classification systems: ICD

Question 1

what is the ICD?

Answer 1

• includes both physical and mental disorders
• unlike DSM, ICD has received many revisions
• provides a ‘common language’ so data from other countries can be compared

Question 2

how are mental disorders coded in the ICD-10?

Answer 2

• each disorder has a code starting with F
• disorders listed consecutively and there are 11 sections
• each section has leftover codes, allowing new disorders to be added without having to recode other disorders
• system attempts to be comprehensive enough to include all known conditions and avoid repetition

Question 3

how do you make a diagnosis using the ICD-10?

Answer 3

1. clinician selects key words from interview that relate to symptoms
2. clinician can look up up symptoms in index or go straight to section
3. uses other symptoms to locate subcategory

Question 4

what are the improvements that have been made?

Answer 4

• culture bias means clients in one culture may be given different diagnosis to those in others because of different norms and language
• ICD available in different languages and in appropriate cultural forms
• helped reveal inconsistencies and overlaps between disorders in ICD> removed
• ICD-10 clear, simple and organised

Question 5

is the ICD reliable?

Answer 5

-a longitudinal study found PPV scores increased by 26% for SZ, and 8% for anxiety disorders from the late 1900’s
-improved reliability and shows increased disorders from ICD-9 has not detracted from reliability of diagnoses
AND , compare to Reigers 0.28 for mood disorders> ICD might be better for these disorders

Question 6

BUT…

Answer 6

for childhood and personality disorders, PPV’s were as low as 55%.
might seem high compared to DSM, but these figures are on agreement on category levels not specific disorders
SO, ICD might not be reliable for specific diagnoses

Question 7

strength with reliability?

Answer 7

good agreement between clinicians when assessing same clients using ICD-10
EG. in a study where 2 researchers conducted a joint interview to assess 100 clients for psychosomatic symptoms - kappa values ranged from 0.70 to over 0.95
SO, encourages confidence for using ICD-10 for some disorders

Question 8

does the ICD have good validity?

Answer 8

-Mason has shown diagnosis of SZ using ICD-10 has good predictive validity
Study compared different ways of making diagnosis and ICD 9 and 10 were good at predicting disability in 99 people with SZ 13 years later
SO, initial diagnosis was useful in predicting future outcomes

Question 9

application?

Answer 9

to develop ICD-11, aim is to improve clinical utility of the system
ICD-11 task force will be cautious about adding new disorders and are likely to merge disorders that are difficult to diagnose
SO, system should be more ‘user friendly’ and easier to use > validity should improve