How to write a good introduction for an ME/CFS paper?

It is my unscientific gut feeling that there is a tradition of writing the introduction sections in the ME field that differs from other fields in unhelpful ways. With few exceptions ME papers start their intro section with a lengthy and detailed description of ME, citing all manner of statistics on prevalence, severity, recovery, female predominance etc - even if they're of no relevance to the study at hand

A quick look at a random range of studies about other conditions like autism, depression, MS, stroke and more found none of them give the same level of unnecessary detail in their intro sections

I suspect the ME tradition stems from a well-intentioned reflex of wanting to educate the wider world about ME, possibly due to some vague sense of having to justify resources being spent on research into ME

Be that as it may, I think it is unhelpful, for a number of reasons

• descriptions of ME are often misleading, typically by focusing above all else on fatigue
• while PEM is at least getting mentioned more frequently these days it, too, is often poorly described in a way that makes it seem to be the same as common forms of exertion intolerance, or else the descriptions contradict each other from one paper to another, e.g. some state PEM lasts at least 14 hours and others say 24 hours
• all the commonly cited statistics on prevalence, severity, recovery, female predominance rest - at best - on inconclusive findings from studies with shortcomings such as highly variable application of diagnostic criteria, selection bias and more

Many of the misleading descriptions and poorly evidenced statistics have become accepted "truth" by sheer dint of repetition. While intro sections may seem to be the least important part of a paper this relentless repetition of received wisdom is still problematic because

• it perpetuates inaccurate ideas about ME in general
• it discourages further and better epidemiological studies that could improve the evidence base
• it nudges researchers to think more about fatigue than about PEM, and to think about both PEM and fatigue as something familiar from other conditions (my impression is this even applies to researchers who do know better at the conscious intellectual level but at the gut level they're still influenced by the relentless repetition of the inaccurate descriptions, and that this impedes out of the box thinking)
• it's confusing, especially for people new to the field, when different papers all state different statistics, sometimes wildly different
• the confusion lends itself to being abused for motivated reasoning, you can find whatever stats you need to conveniently support your point
• descriptions which focus on the severe end of ME can be confusing or appear exaggerated when a study then involves mobile patients
• some descriptions read more like advocacy than science which risks deflecting attention from the actual findings of the study

What's the solution then? Some ideas:

• keep the basic description short and to the point, similar to how introductions are written in other fields, optionally refer to a general review on ME, example:

ME/CFS is a potentially debilitating illness of unknown pathogenesis, no cure and no effective treatments. (optional addition: For a detailed review refer to Xcvb et al 2023)​

• however, I think adding a brief note about PEM is justified even where PEM, beyond diagnostic criteria, is not directly relevant to a study because I think we need a period of highlighting PEM to counteract the insiduous effects the term fatigue has had over the decades, but only go into more detail if PEM is directly relevant to a study, examples:

A hallmark of ME/CFS is Post-Exertional Malaise (PEM), an unusual and highly specific pattern of significant worsening of symptoms after previously easily tolerated mental or physical exertion.
or
A hallmark of ME/CFS is Post-Exertional Malaise (PEM). This refers to a significant worsening of symptoms after previously easily tolerated mental or physical exertion. PEM can be distinguished from other forms of exertion intolerance by its unusual and highly specific pattern of symptom exacerbation. (optional addition: For a detailed review refer to Mlkj et al 2024)​

• avoid making specific claims like 'only 5% recover' or 'PEM lasts a minimum of x hours', i.e. anything where the evidence base is either weak or conflicting unless of course it is directly relevant to the study at hand in which case discuss the uncertainty in the literature

Final question:
What are currently the best general reviews suitable for referencing we have of ME and of PEM?

 

Mostly agree with these points about overly long introductions.

Yes because the general knowledge level about MECFS is much much lower than say MS or Alzheimer’s.

However, I do not favor de-emphasizing the role of fatigue in ME/CFS (or think that it is misleading to focus on fatigue). For me, baseline fatigue and brain fog, not PEM, is what disables me. People with MECFS are sick at rest, not only following exertion. I think a lot of patients would describe their baseline fatigue/lack of energy as disabling.

 

Where I'm coming from is not that fatigue isn't a huge issue - it very clearly is

The issue in the research context is that fatigue is so spectacularly non-specific that the past - and present - hyperfocus on fatigue hasn't been getting us anywhere. That lack of progress alone is a sign it's time to broaden our thinking. We're more likely to find a way in to some relevant mechanisms by concentrating on features more specific to ME

I'm also not not the least worried that fatigue will ever be forgotten about. The idea that ME=fatigue is too deeply ingrained for that. And it's still there in the ME/CFS label as well. Realistically, everyone reading a ME paper comes at it with the preconception ME is about fatigue, there's no need to reinforce this further by writing about it - again again - in the intro section. But we do need to nudge people out of the rut of thinking it's only fatigue and get researchers thinking about new angles that might be more productive

 

ME too, but I do find the term "fatigue" inaccurate and unhelpful as in practice (at least in my moderate and severe states) it's a fundamental lack of function due to an inability to produce sufficient energy in the first place, whereas fatigue continually gets misunderstood just as being unusually tired after activity.

I think making this distinction understood in paper intros would be valuable to get away from the awful "extreme tiredness" language when it gets dumbed down into lay language.

That said I've no idea what a better wording would be, perhaps something about loss of function due to a failure of energy metabolism/production systems or something ...??

 

Good topic, @Ravn.

One way forward might be to replace the initial reference to fatigue and PEM in the introduction with a phrase I nicked from one of @Trish's posts: fatigue, rapid fatiguability, and post-exertional malaise (PEM).

It's neat because it challenges people to see there's a difference, and (hopefully) to think about it. Or at least, realise that it's not straightforward.

It describes the key features well in a few words, though I guess it could usefully be qualified. It probably isn't clear enough that it's not just about physical capacity, it applies to cognitive, sensory and emotional capacity too.

 

Personally, I'd like to see something that reflects the individual nature the disease can manifest itself in patients. (awkward wording, sorry)

Something that captures that ME/CFS is characterized by a symptom complex or amalgam. I'd emphasize those symptoms can vary by individual in frequency and intensity.

Then I'd list several of the most prevalent ones alphabetically to avoid prioritizing, but I'd asterisk PEM.

 

I think @Ravn 's basic idea is not to say anything much. Say the paper is about ME/CFS, just as you would say it is about MS or cancer, and assume the reader knows what you are talking about. Data papers are there to report observations relating to testing hypotheses. Reviews are there to tell people about diseases.

 

As a side note to mention without at this point feeling up to going into detail but I suspect with some of these - particularly where they might be studies that could be breakthroughs then I think some of this might be to do with the way articles work if it gets picked up by the media.

the 'impact' section also used to be the common area for this - where you had some complex philosophical thing or really tricky scientific finding but wanted to riff on 'what it could transform' or how it could be applicable in the real world. It's an actual obligation for departments and an important thing for academics too.

Of course that is also part of todays requirement for academic papers too (engagement and applicability to the real world). There is a whole category for 'impact' in the REF which is the research assessment exercise that goes on every 5-7years and is a massive thing because it is what is used to grade research and depts' quality of it, and is used in league tables etc.

And real-world applicability does relate to basics like we have a condition that affects these people to this extent and has a lifetime recovery of x and what is currently offered is a combo of zilch and wrong-headed with a side-helping of some getting some access to things other illnesses might have but it is very patchy and not touching the sides to stop most worsening.

I don't know whether the part that is different in ME is the section things go in because 1. there are so many different paradigms, some old ones of which work on old data (and you'd rather not have someone in a press office fishing around to fill any gaps they might have and either not publish or fill the gaps with info found elsewhere), 2. the info is the 'basics kind' which perhaps doesn't sit in the section at the end.

 

That's about sums it up. It's not about what should or should not be discussed, only which whats should be discussed where and when. There is a time and place for almost everything but that doesn't mean almost everything should go into the intro section

This might be part of the problem? Nobody has a good answer to this question?

Strictly speaking it shouldn't even be necessary to refer to a review but given authors and probably reviewers, too, are so habituated to providing paragraphs and paragraphs of general detail barely related to the specific topic of the study, going from that to nothing cold turkey might be too much to ask, having something sensible to point to could be a good middle way