rater issues
• issues affecting validity and reliability

  1. comorbidity - having two or more mental health issues at the same time
  2. symptoms overlap - different mental health issues have symptoms in common
  3. gender bias - differences in rate of diagnosis between the sexes
  4. cultural bias - differences in rate of diagnosis between ethnic/cultural groups
• comorbidity

  having two or more mental health issues simultaneously

  • creates questions around whether the two are separate conditions
  • also questions if we are accurately able to tell the difference
  • has implications in treatment
  • suggests labels may create conclusion and shouldn't be used

  buckley - studied comorbidity for schizophrenia

  • 50% comorbiditiy with depression
  • 47% comorbidity with substance abuse
  • 29% comorbidity with ptsd
  • 23% comorbidity with ocd
• symptoms overlap

  different mental health conditions have symptoms in common

  • creates questions about whether they are separate illnesses eg. schizophrenia and bipolar may be the same condition presenting differently
  • means patients may not be diagnosed with the right disorder
  • implications for treatment - may be better to treat symptoms not disorders

  schizophrenia shares many symptoms with bipolar disorder such as delusions and hallucinations as well as avolition, and shares its negative symptoms with depression
• gender bias

  differences in rates of diagnosis based on sex

  • are men genetically more vulnerable to schizophrenia - no evidence to prove so
  • women may function better than men, or be better at concealing their symptoms
  • women may be more likely to seek help before their symptoms develop into schizophrenia
  • psychiatrists may hold bias that leads them to perceive men as more likely to have it - the rate of diagnosis of schizoaffective disorder is the same between genders

  longenecker - since the 1980s men have been more likely to be diagnosed with schizophrenia
• cultural bias

  differences in rate of diagnosis between cultural/ethnic groups - african americans are more likely to be diagnosed (2.1%) than white americans (1.4%)

  • not due to genetic vulnerability - no evidence
  • symptoms of hearing voices may be misinterpreted as signs of mental illness when in reality it is part of their culture
  • afro-caribbean immigrants are more likely to live stressful lives, live in poverty and abuse substances