This document provides an overview of psychiatric classification and diagnosis. It discusses the aims of classification, including facilitating communication between clinicians and standardizing diagnoses. The two main classification systems, ICD-10 and DSM-5, are described. ICD-10 was developed by the WHO and is used globally, while DSM-5 was developed by the APA and is used primarily in the US. The document outlines the history of psychiatric classification and compares features of ICD-10 and DSM-5.

1. Classification and Diagnosis in
Psychiatry
Diagnostic criteria – ICD 10, DSM 5
Dr Dalal Naeem
Contact Email: naeemmidalal@gmail.com

2. Outline • Aim of this lecture
• Learning objectives
• Background
• Definition of the term-Classification
• Units of Classification
• The fundamental purpose of diagnosis and classification
• Other purposes of diagnosis and classification
• History of classification in psychiatry
• The two most important current psychiatric classifications
• International Classification of Diseases ( ICD )
• Diagnostic and Statistical Manual of Mental Disorders(DSM)

3. Aim of Lecture
• To familiarise with the international diagnostic criteria:
DSM-5 and ICD-10

4. Learning Objectives
• Understand the principles and reasoning behind classification in medicine
and psychiatry.
• Be able to state the importance of classifying mental disorder
• Be able to describe the recent history of psychiatric classification.
• Be able to compare DSM and ICD classifications of mental disorder

5. What is psychiatry?
• Brain Health
• Function of the mind
• An understanding of functional neuroanatomy is very important to a
practicing health care worker because psychiatric conditions generally
result from a disturbance in the functional and structural anatomy of
the nervous system.
• When a patient presents with a psychiatric condition, the clinician
should have an idea of the part of the brain affected.

6. Bio - Psycho - Social
The bio-psycho-social model of health and illness is a framework developed by George L. Engel that states that
interactions between biological, psychological, and social factors determine the cause, manifestation, and outcome of
wellness and disease.
BIO
Gender, physical illness,
disability, genetics, Immune function,
stress reactivity, neurochemistry…
Illness
PSYCHO
Learning memory, attitude, beliefs,
personality, coping skills, past trauma,
emotions, behavior….
SOCIAL
Social support, family background,
socioeconomic status, culture, traditions,
religious norms, education.
Illness
Social
Psychology
Biology
Naeem Dalal, MD
Naeem Dalal, MD

7. Biopsychosocial model of illness.
A holistic approach to addressing health involves a treatment model known as the biopsychosocial
(BPS) approach of management. The BSP uses a person centered view of illness, rather than
simply a disease centered one [3]
Health is more than the lack of sicknesses. World Health Organization (WHO) defines health as: “A
state of complete physical, mental and social well-being and not merely the absence of disease or
disability.”
• Recurrent chronic stress or traumatic stress is a risk to developing mental illness.
• For example, COVID 19 pandemic = Stress
• Acute and chronic stress directly affects brain health
• Disrupts neuroplasticity which may predispose to mental health illness.
BIO
Gender, physical illness,
disability, genetics, Immune function,
stress reactivity, neurochemistry…
Illness
PSYCHO
Learning memory, attitude, beliefs,
personality, coping skills, past trauma,
emotions, behavior….
SOCIAL
Social support, family background,
socioeconomic status, culture, traditions,
religious norms, education.
Naeem Dalal, MD

8. Background
• Most physical conditions are classified on the basis of aetiology,e.g Viral
Pneumonia, Bacterial Pneumonia, Viral Hepatitis.
OR
• On the basis of Structural Pathology,e.g.Bronchopneumonia
OR
• Based on Symptoms,e.g. Migraine Headache, Tension Headache, Cluster
Headache
• Psychiatric disorders are diagnosed based mainly on symptoms.
Few are based on aetiology e.g. Alzheimer’s disease and Down syndrome

9. Classification
“Activity of ordering or arrangement of objects
into groups or sets on the basis of their
relationships.”
Sokal R.R.(1974) Science, 185:115-123

10. Classification
“Procedure for constructing groups or categories and for
assigning entities (disorders or persons) to these
categories on the basis of their shared attributes or
relations”
Millon T.( ) y , 1991) J. Abnorm.Psychol., 100:245-261

11. Units of Classifications
Disorders?
• In medicine, a disorder is a functional abnormality or disturbance.
• Medical disorders can be categorized into mental disorders, physical
disorders, genetic disorders, metabolic disorders, emotional and
behavioural disorders, and functional disorders.
• In mental health, the term mental disorder is used as a way of
acknowledging the complex interaction of biological, social, and
psychological factors in psychiatric conditions.

12. Disease?
• The term disease broadly refers to any condition that impairs the normal
functioning of the body.
• Commonly, the term disease is used to refer specifically to infectious
diseases, which are clinically evident diseases that result from the
presence of pathogenic microbial agents, including viruses, bacteria,
fungi, protozoa, multicellular organisms, and aberrant proteins known as
prions.
• Non-infectious diseases are all other diseases, including most forms of
cancer, heart disease, and genetic disease.
• Normally four main types of diseases are considered: pathogenic
diseases, deficiency diseases, hereditary diseases, and physiological
diseases.

13. Syndrome?
• A syndrome is the association of several medical signs, symptoms,
and or other characteristics that often occur together.
• Some syndromes, such as Down syndrome, have only one cause;
others, such as Parkinsonian syndrome, have multiple possible
causes. In other cases, the cause of the syndrome is unknown.

14. In Psychiatry
• Most of the disorders or diseases diagnosed are syndromes
Syndroma
• Collections of symptoms that tend to appear together and that seem
to have a characteristic course and outcome

15. The fundamental purpose of diagnosis and classification
• Help to simplify our thinking and reduce the complexity of clinical phenomena to
a generally/internationally accepted diagnosis.
• Facilitate communication between clinicians (concisely summarizes information
for all other clinicians)and other allied professionals
• Distinguish one psychiatric diagnosis from another, so that clinicians can offer the
most appropriate and effective treatment
• Helps make generalizations in treatment response, course and prognosis of
individual patients.
• Help to predict the outcome of the disorder
• Creates a framework for research in psychiatry which then assists in the search
for pathophysiology and aetiology

16. Other purposes of diagnosis and classification
Diagnoses are used:
• To monitor treatment
• To make decisions about insurance coverage
• By attorneys in malpractice suits and in litigation
• By health care epidemiologists to determine the incidence and
prevalence of various diseases throughout the world.

17. History of classification in psychiatry
• The various classification systems used in psychiatry date back to Hippocrates, who
introduced the terms mania and hysteria as forms of mental illness in the fifth century
BC.
• Since then, each era has introduced its own psychiatric classification.
• The first US classification was introduced in 1869 at the annual meeting of the American
Medico-Psychological Association, which later became the American Psychiatric
Association.
• In 1952, the American Psychiatric Association’s Committee on Nomenclature and
Statistics published the first edition of DSM (DSM-I). Six editions have been published
since then with the latest being DSM-5 in 2013
• DSM-II (1968); DSM-III (1980); a revised DSM-III, DSM-III-R (1987); DSM-IV (1994);DSM-
IV-TR (TR stands for Text Revision) (2000); and DSM-5 published in 2013

18. The two most important current psychiatric classifications
• DSM-5 (Diagnostic and Statistical Manual of the American Psychiatric
Association, Fifth Edition, 2013)
• ICD-10 (International Statistical Classification of Diseases and Related Health
Problems, Tenth Edition, 1992)
• All categories used in DSM-5 are found in ICD-10,but not all ICD-10 categories
are in DSM-5.

19. International Classification of Diseases ( ICD )
• Developed by the World Health Organization
• Used in Europe, Africa and Asia and South America
• Comprehensive classification of all “diseases and related health
problems”
• Basis of obligatory report to WHO on morbidity data

20. International Statistical Classification of Diseases and Related Health Problems 10th
Revision (ICD-10)-WHO Version for ;2016
• This is a shortened version of the fifth chapter of the ICD-10: Mental and behavioural disorders. It covers
ICD codes F00 to F99.
• The chapter contains the International Classification of Mental and Behavioural Disorders. All versions of
the ICD-10, including the most recent one (2016), can be browsed freely on the website of the World
Health Organisation(WHO).
• It can also be downloaded in PDF format ( https://apps.who.int/iris/handle/10665/246208)

21. Diagnostic and Statistical Manual of Mental Disorders(DSM)
• Developed by the American Psychiatric Association
• Is the official psychiatric coding system used in the United States and
for research purposes worldwide

22. DSM-5 CLASSIFICATION
• The DSM-5 lists 22 major categories of mental disorders, comprising more
than 150 discrete illnesses.
• Each disorder listed in DSM-5 is described in detail under the following
headings:
Epidemiology
Aetiology
Diagnosis
Differential diagnoses
Clinical features
treatment of the disorder

23. The Organization of DSM-5
• Neurodevelopmental Disorders
• Schizophrenia Spectrum and Other Psychotic
Disorders
• Bipolar and Related Disorders
• Depressive Disorders
• Anxiety Disorders
• Obsessive-Compulsive and Related Disorders
• Trauma- and Stressor-Related Disorders
• Dissociative Disorders
• Somatic Symptom Disorders
• Feeding and Eating Disorders
• Elimination Disorders
• Sleep-Wake Disorders
• Sexual Dysfunctions
• Gender Dysphoria
• Disruptive, Impulse Control and
Conduct Disorders
• Substance Use and Addictive Disorders
• Neurocognitive Disorders
• Personality Disorders
• Paraphilic Disorders
• Other Disorders
www.psychiatry.org

24. Diagnostic criteria
• A list of features that must be present for the diagnosis to be made
• Such criteria increase the reliability of the process of diagnosis.

25. Differences between ICD and DSM
ICD
• Official world classification
• Intended for use by all health
practitioners
• Special attention given to primary care
and low- and middle-income countries.
• Major focus on clinical utility (planned
for ICD-11) with reduction of number of
diagnoses
• Provides diagnostic descriptions and
guidance but does not employ
operational criteria
DSM
• US classification (but used in many
other countries)
• Used primarily by psychiatrists
• Focused mainly on secondary
psychiatric care in high-income
countries
• Tends to increase the number of
diagnoses with each succeeding
revision
• Diagnostic system depends on
operational criteria using a polythetic
system for most conditions (i.e.
combination of criteria that need not all
be the same)

26. References:
• Acknowledgement: Dr Brain Maila slides curtsey of Mrs J Ncheka
• A comparison of DSM and ICD classifications of mental disorder: https://www.Cambridge.Org/core/journals/advances-in-psychiatric-
treatment/article/comparison-of-dsm-and-icd-classifications-of-mental-disorder/625C40990677716E8C92AF0A6374F896
• ICD VS DSM - KEY DIFFERENCES AND SIMILARITIES: https://www.Flatworldsolutions.Com/healthcare/articles/icd-vs-dsm-key-
differences-and-similarities.Php
• https://www.verywellmind.com/what-is-a-crisis-2795061 Kendra Cherry
• https://www.dshs.wa.gov/book/export/html/490
• Psychological First Aid PFA Guide for Field Workers (WHO, WTF and WVI, 2011), in multiple languages https://bit.ly/2VeJUX7
• Doing What Matters in Times of Stress: An Illustrated Guide (WHO) https://bit.ly/3aJSdib
• Community-Based Psychological First Aid, A Practical Guide to Helping Individuals and Communities During Difficult Times by Gerard
A
Jacobs https://amzn.to/2MwHOwD
• The Johns Hopkins Guide to Psychological First Aid 1st Edition by George S. Everly Jr, Jeffrey M. Lating. https://amzn.to/3eSAK9J
• Psychological Basis of Psychiatry by M.S. Thambirajah, https://amzn.to/2XyA97j
• https://twitter.com/VectorSting
• Emily A Holmes et el, 15th April, 2020, Multidisciplinary research priorities for the COVID-19 pandemic: a call for action for mental
health science , April 15, 2020 S2215-0366(20)30168-1 Lancet Psychiatry 2020
• https://www.who.int/news-room/fact-sheets/detail/mental-health-in-emergencies