3.3.1 Intro to Schizophrenia

• Schizophrenia

  • Mental disorder experienced by 1% of population
  • Diagnosed more in men, in the cities and in working class more than middle
• International Classification of Disease edition 10 = ICD 10
• Diagnostic & Statistical Manual edition 5 = DSM 5
• ICD 10 diagnosis requires two or more negative symptoms
• DSM 5 diagnosis requires one of the positive symptoms
• Positive symptoms = atypical experienced in a addition to normal experiences
• Negative symptoms = atypical experiences that represent a loss to normal experiences
• Positive Symptoms

  • Hallucinations
  • Delusions
• Negative Symptoms

  • Speech Poverty
  • Avolition
• Hallucinations = false sensory experiences that are not based on external stimuli
• Speech Poverty = the inability to speak clearly and fluently, resulting in difficulty in understanding speech
• Delusion = paranoia, irrational beliefs
• Avolition = a lack of motivation to do something, a lack of desire to do something; apathy
• Strength of Diagnosis of Schz : Reliability

  • Consistency with Diagnosis
  • Osorio et al (2019)
  • Inter-rater = same diagnosis for same individual (+0.97)
  • Test-retest = 1 clinician has same diagnosis on 2 occasions (+0.92)
• Weakness of Diagnosis of Schz : Validity

  • Criterion validity
  • Cheniaux et al (2009)
  • ICD = 68%; DSM = 39%
  • Under & Over diagnosis
• Weakness of Diagnosis of Schz : Co-morbility

  • Schz diagnosed with other conditions (depression, substance abuse)
  • Buckley et al
  • 1/2 diagnosed with Schz had depression or substance abuse
  • Schz may not be a distinct condition
• Weakness of Diagnosis of Schz : Symptom Overlap

  • Overlap with other conditions; schz & bipolar disorder/depression (avolition & delusions)
  • Hard to distinguish Schz as its own condition
• Weakness of Diagnosis of Schz : Gender Bias

  • Women under diagnosed
  • Cotton et al (2009)
  • Closer relationships so they get more support
  • Underdiagnosis & less treatment for women
• Weakness of Diagnosis of Schz : Culture Bias

  • Haiti = hearing voices = communicating with ancestors
  • Escobar (2012)
  • Overinterpretation of symptoms in Black British People
  • Discrimmination in culturally biased system