schizophrenia ao3s

strength of schizophrenia diagnosis

RELIABLE - a diagnosis is reliable when diff diagnosing clinicians reach the same diagnosis for the same individual (inter-rater) and when the same clinician reaches the same diagnosis for the same person on two diff occasions (test-retest). OSARIO et al found excellent reliability in the diagnosis of 180 individuals using DSM-5 where pairs of interviewers achieved inter-rater (+0.97%), test-retest (+0.92%)

L - diagnosis of SZ is likely consistently applied

weakness of the diagnosis of schizophrenia

Cheniaux et al had two psychiatrists assess the same 100 clients using ICM and DSM-5 and found that 68 were diagnosed w SZ (ICD) compared to 39 diagnosed (DSM-5). ICD requires two or more negative systems for diagnosis whereas DSM requires only one positive symptom. An issue could be that the negative symptoms of SZ are less specific to SZ, making it easier to meet the threshold

L - SZ is either over (ICD) or under (DSM) diagnosed according to the diagnostic system - the criterion validity is therefore low.

weakness 2 of diagnosis of schizophrenia

gender bias - men have been diagnosed more frequently than women (1.4 to 1 ratio). women usually have closer relationships and hence get more support which is why they might be under-diagnosed. LORING AND POWELL asked male and female psychiatrists to diagnose patients using the DSM and found that when no gender info was given 56% were diagnosed with SZ, vs. when patients were described as female, 20% were diagnosed

L - lack of consistency reduces inter-rater reliability + reduces the validity of diagnosis through gender bias as women won’t receive the treatment they might benefit from

weakness 3 of diagnosis of schizophrenia

culture bias - hearing voices (positive symptom of SZ) in Afro-Caribbean cultures is seen as communication from ancestors. British ACs are 9x as likely to receive SZ diagnosis than white British. This shows cultural bias in the diagnosis of clients in a diff cultural background to the psychiatrist. White psychiatrists tend to over-interpret symptoms and distrust the honesty of POC during diagnosis (ESCOBAR) and when the given the same description of patients, 69% of US psychiatrists diagnosed SZ vs. 2% of UK psychiatrists (COPELAND)

L - there is a lack of consistency between cultures and the same diagnosis should be given regardless of culture (as it reduces reliability) OR

L - this suggests issues with the validity of diagnosis as individuals from some cultures are more likely to be diagnosed due to bias.

weakness 4 of the diagnosis of schizophrenia

symptom overlap - both SZ and BPD share positive symptoms of delusions as well as negative symptoms such as avolition - this questions the validity of classifying them as two diff disorders as there may be variation of a single condition. in terms of diagnosis it means that SZ is hard to distinguish from BPD

L - this decreases the validity of diagnosis as it could lead to incorrect diagnosis and leads to low reliability as as diagnoses can become inconsistent

weakness 5 of diagnosis of schizophrenia

co-morbidity - if conditions occur together, this questions the validity of the diagnosis and classification as they may be a single condition. SZ is commonly diagnosed with other conditions e.g. BUCKLEY’s review found that 50% of those w/ SZ also had depression, 47% had co-morbidity w/ substance abuse and 23% w/ OCD

L - this decreases the validity of diagnosis as it could lead to incorrect diagnosis (unusual case of depression rather than SZ) which could lead to incorrect treatments, impacting recovery, employment and family life etc.

strength of the psychological SZ explanation

evidence linking FD to SZ - READ ET AL found that adults w/ SZ = type C or D attachment (disinhibited). 69% of women + 59% men suffered physical/sexual abuse history b4 SZ diagnosis. Mørkved et al found that most adults w/ SZ reported at least one childhood trauma event, most often abuse

L - strongly suggests that FD makes ppl more vulnerable to SZ

weakness of the psychological SZ explanation

weak evidence to support FD - little to no evidence on importance of schizophrenogenic mother or double-bind theory. both theories are based on outdated concepts (e.g. assessing personality of mothers for contributing to child’s disorders). socially sensitive research leads to parent blaming as well

L - undermine the appropriateness and credibility of the family-based explanation

strength of the the psychological SZ explanation 2

strong evidence for cognitive explanation (dysfunctional info processing) - STIRLING ET AL compared 30 SZ ppl to control group on diff cognitive tasks including stroop test and found ppl w/ SZ took twice as long on stroop test vs. control

L - shows poorer cognition, supporting concept of central control as they were unable to suppress non-essential processes such as urge to read words aloud rather than colour.

weakness 2 of the psychological SZ explanation

cognitive only explains proximal rather than distal explanations - cog explanation = descriptive not explanatory. focus is placed on present symptoms (proximal) rather than distal causes (genetic/FD) which causes cause-and-effect issues. unclear if cog dysfunction drives neurological changes or results from them

L - cog theories are partial explanations, describing how symptoms occur but not why SZ develops