Mental Health Classification

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Mental Health Classification

The Gods have made thee mad. (Homer, Odyssey, 8th C, BC)

We are all born mad. Some remain so. (Samuel Beckett, Waiting for Godot, 1960)

The classification of mental disorders is essentially the holy grail of psychiatry. Creating a parsimonious, efficient and universal classification system is something that has only in the last five decades really begun to take shape. Pushed by the de-institutionalization movement the International Classification of Diseases (ICD) produced by the World Health Organization (WHO) and the Diagnostic and Statistical Manual of Mental Disorders produced by the American Psychiatric Association (APA), were the first comprehensive systems. Both list categories of disorders thought to be distinct types, and have deliberately converged their codes in recent revisions so that the manuals are often broadly comparable, although significant differences remain.

The ICD is an international standard diagnostic classification for a wide variety of health conditions. One chapter focuses on ’mental and behavioural disorders’ and consists of ten main (plus one supplementary) categories:

1 Organic, including symptomatic, mental disorders.

2 Mental and behavioural disorders due to use of psychoactive substances.

3 Schizophrenia, schizotypal and delusional disorders.

4 Mood [affective] disorders.

5 Neurotic, stress-related and somatoform disorders.

6 Behavioural syndromes associated with physiological disturbances and physical factors.

7 Disorders of personality and behaviour in adult persons.

8 Mental retardation.

9 Disorders of psychological development.

10 Behavioural and emotional disorders with onset usually occurring in childhood and adolescence.

11 In addition, a group of ’unspecified mental disorders’.

The DSM-IV-TR (APA, 2000) consists of five axes (domains) on which disorder can be assessed. The five axes are:

Axis I: Clinical Disorders (all mental disorders except Personality Disorders and Mental Retardation).

Axis II: Personality Disorders and Mental Retardation.

Axis III: General Medical Conditions (must be connected to a Mental Disorder).

Axis IV: Psychosocial and Environmental Problems (for example limited social support network).

Axis V: Global Assessment of Functioning (Psychological, social and job-related functions are evaluated on a continuum between mental health and extreme mental disorder).

When the Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) was released at the American Psychiatric Association’s Annual Meeting in May 2013, it marked the end of more than a decade’s journey in revising the criteria for the diagnosis and classification of mental disorders. DSM-V serves as the universal authority for the diagnosis of psychiatric disorders and most diagnosis and treatment of mental illness is based on the criteria and guidance set out in the manual. The publication of a revised and significantly altered version therefore has significant practical implications.

The manual is divided into three major sections:

1 Introduction and clear information on how to use the DSM.

2 Provides information and categorical diagnoses.

3 Provides self-assessment tools, as well as categories that require more research.

While DSM-V has approximately the same number of conditions as DSM-IV there have been some significant changes in specific disorders. A summary of these is as follows:

Autism — There is now a single condition called autism spectrum disorder, which incorporates four previous separate disorders including autistic disorder (autism), Asperger’s disorder, childhood disintegrative disorder and pervasive developmental disorder not otherwise specified.

Disruptive Mood — Dysregulation Disorder Childhood bipolar disorder has a new name — ’intended to address issues of over-diagnosis and over-treatment of bipolar disorder in children’. This can be diagnosed in children up to age 18 who exhibit persistent irritability and frequent episodes of extreme behavioural dyscontrol (e.g., they are out of control).

ADHD — Attention deficit hyperactivity disorder (ADHD) has been modified especially to emphasize that this disorder can continue into adulthood. The one ’big’ change is that you can be diagnosed with ADHD as an adult if you meet one less symptom than if you are a child.

Bereavement Exclusion Removal — In the DSM-IV, if you were grieving the loss of a loved one, technically you couldn’t be diagnosed with major depression disorder in the first two months of your grief. This exclusion was removed in the DSM-V for a number of reasons: the implication that bereavement typically lasts only two months; bereavement is recognized as a severe psychosocial stressor that can precipitate a major depressive episode; bereavement-related major depression is most likely to occur in individuals with past personal and family histories of major depressive episodes; the depressive symptoms associated with bereavement-related depression respond to the same psychosocial and medication treatments as non-bereavement-related depression.

Post-Traumatic Stress Disorder (PTSD) — More attention is now paid to behavioural symptoms that accompany PTSD in the DSM-V. It now includes four primary major symptom clusters: re-experiencing, arousal, avoidance and persistent negative alterations in cognitions and mood. The condition is now developmentally more sensitive in that diagnostic thresholds have been lowered for children and adolescents.

Major and Mild Neurocognitive Disorder — Major Neurocognitive Disorder now subsumes dementia and the amnestic disorder. But a new disorder, Mild Neurocognitive Disorder, was also added.

Other New & Notable Disorders. Both Binge Eating Disorder and Premenstrual Dysphoric Disorder are now official diagnoses in the DSM-V (they were not prior to this, although still commonly diagnosed by clinicians). Hoarding disorder is also now recognized as a real disorder, separate from OCD, ’which reflects persistent difficulty discarding or parting with possessions due to a perceived need to save the items and distress associated with discarding them. Hoarding disorder may have unique neurobiological correlates, is associated with significant impairment, and may respond to clinical intervention.’

These criticisms are not new and certainly not unique to DSM-V. Is the reliability of diagnosis improved? That is, do psychiatrists and psychologists agree upon diagnoses? Is all this medicalization in the real interests of big pharmaceutical companies?

There is also the serious issue of culture bias. It is argued that national culture affects the experience, expression, generation and management of symptoms. It also affects the management of symptoms. People in different cultures use different words and idioms to express their psychological distress and pain. It also reflects shame in different ways. Many cultures accept supernatural explanations for mental illness while others try hard to medicalize it as soon as possible. What place does a universal diagnostic manual have in a multi-cultural and diverse world? And does it help to improve the mental health literacy of the general public?


American Psychiatric Association. 1987. Diagnostic and Statistical Manual of Mental Disorders (3th edition., text rev.). Washington, DC.

American Psychiatric Association. 2013. Diagnostic and Statistical Manual of Mental Disorders (5th edition.). Washington, DC.