Making The Distinction Between The Psychological And Neurological Approach

This page discusses the emergence of the terms 'ICD-CFS' and 'ME/CFS'.

It has become more and more important that a clear distinction is made between the two approaches to the name Chronic Fatigue Syndrome - i.e. the psychological approach versus the neurological approach...


People who follow the controversial Wesseley School of thinking, have come to refer to Chronic Fatigue Syndrome as a psychological disorder.

What confuses matters is that the World Health Organisation (WHO) formally classifies CFS as another name by which ME is known. And ME is classified as a neurological disorder in the WHO's International Classification Of Diseases (ICD G93.3).

So clearly there's a confusion here - when someone says 'Chronic Fatigue Syndrome', are they referring to the (proven) neurological illness ... or the controversial Wessely School's psychiatric approach? Because these two approaches describe two groups of different illnesses!

So to avoid confusion, many people now refer to CFS as ICD-CFS, to stress that they are referring to it as a neurological disorder.

ICD-CFS It's worth mentioning at this point, that when we refer to Chronic Fatigue Syndrome ( CFS ) on this web site, we are referring to CFS as a neurological disorder (as classified by the WHO International Classification of Diseases - otherwise known as ICD-CFS ) - and NOT to the Wessely School's psychological approach to CFS.

You can read more about WHO's definitions of Myalgic Encephalomyelitis (M.E.), Chronic Fatigue Syndrome (ICD-CFS), Post Viral Fatigue Syndrome (PVFS), and Fatigue Syndrome, here...

For more about why ME/CFS is a real, physical, biological illness, click here..

The Importance Of Emphasizing Exercise Intolerance

Still, many feel that ICD-CFS is not an adequate name.


Because by definition (CDC), it is not required that a sufferer experiences exercise intolerance in order to be diagnosed with 'Chronic Fatigue Syndrome'. And it is exercise intolerance that largely (but not solely) distinguishes this illness from other illnesses (both medical and psychiatric), in which fatigue is a prominent symptom.

OK so, why not use the term M.E. then? By definition, a diagnosis of M.E. requires that a sufferer does not tolerate exercise. This is part of what makes it distinctly different to other medical and psychiatric illnesses…

So surely we can just all go back to using the name M.E., right?

Urm… no…

The Problem: If You Don't Have An Inflammation Or Infection Of The Brain, You Don't Have 'Real' M.E.

So why not use the name M.E. instead?

Well, it's because many people are not satisfied with the actual name, Myalgic Encephalomyelitis (M.E. ) - or more specifically, its ending, -myelitis.

What??? ICD-CFS, M.E.

OK, hang on, let me explain…

The suffix -myelitis means 'an inflammation or infection of the brain and spinal cord'. But scientists say that this is not always present in all sufferers. So this is why people think it is incorrect to include -myelitis in the name.

But hang on...

Scientists say that '-myelitis' is not always present in all sufferers... of what? Let's not forget what exactly we're talking about here...

You see, it seems that this illness is made up of subgroups of illnesses (some unknown). In other words, it's an 'umbrella' illness which can be sub-divided into further similar, but different illnesses. And it is generally agreed that M.E. is one of those subgroups.

Now, don't get me wrong - there is proof that an inflammation or infection of the brain exists in M.E. ; it does come up in 'true M.E. sufferers' if more advanced tests are run [ref 24]. But the problem is that it does not appear in all sufferers of this 'umbrella' illness …

... or to put it another way, the inflammation/infection doesn't necessarily occur in the other subgroups of this complex 'umbrella' illness.

People argue that this 'discrepancy' could well have contributed to the medical scepticism that exists today - doctors run basic tests for an inflammation or infection of the brain, and more often than not, don't find anything.

So it's for this reason that when it comes to finding a suitable term for the 'umbrella' illness, the name Myalgic Encephalomyelitis is not suitable because not everyone seems to experience the -myelitis part.

So what are people going to call this 'umbrella' illness (or group of illnesses) until a suitable name can be agreed upon?

The answer: ME/CFS

A Compromise: The Term ME/CFS

There seems to have been a general compromise worldwide to use the term ME/CFS until a more suitable name can be found.

This, it is hoped, will make it clearer that the illness being referred to, is ICD-CFS - a real, physical, neurological disorder. But also makes it clear that the illness being referred to does not necessarily include an inflammation or infection of the brain.

For more about why ME/CFS is a real, physical, biological illness, click here…

Category: ICD-CFS, M.E., ME/CFS

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