ICD

Question 1

What is it

Answer 1

International statistical classification of Disease and Related Health problems
Includes physical and mental health disorders
Chapter 5 of ICD - 10 is mental and behavioural disorders

Question 2

Reliability improvements

Answer 2

Ponizovsky et al (2006)
Compared R of ICD -9 and 10
3000 patients assessed at each time point (1989,1996, 2003)
Reliability of diagnosis measured using Positive predictive value, proportion of people w same diagnosis when reassessed for SZ PPV increased 68% 1989 to 94.2% 2003
Higher figures in 2003 show increased reliability

Question 3

Reliability weakness

Answer 3

High reliability is meaningless w no validity as on its own says nothing about diagnosis

Question 4

Inter rate reliability

Answer 4

Good consistency when 2 clinicians asses same Clients w ICD 10
Galeazzi et al (2004) arranged 2 researchers to conduct joint interview to assess 100 consecutive clients for psychosomatic symptoms
Kappa value 0.69-0.97 showing high agreement which increased confidence

Question 5

Predictive Validity for schizophrenia

Answer 5

Mason (1997)
Showed diagnosis SZ w ICD-10 has good predictive validity compared to other ways
ICD-9 & 10 reasonably good at predicting disability in 99 people w SZ 13 years later measured by global assesment of functioning questionnaire
Shows initial diagnosis was meaningful and useful to predict future outcomes

Question 6

Application to diagnosis

Answer 6

WHO approach to development ICD-11 is aim to improve clinical utility
WHO conducted international survey of clinicians and found people wanted simplicity and flexibility
Suggest ICD-11 will be cautious w adding new disorders and are likely to merge difficult to diagnose ones
Makes system more friendly - increasing validity