A psychological approach to diagnosis based on the ICD-11 framework

The ground-breaking volume, A Psychological Approach to Diagnosis Using the ICD-11 as a Framework was recently published (2024) by the International Union of Psychological Science and the American Psychological Association. A psychological approach to diagnosis is a conceptually driven, person-oriented, “biopsychosociocultural” formulation that integrates pertinent history, behaviour, symptoms, phenomenology, and functioning. As operationalized in the book, a psychological approach is particularly compatible with using the ICD-11 as the principal classification framework. The book complements, rather than replaces, the World Health Organization’s (2024) Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural and Neurodevelopmental Disorders (https://www.who.int/publications/i/item/9789240077263). The book is written to be responsive to the unique needs of psychological practice, and addresses the questions ‘Why diagnose?’ and ‘Why ICD-11?’ within a comprehensive global system. Chapters focusing on different groupings of disorders articulate the psychological processes underlying that diagnostic area and their implications for assessment and case conceptualization, including regional, linguistic, and cultural context. Authors include global experts in psychological diagnosis for each major grouping of disorders (e.g., Schizophrenia and Other Primary Psychotic Disorders; Depressive Disorders; Anxiety and Fear-Related Disorders; Disorders Due to Substance Use), as well as areas in which the ICD-11 has introduced major innovations in diagnostic classification (e.g., Disorders Specifically Associated with Stress; Disorders Due to Addictive Behaviours; Personality Disorders; Relational Problems and Maltreatment). The fundamentals of a psychological approach to each area are provided, including presentations and symptom patterns, functioning, case formulation, differential diagnoses, developmental course, cultural and other contextual issues, gender issues, assessment, severity considerations, and validity and other key scientific issues. The volume provides systematic and accessible training never before provided as a part of the implementation of previous ICD classifications. It will be of fundamental importance to psychology trainees and practitioners around the world, and substantial interest to members of other disciplines.

Geoffrey M. Reed, PhD

• Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, USA
• Department of Mental Health and Substance Abuse, World Health Organization, Geneva, Switzerland

The World Health Organization’s (2024) Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural and Neurodevelopmental Disorders (CDDR) was developed through a rigorous international and multidisciplinary process, with psychologists in prominent roles. This included an extensive program of global field studies conducted in multiple languages, many via the Global Clinical Practice Network, consisting of more the 19,000 mental health professionals from 163 countries. A major aim in the development of the ICD-11 CDDR and the field studies was to maximize clinical utility and global applicability in order for the diagnostic manual to function well across global regions, countries and languages. The CDDR’s approach is to recognize cultural differences where these are clinically important while maintaining the goal of a common global diagnostic language. The CDDR facilitate early and accurate diagnosis of mental disorders, helping to reduce the still enormous gap between the number of people who need treatment and the number who receive it. Moreover, the CDDR provide pragmatic, actionable material to assist clinicians in their evaluation of patients and reduce bias in clinical decision-making by facilitating diagnostic assessment in a culturally informed manner. The CDDR’s global approach is also reflected in the IUPsyS/APA volume A Psychological Approach to Diagnosis Using the ICD-11 as a Framework. Authors from all global regions are included, including international leaders in the field, with specific attention to perspectives from low- and middle-income countries. the impact of cultural variation on assessment and case conceptualization has been considered, such as the global applicability and open-access availability of recommended measures. There are considerable benefits to psychology and to psychologists of considering regional, linguistic and cultural variations in conceptualization and presentation of mental disorders as a part of the diagnostic system’s foundation.

Andreas Maercker, PhD, MD

• Department of Psychology, University of Zurich

A psychological approach to diagnosis is a conceptually driven, person-oriented formulation that integrates pertinent history, behaviour, symptoms, phenomenology, and functioning. The psychological approach to diagnosis is a unique and scientifically based strategy that is independent of, though often complementary to, other approaches. A diagnostic classification system for mental disorders offers advantages related to reliable and meaningful communication as well as guidance for action. Within this context, the psychological approach uses knowledge of relevant cognitive, emotional, motivational, interpersonal, and other psychological processes in the conceptualization, assessment, and treatment of mental disorders. The psychological approach adopted in the IUPsyS/APA volume A Psychological Approach to Diagnosis Using the ICD-11 as a Framework facilitates intellectual coherence and supports the clinical application of the ICD-11 Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural and Neurodevelopmental Disorders (CDDR). This perspective influences the assessment of symptoms and assignment of a diagnosis; assessment of functioning and impairment; recording of history; communication with patients about their disorder; and selection of outcome and quality criteria and optimal methodologies for the diagnostic and treatment process. Each chapter in the book provides a psychological model for conceptualizing, assessing and intervening with a particular group of disorders, such as Schizophrenia and Other Primary Psychotic Disorders, Disruptive Behaviour and Dissocial Disorders, Disorders Due to Substance Use, Disorders Due to Addictive Behaviours, and Impulse Control Disorders. Embedded within the bio-psycho-socio-cultural framework, the psychological approach can be used beneficially by all professional groups, including psychologists, psychiatrists, social workers, and nurses.

Tahilia J. Rebello, PhD

• Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons and Research Foundation for Mental Hygiene, New York, USA

This presentation describes the specific ways in which the book’s structure and content enhance its efficacy as a training resource for psychologists who will use WHO’s Clinical Descriptions and Diagnostic Requirements (CDDR) in clinical practice. The book opens with two framing chapters that elucidate both the psychological and global approach to diagnosis. These chapters set a strong foundation by providing learners with relevant historical context and the core principles, approaches, and innovations introduced in the ICD-11 that are reinforced throughout the book. This is followed by sixteen chapters that provide an in-depth discussion of all major ICD-11 Mental, Behavioural and Neurodevelopmental Disorder groupings, and three additional areas of relevance including Conditions Related to Sexual Health, Sleep-Wake Disorders, and Relational Problems and Maltreatment. Chapters provide the overarching logic for the grouping, elaborate on the fundamentals of a psychological approach to each diagnostic area and include key content on the presentations and symptom patterns; subtypes and qualifiers; assessment and case formulation; differential diagnoses and co-occurring conditions; developmental course; cultural and other contextual issues; gender issues; validity; and other key scientific issues. The book’s content reinforces, rather than replaces, the diagnostic material presented in the CDDR. Students and clinicians are provided with a comprehensive, elaborated discussion of the diagnostic material. This includes a rationale for newly introduced innovations, scientific and clinical evidence, elaborated examples, and other context and nuance regarding the CDDR to better prepare users to implement the new diagnostic system in clinical practice.