Evaluation: DSM and ICD and Diagnosis

Evaluation: DSM and ICD and Diagnosis

1. DSM-IV/DSM-IV-TR

   • The DSM stands for the Diagnostic and Statistical Manual of mental disorders and only focuses on diagnosis of mental health disorders.
   • The DSM is only in English and is limited to certain countries - inaccessible to the whole world.
   • Its diagnoses are based one symptoms as well as existing medical issues and environmental stressors.
   • The DSM is revised regularly and is currently on its fifth edition.
   • The mental health disorders are put on 5 axes, which include psychiatric diagnoses, personality problems, general medical conditions, environmental stress and 'global functioning'.

2. ICD-10

   • The ICD stands for the International Classification of Disorders. It focuses on all health conditions, including mental health.
   • The ICD is multi-lingual and aims to improve healthcare and diagnosis all over the world.
   • The ICD is in its 10 edition and is reviewed regularly.
   • Its diagnoses are based on symptoms only.
   • Section F of the ICD is specific for mental health disorders and within this section, each disorder is grouped in a family. For example, depression is part of the the mood disorders (represented by the family digit 3). More digits can be added to this to represent the specific disorder, the sub-type of the disorder, and very specific categorisations.

3. Reliability

   • Reliability refers to whether diagnosis is consistent regardless of clinician.
     • One issue with reliability of diagnosis is the subjectivity of criteria. This is because one clinician may believe a behaviour meets a certain criteria whereas another may not.
   • Inter-rater reliability is when two or more clinicians use the same diagnostic tool and come to the same diagnosis for the same individual.
     • Rosenhan found that the DSM-II had high inter-rater reliability as 7/8 pseudo patients in the study (with the same symptoms) were all diagnosed with schizophrenia by different clinicians using the DSM-II.
       • Goldstein found that the DSM-III also had high inter-rater reliability, and Brown found the DSM-IV had high inter-rater reliability.
   • Test-retest reliability is when the same diagnosis is reached with the same diagnostic tool but after a period of time to see if the diagnosis is consistent.
     • Pontinovsky found the ICD had good test re-test reliability.
       • Sanchez-Villegas found the DSM-IV-TR also has high test re-test reliability.

4. Validity

   • Validity refers to if the diagnosis is correct, reflects the actual disorder and can lead to a suitable treatment that works.
   • Validity can be affected by many factors, such as comorbidity (when symptoms overlap and can be applied to multiple disorders) which leads to a higher chance of misdiagnosis, implicit bias of the clinician (when a clinician's prejudices against people may influence their diagnosis), patient factors like accent which could lead to a misinterpretation of information, and revisions of systems which can improve the validity of diagnostic systems.
   • Construct validity refers to how far the constructs that are being measured represents that disorder.
     • Brown et al found that the DSM-IV had low construct validity.
       • However, Stinchfield found that the DSM-IV had high construct validity.
   • Concurrent validity is when two tests done at the same time come up with the same diagnosis, which would suggest the tests measure what they seem to measure.
     • Hoffman and Lee found that DSM criteria had high concurrent validity with other diagnostic tools such as interviews and questionnaires.