Classification and Diagnosis (Schizophrenia) Flashcards
Schizophrenia
• is not a split personality as many think
• Greek etymology: ‘schizo’ meaning split
and ‘phrena’ meaning mind
• the split in schizophrenia occurs between a person’s though processes and reality
Schizophrenia Statistics
• 1% of the world are diagnosed
• prevalence rates of between .33 and 15%
• most common mental disorder, accounting for 50% of all mental health in unit services
• between 24 and 55 million people have schizophrenia
Psychosis
• refers to severe mental problems where the individual loses contact with reality
• unlike neurosis where the individual is aware that they have problems
• about 25% of sufferers will “get better” after only one episode of the illness; 50-65% will improve but continue to have bouts of the illness
• the remainder will have persistent difficulties (Stirling and Hellewell, 1999)
Classification of Schizophrenia
• ICD-10: International Classification of the Causes of Disease and Death (World Health Organisation)- recognises a range of subtypes
• DSM-V: Diagnostic and Statistical Manual of Mental Disorder (American Psychiatric Association)- used to also recognise the subtypes but the most recent DSM-V have dropped these
• ICD-11 is the same as DSM-V in that it does not refer to subtypes
(ICD-10 diagnoses) Disorganised Schizophrenia
• the person’s behaviour is generally disorganised and no goal directed
• symptoms include thought disturbances (including delusions and hallucinations), an absence of expressed emotion, incoherent speech, large mood swings and a loss of interest in life (social withdrawal)
• it is usually diagnosed in adolescence or young adulthood
(ICD-10 Diagnoses) Catatonic Schizophrenia
- is diagnosed if the patient has severe motor abnormalities such as unusual gestures or use of body language
- sometimes patients gesture repeatedly, using complex sequences of finger, hand and arm movements, which appear to have some meaning for them
- this type often involves doing opposite to what is being asked or repeating everything that is said
- the main feature is almost total immobility for hours at a time, with the patient simply staring blankly
-Echolalia: the involuntary parrot like repitition (echoing) of a word or phrase just spoken by another person
-Echopraxia: the involuntary imitation or repetition of the body movements of another person, sometimes practiced by catatonic patients
(ICD-10 Diagnoses) Paranoid Schizophrenia
• this type involves delusions of various kinds (persecution and grandeur); however, the patient remains emotionally responsive
• they are more alert than patient with other types of schizophrenia
• people who are diagnosed with Paranoid schizophrenia tend to be argumentative
(ICD-10 Diagnoses) Residual Schizophrenia
• this is the category that describes people who, although they have had an episode of schizophrenia during the past 6 months and still exhibit some symptoms, these are not strong enough to merit putting them in the other categories.
• This type consists of patients who are experiencing mild symptoms
(ICD-10 Diagnoses) Undifferentiated Schizophrenia
• this is a broad, ‘catch-all’ category which includes patients who do not clearly belong within any other category
• they show symptoms of schizophrenia but do not fit into the other types
Positive Symptoms of Schizophrenia
• hallucinations
• delusions
• disorganised speech
• grossly disorganised or catatonic behaviour
Negative Symptoms of Schizophrenia
• avolition
• speech poverty
• affective flattening
• anhedonia
-these are less dramatic but tend to last longer than positive symptoms
Secondary Symptoms of Schizophrenia
• depression
• loss of employment
• breakdown of relationships
these are the results of the difficulties of living with the disorder
Symptoms and Diagnosis of Schizophrenia General
• the symptoms of schizophrenia are typically divided into positive and negative
• some symptoms are rare in normal, everyday experiences; these are known as positive symptoms
• positive symptoms appear to reflect an excess or distortion of normal function (i.e. delusions and hallucinations)
• other symptoms are much less dramatic and can be experienced in everyday life (i.e. loss of energy, reduced personal hygiene); these are known as negative symptoms
• while the negative symptoms are less dramatic, they tend to last for longer than the positive symptoms
• a person may also be affected by secondary impairments such as depression, as a result of the difficulties of living with the disorder (Davison and Neale) 2001
(DSM-V criteria) Criterion A
• two or more of the following symptoms
- delusions
- hallucinations
- disorganised speech (e.g. frequent derailment or incoherence)
-grossly disorganised or catatonic behaviour
-negative symptoms (affective flattening, alogia of avolition)
• however, only one criterion A symptom is required if delusions are bizarre or hallucinations consist of a voice keeping up a running commentary on the person’s behaviour or thoughts, or two or more voices conversing with each other
(DSM-V criteria) Criterion B
• social/occupational dysfunction
• for a significant portion of the time since onset, one or more major areas of functioning such as work, interpersonal relations or self0care are markedly below the level achieved prior to onset
(DSM-V criteria) Criterion C
• duration
• continuous signs of disturbance persist for at least 6 months
• this 6 month period must include at least 1 month of symptoms (or less if successfully treated) that meet criterion A
• during non-active periods, disturbance may be limited to negative symptoms or two or more symptoms in criterion A in attenuated form (e.g. odd beliefs, unusual perceptual experiences)
Mental Health Act (1983)
• someone with schizophrenia may not realise they are ill and can refuse treatment when they need it
• as a result, they can be admitted to hospital against their will and given treatment without their consent under the Mental health Act. This should only happen if their health is at risk, if they are a danger to themselves, or if they may be a danger to others
Validity (from Rosenhan)
• the diagnosis of schizophrenia lacks validity, as psychiatrists cannot distinguish between real and pseudo-patients
• being diagnosed with schizophrenia is a ‘sticky label’- it is difficult to remove and with serious consequences- and yet it is manufactured by psychiatrists with low degrees of accuracy
Co-morbidity
affects reliability and validity
• co-morbidity is the occurrence of two illnesses or conditions occurring simultaneously
• this can create a problem with reliability of diagnosis as there may be confusion over which disorder is being diagnosed, e.g. with schizophrenia and depression
• patients with schizophrenia also have a diagnosis of depression (50%), substance abuse (47%), PTSD (29%) and OCD (23%) Buckley et al. (2009)
• Co-morbidity raises issues of descriptive validity, as having simultaneous disorders suggests that schizophrenia may not actually be a separate disorder
Symptom overlap
• there is a considerable overlap of symptoms of schizophrenia and other conditions
• both schizophrenia and bipolar disorder for example involve positive symptoms like delusions and negative symptoms like avolition
• this calls into question the validity and the classification and the diagnosis of schizophrenia
• under ICD a patient might receive a diagnosis of schizophrenia, however many of the same patients would receive a diagnosis of bipolar disorder under DSM criteria
Reliability negative
consistency of diagnosis
• an important measure of reliability is inter-rater reliability
• in relation to diagnosis, this means that different clinicians make identical, independent diagnosis of the same patient
• Cheniaux et al. (2009) has two psychiatrists independently diagnose 100 patients using both DSM and ICD criteria
P1: diagnosed 26 by DSM, 44 ICD
P2: 13 DSM, 24 ICD
• shows weakness of diagnostic criteria for schizophrenia
Reliability (positive)
• even if reliability of diagnosis based on classification systems is not perfect, they do provide practitioners with a common language, permitting communication of research ideas and findings which may ultimately lead to a better understanding of the disorder and the development of better treatments
• evidence does generally suggest that reliability of diagnoses has improved as classifications system have been update
Sex bias in diagnosis
• Longenecker et al. (2010)- since 1980, males have been diagnosed with schizophrenia more often than females
• men are more genetically vulnerable to developing the disorder
• Sex bias: Loring and Powell (1988)- 290 psychiatrists were asked to diagnose two patients with the same symptoms
• Cotton et al. (2009)- female patients typically function better than male patients (better interpersonal functioning)
• suggests the validity of the criteria are poor: if females are under-diagnosed, it shows that the procedures for diagnosis only work well on patients of one sex
Cultural Bias in diagnosis
• The tendency to over-diagnose members of other cultures as suffering from schizophrenia
• African Americans and English people of Afro-Caribbean origin are several times more likely than white people to be diagnosed with schizophrenia
• this suggests that the validity of the diagnosis is poor because either it is confounded by cultural beliefs and behaviours in patients or by a racist distrust of black patients on the part of mental health practitioners (Escobar, 2012)
Whaley (2004)and Copeland et al. (1971)
• Whaley (2004) believes the main reason for the incidence of schizophrenia among black Americans (2.1%) being greater than among white Americans (1.4%) is cultural bias, where ethnic differences in symptom expression are overlooked or misinterpreted by practitioners
• Copeland et al. (1971)- 69% of American psychiatrists diagnosed a patient as having schizophrenia compared with 2% of British psychiatrists
Validity- accuracy of diagnosis
• an important measure of validity is criterion (concrete) validity: do different assessment systems arrive at the same diagnosis for the same patient?
• Cheniaus et al. (2009) stud suggests that it is much more likely to be diagnosed using ICD rather than DSM
• this suggests that schizophrenia is either over-diagnosed in ICD or under-diagnosed in DSM
