Schizophrenia - Paper 3

What is Schizophrenia?

Psychotic disorder - individual has severe mental health issues that causes them to lose touch with reality.

Can not distinguish their own thoughts and ideas from reality.

First identified by Kraeplin (1886) - Dementia Praecox.

Bleuler (1911) - Schizophrenia.

Schizo = split.

Phrenia = mind.

Better understood as a split between cognition and emotion.

Prevalence of Schizophrenia

How common in the population.

Affects around 1% of population. 

1 in every 100.

Equally common in males and females.

Males - diagnosed in late teens to mid 20’s.

Females - diagnosed in early 30’s.

Prognosis of Schizophrenia

Expected outcome of mental health in terms of recovery.

Bleuler (1978) - longitudinal study of 2000 schizophrenics.

Found:

• Symptoms most severe in early adulthood (first 5 years after onset).

• 40% recover from positive symptoms.

• 20% full recover if diagnosed early.

• 40% continue to suffer symptoms for the rest of their lives.

Symptoms of Schizophrenia 

• hallucinations – hearing or seeing things that do not exist outside of the mind. They are faulty sensory input.

• delusions – unusual beliefs not based on reality

• muddled thoughts and speech based on hallucinations or delusions

• losing interest in everyday activities

• not wanting to look after yourself and your needs, such as not caring about your personal hygiene

• wanting to avoid people, including friends

• feeling disconnected from your feelings or emotions

Positive symptoms

Delusions.

Hallucinations.

Disorganised speech.

Negative symptoms

Flattened affect.

Reduced speech.

Lack of initiative.

What is classification?

Identifying groups or patterns of behavioural, emotional, physical or motivational symptoms that happens to form a mental disorder.

Syndrome - groups of symptoms happen together.

Important:

• helps in treatment.

• helps identify cause of their disorder.

• helps with prognosis - predicting the future course of disorder.

Diagnostic criteria

Set of signs, symptoms, and tests developed for use in routine clinical care to guide the care of individual patients.

The diagnosis typically guides treatment. 

Classification criteria

Standardised definitions grouping health issues into categories based on similar properties.

These categories may be grouped by type of disease, body system or anatomy.

Classification criteria have no treatment implications for patients

What is the DSM classification system?

First published in 1952.

Used by American Psychiatric Association.

Has had a number of revisions.

Current edition - DSM-5-TR published in 2022.

Has over 300 mental disorders arranged in several categories.

Each disorder - lists specific diagnostic criteria that must be met for diagnosis to be given.

Includes details on symptoms that have to be present and for how long (inclusion criteria) and details on symptoms that must not be met (exclusion criteria).

Reliability of diagnosis

Consistency of diagnosis.

2 or more practitioners make the same diagnosis of SZ of the same person.

Inter-rater reliability = clinicians make identical diagnosis of the same patient.

But does not always happen as shown:

Beck et al 1963 - reviewed 153 patients who had been diagnosed by multiple doctors found only 54% concordance rate between the doctors assessments, suggests there is low inter-rater reliability in the diagnosis of SZ. 

Could mean many people have been diagnosed incorrectly , potentially having inappropriate treatment.

Test re-test reliability (external reliability) - making the same diagnosis of the patient on separate occasions based on the same information.

Weakness of reliability of SZ diagnosis

Research study - Copeland (1970).

Shows how the culture of the clinician can damage inter-rater reliability.

Found - with the same description of a patient was given to British psychiatrists and US Psychiatrists 69% of US psychiatrists diagnosed the patient with SCH compared to just 2% of British Psychiatrists.

US clinicians are more likely to diagnose SCH than their UK counterparts.

Questions the reliability of the diagnosis of schizophrenia.

Patients may display the same symptoms but have different diagnoses due to the clinicians ethnic background

(With standard criteria) Inter- rater reliability cannot be guaranteed.

Potential influence of cultural bias.

Weakness of reliability of SZ diagnosis

Research study - Read (2004).

Test re-test analysis is as low as 37%.

Considering possible false positives and false negatives this could create. 

Patients without - diagnosed as having SZ.

Patients with - diagnosed as not having SZ.

People who need treatment may not get it or get the wrong treatment.

Strength of reliability of SZ diagnosis

Tool used in diagnosis. 

Farmer (1988) - standardised interview techniques known as Present state examination (PSE) focuses on frequency and severity of symptoms.

Increases reliability of diagnosing SZ.

Mental status test assessing a patient's current psychiatric condition.

Contains 140 items each scored on a 3-point or 4-point scale.

Can be learned by American-trained clinicians with inter-rater reliability comparable to that of British and European clinicians.

Using the right standardised tools - leads to reassurance for patients that the outcome and treatments they receive are based on diagnosis that would be consistent amongst practitioners.

Strength of reliability of SZ diagnosis

DSM improved the reliability.

DSM V - stripped the criteria out that was difficult to differentiate.

For example, deciding between bizarre (an impossible) delusion and non-bizarre (possible) delusions.

Mojtabi & Nicholson (1995) - 50 psychiatrists failed to differentiate between bizarre and non bizarre delusions.

May receive the wrong diagnosis.

Bizarre - belief of FBI putting a microchip inside you to track you.

Non-bizarre - belief of being followed by FBI.

Has helped to increase the reliability of diagnosis.

Adapts and changes certain specific criteria to make categorising more consistent.

Validity of SZ diagnosis

Accuracy of diagnosis.

Co-morbidity - when one or more disorders exists alongside a primary diagnosis, two different conditions co-exist in the same patient at the same time, questions validity of their classification (many people have multiple problems rather single problems), SZ with substance abuse or OCD.

Mental health = complex area not a simple one, challenges validity of diagnosis.

Overlapping symptoms - SZ shares symptoms with other conditions, leads to invalid diagnosis.

Symptoms of SZ = not pathognomic.

Bipolar disorder, OCD  and autism = overlapping symptoms.

Read et al (2011) - estimated 13 % of population hear voices but only 1% are diagnosed with SZ.

SZ and bipolar disorder = positive symptoms like delusions and negative symptoms like avolition.

This might lead to problems with diagnosis/classification as shared symptoms could lead to an incorrect diagnosis, show a symptom typical of SZ but could instead have another condition.

Weakness of validity of SZ diagnosis

Research evidence.

Rosenhan (1973) - investigated the reliability and validity of staff diagnosis in psychiatric hospitals, pseudo-patients with no mental illness pose as mentally ill to see if staff in hospitals could accurately diagnose them, 8 ‘sane’ people complain of hearing unclear voices saying ‘thud, hollow, empty’, all admitted to hospital and all but one was diagnosed with SZ, the other with manic-depressive psychosis.

Upon admission, all pseudo-patients stopped showing any ‘symptoms’ and took part in ward activities.

Average length of stay was 19 days.

Release = pseudo-patients were given the diagnosis of SZ  ‘in remission’.

2nd follow up study = one hospital was told that one or more pseudo-patients would try to be admitted, hospital staff were asked to rate the patients on the likelihood of them being a pseudo-patient.

44% were judged by at least one member of staff to be a pseudo patient.

No pseudo patients were ever sent.

Real patients with mental illness symptoms were turned away.

Psychiatrists could not reliably tell the difference between an insane or sane person.

Questions the reliability of a SZ diagnosis.

Normal behaviour was assumed as abnormal.  

Psychiatric diagnoses using the DSM-2 at the time was flawed.

Weakness of validity of SZ diagnosis

Research evidence - comorbidity reduces the validity of diagnosis.

Buckley et al (2009) - 50% of patients with a diagnosis of schizophrenia also have a diagnosis of depression (50%) or substance abuse (47%), post-traumatic stress occurred in 29% of cases and OCD in 23%.

Shows that schizophrenia commonly occurs alongside other mental illnesses and the disorders are co-morbid.

Hard to judge which part of the disorder is just SZ and which belongs to another disorder.

Meaning the wrong focus of treatment may be provided to the patient.

Weakness of validity of SZ diagnosis

Research evidence - overlapping symptoms can decrease the validity of diagnosis. 

Konstantareas and Hewitt (2001) - investigated the symptoms of autistic patients and patients of SZ.

Compared 14 autistic patients and 14 with SZ (all were male).

Found not all of the SZ patients had autism symptoms but 50% of autistic patients had the negative symptoms of SZ.

Symptom overlaps makes it difficult to come to a valid diagnosis.

Leads to treatments that are not directly targeting the SZ symptoms.

Strength of validity of SZ diagnosis

Classification systems like DSM - patients have to meet more than one criteria to be diagnosed with SZ.

One criteria for SZ is the characteristic symptoms.

Another criteria is social/occupational malfunction.

Both must be met as part of the diagnosis.

Symptoms must be present for a certain time frame. 

Diagnostic criteria that covers a variety of categories - helps to make accurate diagnoses.

Especially where symptoms are not physical.

Cultural bias and SZ diagnosis

DSM-V-TR and other manuals are culturally biased as they only consider individualistic western concepts.

Hallucinations - more acceptable in African cultures because of cultural beliefs in communication with ancestors, seen as bizarre and irrational, psychiatrists are culturally biased towards what is ‘normal’ in their culture, ethnocentric.

Hearing voices - in Maori culture matakites are visionaries (prophets) who hear voices, highly respected voices are not regarded as auditory hallucinations (Lakeman 2001).

USA - Whaley (2004) says that cultural bias is responsible for the over-diagnosis of African Americans with SZ, incidence of diagnosed SZ is 2.1 %, while Americans of European origin it is 1.4 %. 

Cochrane and Sashidaran (1996) - poverty and racism experienced by immigrants and refugees is likely to lead to poor mental health.

African Americans and English people of Afro-Caribbean origin are several times more likely than white people to be diagnosed with SZ.

Cochrane (1977) - reported that the incidence of SZ in the West Indies and Britain to be similar at around 1%.

 

Evaluation - culture bias has affected diagnosis

Research evidence.

Copeland - US psychiatrists diagnosed patients with SZ 69% compared to 2% in British psychiatrists, when given the same description of symptoms. 

Shows that the background of the clinician and their own cultural biases can impact diagnosis.

Leads to patients either getting the wrong treatment or no treatment at all.

Evaluation - culture bias affects SZ diagnosis.

Research evidence.

Malgady’s - demonstrated that in traditional Costrican culture hearing voices is interpreted as spirits talking to the individual, whereas in the USA this is interpreted as a core symptoms of SZ.

Clinicians have to be mindful of the cultures and beliefs people come from.

Ensures they are not imposing their own cultural bias when diagnosing people.

Evaluations - positive from culture bias in SZ diagnosis

Practical applications.

Finding cultural biases allows for training for psychologists into the differences in interpretation of symptoms in cultures.

Improves diagnosis - by being aware of the biases they can consciously try to avoid them.

More objective in their diagnosis process.

Highlights the problems.

Leads to a reduction in these biases and to more valid diagnosis for people from different cultural backgrounds.

Evaluation - positive of culture bias in SZ diagnosis

Come up with a ‘symptom pool’ (certain symptoms for each culture).  

For example - patients from different cultures may choose to describe only physical symptoms, only emotional symptoms, or both.

Very beneficial for the validity of diagnosis of SZ - helps understand differences in symptoms in different cultures.

Means that cultural norms can be taken into consideration when a diagnosis is made.

Gender bias and SZ diagnosis

Gender of the patient (and clinician) can impact accurate diagnosis of SZ.

Men are far more likely to be diagnosed.

Women are able to cope better with the symptoms.

The tendency for diagnostic criteria to be applied differently to males and females.

Research - shows males get diagnosed with SZ more than females.

Clinicians - ignore that there are different predisposing/risk factors between males and females.

Gives them different vulnerability levels at different points in life.

May be used to explain the gender difference in the onset of schizophrenia.

Women are under-diagnosed - validity of the diagnosis of SZ is poor.

The procedures for diagnosis works well only on patients of one gender. 

Clinicians fail to consider that males tend to suffer more negative symptoms than women and have higher levels of substance abuse, or that females have better recovery rates and lower relapse rates.

Misconceptions - affect the validity of a diagnosis as clinicians are not considering all symptoms.

Evaluation - gender bias affect diagnosis of SZ.

Research evidence - Beta bias.

Cotton (2009) - women recover more and suffer less relapse than their male counterparts.

Ignoring these facts would result in gender bias (a beta bias) in clinicians not considering important factors in the diagnosis and recovery from schizophrenia.

Means that key differences that may help treatment to be tailored to help the different genders could be ignored.

Diagnosis of SZ may not be valid.

Gender differences are not considered.

Limits full understanding of the unique experiences of SZ for the different genders.

Can impact treatment plans.

Evaluation - gender bias affects SZ diagnosis

Research evidence.

Nasser (2002) - early research on SZ was conducted on men only. 

Means lots of research findings concerning treatments and explanations of the disorder may be inappropriate for women (Alpha bias).

Androcentric.

Limits our ability to generalise the finding to both males and females.

Detrimental to valid diagnosis and treatment.

Evaluation - gender bias affects SZ diagnosis.

Research evidence.

Loring and Powell (1988) - conducted a study where 290 male and female psychiatrists read 2 cases, asked to judge the condition, using standardised diagnostic criteria.

Male or no gender information - 56% were diagnosed as having SZ.

Female only 20 % were diagnosed with SZ  (but gender bias was less prominent with female psychiatrists). 

Gender of the patient impacts diagnosis as well as the gender of the clinician.

Women are more likely to be misdiagnosed with depression and anxiety.

These disorders are more commonly identified in females.

Leads to incorrect treatment.

Prolonging the illness.

Evaluation - positive of gender bias in SZ diagnosis

Practical application.

Research - used to help train psychologists to not misdiagnose females who have SZ symptoms with other disorders associated with females.

Should result in more women receiving the correct diagnosis of SZ. 

Means that male patients should not be over diagnosed and should not receive a diagnosis of SZ that is incorrect.  

Findings from studies like Loring and Powell can help to show there are biases when diagnoses are made.

Help improves the validity of the process moving forwards.

The right diagnosis leads to the right treatment offered to the patients.