Introduction to schizophrenia

Question 1

What is schizophrenia?

Introduction

Answer 1

A severe mental disorder where contact with reality and insight are impaired
Experienced by 1% of the population

Question 2

How does the DSM-5 classify SZ?

Introduction

Answer 2

One posotive symptom must be present

Question 3

How does the ICD-10 classify SZ?

Introduction

Answer 3

Two or more negative symptoms must be present

Question 4

What are posotive symptoms of SZ?

Introdcution

Answer 4

Additional experiences beyond those of odinary existence.
Such as halluncinations and delusions

Question 5

Hallucinations

Introduction

Answer 5

Unusual sensroy experiences
Some are realted to events in environment whereas others bear no relationship
Hallucinations can be experienced in relation to any sense

Question 6

Delusions

Introfucton

Answer 6

Irrational beliefs
Commonly involve being an important historical, political or religous figure
Another class of delusions concerns the body - A person may believe that they are under external control
Delusions can make a person behave in ways that make sense to them but are bizarre to others

Question 7

What are negative symptoms of SZ?

Introduction

Answer 7

Involve the loss of usual abilities and experiences

Question 8

Speech poverty

Introdcuction

Answer 8

Emphasis on reduction in amount and quality of speech in SZ
Accompanied by delay in person’s verbal responses during convo
DSM-5 classifies as posotive symptom - emphasis on speech disorganisation (speech is incoherent or speaker changes topic mid sentence)

Question 9

Avolition

Introduction

Answer 9

Finding it difficult to begin or keep up with goal-oriented activity
People with SZ have less motivation to carry out range of activities
Andreasen (1982) indentified 3 signs of avolition - poor hygiene, lack of persistence in work/education and lack of energy

Question 10

Issues in diagnosis & classification - Good reliability

Introduction

Answer 10

Strength
A psychiatric diagnosis is said to be reliable when diff clinicians reach same diagnosis for same individual and when same clinician reaches same diagnosis for same individual on two occasions. Osorio et al (2019) report excellent reliability for diagnosis of SZ in 180 individuals using DSM-5.
This means we can be reasonably sure that diagnosis of SZ is consistently applied

Question 11

Issues in diagnosis & classification - Low validity

Introduction

Answer 11

Limitation
One way to assess validity of psychiatric diagnosis is criterion validity. Cheniaux et al (2009) had 2 psychiatrists independently asses the same 100 clients using ICD-10 & DSM-4 crtieria and found that 68 were diagnosed with SZ from ICD and 39 from DSM
Suggests SZ is either over- or underdiagnosed accoring to diagnostic system (either way criterion validity is low)

Question 12

Issues in diagnosis and classification - Counterpoint to low validity

Introduction

Answer 12

Osorio et al, there was excellent agreement between clinicians when they used 2 measures to diagnose SZ both derived from DSM system
This means criterion validity for diagnosing SZ is good provided it takes places within one diagnostic system

Question 13

Issues with diagnosis & classification - Co-morbidity

Introduction

Answer 13

Limitation
If conditions occur together a lot of the time, this calls into question the validity of their diagnosis and classification - might be one condition. SZ commonly diagnosed with other conditions. Buckley et al found that half of those diagnosed with SZ had a diagnosis of depression or substance abuse as well
This is problem for classification as it means SZ may not exist as distinct condition and is problem for diagnosis as at least some diagnosed with SZ may have unusal cases of conditions like depp

Question 14

Issues with diagnosis and classification: Gender bias in diagnosis

Introduction

Answer 14

Limitation
Fischer and Buchanan (2017) - since 1980s mean have been diagnosed with SZ more commonly than women (1.4:1). One explanation is that women are less vulnerable because of genetic factors. Cotton et al (2019) - Seems more likely that women are underdiagnosed because they have closer relationships so get support. Leads to women with SZ fucntioning better than men.
This underdiagnosis is a gender bias and means women may not be receiving treatment and services that benefit them.

Question 15

Issues with diagnosis and classification: Culture bias in diagnosis

Introduction

Answer 15

Limitation
Some symptoms of SZ (hearing voices) have diff meanings in diff cultures. Pinto & Jones (2008) - British people of African-Caribbean origin are up to 9x more likley to receive a diagnosis than white Brits, although people living in A-C countries are not. Most likely explanation for this is culture bias in diagnosis of clients by psychiatrists from diff cultural backgrounds. Escobar (2012) - leads to overinterpretation of symptoms in black Brits.
This means British A-C people may be discriminated against by culturally-biased diagnostic system

Question 16

Issues with diagnosis & classification: Symptom overlap

Introdcution

Answer 16

Limitation
Considerable overlap between symptoms of SZ and symptoms of other conditions. For example, both SZ and bipolar involved + (delusions) and - (avolition) symptoms. In terms of classification this suggests SZ and bipolar may be variations of a single condition. In terms of diagnosis it means SZ is hard to distinguish from bipolar
Suggests that SZ may not exist as a distinct condition and that even if it does it is hard to diagnose - both classification and diagnosis are flawed.