Schizophrenia – Revision Notes:
Classification:
1% suffer from disorder, appearing in late adolescence/early 20s with a later
onset in females.
- DSM Criteria A: Delusions, hallucinations, disorganised speech, grossly
disorganised/catatonic behaviour, negative symptoms.
- DSM Criteria B: Social/occupational dysfunction at work, in interpersonal
relations or self care.
- DSM Criteria C: Duration – disturbance of 6 months + 1 month of criteria A.
Positive symptoms: Pathological excesses, including delusions, disorganised
thoughts/speech and hallucinations.
Negative symptoms: Pathological deficits, including apathy, social withdrawal
etc.
Delusions: False beliefs. Persecution; others want to harm you. Grandeur; you
feel very important/powerful. Being controlled; someone controlling your
thoughts/behaviour. Guilt; you feel you have done something bad. Reference;
attach personal meaning to actions of others or events.
Hallucinations: Disruption of perception/sensation. Auditory ; threatening,
commanding, criticising voices. Somatic; about the body, e.g. bugs eating your
insides. Tactile; feelings of tingling/burning. Visual; seeing the devil/someone evil
etc.
Disorganised Speech: Illogical speech which is difficult to follow and jumps
topics without coherence.
Disorganised/Catatonic Behaviour: Bizarre and unpredictable behaviour.
Disorganised behaviour; problems with basic daily life routines such as washing.
Catatonic stupor; remaining motionless for long periods. Catatonic rigidity; rigid
upright posture. Catatonic posturing; awkward positions for long periods.
Catatonic excitement; moving excitedly.
Negative Symptoms: Diminished emotional activity – blunted/flat affect, no
emotion is shown. Avolition; total apathy, lack of interest in goals etc. Poverty of
speech; reduction in amount/quality of speech. Social withdrawal.
Prodomal phase: Work/leisure activities present with mild positive symptoms.
Active phase: Strong positive symptoms lasting months. Residual phase:
Obvious/active symptoms subside, negative symptoms persist, unable to
function socially and at work.
- 1/3 – single/few brief episodes. 1/3 – episodic pattern throughout life. 1/3 – no
periods of remission, acute to chronic symptoms.
, Validity and Reliability:
Validity:
The accuracy of the diagnosis; should represent a real disorder and accurately
reflect symptoms. Predictive validity; predict how disorder develops and develop
effective treatment.
Rosenhan (1973): 8 mentally healthy people,12 mental hospitals, voices say
‘thud, empty, hollow’. Admitted to 11/12 hospitals with schizophrenia, stayed 7-
52 days (average 19). Validity of diagnosis poor, inaccurately labelled normal
behaviour (e.g. lining up at canteen) as symptoms. Doctors could not distinguish
sane from insane. Lacks temporal validity, new modern psychiatry.
- Highlights issues with validity of diagnosis. Lacked predictive validity. Different
diagnostic material – Cheniawk et al diagnosed more with ICD > DSM; over-
diagnosing/under-diagnosing. Symptom overlap – bipolar, autism, cocaine and
dissociative identity disorder. Flanagan et al ICD = schizophrenia, DSM =
bipolar. Co-morbidity; the rate at which other disorders occur alongside
schizophrenia – Buckley depression (50%), substance abuse (47%), PTSD (29%)
OCD (23%).
Reliability:
The consistency of diagnosis. Inter-rater reliability; consistency between
clinicians. Test-retest reliability; consistency across patients displaying same
symptoms. Cheniaux et al – 2 psychiatrists independently diagnose 100
patients (DSM and ICD), 26 DSM and 44 ICD vs 13 DSM and 24 ICD, inter-relater
reliability low. Beck et al 54% concordance between practitioners’ diagnoses
when assessing 153 patients. Soderberg et al DSM concordance = 81%.
Cultural Bias in Diagnosis:
Variations in the rate of diagnosis of schizophrenia across people from different
cultural backgrounds. Cochrane Afro-Caribbean origin 7x more likely to be
diagnosed. McGovern & Cope 2/3 detained in Birmingham hospitals were Afro-
Caribbean, 1/3 white/Asian. Escobar – majority of UK psychiatrists are white,
may misinterpret behaviour. Different social norms – African culture acceptable
to hear voices; communicate with ancestors. Fernando – ethnic minorities
experience greater levels of racism and poverty, stress could trigger
schizophrenia. Cochrane Afro-Caribbeans have lower immunity to flu; children
born to mothers who have flu while pregnant = 88% increased risk of
schizophrenia.
Gender Bias in Diagnosis:
Variations in the rate of diagnosis of schizophrenia for males and females.
Longenecker et al – since 80s, men diagnosed > women, later diagnosis in
females. Cotton et al – females under-diagnosed as they tend to function
better, mask symptoms well/appear too mild. Loring & Powell 290 psychiatrists
read vignettes of behaviour. 56% males vs 20% females diagnosed; female
psychiatrists showed less gender bias due to stereotypical views.
Classification:
1% suffer from disorder, appearing in late adolescence/early 20s with a later
onset in females.
- DSM Criteria A: Delusions, hallucinations, disorganised speech, grossly
disorganised/catatonic behaviour, negative symptoms.
- DSM Criteria B: Social/occupational dysfunction at work, in interpersonal
relations or self care.
- DSM Criteria C: Duration – disturbance of 6 months + 1 month of criteria A.
Positive symptoms: Pathological excesses, including delusions, disorganised
thoughts/speech and hallucinations.
Negative symptoms: Pathological deficits, including apathy, social withdrawal
etc.
Delusions: False beliefs. Persecution; others want to harm you. Grandeur; you
feel very important/powerful. Being controlled; someone controlling your
thoughts/behaviour. Guilt; you feel you have done something bad. Reference;
attach personal meaning to actions of others or events.
Hallucinations: Disruption of perception/sensation. Auditory ; threatening,
commanding, criticising voices. Somatic; about the body, e.g. bugs eating your
insides. Tactile; feelings of tingling/burning. Visual; seeing the devil/someone evil
etc.
Disorganised Speech: Illogical speech which is difficult to follow and jumps
topics without coherence.
Disorganised/Catatonic Behaviour: Bizarre and unpredictable behaviour.
Disorganised behaviour; problems with basic daily life routines such as washing.
Catatonic stupor; remaining motionless for long periods. Catatonic rigidity; rigid
upright posture. Catatonic posturing; awkward positions for long periods.
Catatonic excitement; moving excitedly.
Negative Symptoms: Diminished emotional activity – blunted/flat affect, no
emotion is shown. Avolition; total apathy, lack of interest in goals etc. Poverty of
speech; reduction in amount/quality of speech. Social withdrawal.
Prodomal phase: Work/leisure activities present with mild positive symptoms.
Active phase: Strong positive symptoms lasting months. Residual phase:
Obvious/active symptoms subside, negative symptoms persist, unable to
function socially and at work.
- 1/3 – single/few brief episodes. 1/3 – episodic pattern throughout life. 1/3 – no
periods of remission, acute to chronic symptoms.
, Validity and Reliability:
Validity:
The accuracy of the diagnosis; should represent a real disorder and accurately
reflect symptoms. Predictive validity; predict how disorder develops and develop
effective treatment.
Rosenhan (1973): 8 mentally healthy people,12 mental hospitals, voices say
‘thud, empty, hollow’. Admitted to 11/12 hospitals with schizophrenia, stayed 7-
52 days (average 19). Validity of diagnosis poor, inaccurately labelled normal
behaviour (e.g. lining up at canteen) as symptoms. Doctors could not distinguish
sane from insane. Lacks temporal validity, new modern psychiatry.
- Highlights issues with validity of diagnosis. Lacked predictive validity. Different
diagnostic material – Cheniawk et al diagnosed more with ICD > DSM; over-
diagnosing/under-diagnosing. Symptom overlap – bipolar, autism, cocaine and
dissociative identity disorder. Flanagan et al ICD = schizophrenia, DSM =
bipolar. Co-morbidity; the rate at which other disorders occur alongside
schizophrenia – Buckley depression (50%), substance abuse (47%), PTSD (29%)
OCD (23%).
Reliability:
The consistency of diagnosis. Inter-rater reliability; consistency between
clinicians. Test-retest reliability; consistency across patients displaying same
symptoms. Cheniaux et al – 2 psychiatrists independently diagnose 100
patients (DSM and ICD), 26 DSM and 44 ICD vs 13 DSM and 24 ICD, inter-relater
reliability low. Beck et al 54% concordance between practitioners’ diagnoses
when assessing 153 patients. Soderberg et al DSM concordance = 81%.
Cultural Bias in Diagnosis:
Variations in the rate of diagnosis of schizophrenia across people from different
cultural backgrounds. Cochrane Afro-Caribbean origin 7x more likely to be
diagnosed. McGovern & Cope 2/3 detained in Birmingham hospitals were Afro-
Caribbean, 1/3 white/Asian. Escobar – majority of UK psychiatrists are white,
may misinterpret behaviour. Different social norms – African culture acceptable
to hear voices; communicate with ancestors. Fernando – ethnic minorities
experience greater levels of racism and poverty, stress could trigger
schizophrenia. Cochrane Afro-Caribbeans have lower immunity to flu; children
born to mothers who have flu while pregnant = 88% increased risk of
schizophrenia.
Gender Bias in Diagnosis:
Variations in the rate of diagnosis of schizophrenia for males and females.
Longenecker et al – since 80s, men diagnosed > women, later diagnosis in
females. Cotton et al – females under-diagnosed as they tend to function
better, mask symptoms well/appear too mild. Loring & Powell 290 psychiatrists
read vignettes of behaviour. 56% males vs 20% females diagnosed; female
psychiatrists showed less gender bias due to stereotypical views.
