Classification & Symptoms Flashcards
What are the two systems for classification
1) international ICD-10
2) American DSM-5
What’s the main difference in classification criteria between ICD-10 and DSM-5
In DSM-5 there must be a positive symptom whereas ICD-10 2 negative symptoms if enough
What’s the the main difference between recognising sub-types between ICD and DSM
ICD recognises sub types between the two whereas DSM does not
Define positive symptoms
Atypical symptoms experienced in addition to normal experience
Define negative symptoms
Atypical experiences that represent a loss of usual experiences
Name 2 positive symptoms
1) hallucinations
2) delusions
Describe hallucinations
They can be experienced in relation to any sense
Describe delusions
May or may not lead to aggression
Name 2 negative symptoms
1) avolition (apathy)
2) speech poverty
Deceive avolition
Finding it hard to keep motivated toward goal-directed activity
Who identified three signs of avolition and name these
Anderson (1982)
1) poor hygiene and grooming
2) lack of persistence in work or education
3) lack of energy
Describe speech poverty
Characterised by changes in patterns of speech. Includes a reduction of quality and quantity of speech as well as a delay in response during conversation
What is the DSMs take on speech poverty
Places emphasis on speech disorganisation in which speech becomes incoherent and topic changes mid sentence. This is classed as a positive symptom rather than a negative
Define inter-rater reliability
The extent to which two different assessors agree on their assessment
Describe study into reliability of diagnosis
Cheniuax et al. (2009)
1) had two psychiatrists independently diagnose 100 patients with both DSM and ICD
2) inter-rater reliability was poor
3) DSM: 26 & 13
4) ICD: 44 & 24
5) poor reliability is a weakness
How does the ability study show poor validity
1) validity of a diagnosis is assessed by criterion validity; do different assessment systems arrive at same diagnosis.
2) study clearly shows wither ICD or DSM under or over diagnoses.
3) poor validity
Describe co-morbidity
The occurrence of two conditions together. When two conditions are frequently diagnosed together calls into question the validity of classifying two conditions separately
Describe study into co-morbidity
Backley et al. (2009)
1) concluded that around 50% of SZ patients also diagnosed with depression, 47% with PTSD
2) 23 % OCD
3) calls into question the difference between the two conditions
Symptom overlap reduces validity of diagnosis
- both SZ and Bipoalar have positive symptoms of delusions and both have negative of avolition
- Under DSM or ICD some would be diagnosed with SZ and some Bipoalr
Gender bias
- Men have been diagnosed more
- Could be genetics but could also be gender bias in diagnosis
- Women better handle family and work relationships so they may be under diagnosed as are better able to cope
