The field testing of the ICD-10 multiaxial system was organized as a WHO-coordinated project comprising two international field trials of the applicability, feasibility and reliability of the proposed ICD-10 schema. The specific objectives of the first field trial were: (i) to assess the applicability and ease of use of the ICD-10 multiaxial schema in the daily work of psychiatrists and other mental health professionals; (ii) to determine the perceived usefulness of the multiaxial presentation of ICD-10 for: (a) support of decisions regarding regular patient care; (b) training of mental health professionals; (c) research on mental disorders; and (d) statistical reporting and other public health purposes; (iii) to identify problems experienced in the use of the ICD-10 multiaxial schema; (iv) to obtain an estimate of the inter-rater reliability for each of the axes of the ICD-10 multiaxial schema. The second field trial was aimed at exploring the consequences of the amendments made to the ICD-10 multiaxial system after the analysis of results of the first field test.

The ICD-10 multiaxial field trials package consisted of the following documents: (1) Field Trials Protocol, specifying the phases of work and assessment procedures; (2) Case Study Form, intended for recording the assessment and comments of each clinician for each case; (3) Final Comments Form, intended for clinicians' overall rating of and comments on the ICD-10 multiaxial schema after their completion of the field trial; (4) ICD-10 CDDG, containing detailed descriptions of ICD-10 mental and behavioural disorders as well as a listing of other (i.e., physical) disorders and conditions that were found to be often associated with the disorders included in ICD-10 Chapter V itself; (5) WHO Disability Diagnostic Scale (WHO DDS), with brief guidelines for its use and rating instructions;

The ICD-10 multiaxial system for use in adult psychiatry aims to provide clinicians with a tool for the systematic assessment and a more comprehensive formulation of different aspects of the psychiatric patient's state. The schema was designed after an extensive review of the existing multiaxial systems and developed with the help of an international expert advisory committee and a large number of experts from different parts of the world, including members of the WPA, participants in the development of different versions of the ICD-10 and others collaborating in WHO programmes.

The results of the international field trials of the ICD-10 multiaxial system showed that the majority of clinicians belonging to different psychiatric schools and traditions found the schema to be user-friendly, applicable in their settings and useful in routine clinical work, training, research and statistics of mental disorders. The participants in the first field trial suggested a number of ways to improve the recording of information on specific axes of the ICD-10 multiaxial schema. The recommended amendments were incorporated in the system and tested in the second field trial, the results of which indicated that the suggested changes improved the feasibility and reliability of the schema and its axes. The second field trial also indicated the necessity for further adjustments of the schema, i.e., deletion of the Axis II ‘global functioning’ category and inclusion of brief glossary definitions and descriptions of the Axis I and Axis III categories, which has been done in the current version of the ICD-10 multiaxial system.

The ICD-10 multiaxial assessment is a comprehensive diagnostic procedure intended to provide a biopsychosocial portrayal of the patient's clinical condition. The clinician's evaluation and the multiaxial formulation should be based on all available information about the patient, including: results of the clinical examination (both psychiatric and physical); data obtained from relatives and other informants; review of medical records, laboratory and other diagnostic tests; results of psychological testing; social worker reports; and data from other sources such as school or work reports.

The results of the clinician's multiaxial evaluation of the patient should be recorded on the ICD-10 Multiaxial Diagnostic Formulation Form, which is printed on the inside back cover. This form consists of one section for recording the basic information about the patient, clinician and assessment, and three further sections, each of which is intended for recording and rating information pertinent to specific axes of the ICD-10 multiaxial schema. Prior to the administration of the form, the clinician should decide upon the time period covered by the assessment, that is, current, last month, last year or other (specify) and indicate it on the form.

In the Axis I section of the form, the clinician should list all the positive ICD-10 diagnoses of both mental (including personality) and physical disorders and conditions. The clinician is encouraged to employ as many ICD-10 diagnoses and respective codes as reflect the patient's clinical condition.

ICD-10 Categories of mental and behavioural disorders (F00–F99)

Organic, including symptomatic, mental disorders (F00–F09)

This section comprises a range of mental disorders grouped together on the basis of their having in common a demonstrable etiology in cerebral disease, brain injury, or other insult leading to cerebral dysfunction. The dysfunction may be primary, as in diseases, injuries and insults that affect the brain directly and selectively; or secondary, as in systemic diseases and disorders that attack the brain only as one of the multiple organs or systems of the body that are involved.

Dementia (F00–F03) is a syndrome due to disease of the brain, usually of a chronic or progressive nature, in which there is disturbance of multiple higher cortical functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgement. Consciousness is not clouded. The impairments of cognitive function are commonly accompanied, and occasionally preceded, by deterioration in emotional control, social behaviour, or motivation. This syndrome occurs in Alzheimer's disease, in cerebrovascular disease, and in other conditions primarily or secondarily affecting the brain.

Use additional code, if desired, to identify the underlying disease. The primary code is for the underlying disease and is marked with a dagger (†); an optional additional code for the manifestation is marked with an asterisk (*).

After more than a decade of intensive work, the Tenth Revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) has been finalized and published by the World Health Organization (WHO). It has been produced as a response to recent changes in health service systems in different parts of the world incorporating significant new knowledge that has become available in the past decade. The ICD-10 consists of 21 chapters covering the whole of medical practice. Chapter V of the ICD-10 deals with mental and behavioural disorders and has been produced in several versions, each of which is intended for a particular purpose and aimed at specific users. The main versions of the ICD-10 Classification of Mental and Behavioural Disorders are: Clinical Descriptions and Diagnostic Guidelines (CDDG) – an assembly of detailed specifications of the main clinical features of mental and behavioural disorders intended for general clinical, educational and service use by psychiatrists and other mental health professionals; Diagnostic Criteria for Research (DCR) – a set of specified, operational criteria and rules intended for diagnostic purposes in research on mental and behavioural disorders; Multiaxial Presentations of the ICD-10 – classificatory systems for the assessment of different attributes of the patient's clinical condition, designed for use in adult psychiatry and child and adolescent psychiatry; ICD-10 Primary Health Care Version (ICD-10 PHC) – a simplified list of psychiatric conditions accompanied by guidelines about diagnosis and management for use in primary health care.

Problems related to negative events in childhood and upbringing

Loss of love relationship in childhood

Loss of an emotionally close relationship, such as of a parent, a sibling, a very special friend or a loved pet, by death or permanent departure or rejection.

Removal from home in childhood

Prolonged involuntary stay away from home such as in a foster home, hospital or other institution causing psychosocial distress.

Events resulting in loss of self-esteem in childhood

Events resulting in a negative self-reappraisal by the child such as failure in tasks with high personal investment; disclosure or discovery of a shameful or stigmatizing personal or family event; and other severely humiliating experiences.

Problems related to alleged physical abuse of child

Problems related to incidents in which the child has been injured in the past by any adult in the household to a medically significant extent (e.g., fractures, marked bruising) or that involved excessive forms of violence (e.g., burning or tying up of the child, prolonged starvation, confinement in a small space).

Personal frightening experience in childhood

Experience carrying a threat for the child's future, such as a kidnapping, natural disaster with a threat to life, injury with a threat to self-image or security, or witnessing a severe trauma to a loved one.

Other specified negative life events in childhood

Inadequate parental supervision and control

Lack of parental knowledge of what the child is doing or where the child is; poor control over the child's socially undesirable activities; lack of concern or lack of attempted intervention when the child is in risky or dangerous situations.

The first multiaxial system developed under WHO auspices was a multiaxial classification of mental disorders in childhood. This classification, originally produced as a companion to the ICD-8, currently uses ICD-10 diagnoses and places them in the following multiaxial framework: Axis I – Clinical psychiatric syndromes; Axis II – Specific disorders of psychological development; Axis III – Intellectual level; Axis IV – Medical conditions; Axis V – Associated abnormal psychosocial situations; and Axis VI – Global assessment of psychosocial disability.

Another multiaxial system produced and tested in the framework of a WHO study in primary care settings is a triaxial classification of problems frequently presenting in primary health care. The system was developed to facilitate and stimulate the recording of psychosocial problems in primary health care and requires that general practitioners record for each patient: (a) psychological problem(s); (b) social problem(s); (c) physical problem(s). The fact that the system was not linked to the main body of the ICD–10 made its use sporadic and less attractive.

Since a WHO meeting on the diagnosis and classification of mental disorders held in Moscow in 1969, there has been a number of recommendations regarding the development of a multiaxial classification of mental disorders in old age. The axes were to serve for the recording of the clinical psychiatric syndrome, of the type of (cognitive) impairment and of the severity of the patient's condition in general (i.e., dependence on others for survival).

List of categories

No psychiatric disorder

(Code XX when there is no psychiatric disorder of any type falling within Axis One categories. Depending on the computer system used, operators may opt to key in blanks when XX is coded.)

Pervasive developmental disorders

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

1. F90 Hyperkinetic disorders

2. F91 Conduct disorders

3. F92 Mixed disorders of conduct and emotions

4. F93 Emotional disorders with onset specific to childhood

5. F94 Disorders of social functioning with onset specific to childhood and adolescence

6. F95 Tic disorders

7. F98 Other behavioural and emotional disorders with onset usually occurring in childhood and adolescence

Organic, including symptomatic, mental disorders

1. F00 Dementia in Alzheimer's disease

2. F01 Vascular dementia

3. F02 Dementia in other diseases classified elsewhere

4. F03 Dementia unspecified

5. F04 Organic amnesic syndrome, other than induced by alcohol or other psychoactive substances

6. F05 Delirium, other than induced by alcohol and other psychoactive substances

7. F06 Other mental disorders due to brain damage or dysfunction or to physical disease

8. F07 Personality and behavioural disorders due to brain disease, damage or dysfunction

9. F09 Unspecified organic or symptomatic mental disorder

Mental and behavioural disorders due to psychoactive substance use

1. F10 Mental and behavioural disorders due to use of alcohol

2. F11 Mental and behavioural disorders due to use of opioids

3. F12 Mental and behavioural disorders due to use of cannabinoids

4. F13 Mental and behavioural disorders due to use of sedatives or hypnotics

5. F14 Mental and behavioural disorders due to use of cocaine

6. F15 Mental and behavioural disorders due to use of other stimulants, including caffeine

7. […]

Intellectual level within the normal range

Mental retardation

Overview of this block

1. F70 Mild mental retardation

2. F71 Moderate mental retardation

3. F72 Severe mental retardation

4. F73 Profound mental retardation

5. F78 Other mental retardation

6. F79 Unspecified mental retardation

A fourth character may be used to specify the extent of associated behavioural impairment:

1. F7x.0 No, or minimal, impairment of behaviour

2. F7x.1 Significant impairment of behaviour requiring attention or treatment

3. F7x.8 Other impairments of behaviour

4. F7x.9 Without mention of impairment of behaviour

Introduction

Mental retardation is a condition of arrested or incomplete development of the mind, which is especially characterized by impairment of skills manifested during the developmental period, which contribute to the overall level of intelligence, i.e. cognitive, language, motor, and social abilities. Retardation can occur with or without any other mental or physical disorder. However, mentally retarded individuals can experience the full range of mental disorders, and the prevalence of other mental disorders is at least three to four times greater in this population than in the general population. In addition, mentally retarded individuals are at greater risk of exploitation and physical/sexual abuse. Adaptive behaviour is always impaired, but in protected social environments where support is available this impairment may not be at all obvious in subjects with mild mental retardation.

A fourth character may be used to specify the extent of the behavioural impairment, if this is not due to an associated disorder:

1. F7x.0 No, or minimal, impairment of behaviour

2. F7x.1 Significant impairment of behaviour requiring attention or treatment

3. F7x.8 Other impairments of behaviour

4. F7x.9 Without mention of impairment of behaviour