Mental condition and disorder classification systems

Underlying principles of classification

Diagnosis of mental conditions can lead to effective and efficient treatment and, ideally, cure. However, one must be careful not to use labels of classification as the basis for discrimination or prejudice. In some cases, mental conditions may be context or culture-specific (such as the Paris Syndrome for Japanese tourists). There are two main systems of mental condition classification: the categorical approach and the dimensional approach.

Categorical approach

The categorical approach uses discrete, distinct categories and sub-categories to order mental conditions and disorders. The categorical approach is very much ‘all or nothing’; that is, you either suffer from a particular mental illness or you don’t, and there are no varying degrees.

The categorical approach utilises two tools to aid in diagnosis: the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Edition 4 (although the current edition is Edition 5)) and the ICD-10 (International Classification of Diseases and Related Health Problems, Edition 10).

DSM-IV and ICD-10

The DSM-IV and ICD-10 are similar. Both:

  • Classify mental disorders and order them categorically
  • Adopt a distinct ‘all or nothing’ approach
  • Use recognisable symptoms to aid their classifcation

However, the two manuals have a few differences:

  • The DSM-IV is most commonly used in Australia and the United States of America, whereas Europe tends to use the ICD-10
  • The DSM-IV uses 16 categories, whereas the ICD-10 uses 21 chapters
  • The ICD-10 is used by doctors and psychiatrists

The DSM-IV uses five axis:

  • Axis 1: Clinical disorders and other conditions
  • Axis 2: Personality disorders and mental retardation
  • Axis 3: General medical conditions
  • Axis 4: Psychosocial and environmental problems
  • Axis 5: Global assessment of functioning

Strengths and weaknesses

In general, the categorical approach has numerous strengths and advantageous points:

  • It uses a systematic approach to classification, outlining symptoms
  • It is based on scientific research
  • It is consistent and comprehensive

However, it also comes with some limitations:

  • As it uses an ‘all or nothing’ approach, it may be devisive; stigmatism and labeling may be the product
  • It does not cater for unique combinations of more than one condition
  • It disallows a dimensional, partial outlook to mental conditions

Dimensional approach

The dimensional approach takes a very different outlook to the categorical approach. Unlike the categorical approach, it uses scales and continuums to diagnose conditions, quantifying symptoms so that they can be analysed.

Strengths and weaknesses

Strengths of the dimensional approach are:

  • It allows for unique combinations of mental conditions
  • It tends to avoid labeling and stigmatism as it does not distinctly divide people into groups
  • It may result in a more comprehensive diagnosis

Limitations of the dimensional approach are:

  • It can scarcely be applied to the DSM-IV or the ICD-10
  • Due to unique combinations being taken into account, the diagnosis process can become very time-consuming
  • There are potentially endless combinations, meaning that accurate diagnosis may prove difficult