The ICD-11 and Diagnosis and Classification of Mental Disorders in
People with Intellectual Developmental Disorder
Dr Sherva Elizabeth Cooray, Chair of working group
Email: sherva@doctors.org.uk
Dr Kiran Purandare, Consultant Psychiatrist
The ICD is the global health information benchmark in diagnostic classification for
mortality and morbidity statistics for mental disorders as well as other medical
conditions. It is used clinical care and research to define diseases and study disease
patterns, as well as manage health care, monitor outcomes and allocate resources. The
ultimate aim of the WHO in the forthcoming 11th Revision (ICD-11) is to address several
major shortcomings with current classifications of mental disorders with the core goal of
improving clinical utility based on best available evidence. Once populated The Beta
phase of the ICD-11 will provide an opportunity to make comments, propose definitions
of diseases in a structured manner as well as participation in field trials. The WHO
welcomes the active participation of researchers; health information managers, health
care providers, and others interested stakeholders in the classification.
Problems relating to validity and reliability of ICD-10 diagnostic criteria in PWIDD have
been well documented primarily in view of the limitations in cognitive function and
linguistic
skills.
Consequently,
mental
disorders
in
PWIDD
frequently
remain
unrecognised or under reported, potentially depriving them of access to appropriate
treatment and care. The Royal College of Psychiatrists is one of the few stakeholders in
the world that has a Faculty dedicated to the specialty of IDD and will contribute robustly
to this exercise in collaboration with national and international partners.
The ICD-11/
IDD work stream was established in June 2012, by the Faculty of Psychiatry of
Intellectual Disability within this context.
In the Beta version of the ICD-11 Intellectual Developmental Disorders are categorised
under neuro-developmental Disorders which is defined as: “a group of behavioural and
cognitive disorders that involve impaired or aberrant development of cognitive, motor, or
social functions involving remission and relapses. These disorders are manifest from
childhood and have a steady course without major fluctuations...” It deviates from the
ICD-10 in that problem behaviour is removed from the core classification following
strong lobbying since it was perceived as stigmatising. This issue is likely to create
considerable problems for clinicians who are faced with managing PWIDD with significant
behaviour problems in every day practice.
The work stream reports to the Faculty Executive Committee and the Terms of Reference
of include:
a)
Defining problems within the ICD-10 with regards IDD and formulating pragmatic
solutions based on best available evidence to enable a coherent feedback from
the Faculty to the WHO,
b) Active participation in the forthcoming Field trials internationally (collaboration
with key stakeholders such as the World Psychiatric Association and Lower and
Middle Income Countries which was recognised as crucial to the success of the
exercise).
A sub group of the work stream undertook a systematic Review of Literature using
PRISMA guidelines to critically evaluate and clarify the evidence base to date with
regards the validity, reliability, and clinical utility of the current classificatory systems in
diagnosing mental disorders in PWIDD. The protocol was registered with PROSPERO,
Centre for Review and Dissemination, York and the completed review will be submitted
for publication in the near future. There have also been a number of National and
International presentations and workshops on
the ICD-11/ IDD and Mental Disorders
by members of the work stream.
Future Plans:
The work stream is exploring the optimum way forward with regards categorisation
within the ICD-11 of problem behaviours unique to PWIDD from the perspective of
clinical utility. We are currently involved in setting up a framework that would enable us
to coordinate International Field Trials in collaboration with our stakeholders once the
Beta Format is ready.
To build a better classification based on the needs of PWIDD, with improved consistency,
comparability and utility, input from individuals and multiple stakeholders is a “sine qua
non”.
We would hence welcome robust participation and contributions from our
membership to this project that would have wide ranging implications for all our clinical
practice in the foreseeable future.