One of the basic problems with treatment of ME is the original diagnosis of the illness.
Invariably it is too late and the current environment in the UK means that diagnosis may cover a broad range of illnesses with similar symptoms which are brought together under one diagnosis - ME - a dead-end of a medical diagnosis by a medical community which cannot even agree on a name.

In order to establish correct and early diagnosis there needs to be a standard clinical diagnosis method used throughout the country. This area is currently clouded with up to four sets of diagnostic criteria being available for use.

Guidelines - what they are

When a doctor or paediatrician gives a diagnosis of myalgic encephalomyelitis then they do this currently by exclusion of other illnesses and by means of basic blood tests.

Diagnostic guidelines are meant to be a means to assist in diagnosis. 

Another important distinction is between guidelines used for research and those used for clinical diagnosis. One may think these would always be the same.

Why they are important

If a diagnosis is given to a patient based on a different interpretation of an illness then the diagnosis may be flawed. In an illness such as ME, where it is obvious that politics and prejudice have already affected how research is funded in the UK, using flawed diagnostic criteria or even using different criteria means that it will be even harder to establish a proper baseline for treatment/cure.

Here are the more common guidelines which you may come across. To read more on these we have added some links where the discussion on the merits, or otherwise, of these criteria are discussed more fully.

London Criteria

A set of criteria apparently still used by the Medical Research Council in assisting their determination of funding for ME-related projects (all psychiatric).

The criticisms of these criteria include the fact that they have never been published and therefore cannot be used objectively to select patients for a study. The MRC still find it necessary to use these criteria in conducting the PACE trials to study psychiatric paradigms for treatment of ME sufferers - something which most of the people in the ME community who have studied this find negligent.

Oxford Criteria

A set of criteria created by and for psychiatrists - these criteria are far less rigorous and may include patients with fatigue as their only symptom. As such it allows far too many possibilities of inclusion of non-ME patients and serves no useful purpose, other than to aid the assertions of psychiatric groups who see ME as a somatoform disorder. In our opinion they, therefore, serve no real useful or scientific purpose.


The RCPH Guidelines

A set of guidelines we feel disappointed with. These are oriented toward the psychiatric/psychologist viewpoint with lots of references to papers by persons prominent in the debate promoting the viewpoint of ME being a psychological illness. The sad fact is that paediatricians in this country are guided by these guidelines.

Fukuda (USA Centres for Disease Control and Prevention)

These are a revised version of earlier guidelines by the ISA CDCP.

See also -


South Australian Criteria

Similar to the Canadian guidelines (see below) - the newest guidelines from Australia, for GPs.

Canadian Criteria

Proper, up-to-date clinical guidelines which can also be used as a base for research criteria. Findings from the study by Leonard A. Jason PhD (Comparing the Fukuda et al. Criteria and the Canadian Case Definition for Chronic Fatigue Syndrome) indicated that the Canadian criteria captured many of the cardiopulmonary and neurological abnormalities, which were not currently assessed by the Fukuda criteria. The Canadian criteria also selected cases with 'less psychiatric co-morbidity, more physical functional impairment, and more fatigue/weakness, neuropsychiatric, and neurological symptoms' and individuals selected by these criteria were significantly different from psychiatric controls with CFS.


A link to a full description of the Canadian Guidelines is held in the Library - click here.

A recent addition to the documentation has been an overview document which can be viewed via this link.

Myalgic Encephalomyelitis: International Consensus Criteria 2011

The Canadian Guidelines have been used as a base for a new set of guidelines published in 2011.


and click here


Order Bound Copies of the Canadian Guidelines
Invest in ME are now responsible for distribution of the bound copies of the Canadian Guidelines within the UK. If you or your group would like to order copies please email us at this address with title Canadian Guidelines.


IIME Position

Currently, the best hope to establish a common, workable set of guidelines is to adopt the Canadian Guidelines. This is one of the objectives of Invest in ME. It is one of the fundamental issues which needs to be resolved in order for myalgic encephalomyelitis to be treated in the correct way.

NHS Scotland - November 2011

NHS Health Scotland has recommended using the Canadian Guidelines for diagnosing ME - click here.

New International Consensus Criteria

A new standard for guidelines has been published by a leading group of international researchers. The authors discuss the clinical application of their criteria, as well as paediatric considerations and research applications. The authors conclude that they -

 “believe the International Consensus Criteria will help clarify the unique signature of ME” and they state unambiguously that “individuals meeting the International Consensus Criteria have myalgic encephalomyelitis and should be removed from the Reeves empirical criteria and the National Institute for (Health and) Clinical Excellence (NICE) criteria for chronic fatigue syndrome”.

Invest in ME IiME are the UK distributors for the current Canadian Guidelines and welcome these guidelines. We have for a long time stated that we support an evolutionary development and improvement of the Canadian Guidelines. We believe this is a step in the right direction.

The ICC can be ordered from IiME - please email the charity for this -

In the past we, together with the European ME Alliance, have discussed with our conference presenters regarding updating of the criteria. The International Consensus Criteria are welcomed and we fully support these new criteria. Available to download via this link - click here.