Evaluation Schizophrenia

Question 1

Evaluation for validity

Answer 1

Research support for gender bias in diagnosis

• Loring and Powell – randomly selected 290 male and female psychiatrists to read two case vignettes for patients behaviour, they were then asked to offer their judgement on these individuals using standard diagnostic criteria, when they were described as males or no information was given about their gender 56% gave diagnosis of schizophrenia however when they were female only 20% were diagnosed
• Not as evident among female psychiatrists – affected by gender of clinicians as well

The consequences for co-morbidity

• A number of studies have examined single co-moralities with schizophrenia but these involved small sample sizes
• US study Weber et al looked at 6y million hospital discharge records to calculate co-morbidity rates, psychiatric and behaviour related diagnosis accounted for 45% of co-morbidity, also found evidence of many co-morbid non psychiatric diagnoses
• Many patients with primary diagnosis of schizophrenia were diagnosed with medical problems such as asthma, hypertension and type two diabetes

Differences in prognosis

• No evidence that they share the same outcomes when they are diagnosed with the same symptoms
• The prognosis for patients diagnosed with schizophrenia varies with about 20% recovering to their previous level of functioning and 10% showing a long lasting improvement and 30% showing some improvement with relapses
• It has little predictive validity and some people never recover
• What does influence outcome is more to do with gender, and psycho-social factors such as social skills academic achievement and family tolerance

Question 2

Evaluation of reliability

Answer 2

Lack of inter-rater reliability

• Despite the claims for increased reliability in the DSM, there is still little evidence that the DSM is used with high reliability by mental health clinicians
• Whaley – found inter-rater reliability correlations in the diagnosis of schizophrenia are illustrated in the Rosenhan study

Unreliable symptoms

• Only one of the characteristics are required, this creates problems for reliability
• When 50 senior psychiatrists in in the US were asked to differentiate between bizarre and non-bizarre delusions they produced inter-rater reliability correlations of only 0.4 forcing the researchers to conclude that even this central diagnostic requirement lacks sufficient reliability for it to be a reliable method of distinguishing between schizophrenic and non-schizophrenic patients

Cultural differences in the diagnosis of schizophrenia

• There are Racial and cultural differences in the diagnosis,
• The prognosis for members of ethnic minority groups may actually be more positive than for majority group members
• Ethnic minority groups experience less distress associated with mental disorders because of the protective characteristics and social structures
• Brekke and Barrio found evidence to support this hypothesis in a study in 184 individuals diagnosed with schizophrenia or a schizophrenia spectrum disorder this sample was drawn front wo non-white minority groups and a majority group
• They found that non-minority groups were consistently more symptomatic than members of the two ethnic minority groups findings which supported the ethnic culture hypothesis

Question 3

Evaluation of genetic factors

Answer 3

Common rearing factors may explain family similarities

• Research has shown that schizophrenia appears to run in families, supporting the argument for genetic basis
• Researcher have now accepted it may be due to common rearing patterns for example research on expressed emotion has shown that the negative emotional climate in some families may lead to stress beyond a individuals coping mechanisms leading to a schizophrenic episode

MZ twins encounter more similar environments

• Crucial assumption which underlies all twin studies is that the environment that they grow up in is the same therefore the concordance rate is due to genetic similarity and not environmental similarity
• Joseph 2004 points out that the environments could be different that they grow up in therefore concordance rates highlight the different environmental differences and not the genetic differences or similarities

Adoptees may be selectively placed

• Central assumption of adoption studies is that Adoptees are not selectively placed, adoptive parents who adopt children with schizophrenic biological parent are not different from those that adopt a normal parented child
• Joseph claimed that this is unlikely to be the case as US and Denmark adoptive parents are informed of the genetic background prior to adoption, therefore they are less likely to be adopted

Question 4

Evaluation of the Dopamine hypothesis

Answer 4

evidence from treatment

• Much evidence comes from the success of drug trials, for example treatments that attempt to change levels of dopamine activity in the brain, basic mechanism of antipsychotic drugs reduce the effects of dopamine and therefore reduce the symptoms of schzioprhenia
• Leucht et al – carried out a meta-anaylsis of 212 studies that had analysed the effectiveness of different antipsychotic drugs compared with a placebo, they found that all the drugs tested were significantly more effective than placebo in the treatment of positive and negative symptoms

Inconclusive supporting evidence

• Moncrieff 2009 claims that evidence for dopamine levels are not conclusive
• Stimulate drugs can cause schizophrenia episodes and they are known to affect neurotransmitters other than dopamine
• Evidence for dopamine concentrations in the post-mortem brain tissue has either been negative or inconclusive
• Factors that lead to dopamine release such as stress and smoking have never been considered

Challenges to the dopamine hypothesis

• Noll 2009 – claims there is strong evidence against the original dopamine hypothesis and the revised dopamine hypothesis
• Argues that antipsychotic drugs do not alleviate hallucination sand delusions in 1/3 of those experiencing them
• Points out that hallucination and delusions are present despite dopamine levels being normal
• Blocking D2 has little effect on symptoms therefore other neurotransmitter systems are responsible for the positive symptoms

Question 5

Evaluation of family dsyfunction

Answer 5

family relationships
- Tinari et al – adopted children who had schizophrenic biological parents were more likely to become ill themselves than those with non-biological schizophrenic parents, differences only emerged in situations where the adopted family was rated as disturbed

Double bind theory

• Berger 1965 found that schizophrenics reported a higher recall of double blind statements by their mothers than non-schizophrenics
• May not be reliable as recall is affected by their schizophrenia

individual difference in vulnerability

• Not all patients who live in high EE families relapse, and not all patients who live in low EE homes avoid relapse
• Altorfer et al have found individual differences in response high EE like behaviours, found ¼ of the patients they studies showed no physiological responses to stressful comments from their relatives, vulnerability to the influences of high EE may also be psychologically based
• Lebell et al suggests how patients appraise the behaviour of their relatives is important, in cases where high EE behaviours are not perceived as being negative or stressful they can do well regardless of the family environment

Question 6

Evaluation of cognitive explanations

Answer 6

supporting evidence

• Sarin and wallin reviewed recent research evidence relating to the cognitive model of schizophrenia
• They found supporting evidence that positive symptoms of schizophrenia have their origins in faulty cognition
• For example delusional patients were found to show various biases in their information processing such as jumping to conclusions and lack of reality testing
• Schizophrenic individuals with hallucinations were found to have impaired self-monitoring and also tended to experience their own thoughts as voices

support from evidence of cognitive therapies

• Claim that symptoms of schizophrenia have their origin in faulty cognition is reinforced by the success of cognitive based therapies for schizophrenia
• Patients encouraged to evaluate the content of their delusions or of any voices and to consider ways in which they may test the validity of their faulty beliefs
• Effectiveness was demonstrated in the NICE review of treatments – found consistent evidence that when compared with the treatment by antipsychotic medication CBT was more effective in reducing symptom and increasing social functioning

integrated model of schizophrenia

• Howes and Murray – addressed the problem of the integrated model dealing in adequately with multiple aspects of the disorder, they created an integrated model and argue that early vulnerability factors such as genes, birth complications together with exposure to social stressor and the dopamine system can cause schizophrenia
• Results in hallucinations and psychosis

Question 7

Evaluation of drug treatment

Answer 7

anti-psychotic versus placebo
- Leucht et al – carried out a meta-analysis of 65 studies between 1959 and 2011 involving nearly 6000 patients, all patients had been stabilised or either on typical or atypical anti-psychotics, some were taken of the antipsychotic and given a placebo instead, the remaining patients remained in the antipsychotic, within 12 months 64% on the placebo relapsed and only 27% relapsed on the antipsychotic

extrapyrimidal side effects

• Typical antipsychotic drugs can sometimes produce movement problems for the patients
• Drugs impact extrapyramidal side of the brain, they can experience symptoms like the Parkinson’s disease
• Or they could get tardive dyskinesia this is involuntary movement of the tongue face and jaw, these are distressing for the patients so other drugs have to be given to control them

ethical problems with typical anti-psychotics

• If side effects, deaths and psychosocial consequences were taken into account a cost-benefit analysis of its advantages would be negative
• In the US a large out of court settlement was given to a tardive dyskinesia sufferer on the basis of article 3 of the human rights act as its is inhuman and degrading treatment

advantages of atypical over typical anti-psychotics

• Fewer side affects
• Less likely to produce extrapyramidal side effects
• More likely to continue with there medication which means they are more likely to see a reduction in their symptoms

are atypical antipsychotics better

• Crossley et al – meta-analysis of 15 studies to examine the efficiency and side effects of atypical versus typical antipsychotics in the early phase treatment of schizophrenia, they found no differences between atypical and typical in terms of their affect on treatment but did not there side effects experienced
• Atypical – gained more weight than those on typical
• Typical – experienced extrapyramidal side effects

motivation deficits

• Ross and Read 2004 – argued that when some people are prescribed antipsychotic medication it reinforces the view that there is something wrong with them, prevents the individual from thinking about possible stressors
• Reduces their motivation to look for possible solutions that might alleviate these stressors and reduce suffering

Question 8

Evaluation of cognitive behavioural therapy

Answer 8

advantages of CBT over standard care

• NICE review od treatments found consistent evidence that when compared with standard care, it was effective in reducing rehospitalisation rates up to 18 months following the end of treatment
• Reducing symptom severity and there is improvement in social interaction and functioning
• However most studies of the effectiveness of CBTp have been conducted with patients treated at the same time as antipsychotic medication therefore difficult to assess on its own

effectiveness of CTBp is dependent on the stage of the disorder

• More effective when available at specific stages of the disorder and when the delivery of the treatment is adjusted to the stage that they are on
• Addington and Addington 2005 – claimed that in the initial acute phase of schizophrenia self-reflection is not appropriate but when psychotic symptoms stabilise the individual benefit more from group based CBTp, this normalises the experience by meeting other individuals with similar issues
• If they have more experience of their schizophrenia then they benefit more from individual CBTp

lack of availability

• Predicted that only 1 in 10 get access to the therapy
• Haddock et al in the North West of England found that out of 187 schizophrenic patients only 13 had been offered CBTp and of those who are offered it as a treatment a significant number refuse or fail to attend therapy sessions

benefits may have been overstated

• More recent and methodological sound meta-anaylses of the effectiveness of CBTp as a sole treatment for schizophrenia suggest that its effectiveness may be lower than thought
• Jauhar et al – revealed that only a small therapeutic effect on the key symptoms of schizophrenia
• Small affects disappeared when symptoms were assessed as blind
• Studies investigating CBTp have similar design flaws and lack of originality as they are usually taking antipsychotic drugs

problems with the meta-analysis of studies

• Failure to take into account study quality
• Some studies fail to randomly allocate participants to either a CBTp or control conditions
• Others fail to mask the treatment condition for interviewers carrying out assessments of symptoms and general functioning, but all of these studies are grouped together for a meta-analysis
• Juni et al concluded that there was clear evidence that the problems associated with methodologically weak trials translated into bias findings about the effectiveness
• Wykes et al found the more rigorous the study the weaker the effect of CBTp

Question 9

Evaluation of family therapy

Answer 9

why is family therapy effective

• Pharoah et al – meta-analysis established that family therapy can be effective in improving clinical outcomes such as mental state and social functioning
• Increases medication compliance as they are more likely to reap the benefits of medication

methodological limitations of family therapy

• Problem with random allocation – although all 53 studies claimed to have randomly allocated participants to treatment conditions the researchers noted that a large number of studies used in the review were from the peoples republic of China, they stated that they used random allocation but they did not
• Lack of blinding – possibility of observer bias where raters were not blinded to the condition to which people were allocated, 10 studies reported that no blinding was used and 16 did not report at all

economic benefits

• NICE reviewed that it saves a significant amount of cost compared to standard care, less likely to relapse so less hospital rates
• Reduces relapse for a long time therefore saving costs in family therapy

impact on family members

• Lobban et al – analysed the results of 50 family studies and included an intervention to support relatives
• 60% reported a positive impact of the intervention on at least one outcome for relatives, for example coping and problem-solving skills, as well as family functioning and relationship quality
• Methodological studies were generally poor so it made it difficult to distinguish between effective and from ineffective interventions

is family therapy worthwhile

• Garety et al failed to shown any better outcomes for patients given sessions of family therapy
• Individuals in both groups were found to have unexpectedly low rates of relapse compared with the no carer group, the carers did not show expressed emotion
• He suggested for many people that family intervention may not improve outcomes further than a good standard of treatment as usual

Question 10

evaluation of token economy

Answer 10

research support

• Dickerson et al – provided research support for the effectiveness of token economies in a psychiatric setting, they reviewed 13 studies of the use of token systems in treatment
• 11 had reported beneficial effects due to the token economies
• Therefore they had an overall beneficial effect, however they did caution that many of the studies showed shortcomings that limited their impact in the overall assessment

difficulty assessing the success

• Comer 2013 – suggests that a problem is that the use is uncontrolled, when a token economy system is introduced all patients are brought into the system rather than an experimental group therefore patients improvements can only be compared with their past behaviours rather than a control group
• May be due to an increase in staff attention that leads to better effectiveness and improvement

less useful for patients living in the community

• Only works in a hospital setting where it can be regulated
• Corrigan 1991 argues that there are problems administering it in a community as its difficult to monitor and reward and control as they only receive treatment for a few hours a day so therefore can only be used for part of the day and cannot be maintained beyond the environment

ethical concerns

• In order to make reinforcement effective they may exercise control over primary reinforcers such as food or access to activities
• Patients then may exchange tokens if they display target behaviour
• Generally accepted that all humans should have an access to food and hygiene and they cannot be violated regardless of positive consequences

does it actually work
- McMonagle and Sultana suggests that the token economy may be important if randomised trials could be carried out but this is only important in developing countries were it is still practised therefore they could see how effective it actually is

Question 11

evaluation of the interventionist approach

Answer 11

diathesis may not be exclusively genetic

• Most models emphasis the idea in terms of genetic influences alone which are assumed to cause neurochemical abnormalities that increase the risk of schizophrenia, this increased risk can result from brain damage from environmental factors
• They may develop a vulnerability to schizophrenia from birth difficulties
• Verdoux et al – estimated that the risk of developing schizophrenia later in life for individuals who experienced complications at birth is four times likely than those who had no complications

urban environments are not necessarily more stressful

• Romans-Clarkson et al disagreed with Vassos et al, as they found no mental health differences between urban and rural women in New Zealand
• Also noted these differences disappeared after adjusting for the socioeconomic differences from the two groups, therefore it could be social adversity that causes the problem and urbanisation is an over-simplification

difficulties determining causal stress

• Things that happen early in life can influence how we respond to stressors later and increase there susceptibility to the disorder
• Hammen 1992 argues that the maladaptive methods of coping with stress in childhood and throughout development means that the individual fails to develop effective coping skills which compromises their resilience and increases vulnerability
• Therefore they make life generally more stressful for the individual and trigger mental illness

limitations of the Tinari et al study

• Assessment of adoptive family functioning – they were assessing the family at only one point in a given time, fails to reflect developmental changes in family functioning
• Reciprocal interactions between the adoptive family and adoptees makes it impossible to determine how much of the stress is observed is assigned to the family and how much the adoptee causes

implications for treatment

• Control factors that could lead to schizophrenia
• Borglum et al – found that women infected with cytomegalovirus during pregnancy were more likely to develop a child with schizophrenia but only if mother and child carried agene defect therefore anti-viral medicine can prevent the onset of schizophrenia in the offspring of women to have the gene deficit.