[Definition of the chronic fatigue syndrome and its issues].
Hashimoto, N · Nihon rinsho. Japanese journal of clinical medicine · 1992
Quick Summary
This article reviews how ME/CFS was officially defined by the CDC in 1988 and identifies problems with that definition. The author points out that while the definition tries to rule out other conditions, it has trouble distinguishing ME/CFS from similar conditions like fibromyalgia and depression, and it's difficult to measure in real-world clinical practice.
Why It Matters
Diagnostic criteria are fundamental to clinical practice and research. This early critical examination of the CDC definition helped identify structural weaknesses that would eventually lead to refined diagnostic criteria (such as the Fukuda criteria refinements and later the International Consensus Criteria), improving how ME/CFS patients are identified and studied.
Observed Findings
The 1988 CDC definition cannot adequately exclude fibromyalgia based on the myalgia criterion alone
The definition cannot reliably distinguish depression from ME/CFS using its existing criteria
Measuring 50% impairment in premorbid activity level is impractical for clinical application, particularly at first patient visit
The CDC definition does not address postviral fatigue syndrome or myalgic encephalomyelitis concepts
The definition does not discuss whether epidemic versus sporadic presentations exist
Inferred Conclusions
The 1988 CDC definition of CFS has significant limitations that reduce its clinical utility
Improved diagnostic criteria are necessary to better distinguish ME/CFS from overlapping conditions such as fibromyalgia and depression
A more practical definition that can be applied at initial clinical evaluation is needed
Future definitions should address the relationship between CFS, postviral fatigue, and myalgic encephalomyelitis
Remaining Questions
What diagnostic criteria would optimally distinguish ME/CFS from fibromyalgia and depression while remaining clinically practical?
What This Study Does Not Prove
This review does not provide new empirical data or test alternative diagnostic criteria. It does not prove what the correct definition should be, nor does it establish the prevalence or etiology of ME/CFS. This is a critical analysis rather than a study generating primary evidence.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →