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ME/CFS Atlas — A public knowledge atlas for ME/CFS

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ME/CFS Atlas is an evidence reference platform, not a medical provider. Content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.

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ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

Evidence browser

Search and filter 6,145 studies by evidence level, diagnostic criteria, PEM status, and research domain. Each entry links to the original source.

Studies sorted by evidence level, then year. Browse by topic instead →

Evidence level (E0–E3) reflects study type and replication, not methodological quality. A weak systematic review still sits at E0. How evidence levels work →

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510 studies

E0 — Consensus637E1 — Replicated320E2 — Moderate2,768E3 — Preliminary2,420

ME/CFS4,014Long COVID212Post-infectious189Overlapping1,045

Required for diagnosis412Not specified / unclear2,201Not required3,532

Post-Exertional Malaise1,055Cognitive Dysfunction1,723Pain1,612Unrefreshing Sleep793Orthostatic Intolerance474

Cytokines816Gene Expression567Metabolomics469Neuroimaging466Autoantibodies457

Infection-Triggered1,170Long COVID Overlap580Pediatric492Severe228

Strong Phenotyping435Sex-Stratified326Severe ME Included116

Systematic Review263Meta-Analysis60RCT300

Peer-reviewed6,088Preprint3Unclear54

421–440 of 510 studies

E3 PreliminaryReviewPEM unclearReview-Narrative

Understanding chronic fatigue syndrome: an empirical guide to assessment and treatment.

Johnson, S K·Journal of health psychology·1999

This 1999 guide provides healthcare providers and patients with practical methods for evaluating and treating chronic fatigue syndrome (ME/CFS). The authors reviewed existing evidence to create a framework for assessment—including tests and questionnaires—and outlined treatment approaches. This work aims to help clinicians better recognize and manage ME/CFS in their patients.

E3 PreliminaryReviewPEM unclearReview-Narrative

Report of a workshop on the epidemiology, natural history, and pathogenesis of chronic fatigue syndrome in adolescents.

Marshall, G S·The Journal of pediatrics·1999

This 1999 workshop report brought together experts to discuss what was known about ME/CFS in teenagers. The report summarized information about how common the illness is, how it develops over time, and what might cause it in young people. It served as an important step in recognizing that ME/CFS affects adolescents and that they needed specialized attention.

E3 PreliminaryReviewPEM unclearReview-Narrative

The importance of orthostatic intolerance in the chronic fatigue syndrome.

Schondorf, R, Freeman, R·The American journal of the medical sciences·1999

This review examines how problems with standing up (orthostatic intolerance) are connected to ME/CFS. Many people with ME/CFS experience symptoms like dizziness, fatigue, trouble concentrating, shaking, and nausea when standing or sitting upright. The authors review what we know about this connection, including how to diagnose it, what tests can help, what might cause it, and how it might be treated.

Autonomic Nervous SystemDiagnostics

E3 PreliminaryPEM not requiredRegistry-Resource

The Chronic Fatigue Twin Registry: method of construction, composition, and zygosity assignment.

Buchwald, D, Herrell, R, Ashton, S et al.·Twin research : the official journal of the International Society for Twin Studies·1999

Researchers created a registry of twin pairs where at least one person had chronic fatigue to better understand the condition. They recruited 204 twin pairs through support groups, doctors, and other sources, and had 177 complete their detailed questionnaires and phone interviews. This registry was designed to help scientists study what causes chronic fatigue and whether genetics or life circumstances play a bigger role.

E3 PreliminaryReviewPEM unclearReview-Narrative

[The chronic fatigue syndrome--a clinical entity or a complex of symptoms of various pathologic conditions].

Magdić, B, Ilić, T, Jovankić, O et al.·Vojnosanitetski pregled·1999

This paper examines whether ME/CFS is a single distinct disease or whether it might actually be a collection of different medical conditions that share similar symptoms. The authors review the clinical characteristics and evidence to help determine what ME/CFS really is from a medical standpoint.

E3 PreliminaryCohortPEM not requiredCase-Control

Recognition of chronic carbon monoxide poisoning.

Knobeloch, L, Jackson, R·WMJ : official publication of the State Medical Society of Wisconsin·1999

This study describes three families in Wisconsin whose members were diagnosed with chronic fatigue syndrome, depression, and other illnesses that turned out to be caused by carbon monoxide leaks from faulty home heating systems. The families' symptoms—including fatigue, headaches, dizziness, and confusion—went undiagnosed until heating contractors found the problem. The authors remind doctors to consider carbon monoxide poisoning when patients have vague, ongoing symptoms, especially during winter.

E3 PreliminaryReviewPEM unclearReview-Narrative

[Similarities of chronic fatigue syndrome, fibromyalgia and multiple chemical sensitivity].

Csef, H·Deutsche medizinische Wochenschrift (1946)·1999

This study looked at three conditions—chronic fatigue syndrome (ME/CFS), fibromyalgia, and multiple chemical sensitivity—to see if they share similarities. The researchers examined how these conditions might be related to each other based on their common features. Understanding these connections could help doctors better recognize and treat patients who experience overlapping symptoms across these conditions.

E3 PreliminaryGuidelinePEM not requiredGuideline

Social Security Ruling, SSR 99-2p.; titles II and XVI; evaluating cases involving chronic fatigue syndrome (CFS). Social Security Administration. Notice of Social Security ruling.

Federal register·1999

The Social Security Administration issued an official ruling in 1999 to help people with ME/CFS get disability benefits. The ruling states that ME/CFS is a real medical condition that can prevent someone from working, but only when doctors find specific signs or lab results that support the diagnosis. This ruling was meant to make sure all disability examiners across the country evaluate ME/CFS cases using the same fair standards.

E3 PreliminaryReviewPEM unclearReview-Narrative

Chronic fatigue syndrome and fibromyalgia. Dilemmas in diagnosis and clinical management.

Demitrack, M A·The Psychiatric clinics of North America·1998

This article reviews what we know about ME/CFS and fibromyalgia, two conditions that cause severe tiredness and pain and are often misunderstood. The authors explain that these illnesses involve both physical and mental health factors working together, rather than being purely 'in your head' or purely physical. They provide doctors with practical guidelines for better diagnosis and treatment of these challenging conditions.

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Fibromyalgia. A critical review].

Cathébras, P, Lauwers, A, Rousset, H·Annales de medecine interne·1998

Fibromyalgia is a chronic pain condition that affects about 2% of the general population, with symptoms including widespread pain, fatigue, and sleep problems. This review examines how fibromyalgia overlaps with other conditions like ME/CFS and depression, and discusses why current treatments like antidepressants and therapy have limited effectiveness. The authors suggest that fibromyalgia may develop through interconnected factors rather than a single cause.

SleepDiagnostics

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndrome: a review for clinicians.

Goshorn, R K·Seminars in neurology·1998

This review explains that ME/CFS is a real condition characterized by long-lasting fatigue, muscle and joint pain, sleep problems, and thinking difficulties. While doctors don't yet fully understand what causes ME/CFS, research suggests it involves subtle problems with the nervous system, hormones, and immune function. Treatment focuses on managing symptoms to help patients feel better, though the approach is personalized since every patient is different.

E3 PreliminaryCohortPEM unclear

Chronic fatigue syndrome: chronic ciguatera poisoning as a differential diagnosis.

Pearn, J H·The Medical journal of Australia·1997

This study examines whether some people diagnosed with ME/CFS might actually have chronic ciguatera poisoning, a illness caused by eating contaminated seafood. The researchers suggest that certain ME/CFS cases could be misdiagnosed cases of ciguatera, which can cause similar long-lasting fatigue and other symptoms. The study calls for doctors to consider this possibility when evaluating patients with ME/CFS symptoms.

E3 PreliminaryCohortPEM unclear

A 56-year-old woman with chronic fatigue syndrome.

Komaroff, A L·JAMA·1997

This case study describes one patient's experience with ME/CFS, detailing her symptoms, medical history, and clinical presentation. The study provides an in-depth look at how ME/CFS affects a real person and what doctors observed during evaluation. This type of detailed patient story can help both patients and doctors better understand the condition.

E3 PreliminaryReviewPEM unclearReview-Narrative

Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome.

Goldenberg, D L·Current opinion in rheumatology·1997

This review examines three related conditions—fibromyalgia, ME/CFS, and myofascial pain syndrome—and discusses ongoing challenges in diagnosing and treating them. The study found that psychiatric conditions are not a core feature of these diseases, but rather reflect that people with these conditions are more likely to seek medical help. The researchers identified that a blood pressure problem called neurally mediated hypotension may play a role in ME/CFS, and that treating patients in multidisciplinary groups (rather than in isolation) showed more promise than traditional individual treatments.

Autonomic Nervous SystemDiagnostics

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Chronic fatigue syndrome].

van der Meer, J W·Nederlands tijdschrift voor geneeskunde·1997

This review examines different theories about what causes ME/CFS, ranging from persistent infections and metabolic problems to psychiatric factors. While many potential causes have been proposed—including lingering infections, toxins, immune system problems, nervous system dysfunction, and hormone imbalances—none have been definitively proven. The authors note that psychological factors play an important role in how the illness develops and can be helpful in treating patients.

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Definition of "chronic fatigue syndrome" (CFS)].

Heyll, U, Wachauf, P, Senger, V et al.·Medizinische Klinik (Munich, Germany : 1983)·1997

In 1988, doctors created an official definition for chronic fatigue syndrome (CFS) to help researchers study it consistently. However, this study found that the original definition didn't work as well as hoped—it didn't capture the condition accurately, and patients with CFS turned out to be quite different from each other. The authors suggest that CFS should be understood as a descriptive condition rather than a single disease with one cause.

E3 PreliminaryCohortPEM not requiredCase-Control

[Chronic fatigue--'tired with 23 i's'].

van der Meer, J W, Elving, L D·Nederlands tijdschrift voor geneeskunde·1997

This study describes two patients with severe tiredness. One woman had chronic fatigue syndrome and improved slowly over time, while one man's exhaustion was caused by a treatable pituitary gland tumor that was removed surgically. The doctors emphasize that it's important to thoroughly examine patients to find out if something else is causing their tiredness before diagnosing chronic fatigue syndrome.

E3 PreliminaryGuidelinePEM not requiredGuideline

Chronic fatigue syndrome. A practical guide to assessment and management.

Sharpe, M, Chalder, T, Palmer, I et al.·General hospital psychiatry·1997

This guide explains how doctors should assess and manage ME/CFS by building trust with patients, taking a detailed history, and ruling out other conditions. Treatment focuses on helping patients understand their illness, establish consistent activity and sleep patterns, and gradually return to normal activities, with cognitive behavioral therapy being the only proven effective approach. The authors emphasize that ME/CFS is a real, treatable condition and provide practical strategies to help patients avoid misinterpreting their symptoms or fearing activity.

E3 PreliminaryGuidelinePEM not requiredGuideline

[Indications for management in long-term, physically unexplained fatigue symptoms].

van der Meer, J W, Rijken, P M, Bleijenberg, G et al.·Nederlands tijdschrift voor geneeskunde·1997

This guideline, developed by Dutch doctors and health officials, suggests that chronic fatigue lasting more than 6 months without a clear medical cause should be managed differently depending on how long someone has had it. Rather than continuously searching for hidden causes, patients are encouraged to gradually rebuild activity using a structured schedule and focus on overall health promotion.

E3 PreliminaryPEM unclear

Meeting the frustrations of chronic fatigue syndrome.

Plioplys, A V, Plioplys, S, Davis, J S·Hospital practice (1995)·1997

This article discusses the challenges that ME/CFS patients face, including long-lasting disability and doctors who may not understand or believe in the condition. The authors explain that while there are no blood tests that definitively prove ME/CFS, doctors can confidently diagnose it using established criteria and ruling out other diseases. They suggest that medications can help manage symptoms while patients work toward recovery.

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Or browse by topic

PEM Immune Neuro Metabolic Biomarkers Severe ME Long COVID Cognitive

Curated Collections

Thematic groupings by clinical question or research area.

Neuroinflammation Evidence

PET imaging and other studies providing evidence for brain inflammation in ME/CFS.

Metabolism & Mitochondria

Metabolomics and mitochondrial function studies revealing energy metabolism disruption.

Biomarkers

Studies identifying potential biological markers for ME/CFS diagnosis and stratification.

PEM-Specific Research

Studies specifically examining post-exertional malaise, the hallmark symptom of ME/CFS.