Lesson 3: The reliability and validity in the diagnosis and classification of schizophrenia (co-morbidity, culture bias, gender bias and symptom overlap) Flashcards
What is reliability in terms of the ICD-10 and the DSM-V?
- ICD-10 and DSM-V should be reliable (should be good consistency of diagnosis of schizophrenia over period of ⏰ and between different psychologists)
- Inter rater reliability- 2 different psychologists agree and both diagnose illness schizophrenia
- DSM-V ⬆️ reliable than ICD-10- symptoms for schizophrenia in DSM-V outlined for each category and ⬆️ specific
- Reliability for diagnosing schizophrenia ⬆️ superior than other disorders
- DSM-V and ICD-10 updated every few years- means classification and diagnosis of schizophrenia improved in validity and reliability over ⏰
What is validity in terms of schizophrenia?
- Means that diagnostic system (ICD/DSM) assesses what claims to be assessing (schizophrenia)
- If DSM and ICD valid then confidence in saying that people diagnosed with schizophrenia, do actually have disorder ✖️ another
What is content validity in terms of schizophrenia?
Extent to which assessment covers range of symptoms of schizophrenia- e.g. interviews or checklist of schizophrenic symptoms- cover all symptoms ✖️ just a few
What is co-morbidity?
Extent that 2 or ⬆️ illnesses occur simultaneously in patient e.g. schizophrenia and depression- important issue when considering validity in diagnosing and classifying schizophrenia
Are there any problems when diagnosing someone with schizophrenia?
Swets (2014)- stated that 1% of population will suffer from schizophrenia and 2.5% from OCD BUT 12% of schizophrenic patients meet diagnostic criteria to also be suffering from OCD (co-morbid)- causes problem of classifying illness as schizophrenia and not another psychological illness
What other disorders have similar symptoms to schizophrenia?
1) Mood disorders (depression)
2) OCD
What must a psychologist do to ensure they get the right diagnosis?
… psychologist MUST use professional judgement to categorise patient as either depressed (mood disorder) or schizophrenic- … full consultation of DSM and ICD to get the correct and valid diagnosis of the illness
State the evaluation points of co-morbidity when diagnosing schizophrenia
👎- DSM and ICD criticised to be lacking validity- too much overlap between schizophrenia, mood disorders and OCD- may-> clinicians classifying patient as having schizophrenia AND depression (co-morbid) to get round problem of making judgement between schizophrenia and depression- 2nd opinion from another clinician may be required to make accurate and valid diagnosis
👎- Sim (2006)- found that diagnosis of schizophrenia can be invalid and unreliable because of the issues surrounding co-morbidity- found that 32% of 142 hospitalised schizophrenic patients had additional mental disorders (co-morbid)- problem when diagnosing and classifying the illness
👎- Schizophrenic patients used alcohol 🍷, cannabis and cocaine (suffer from substance abuse and drug addiction) before diagnosed with illness- … makes it incredibly difficult to give reliable and valid diagnosis of schizophrenia because some symptoms of illness same as those who use drugs and alcohol (co-morbid)
👎- Jeste (1996)- identified problems with previously conducted research which-> ⬇️ levels of validity- found that schizophrenic patients with co-morbid illnesses often excluded from research BUT majority of schizophrenic patients do actually suffer with other psychological illnesses … research findings from schizophrenia patients ✖️ be generalized to all patients and might be invalid overall
How can culture bias occur in the diagnosis of schizophrenia?
Culture- has influence on diagnosis and classification of schizophrenia
e.g. “hearing 👂 voices” (auditory 👂 hallucination)- influenced by culture:
Luhrmann (2015) interviewed 60 adults with schizophrenia (20 from Ghana 🇬🇭, 20 from 🇮🇳 and 20 from 🇺🇸)- all patients reported hearing 👂 voices BUT patients from 🇺🇸 reported most ➖ experiences associated with voices … culture has influence on reliability of diagnosing schizophrenia
Davison and Neale (1994)- explain that in Asian cultures some people rewarded and praised if ✖️ show suffering from emotional/psychological problem … people from Asian cultures maybe unlikely to seek psychological help if have schizophrenia
BUT in Arabic cultures- people encouraged to show emotions … this culture ⬆️ likely to seek help for schizophrenia- … cultural bias when examining no. of people from different cultures that suffer from schizophrenia
State the evaluation points of culture bias when diagnosing schizophrenia
👎- cultural relativism- psychologist may ✖️ be able to understand patient’s symptoms correctly due to ✖️ fully understanding their cultural background could-> misdiagnosis of schizophrenia- ALSO psychologist could make incorrect judgements about patient in terms of cultural background- ALSO people from African background may be wrongly diagnosed with schizophrenia due to fact that they claim that they can 👂 voice of God (religion)- in African culture- seen as gift BUT in western 🌎- interpreted as auditory 👂 hallucination- judged as symptom of schizophrenia-> incorrect and invalid diagnosis
👍- Research support for cultural relativism- Afro-Caribbean people have little immunity to flu- 👶 born to 🤰 who had flu when pregnant 🤰 in second trimester have 88% ⬆️ chance of developing schizophrenia- … cultural vulnerability means Afro-Caribbean’s at ⬆️ risk of developing schizophrenia than white population
👎- Cochrane (1995) found research evidence- suggests that diagnosing schizophrenia invalid for immigrants (often faced racism and social deprivation- ➖ affected their mental 🧠 health and could possibly-> schizophrenia)- … clinicians might wrongly attribute diagnosis of schizophrenia to ethnicity rather than to stressors occurred in patient’s life
How may gender bias occur in the diagnosis of schizophrenia?
Accuracy of diagnosing schizophrenia ALSO dependent on gender of patient
Male 👨 sufferers of schizophrenia tend to show ⬆️ ➖ symptoms than 👩 AND also suffer ⬆️ from substance 🍷 abuse
Disagreement amongst clinicians when diagnosing schizophrenia- have stereotypical beliefs about gender
Critics of DSM argue that healthy adult 🏃♂ linked ⬆️ to healthy 👨 rather than healthy 👩 … DSM could be viewed as gender biased when trying to classify and diagnose symptoms of schizophrenia
State the evaluation points of gender bias when diagnosing schizophrenia
👎- research support- Loring (1985)- psychologists had to judge patients using diagnostic criteria
When patient described as 👨 or ✖️ info given about gender- 56% of psychologists diagnosed patient as schizophrenic
When patient described as 👩- 20% of psychologists diagnosed schizophrenia
… gender bias when diagnosing schizophrenia- affected by gender of patient AND psychologist-> invalid diagnosis
👍- Research evidence- Kulkarni (2001)- suggests 👩 ⬇️ vulnerable than 👨 to schizophrenia- female sex hormone estradiol helps treat schizophrenia in 👩 … protective factor present in 👩 might ⬇️ chances of getting schizophrenia compared to 👨
👎- validity of diagnosis of schizophrenia questioned- 👩 develop schizophrenia 4-10 years later than 👨 do- ALSO different types of schizophrenia that 👨 and 👩 vulnerable to- taken into account when diagnosing and classifying illness
How may symptom overlap occur in the diagnosis of schizophrenia?
➕ and ➖ symptoms of schizophrenia- valid diagnosis of schizophrenia BUT some symptoms of schizophrenia found in the other disorders e.g. depression (symptom overlap)- affects validity of diagnosis
Other illnesses which show symptom overlap with schizophrenia include:
1) Bipolar depression (depressed mood, episodes of mania/energy, unpredictable, hallucinations delusions)
2) Depression (hallucinations)
3) Cocaine intoxication (paranoia, disorganized speech, delusions)
4) Schizotypal personality disorder (similar symptoms of schizophrenia, but milder)
State the evaluation points of symptom overlap when diagnosing schizophrenia
👎- symptom overlap-> misdiagnosis of schizophrenia
Ketter (2005)- found evidence schizophrenia being misdiagnosed as another illness due to symptom overlap-> years of delays- schizophrenia patients ✖️ receive necessary treatment-> illness getting worse-> ⬆️ rates of suicide and deterioration
👍- conduct 🧠 scan or EEG to validly diagnose schizophrenia- examines 🧠 in detail and checks grey matter in 🧠 (schizophrenic patients tend to suffer from deterioration of grey matter)
ALSO patients with bipolar depression ✖️ have ⬇️ in grey matter … 🧠 scan helps differentiate-> ⬆️ validity
👎- Research evidence supported 💡 that inter rater reliability ⬇️ when asking psychologists to agree on diagnosing schizophrenia and not another illness
Beck (1961)- studied 154 patients with 2 different psychiatrists- found inter rater reliability was 54% (… 54% agreement between 2 psychiatrists in terms of diagnosis of illness schizophrenia)- could be due to symptom overlap
