schizophrenia

disorder characterised by distorted thinking, impaired emotional responses, poor interpersonal skills and a distortion of reality

An additional experience beyond those of ordinary existence.

Hallucinations
Unusual sensory experiences that have no basis in reality, they can affect any sense

Delusions
Irrational/false beliefs that have no basis in reality, they can make people with schizophrenia behave in ways that make sense to them but may be bizarre to others.

A loss of usual abilities and experiences.
Avolition
Severe loss of motivation to carry out everyday tasks and difficulty to begin or keep up with goal-directed activity.
3 signs: poor hygiene and grooming, lack of persistence in work and education and lack of energy.

Speech poverty
A reduction in the amount and quality of speech

Reliability refers to consistency. This refers to whether we can gain consistent results when classifying and diagnosing Sz. Therefore, the extent to which different classification systems agree upon how schizophrenia should be classified and the extent to which two or more health professionals would agree on the same diagnosis, regardless of time period or culture, measured by inter-rater reliability.
Validity refers to accuracy, the extent to which we are measuring what we intend to measure (schizophrenia). Eg, are the classification systems accurately outlining the signs and symptoms of schizophrenia and are health professionals’ accurately diagnosing schizophrenia?

Cheniaux asked two psychiatrists to diagnose the same 100 patients using the DSM and ICD. One psychiatrist diagnosed 26 according to DSM and 44 according to ICD. The other diagnosed 13 according to DSM and 24 according to ICD. This shows poor inter-rater reliability as one psychiatrist diagnosed almost double the amount than the other psychiatrist. Moreover, it demonstrates poor reliability in the classification of schizophrenia as both psychiatrists diagnosed almost double the amount of patients using the ICD than the DSM, which also calls in to question the validity of the diagnosis.

P - One problem of reliability and validity is that there is often ‘symptom overlap’.
E - This is where two or more conditions share similar symptoms. For example, both schizophrenia and depression involve negative symptoms such as avolition.
E - This questions the validity and reliability of the classification and diagnosis of schizophrenia
E - Because a doctor/psychiatrist may diagnose schizophrenia incorrectly which results in a patient being misdiagnosed.

L - Therefore, individuals will be treated for the wrong condition and their condition will not improve.

P - A further problem with the reliability and validity of the diagnosis and classification of schizophrenia is ‘Co-morbidity’.
E - This is where two illnesses/conditions occur at the same time. For example, Schizophrenia is commonly diagnosed with other conditions. Buckley et al (2009) concluded that 50% of patients diagnosed with schizophrenia also have a diagnosis of depression and 23% have a diagnosis of OCD.
E - This questions the validity and reliability of classification and diagnosis of schizophrenia,
E - because if depression looks a lot like schizophrenia and vice versa they may be better seen as a single condition and doctors may diagnose the wrong condition,

L – Therefore, the wrong treatment may be given to a patient and their condition will not improve.

P - Moreover, another issue with the validity of the diagnosis and classification of schizophrenia is gender bias in diagnosis.
E - Since the 1980s men have been diagnosed with schizophrenia more often than women. This may be because men are more genetically vulnerable to developing schizophrenia than women.
E - However, it could be because females with schizophrenia typically function better than men, being more likely to work and have good family relationships therefore their symptoms may be masked by good interpersonal skills (Cotton et al).
This questions the validity and reliability of the classification and diagnosis of schizophrenia as women who share similar symptoms as men may not receive the same diagnosis as their symptoms seem mild

P - A final problem with the classification and diagnosis of schizophrenia is cultural bias.
E - English people of African origin are much more likely to be diagnosed with schizophrenia in the UK (rates in the West Indies and Africa are not high so this cannot be due to genetic vulnerability).
E - Higher diagnosis rates in the UK may be because some behaviours classed as positive symptoms of schizophrenia are normal in African cultures (e.g. hearing voices as part of ancestor communication).
This is an issue with the validity of classification and diagnosis because it suggests that some individuals from some cultural backgrounds are more likely to be diagnosed than others