Diagnosis and Classification of SZ
Contact with reality and insight are impaired. 1% of population suffer from it.
Classification- Diagnostic and Statistics Manual (DSM 5)- Subtypes dropped for DSM 5
Symptoms
Positive- In addition to normal life.
Negative- Lose of usual activities
Hallucinations- Unusual sensory experiences. Can either resemble or not events in the environment. Most commonly voices in the head.
Delusions- Irrational beliefs.
Of grandeur- You are a super important figure
Of control- You are under control of aliens
Of persecution- You are about to be attacked
Avolition- Difficult to keep up with goal directed activity. Often involves lack of motivation
Speech Poverty- Reduction in amount and quality of speech.
EVALUATION
Reliability- Can be measured in 2 ways, test retest and inter rater reliability (between multiple studies). Found Kappa score of 0.46, considered good if above 0.7.
Evidence for this from Rosenham- used pseudopatients and instructed them to fake one type of positive symptom of schizophrenia. All were diagnosed.
Copeland conducted a study on over 100 US and UK psychiatrists. Gave a description, 69% of US diagnosed, 2% of UK did. Shows different countries expectations on schizophrenia
Voices in head varied culturally, Luhrman found in India and African countries, voices were often playful or helpful, some others were spiritual, where as no US people found voices beneficial.
Validity- Truthful value
Co-morbidity- Having two or more diagnosed conditions. Often SZ is coupled with depression, Buckley found rates to be 50%
Symptom Overlap- Symptoms appropriate for other conditions. Ellason and Ross found patients suffering from dissociative identity disorder (DID) had more symptoms of SZ than a schizophrenic.
Broverman studied on gender bias, mentally healthy men associated with mentally healthy adult, so women perceived as less healthy. Furthermore, Loren and Powell gave 290 male and female psychiatrists descriptions, 56% gave diagnosis when described as male, where as 20% did for female.