Clinical diagnosis and classification systems (Clin)

Question 1

define classfication

Answer 1

the process of identifying symptoms that can be used to define a particular disorder

Question 2

define a classification system

Answer 2

checklist of signs and symptoms which help a clinician reach a diagnosis

Groups smaller disorders into “families”, specifiying the different symptoms so that the correct diagnosis is made
- e.g. depressive disorders: major depressive disorder, disruptive mood dysregulation disorder etc
- e.g. anxiety disorders: generalised anxiety disorder, specific phobias, obsessive compulsive disorder etc

Question 3

What is the DSM-5?

Answer 3

• over 300 mental + behavioural disorders
• grouping them into 22 categories
• is regularly updated (~**10 **years) to reflect evolving understanding of mental health.
  - Mental health disorders no longer valid, removed
  - Newly defined disorders are added
• Most recent revision (DSM-5-TR) published 2022 includes new diagnoses (e.g. prolonged grief disorder) + clarifying modifications to criteria for over 70 disorders
• Includes comprehensive review of impact of racism + discrimination on diagnosis + manifestations of mental disorders

Question 4

What is the ICD?

Answer 4

• International Statistical Classification of Disease (ICD)
• Contains both the mental + physical disorders + is produced + regularly revised by the World Health Organisation (WHO)

Question 5

How is the DSM-5 structured?

Answer 5

contains three section:
- Section 1: gives information on how use DSM-5 system
- Section 2: details different disorders in categories which linked by similar causes or symptoms.
- E.g. For schizophrenia, diagnosis no longer made in subtypes (paranoid, catatonic etc.) – instead, dimensional assessment used, focuses on level, number + duration of symptoms
- Section 3: Has suggestions for new disorders which are being further investigated for full inclusion in manual. Also includes information about impact of culture on how symptoms are presented and communicated. Important when the clinician + patient are from different cultures.

Question 6

How is the ICD structured?

Answer 6

• Chapter 5 of ICD entitled Mental and Behavioural Disorders + uses a coding system to categorise different disorders.
• 11 sections e.g. Schizophrenia, schizotypal and delusional disorders is one section + within this different subtypes of these disorders are listed + coded.
  - For example, Schizophrenia coded F20 + then subtypes of disorder further categorised such as F20.1 Hebephrenic Schizophrenia, F20.2 Catatonic schizophrenia etc.
• coding used in indexing medical records, makes easier to find people with specific disorders who may be asked to participate in research + allows international community to communicate about disorders more effectively.

Question 7

How do you use the DSM-5?

Answer 7

• Diagnosis made using all available information to clinician. may simply observe behaviours that indicate particular disorder during sessions
  - e.g. a patient is hearing voices and responding to them.
• Most diagnosis based on unstructured clinical interviews. clinician have no specific set of questions to ask but will be guided by information that patient wants to share.
• Also many structured interview schedules available to assess specific symptom types
  - e.g. the Beck Depression Inventory which consists of 21 questions each with 4 possible responses.
• Simple diagnoses can take just one session, but for more complicated cases can take weeks or months so the consistency of symptoms over time can be considered

Question 8

How do you use the ICD?

Answer 8

• clinical interview conducted (likely to be semi-/unstructured). clinician select key words from the interview such as hallucinations or delusions + look at which disorders match these symptoms.
• clinician able to identify type of mental disorder + then ask further questions to patient to determine further sub-types.
  - E.g. first they may identify a psychotic disorder, then narrow it down to schizophrenia, and then to the further sub-type of paranoid

Question 9

EVALUATION

Evaluate one strength of validity

Answer 9

I -There is research evidence showing that the diagnoses can be accurate.
J - Using DSM-5, Kim-Cohen et al (2005) demonstrated concurrent validity of conduct disorder by interviewing children, their mothers, observing anti-social behaviour and conducting teacher questionnaires.
E - This is useful evidence demonstrates that if more than one source agrees with the DSM diagnosis, it is likely that diagnosis is accurate.

Question 10

EVALUATION

Evaluate a weakness of the valdity

Answer 10

I - The findings from classic studies such as Rosenhan 1973 demonstrate that diagnosis can lack validity.
J - Rosenhan (1973) provided evidence that diagnoses were flawed, as staff were unable to tell mentally disordered patients apart from those who were mentally healthy.
E - This lowers the validity of diagnostic tools accurately diagnosing schizophrenia.

However – this study did demonstrate reliability of diagnosis as most of the pseudopatients were given same diagnosis from their limited symptoms.

Question 11

EVALUATION

Evaluate one strength of reliability

Answer 11

I - There evidence to suggest that diagnosis using both DSM V and ICD 10 have impressive levels of agreement between clinicians.
J - Brown (2001), tested reliability of diagnoses of mood disorders + anxiety using DSM IV + found it to be ‘excellent’. Galeazzi et al (2004) found high inter- rater reliability for clinicians using ICD-10 to conduct a joint interview.
E - demonstrates usefulness of reliable diagnoses as it encourages confidence in clinicians making a consistent diagnosis.

Question 12

EVALUATION

Evaluate a weakness of reliability

Answer 12

I - Reassessment scores for some disorders show major variations in diagnosis.
J - In trials of ‘new’ DSM 5, Kupfer found that major depressive disorder and generalised anxiety disorder both had low reliability scores.
E - means for some diagnosis, this could be different each time they visit clinician making diagnosis unreliable.

HOWEVER – Questions over self report nature of information gathered through interviews can lead to social desirablilty bias + may make symptoms sound worse + they lie to achieve more wanted results. People make feel uncomfortable talking to strangers about mental health, may not diagnose symptom