diagnosis and classification

Question 1

what aspects of functioning are affected by sz?

Answer 1

it affects a persons language, thought, perception and even their sense of self.

Question 2

what is schizophrenia?

Answer 2

a severe mental disorder characterised by a profound disconnection from reality, involving a disruption of cognition and emotion.

Question 3

at what age is sz typically diagnosed?

Answer 3

between the ages of 15-35.

Question 4

who is more commonly affected in sz?

Answer 4

more commonly diagnosed in men in cities and the working population.

Question 5

how prevalent is sz?

Answer 5

it ranks among the top 10 causes of disability worldwide and affects about 1% of the population at some point int their lives.

Question 6

what is meant by a positive symptom?

Answer 6

atypical symptoms experienced in addition to normal experiences, e.g. hallucinations.

Question 7

what is meant by a negative symptom?

Answer 7

atypical symptoms that represent loss to normal experiences, e.g. speech poverty.

Question 8

what are positive symptoms of sz?

Answer 8

• hallucinations. they can be heard, seen, felt or tasted. voices can be heard.
• delusions. irrational beliefs that seem reasonable to the person. can take range of forms.

Question 9

what are the negative symptoms of schizophrenia?

Answer 9

• avolition. can’t keep up with goal desired activity.
• speech poverty (alogia). lessening of speech fluency. delay in conversation.

Question 10

what did Andreasen identify as the three signs of avolition?

Answer 10

• poor hygiene
• lack of persistence in work
• lack of energy

Question 11

how is schizophrenia diagnosed and why is it problematic?

Answer 11

• it does not have one defining characteristic. it is a cluster of seemingly unrelated symptoms.

Question 12

what is a classiification system?

Answer 12

it collects the symptoms of a disorder.

Question 13

how are classification systems used in psychiatry?

Answer 13

they use this list of symptoms to diagnose the disorder.

the 2 major systems for the classification of mental disorders are:
- ICD-10
- DSM-5

Question 14

which symptoms are required for an ICD-10 based diagnosis of sz and how long?

Answer 14

2 or more negative symptoms for one month are sufficient for a diagnosis.

Question 15

what subtypes does the ICD-10 recognise?

Answer 15

• paranoid: powerful delusions and hallucinations but few other symptoms.
• hebephrenic: involves primarily negative symptoms.
• catatonic: involves disturbance to movements.

Question 16

are positive symptoms required for ICD-10 diagnosis?

Answer 16

no

Question 17

which symptoms are required for a diagnosis of schizophrenia using DSM-V and for how long?

Answer 17

two or more of the following for at least one month or longer. one must be positive.

1. delusions
2. hallucinations
3. disorganised speech
4. grossly disorganised or catatonic behaviour
5. negative symptoms like diminished emotional expression

Question 18

what are the main differences between ICD-10 and DSM-V?

Answer 18

DSM states some signs must be present for 6 months but in ICD but one month is enough.

DSM states there must be 1 positive symptom, ICD = two negative symptoms are enough.

Question 19

what is the impact of the differences in the classification systems?

Answer 19

• poses challenges with reliability and validity.

Question 20

what is reliability?

Answer 20

the consistency of the diagnostic instrument to assess the severity of sz symptoms.

Question 21

what is validity?

Answer 21

the extent to which a diagnostic represents something that is real and distinct from other disorders.

also that ICD-10 and DSM-V are measuring what they are meant to measure.

Question 22

how do the terms reliability and validity apply to schizophrenia?

Answer 22

DSM and ICD are used in different parts of the world – so one patient may get a different diagnosis depending which country they are in.

• poses issues with reliability.
  Diagnosis is subjective and therefore different clinicians may diagnose different even using the same manual e.g. less likely to be diagnosed in African cultures.

Question 23

what study investigated the reliability of diagnosis in sz?

Answer 23

Rosenhan (1973)

Question 24

what was the aim of rosenhan’s study?

Answer 24

to investigate whether situational factors affect a diagnosis of sz.

Question 25

what was the method of rosenhans study?

Answer 25

• 8 confederates acted as pseudo patients, going to 12 different hospitals.
• Complained of hearing voices prior to admission, but then stopped pretending to have symptoms once admitted.
• Staff diagnosed 11/12 with schizophrenia and 1 with manic depression.
• Avg hospital stay was 19 days.
• 35 patients detected sanity in pseudo patients; staff misinterpreted normal behaviour as evidence of psychopathology.

Question 26

what were the findings of rosenhans study?

Answer 26

Psychiatric staff cannot always distinguish sanity from insanity.

Any diagnostic method that makes such errors cannot be very reliable or valid.

However, physicians may not identify sanity because it is less risky to diagnose a healthy person as sick than vice versa.

So therefore situational factors do affect diagnosis.

Question 27

what was the conclusion of rosenhans study?

Answer 27

This suggests the validity of psychiatric diagnoses was low and the DSM was flawed.

Question 28

how does predictive validity relate to sz?

Answer 28

In the same way that people diagnosed with schizophrenia rarely share exactly the same symptoms they also have different outcomes.

A diagnosis therefore has little predictive validity. Gender and psycho-social factors do appear to influence outcome.

Question 29

what is meant by co morbidity?

Answer 29

the occurrence of two illnesses together.

Question 30

what did Buckley et al conclude in relation to co morbidity?

Answer 30

Around half of patients with a diagnosis of schizophrenia also have a diagnosis of depression (50%) or substance abuse (47%).

Post-traumatic stress occurred in 29% of cases and OCD in 23%, showing that schizophrenia commonly occurs alongside other mental illnesses and the disorders are co-morbid.

Question 31

how do issues with regards to gender bias undermine diagnostics validity?

Answer 31

Longenecker et al. (2010) reviewed literature and found that since the 1980’s men are more likely to be diagnosed with sz.

Cotton et al (2009) suggest this is because women are better at coping i.e. “more highly functioning” and therefore are diagnosed less than men with similar symptoms.

Research suggests there is a significant variation between countries when it comes to diagnosing schizophrenia.

Question 32

how is there a cultural bias in the diagnosis of sz?

Answer 32

• Copeland et al. (1971) gave a description of an American patient to 134 US and 194 British psychiatrists. 69% of the US psychiatrists diagnosed schizophrenia but only 2% of the British gave the diagnosis of schizophrenia.
• This calls into question the reliability of the diagnosis of schizophrenia as it suggests that patients can display the same symptoms but receive different diagnoses in different cultures.
• This means patient’s culture makes it more/less likely that they will be diagnosed.