Introduction To Sz Flashcards
What is Sz
-severe mental disorder where contact w reality + insight are impaired , an eg of psychosis
-exp by about 1% of worlds popn
-symptoms can interfere severely w everyday tasks so many ppl end up homeless/hospitalised
What is the classification of mental disorder
-process of organising symptoms into categories based on which symptoms frequently cluster together
What is diagnosis and classification in terms of Sz
-diagnosis/classification are interlinked
-to diagnose specifically, need to distinguish one disorder from another
-done by identifying clusters of symptoms that occur together + classifying this is as 1 disorder
-diagnosis is possible by identifying symptoms + deciding what disorder person has
What are 2 major systems for the classification of mental disorder
-World Health Organisations International Classification of Disease (ICD-10) and American Psychiatric Associations Diagnostic and Statistical Manual (DSM-5)
-they differ slightly in their classification of Sz
-eg DSM-5 one +ve symptoms must be present fo diagnosis but 2/more -ve symptoms are sufficient under the ICD
-previous editions of ICD and DSM recognised subtypes of Sz (paranoid Sz involved powerful hallucinations/delusions)
-both have dropped subtypes as were inconsistent
Eg smo with paranoid Sz wouldn’t necessarily show same symptoms few years later
Explain what positive symptoms are of Sz
-additional experiences beyond normal experiences
Explain 2 positive symptoms of Sz
Hallucinations
-unusual sensory experiences w no basis in reality
-some related to events in environment whereas others bear no relationship to what the senses are picking up from the environment eg voices heard either talking to or commenting on a person, often critical
-exp in relation to any sense for eg person may see distorted facial expressions or see animals/people that aren’t there
Delusions
-irrational beliefs/paranoia
-common delusions involve being important historical/religious figure like Jesus or Napoleon
-involve being persecuted by government or aliens
-another type of delusions concern the body + believe under external control
-can make person behave in ways that make sense to them but bizarre to others , a victim of conspiracy
Explain what negative symptoms are
-loss of usual abilities/experiences
Explain 2 negative symptoms of Sz
Speech poverty
-emphasis is on reduction in amount/quality of speech
-sometimes accompanied by delay in persons verbal responses during conversation
-nowadays more emphasis placed on speech disorganisation in which speech becomes incoherent or speaker changes topic mid sentence
-this is classified in DSM-5 as +ve symptom , whilst speech poverty remains a -ve symptom
Avolition
-described as finding it difficult to begin or keep up with goal-directed activity
-often sharp reduction in motivation to carry out activities
-Andreasen identified 3 signs of avoilition: poor hygiene / grooming, lack of persistence in work / education and lack of energy
What is meant by reliability
-consistency
-would the same person get the same diagnosis from different doctors?
-inter-rater : different clinicians, same diagnosis
-test-retest : same diagnosis, same individual, 2 occasions
What is meant by validity
-are we assessing what we set out to assess?
-criterion validity -> evaluates how accurately a test measures outcome it was designed to measure
What is meant by comorbidity
-when 2 or more conditions occur together
-Sz commonly diagnosed w other conditions like personality disorder
-where 2 conditions are frequently diagnosed together, calls into q the validity of classifying 2 disorders separately
What is meant by symptom overlap
-when 2 or more conditions share symptoms
-where conditions share symptoms this calls into q row validity of classifying 2 disorders separately
Whats a strength of diagnosis of Sz and its reliability
psychiatric diagnosis said to be reliable when different diagnosing clinicians reach same diagnosis for same individual (inter rater) and when same clinicians reach same diagnosis for same individual on 2 occasions (test retest)
Prior to DSM-5 , Sz reliability diagnosis was low but has now improved
Osorio et al report excellent reliability for Sz diagnosis in 180 people w dsm-5
Pairs of interviewers achieved inter-rater reliability of +9.7 and test-retest of +9.2
Means we can be reasonably sure that diagnosis of Sz consistently applied
Whats a limitation of the diagnosis of Sz and its validity
One way to assess validity is criterion validity
Cheniaux et al had 2 psychiatrists independently assess same 100 clients using ICD-10 and DSM-5 criteria, found 68 were diagnosed with Sz under ICD, 39 under DSM
Suggests Sz is either over/under diagnosed according to diagnostic system
Suggests either way criterion validity is low
Whats the counterpoint to diagnosis of Sz having low validity
In osorio study , reported excellent agreement between clinicians when used 2 measures to diagnose Sz both derived from DSM system
Means criterion validity for diagnosis of Sz is actually good providing it takes place within a single diagnostic system
Whats another limitation of the Sz diagnosis and its co morbidity w other conditions
Conditions occurring together a lot of the time does question the validity of their diagnosis/classification as might actually be a single condition
Sz consistently diagnosed with other
Eg 1 review found about half those diagnosed w Sz also had diagnosis of depression / substance abuse
Problem for classification as means Sz may not exist distinctly as a condition and is a problem for diagnosis as at least some ppl diagnosed Sz may have unusual cases of conditions like depression
Whats another limitation of Sz diagnosis and the existence of gender bias in diagnosis
Since 80s, men have been diagnosed with Sz more commonly than women 1.4:1
Possible explanation for this is that women less vulnerable than men, maybe due to genetic factors
But seem more likely that women are under diagnosed as have closer relationships , thus get support
Leads to women w Sz often functioning better than men
Under diagnosis is a gender bias, means women may not receive treatment and services that could benefit them
Whats a further limitation of Sz diagnosis and existence of culture bias in diagnosis
Some symptoms of Sz like hearing voices have different meanings in different cultures
Eg in Haiti some people believe hearing voices are communications from ancestors
British people of African - Caribbean origin are up to 9x as likely to receive diagnosis as white British people , altho people living in African - Caribbean countries aren’t ruling out a genetic vulnerability
Most likely explanation for this is culture Bias in diagnosis of clients by psychiatrists from diff cultural backgrounds
Appears to lead to over interpretation of symptoms in black British people
Means british African-Caribbean people may be discriminated against by culturally-biased diagnostic system
Whats a final limiaition of Sz diagnosis and its symptom overlap with other conditions
Considerable overlap between Sz symptoms and symptoms of other conditions
Eg both Sz and bipolar disorder involve +ve symptoms like delusions and -ve symptoms like avolition
In terms of classification this suggests Sz + bipolar may not be 2 different conditions but variations of a single condition
In terms of diagnosis means Sz is hard to distinguish from bipolar
As with co-morbidity , symptom overlap means Sz may not exist a distinct condition and even if it does its hard to diagnose
So both classification/diagnosis are flawed
