Skip to content

Start Here
Atlas
Evidence
Research
Ask
Updates
About
Support

Evidence Atlas

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

Start Here
Atlas
Evidence
Research
Ask
FAQ
Glossary
Updates
Methodology
Press
Retractions
Contribute
About
Support
Contact

Weekly research digest — no spam

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.

Generator v1·Scanner v1.4·Lint gate: enforce·See methodology

© 2026 ME/CFS Atlas

ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

Evidence browser

Search and filter 6,171 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 →

Sort

1198 studies

E0 — Consensus644E1 — Replicated320E2 — Moderate2,785E3 — Preliminary2,422

ME/CFS4,028Long COVID217Post-infectious189Overlapping1,051

Required for diagnosis415Not specified / unclear2,222Not required3,534

Post-Exertional Malaise1,067Cognitive Dysfunction1,737Pain1,621Unrefreshing Sleep800Orthostatic Intolerance479

Cytokines819Gene Expression568Metabolomics475Neuroimaging468Autoantibodies458

Infection-Triggered1,175Long COVID Overlap589Pediatric494Severe231

Strong Phenotyping439Sex-Stratified327Severe ME Included118

Systematic Review266Meta-Analysis60RCT300

Peer-reviewed6,114Preprint3Unclear54

561–580 of 1,198 studies

E2 ModerateCohortPEM not requiredObservational

The value of the dehydroepiandrosterone-annexed vitamin C infusion treatment in the clinical control of chronic fatigue syndrome (CFS). II. Characterization of CFS patients with special reference to their response to a new vitamin C infusion treatment.

Kodama, M, Kodama, T, Murakami, M·In vivo (Athens, Greece)·1996

This 1996 study examined whether high-dose vitamin C infusions, with or without a hormone called DHEA added, could help treat ME/CFS. Researchers treated 313 patients with chronic pneumonia-like illness that matched ME/CFS symptoms, often combined with antibiotics. The authors found that the combination of two types of vitamin C infusions worked better than one type alone, suggesting that low levels of certain body hormones might play a role in ME/CFS.

E2 ModerateCohortPEM unclearCross-Sectional

Viral serologies in patients with chronic fatigue and chronic fatigue syndrome.

Buchwald, D, Ashley, R L, Pearlman, T et al.·Journal of medical virology·1996

Researchers tested 548 people with chronic fatigue to see if they had unusually high levels of antibodies to 13 common viruses, since ME/CFS often starts suddenly after a viral illness. They compared antibody levels in patients with chronic fatigue to healthy controls and found no consistent differences between the groups, suggesting these particular virus tests are not helpful in diagnosing or understanding chronic fatigue.

E2 ModerateCohortPEM unclearCross-Sectional

High incidence of antibodies to 5-hydroxytryptamine, gangliosides and phospholipids in patients with chronic fatigue and fibromyalgia syndrome and their relatives: evidence for a clinical entity of both disorders.

Klein, R, Berg, P A·European journal of medical research·1995

Researchers found that patients with ME/CFS and fibromyalgia syndrome (FMS) often have similar antibodies in their blood—proteins the immune system produces that may attack the body's own tissues. About 62% of ME/CFS patients and 73% of FMS patients had antibodies against serotonin, a chemical important for mood and pain regulation. Interestingly, these antibodies were also found in family members of affected patients, suggesting a genetic component may play a role.

E2 ModerateCohortPEM not requiredCross-Sectional

Human herpesvirus 6 and human herpesvirus 7 in chronic fatigue syndrome.

Di Luca, D, Zorzenon, M, Mirandola, P et al.·Journal of clinical microbiology·1995

Researchers looked for two common viruses (HHV-6 and HHV-7) in immune cells of ME/CFS patients and compared them to healthy people. They found that HHV-7 was equally common in both groups, but a specific type of HHV-6 called variant A was found more often in ME/CFS patients. This suggests that HHV-6 variant A may be connected to ME/CFS, though the study does not prove it causes the illness.

E2 ModerateCohortPEM not requiredCross-Sectional

Abnormalities of carnitine metabolism in chronic fatigue syndrome.

Majeed, T, de Simone, C, Famularo, G et al.·European journal of neurology·1995

This study examined carnitine, a substance that helps cells produce energy, in people with ME/CFS. Researchers found that while carnitine levels in the blood were normal, the levels inside immune cells were significantly lower in ME/CFS patients compared to healthy people. This finding suggests that ME/CFS patients might benefit from taking carnitine supplements to restore normal energy production.

E2 ModerateCohortPEM not requiredCase-Control

Seroepidemiology of chronic fatigue syndrome: a case-control study.

Mawle, A C, Nisenbaum, R, Dobbins, J G et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1995

Researchers tested people with ME/CFS and healthy control groups for antibodies to many common viruses, including herpesviruses and enteroviruses. They found no differences between the two groups—patients with ME/CFS did not have higher levels of antibodies to any of the viruses tested. This suggests that recent or past infection with these particular viruses is not a distinguishing feature of ME/CFS.

E2 ModerateCohortPEM not requiredCase-Control

Clinical laboratory test findings in patients with chronic fatigue syndrome.

Bates, D W, Buchwald, D, Lee, J et al.·Archives of internal medicine·1995

Researchers compared blood test results from 579 ME/CFS patients with results from 147 healthy people. They found that ME/CFS patients were much more likely to have certain abnormal results, particularly immune-related changes like unusual white blood cells and immune complexes. However, no single test was abnormal enough in all patients to serve as a reliable diagnostic tool on its own.

BiomarkersImmune System

E2 ModerateCohortPEM not requiredCross-Sectional

Frequency of deviant immunological test values in chronic fatigue syndrome patients.

Natelson, B H, Ellis, S P, Braonáin, P J et al.·Clinical and diagnostic laboratory immunology·1995

Researchers tested 11 different immune system markers in ME/CFS patients and compared them to fatigued people without ME/CFS. They found that three immune tests (protein A binding, Raji cell test, and complement proteins C3 or C4) showed different results between the groups. However, most other immune tests they looked at, including antibody levels and other complement markers, did not reliably distinguish ME/CFS patients from those with other causes of fatigue.

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence of IgM antibodies to human herpesvirus 6 early antigen (p41/38) in patients with chronic fatigue syndrome.

Patnaik, M, Komaroff, A L, Conley, E et al.·The Journal of infectious diseases·1995

Researchers tested whether people with ME/CFS have more signs of a virus called human herpesvirus 6 (HHV-6) compared to healthy people. They found that 77% of ME/CFS patients had antibodies suggesting exposure to or active HHV-6 infection, compared to only 12% of healthy controls. This suggests HHV-6 may be more common in people with ME/CFS, though it's unclear whether the virus causes the illness or is simply more active in these patients.

E2 ModerateCohortPEM not requiredCross-Sectional

Silicone breast implant--associated musculoskeletal manifestations.

Cuellar, M L, Gluck, O, Molina, J F et al.·Clinical rheumatology·1995

This study looked at 300 women with silicone breast implants who came to a rheumatology clinic with muscle and joint pain. The researchers found that over 80% of these women had signs of connective tissue disease, and more than half met criteria for fibromyalgia or chronic fatigue syndrome. When some women had their implants removed, over 70% reported improvement in their overall symptoms.

E2 ModerateCohortPEM not requiredObservational

Cell-mediated immune function and the outcome of chronic fatigue syndrome.

Wilson, A, Hickie, I, Lloyd, A et al.·International journal of immunopharmacology·1995

Researchers followed 103 ME/CFS patients for an average of 3.2 years to see if their immune system function predicted how well they would recover. Most patients improved over time, but about one-third remained unable to work. The study found that immune cell measurements taken at the start did not seem to predict who would get better or worse.

E2 ModerateCohortPEM not requiredCase-Control

Prevalence of human herpesvirus 6 variants A and B in patients with chronic fatigue syndrome.

Yalcin, S, Kuratsune, H, Yamaguchi, K et al.·Microbiology and immunology·1994

Researchers tested blood samples from 13 ME/CFS patients and 13 healthy people to see if they carried human herpesvirus 6 (HHV-6), a common virus that most people encounter in childhood. They found that over half of the ME/CFS patients had active HHV-6 in their blood, while none of the healthy controls did. The patients also had higher antibody levels, suggesting their immune systems were actively fighting the virus.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Psychobehavioral and immunological characteristics of adult people with chronic fatigue and patients with chronic fatigue syndrome.

Masuda, A, Nozoe, S I, Matsuyama, T et al.·Psychosomatic medicine·1994

This study compared immune system function and psychological stress levels in three groups: healthy people, those with chronic fatigue (but not ME/CFS), and patients with ME/CFS. All three groups showed differences in how stressed they felt, their activity levels, and how well their immune cells (specifically natural killer cells) worked. Importantly, the chronic fatigue group fell somewhere between healthy people and ME/CFS patients in terms of both psychological stress and immune function.

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue syndrome--a controlled cross sectional study.

Rasmussen, A K, Nielsen, H, Andersen, V et al.·The Journal of rheumatology·1994

Researchers compared immune system markers in 21 people with ME/CFS to 21 healthy controls to see if immune problems might cause the illness. They found that people with ME/CFS produced higher levels of certain immune signaling molecules and had slightly different antibody patterns, but overall immune system differences between the groups were small. The study suggests the immune system may be out of balance in ME/CFS, but doesn't prove this imbalance actually causes the disease.

E2 ModerateCohortPEM not requiredCross-Sectional

[Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes].

Hilgers, A, Frank, J·Wiener medizinische Wochenschrift (1946)·1994

This study examined 375 patients with ME/CFS to understand what goes wrong with their immune systems and which infections might be involved. Researchers found that most patients had problems with immune cell function, signs of past viral infections (especially Epstein-Barr virus), and imbalances in immune chemicals. The study suggests ME/CFS may be connected to autoimmune problems and multiple infections.

E2 ModerateCohortPEM not requiredCross-Sectional

[Viral infection and fibromyalgia].

Branco, J C, Tavares, V, Abreu, I et al.·Acta medica portuguesa·1994

This study looked at whether a common virus called parvovirus B19 might be responsible for fibromyalgia, a condition similar to ME/CFS that causes widespread pain and fatigue. Researchers compared blood antibodies (which show past infection) in 52 fibromyalgia patients versus 39 healthy people. They found slightly higher rates of past parvovirus infection in fibromyalgia patients, but the difference was too small to be meaningful, so they concluded the virus is probably not the cause of fibromyalgia.

E2 ModerateCohortPEM not requiredCross-Sectional

[Chronic fatigue syndrome--a controlled cross-sectional study].

Rasmussen, A K, Nielsen, H, Andersen, V et al.·Ugeskrift for laeger·1994

This study compared immune system markers in 21 people with ME/CFS to 21 healthy people matched by age and sex. Researchers found that certain immune cells in ME/CFS patients produced higher levels of specific immune signaling molecules, while antibody levels were slightly lower than normal. Overall, the study did not find clear evidence that ME/CFS is caused by a persistent viral infection or a severely damaged immune system.

E2 ModerateCohortPEM not requiredCross-Sectional

A potential role for human herpesvirus type 6 in nervous system disease.

Wilborn, F, Schmidt, C A, Brinkmann, V et al.·Journal of neuroimmunology·1994

This study looked for evidence that human herpesvirus type 6 (HHV-6), a common virus, might be involved in nervous system diseases including ME/CFS. Researchers tested blood and spinal fluid samples from patients with different neurological conditions and compared them to healthy controls. They found that a small number of multiple sclerosis patients had HHV-6 DNA in their spinal fluid, and MS patients had higher antibodies to HHV-6 in their blood, suggesting the virus may play a role in that disease.

E2 ModeratePEM not requiredRegistry-Resource

An approach to studies of cancer subsequent to clusters of chronic fatigue syndrome: use of data from the Nevada State Cancer Registry.

Levine, P H, Atherton, M, Fears, T et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study looked at whether people in Nevada who developed a CFS-like illness in the mid-1980s had higher rates of cancer, particularly brain tumors and lymphoma, in the years that followed. Researchers checked cancer registry records to see if there was a connection. They found a slight increase in brain tumors but no clear pattern for lymphoma, though they noted the brain tumor trend might reflect a nationwide pattern rather than something specific to CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

Immunologic abnormalities associated with chronic fatigue syndrome.

Barker, E, Fujimura, S F, Fadem, M B et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study examined immune cells in the blood of ME/CFS patients and compared them to healthy people. Researchers found that ME/CFS patients had normal numbers of immune cells overall, but the cells showed signs of being overactive and tired. Most notably, patients had significantly reduced natural killer cell activity—these are immune cells that normally help fight infections and abnormal cells.

← Previous Next 20 studies →

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.