Schizophrenia Flashcards
What are the two main systems for classification of schizophrenia ?
the DSM 5 - American
the ICD 11 - world health organisations classification
Define positive symptoms of SZ. What two types plus two additional bonus positive symptoms?
They are additional experiences beyond those of ordinary existence.
1)Hallucinations - unusual sensory experiences. Some are related to the environment, some bear no relationship
2) Delusions - irrational beliefs that are resistant to confrontation of the truth.
3) Psychomotor disturbances: rocking back and forth etc
4)Catatonia - staying in position for hours/days
What forms of delusions can people with SZ get?
1)Delusions of persecution: the belief that others want to harm, threaten or manipulate you
2)Delusions of grandeur: the idea that you are an important individual, even God-like and have extraordinary powers. One of the most common types of this delusions is the belief that they are Jesus
3)Delusions of control: may belief that they are under the control of an alien force that has invaded their mind and/or body.
Define negative symptoms. What are the two types of negative symptoms?
They involve the loss of usual abilities and experiences.
1) Avolition (apathy): finding it difficult to begin or keep up with goal-direct activities. Sufferers of SZ often have reduced motivation to carry out a range of activities
2) Speech poverty (agolia): changing patterns in speech, this is because of the reduction in the amount and quality of speech in SZ. This can be manifested as a delay in the sufferers’ responses during conversations.
(Andreason 1982) What are the three signs of avolition?
1) Poor hygiene and grooming
2) Lack of persistence in work or education
3) Lack of energy
What does reliability mean?
Means there is good consistency over time between the individuals (the raters) who are using the system to rate patients. If two therapists often disagree in their diagnosis of patients then this would suggest a low reliability for that system.
What does validity mean?
Means that the diagnostic system assesses what it claims to be assessing. In the case of SZ, it means that patients who are diagnosed as sufferers of SZ do actually have that mental disorder.
Essay plan for discuss the reliability and/or validity in relation to the diagnosis and classification of schizophrenia (8 marks)
A01:
-outline validity and reliability in relation to SZ
-How co-morbidity and symptom overlap can impact the reliability and validity
A03:
(-)lack of validity - Rosenhan - what did he do? what did he find? +low pop validity
(-)Lack of reliability - Cheniaux - what did he find?
(-)Lack of reliability Rosenhan
8 confederate pseudopatients to 12 diff hospitals. Complained of hearing voices saying “empty”, “hollow” and “thud”. Once on the ward stopped pretending symptoms and behaved normally. Staff diagnosed 11 pseudopateints with sz and one with manic-depression, staff never detected their sanity. The behaviour of pseudopateints being misinterpreted by staff puts into question the validity of the measure (ICD/DMS) for SZ and that the staff are not comfortable using the diagnostic tools due to symptom overlap. The validity of the diagnosis is weather the diagnosis is correct and leads to successful treatment and thus there is an argument for validity.
(-)Lack of reliability - Cheniaux
There is evidence to suggest that the inter-rater reliability(IRR) in the diagnosis of SZ is poor. For example, Cheniaux (2009) asked 2 psychiatrists to independently diagnose 100 patients using both DSM and ICD criteria. IRR was poor, with one psychiatrist diagnosing 26 with SZ according to DSM and 44 according to ICD, and the other diagnosing 13 according to DSM and 24 according to ICD. This inconsistency between MH professionals indicates poor reliability in the diagnosis of SZ because diff professionals are not arriving at the same diagnosis for each patient.
2 further evauation points about the diagnosis of scizophrenia other than lack of valididty and lack of reliability
(-)symptom overlap
(-)co-morbidity
