When diagnosing physical health problems, doctors examine and talk to their patients, to create lists of signs and symptoms. Signs are objective indicators like a rash or a high temperature, while symptoms are the patients’ subjective experiences, e.g. sore throat or tingling sensation. This information is used to reach a diagnosis, which informs treatment and the expected prognosis.

Many Westerners believe that mental disorders can be addressed in a similar way and manuals such as the ‘Diagnostic and Statistical Manual of Mental Disorders’ (DSM) and the ‘International Statistical Classification of Diseases and Related Health Problems’ (ICD) provide checklists of symptoms that commonly cluster together allowing practitioners to identify and diagnose hundreds of different disorders.

The process of diagnosis often involves ruling out disorders for which the person does not match the description, in order to reach the disorder which is the ‘best fit’ for the individual. Finding an appropriate diagnosis can take the individual one step closer to specialised support and treatment.

In this section we will learn about two classification systems, the DSM and the ICD.

Describing the DSM and ICD

Reliability and diagnosis

Validity and diagnosis

Cultural issues affecting the validity of diagnosis

R and V Revision materials including model answers

Clip about the http://www.dsm5.org/psychiatrists/practice/dsm

My detailed PowerPoint: classification of disorders (1)

Wider reading

An article comparing the DSM and ICD: https://pdfs.semanticscholar.org/4c80/d37e2650c3e96249bae4638f06eaf96f53d9.pdf

Assessment Questions

SAQs

1. Describe what is meant by the term ‘classification systems’ with regard to mental health (2)
2. Explain how a doctor might use the  DSM IV TR or DSMV to make a diagnosis (3)
3. Explain one difference between the DSM IV TR or DSMV and the ICD (2)
4. Compare the DSM IV TR or DSMV and the ICD (4)
5. Explain one strength of the DSM IV TR or DSMV (2)
6. Explain one  weakness of the DSM IV TR or DSMV (2)
7. Describe one way in which a doctor might determine whether a diagnosis is reliable? (2)
8. Describe one way in which a doctor might determine whether a diagnosis is valid? (2)
9. Explain one issue that can affect the reliability of diagnosis (2)
10. Explain one issue that can affect the validity of diagnosis (2)
11. For many years clinicians have tried to improve the standard of diagnosis for people with mental health issues. Using research evidence, explain issues relating to the reliability and validity of diagnosis. (5)

ERQs – 8 markers

1. Edward is worried about his neighbour Bert, whose wife died a few months ago. Bert has received a diagnosis of major depressive disorder but Edward is worried. He has heard Bert moving furniture around all night long and shouting at someone despite living alone. Bert has also been lining up countless containers in the back garden to collect rainwater which he says he uses to fill his bath as he is worried someone is trying to poison his water supply. Discuss possible reason’s why Bert’s diagnosis may not be valid and how validity could be established (8)
2. Evaluate the reliability of the DSM IV TR or DSMV (8)
3. Evaluate the validity of the DSM IV TR or DSMV (8)
4. Evaluate the reliability of the ICD (8)
5. Evaluate the validity of the ICD (8)

ERQs – 20 markers

1. Evaluate the classification systems (DSM IV TR or DSMV, and/or ICD) for mental health, including reliability and validity of diagnoses (20)
2. Edward is worried about his neighbour Bert, whose wife died a few months ago. Bert’s doctor has diagnosed him with a mental disorder using the DSM but Edward is not convinced that the diagnosis is correct. Bert can be heard pushing furniture around all night long and shouting at someone despite living alone. He has also been seen lining up countless containers in the back garden to collect rainwater; he has told Edward that he thinks someone is trying to poison his water supply. To what extent do you think Edward’s concerns about the reliability and validity of Bert’s diagnosis are justified? (20)

20 mark classification randomiser: Put this PowerPoint into ‘slideshow mode’ and it will flick between two 20 markers; hit ‘control S’ and it will choose one for you!