Diagnosing Schizophrenia
Schizophrenia disrupts the mind’s ability to function:
Schizophrenia is a thought process disorder. It’s characterised by disruption to a person’s perceptions, emotions and beliefs
The onset of schizophrenia can be acute (sudden onset, where changes within a few days), or chronic (a gradual deterioration in mental health that develops slowly over time).
Males and females are equally affected. In males, schizophrenia usually develops in their late teens or early 20s, while females tend to develop it 4 or 5 years later. Overall, 0.5% of the population is affected
It’s thought that schizophrenia isn’t a single disorder but that there are various subtypes- however, there still isn’t an agreed definition
Schizophrenia has lots of different clinical characteristics
Perpetual symptoms:
Auditory hallucinations- hearing things that aren’t there. People often hear voices saying abusive things
Auditory hallucinations are the most common type of hallucination in schizophrenia, but there are other types of hallucination too. Sometimes people see, feel, smell, or taste things that aren’t there
Social symptoms:
Social withdrawal- not taking part in or enjoying social situations
People might be aloof or avoid eye contact
Cognitive symptoms:
Delusions- Believing things that aren’t true. People can have delusions of grandeur (where they believe they’re more important than they are, e.g. that they're king) or of paranoia and persecution (where they believe people are out to get them). Some people with schizophrenia also experience delusions of control- they believe that their behaviour is being controlled by someone else. For example, thought insertion is when someone feels that thoughts are being put into their head. Thought withdrawal is when they believe that someone is removing their thoughts. They might also believe that people can read their thoughts- this is thought broadcasting
Language impairments- irrelevant and incoherent speech. People often show signs of cognitive distractibility, where they can’t maintain a train of thought. They might also repeat sounds others say (echolalia), speak nonsense or gibberish (word salad), speak in nonsensical rhymes (clang associations), experience speech poverty (give brief replies in conversation and show no extra, spontaneous speech) and invent words (neologisms)
Affective/Emotional Symptoms:
Avolition- A lack of drive, motivation or interest in achieving goals
Lack of interest in hygiene and personal care
Lack of emotion- reacting in an inappropriate way, e.g. laughing at bad news
Behavioural symptoms:
Stereotyped behaviours- Continuously repeating actions, which are often strange and don’t have a purpose
Psychomotor disturbance- Not having control of your muscles. People may experience catatonia, where they sit in an awkward position for a long time. In this state, people will sometimes stay in whatever position they’re put in (so if you lift their arm over their head it’ll stay like that until you move it back). A catatonic stupor involves lying rigidly and not moving around for long periods of time. People are conscious during these episodes and can remember that was going on around them, although they don’t seem aware of it at the time
Schizophrenia has positive and negative symptoms:
The symptoms experienced by people with schizophrenia can be split into two types- positive and negative symptoms. Positive and negative symptoms don’t mean they’re ‘good’ or ‘bad’ symptoms. They refer to whether experience and behaviour are extra (positive) or lacking (negative)
Positive: This is where people experience something, feel that something is happening to them, or display certain behaviours- they are extra experiences and behaviours that are not normally there.
Hallucinations
Delusions
Jumbled speech
Disorganised behaviours
Negative: This is where people don’t display ‘normal’ behaviours- these symptoms are a lack of experiences or behaviours which are normally there. They all start with A
Speech poverty
Lack of emotion
Avoliation (becoming disinterested)
Lack of ability to function normally
Positive symptoms:
Delusions:
These are firmly held irrational beliefs that result from distortions of reasoning or misinterpretations of a person's experiences.
being watched or followed (e.g. paranoia), being persecuted by the Government, aliens or superpowers.
Can concern the body - may believe a part of them is under external control.
Some delusions can lead to violence
Hallucinations:
These are abnormalities of perception that can occur in any of the senses. Some hallucinations are related to events in the environment, whereas others bear no relationship to what the senses are picking up from the environment.
Auditory hallucinations (hearing voices) are most common. These "voices" often insult the person, comment on his or her behaviour or give commands.
Visual hallucinations are the second most common type.
The sufferer may see distorted facial expressions or people or animals that are not there.
Disorganised speech/thinking:
This symptom is considered central to Schizophrenia, It causes people to have difficulty concentrating and maintaining a train of thought, which manifests in the way they speak. People with disorganized speech might speak incoherently, respond to questions with unrelated answers, say illogical things, or shift topics frequently.
Disorganised Behaviour:
This behaviour includes difficulties with activities of daily living, unpredictable agitation or behaviour that appears bizarre.
Negative symptoms:
Avolition or ‘Apathy’:
Can be described as finding it difficult to begin or keep up with goal-directed activity, i.e actions performed in order to achieve a result. Sufferers of Schizophrenia often have sharply reduced motivation to carry out a range of activities
Andreason (1982) identified 3 identifying signs of avolition: poor hygiene and grooming, lack of persistence in work or education and lack of energy
Alogia (speech poverty:
ICD 10 recognises this as a negative symptom due to a reduction in amount and quality of speech.the
Individuals display Delays in their verbal responses during
conversation.
Sometimes this can be detected through empty or disinterested replies to questions.
DSM focuses more on speech disorganisation- incoherent speech (+ symptom)
Affective Flattening:
Affective flattening (also known as flat effect) can be a negative symptom of schizophrenia, meaning that your emotional expressions do not show. You may speak in a dull, flat voice and your face may not change. You may avoid eye contact and inhibit body language. You also may have trouble understanding emotions in other people.
The DSM classifies mental disorders:
The DSM is the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders
It contains a list of mental health disorders, outlining the symptoms themselves and how long these symptoms should be present, to result in a diagnosis
It aims to give a diagnosis of mental disorders reliability and validity
Reliability: This is how far the classification system produces the same diagnosis for a particular set of symptoms. In order for a classification system to be reliable the same diagnosis should be made each time it’s used. This means that different clinicians should reach the same diagnosis
Validity: Is whether the classification system is actually measuring what it aims to measure
Descriptive validity: How similar individuals diagnosed with the disorder are
Aetiological validity: How similar the cause of the disorder is for each sufferer
Predictive validity: How useful the diagnostic categories are for predicting the right treatment
For a person to be diagnosed as having schizophrenia, the DSM states that they must show at least two of:
Delusions
Hallucinations
Disorganised speech
Disorganised or catatonic behaviour
Any negative symptoms
*At least one of their symptoms must be from the first three of these. Their symptoms have to have been present for at least six months, with at least one month of active symptoms
Reliability in diagnosis and classification:
Inter-rater reliability is measured by a statistic called a kappa score.
A score of 1 indicates perfect inter-rater agreement;
A score of 0 indicates zero agreement.
A kappa score of 0.7 or above is generally considered good.
In the DSM-V field trials (Regier et al 2013), the diagnosis of schizophrenia had a kappa score of only 0.46.
There can be problems with the reliability and validity of diagnoses:
Problems with reliability:
Schizophrenia diagnosis may be affected by cultural bias.
For example, Harrison et al (1984) showed that there was an over-diagnosis of schizophrenia in West Indian psychiatric patients in Bristol. No research has found any cause for this, so it suggests that the symptoms of ethnic minority patients have been misinterpreted. This questions the reliability of the diagnosis of schizophrenia- it suggests that patients can display the same symptoms but receive different diagnoses because of their ethnic background
Cultural bias has also been shown to stem from the medical staff themselves. Copeland et al (1971) found that 69% of American psychiatrists in the study diagnosed a particular patient (shown in a video) as having schizophrenia compared with only 2% of British psychiatrists asked to diagnose the same patient
Reliabily diagnosing schizophrenia can also be difficult due to gender bias. Loring and Powell (1988) conducted a study in which 290 psychiatrists were asked to diagnose the same two patients. When they were told the patient was male, 56% diagnosed the patient as having schizophrenia. If they were told the patient was female, this dropped to around 20%, despite identical symptoms. This gender bias wasn’t as clear if the psychiatrists were female. So, gender bias comes not only from the gender of the patient but also from the gender of the practitioner
Problems with validity:
Rosenhan (1973) conducted a study where people with no mental health problems got themselves admitted into a psychiatric unit by saying they heard voices- they became pseudopatients. Once they’d been admitted they behaved ‘normally’. However, their behaviour was still seen as a symptom of their disorder by the staff on the unit. For example, one pseudopatient who wrote a diary was recorded as displaying ‘writing behaviour’. This questions the validity of the diagnosis of mental disorders- once people are labelled as having a disorder, all of their behaviour can be interpreted as being caused by the disorder
Symptom overlap can also cause problems with the validity of diagnosis. Lots of the most common symptoms of schizophrenia are also found in other disorders. For example, avolition is also a symptom of depression. This makes it hard to determine which disorder the patient may have
Comorbidity can be a problem too:
Comorbidity can also be an issue in making a reliable and valid diagnosis of schizophrenia.
Comorbidity means having two or more conditions at the same time. For example, patients with schizophrenia may also have depression. Having more than one condition makes it really difficult for healthcare professionals to diagnose schizophrenia as a distinct mental illness.
It could be that some of their symptoms belong to one known disorder, but that the others belong to an untreated mental disorder which hasn't been recognised yet.
Reliability and validity: Culture bias:
One of the main characteristics of schizophrenia, "hearing voices also appears to be influenced by cultural environment.
Luhrman et al (2015) interviewed 60 adults diagnosed with schizophrenia, 20 each in Ghana, India and the US. Each was asked about the voices they heard.
Strikingly, while many of the African and Indian subjects reported positive experiences with their votes, describing them as playful or offering advice, not one American did.
Rather the US subjects were more likely to report the voices they heard were violent and hateful - and indicative of being sick.'
Luhrman suggests that the harsh, violent voices so common in the West may not be an inevitable feature of schizophrenia.
This suggests that schizophrenia has a lack of consistent characteristics.
Further support for cultural bias in diagnosis and classification:
Escobar (2012) found that African-American and English Afro-Caribbean ethnicities are several times more likely than white people to be diagnosed with SZ.
Rates in Africa and W. Indies are not very high. These individuals are often diagnosed by white psychiatrists - (who may already view hearing voices as negative, therefore overinterpret symptoms and distrust the honesty of black people during diagnosis)
Harrison et al (1984) found p's of West Indian origin were overdiagnosed with SZ by white psychiatrists in Bristol,
In contrast, Copeland et al (1971), described a patient to 134 US and 194 British psychiatrists. 69% of the US diagnosed SZ but only 2% of British psychiatrists gave Sz a diagnosis.