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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 6,167 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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517 studies

E0 — Consensus643E1 — Replicated320E2 — Moderate2,782E3 — Preliminary2,422

ME/CFS4,025Long COVID217Post-infectious189Overlapping1,050

Required for diagnosis414Not specified / unclear2,219Not required3,534

Post-Exertional Malaise1,064Cognitive Dysfunction1,735Pain1,620Unrefreshing Sleep799Orthostatic Intolerance478

Cytokines818Gene Expression567Metabolomics473Neuroimaging468Autoantibodies458

Infection-Triggered1,174Long COVID Overlap588Pediatric493Severe231

Strong Phenotyping438Sex-Stratified326Severe ME Included118

Systematic Review265Meta-Analysis60RCT300

Peer-reviewed6,110Preprint3Unclear54

341–360 of 517 studies

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

An overview of operationalizing criteria for ME, ME/CFS, and CFS case definitions.

Jason, Leonard A, So, Suzanna, Evans, Meredyth et al.·Journal of prevention & intervention in the community·2015

This study looks at how researchers define and identify ME/CFS using different sets of criteria. The researchers examined various diagnostic guidelines to understand how they work in practice and what makes a good case definition. This work helps ensure that when doctors diagnose ME/CFS, they're using clear, consistent standards.

E3 PreliminaryReviewPEM unclearReview-Narrative

Medical constructions of long-term exhaustion, past and present.

Lian, Olaug S, Bondevik, Hilde·Sociology of health & illness·2015

This study looked at how doctors have understood exhaustion illnesses over time, comparing medical writings from 1860-1930 with those from 1970-2013. Researchers found that how these conditions were described and who had them changed dramatically: what was once seen as a physical disease affecting high-status men became viewed as a mental health problem affecting mostly women. The authors suggest these changes reflect cultural beliefs and values of each era, not just scientific discovery.

E3 PreliminaryCohortPEM not requiredCross-Sectional

Adolescents and mothers value referral to a specialist service for chronic fatigue syndrome or myalgic encephalopathy (CFS/ME).

Beasant, Lucy, Mills, Nicola, Crawley, Esther·Primary health care research & development·2014

This study asked 13 mothers and 12 teenagers with ME/CFS about their experiences getting help from a specialist ME/CFS service. Most families found it difficult and took a long time to access the specialist clinic, but once they got there, both teenagers and mothers felt it was valuable. The specialist service helped confirm the diagnosis, improved symptom management, and helped communication between doctors and schools.

InterventionsDiagnostics

E3 PreliminaryCohortPEM not requiredCase-Control

Epstein-barr virus infection masquerading as acute leukemia: a report of two cases and review of literature.

Chhabra, Puneet, Law, Arjun Dutt, Sharma, Upender et al.·Indian journal of hematology & blood transfusion : an official journal of Indian Society of Hematology and Blood Transfusion·2014

This study describes two cases where patients were initially thought to have acute leukemia based on blood tests, but they actually had Epstein-Barr virus (EBV) infections instead. One patient had infectious mononucleosis, and the other had a rare EBV-related immune condition. The study shows that EBV can sometimes look like leukemia under a microscope, which can lead to misdiagnosis.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic Fatigue Syndrome: Case Definitions and Diagnostic Assessment.

Williams, Yolonda J, Jantke, Rachel L, Jason, Leonard A·New York State psychologist·2014

This article explains why doctors have difficulty diagnosing ME/CFS and why patients often struggle to get proper care. The researchers found that there are disagreements about how to define and diagnose the illness, which makes it harder for healthcare providers to recognize it and treat it correctly. They call for better education of doctors and clearer diagnostic guidelines.

E3 PreliminaryReviewPEM unclearReview-Narrative

What is called symptom?

Eriksen, Thor Eirik, Risør, Mette Bech·Medicine, health care, and philosophy·2014

This paper explores what we actually mean by the word 'symptom' in medicine. The authors argue that when doctors can't find a clear medical cause for illness—like ME/CFS—our usual way of thinking about symptoms breaks down. They suggest we need to understand symptoms in broader ways, including how patients' social lives, personal experiences, and individual circumstances shape how they experience illness.

E3 PreliminaryCohortPEM not requiredObservational

Diagnosing Chronic Fatigue Syndrome in South Asians: Lessons from a Secondary Analysis of a UK Qualitative Study.

De Silva, R Erandie Ediriweera, Bayliss, Kerin, Riste, Lisa et al.·Journal of family medicine and primary care·2013

This study looked at why ME/CFS is rarely diagnosed in South Asia, even though people there experience its symptoms. By interviewing South Asian patients, doctors, and community leaders in the UK, researchers found that cultural beliefs, language barriers, and doctors' lack of knowledge about ME/CFS make it harder for people to get a proper diagnosis. The study suggests that raising awareness about ME/CFS in South Asia could help more people get diagnosed and treated.

E3 PreliminaryPEM not requiredRegistry-Resource

A pilot registry of unexplained fatiguing illnesses and chronic fatigue syndrome.

Brimmer, Dana J, Maloney, Elizabeth, Devlin, Rebecca et al.·BMC research notes·2013

This study tested whether doctors and patient groups could help identify people with ME/CFS for a patient registry (a database of medical information). Researchers in Georgia contacted healthcare providers and a local ME/CFS support group to refer patients for evaluation. Of 104 people who completed clinic visits, 36% had ME/CFS, 17% had fatigue that didn't quite meet ME/CFS criteria, and 47% had other medical or psychiatric conditions instead. This shows that many people with fatigue symptoms may have treatable conditions other than ME/CFS.

E3 PreliminaryReviewPEM unclearReview-Narrative

[Fatigue syndromes--an overview of terminology, definitions and classificatory concepts].

Dörr, Johanna, Nater, Urs·Psychotherapie, Psychosomatik, medizinische Psychologie·2013

This article reviews how doctors classify and differentiate between different fatigue conditions, including ME/CFS, burnout, and an older condition called neurasthenia. The authors found that while these conditions share some symptoms, they have important differences—but there currently isn't enough research to clearly separate them. Depression often occurs alongside ME/CFS and burnout, making diagnosis more complicated.

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

Method Issues in Epidemiological Studies of Medically Unexplained Symptom-based Conditions in Veterans.

Coughlin, Steven S, McNeil, Rebecca B, Provenzale, Dawn T et al.·Journal of military and veterans' health·2013

This study examined how researchers diagnose ME/CFS and related conditions in veterans, particularly those who served in the 1990-1991 Gulf War. The researchers found that many veterans had other medical conditions that could complicate or mask ME/CFS diagnosis. The study highlights that how doctors define and diagnose these conditions matters a lot, and different approaches can lead to very different results.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndrome in the UK armed forces.

Le Blackadder-Coward, J C Q, Perry, S·Journal of the Royal Naval Medical Service·2013

This study examined how ME/CFS (also called CFS) affects people serving in the UK military, and how the condition should be recognized and managed in this specific setting. ME/CFS can significantly impact a service member's career and ability to work in challenging military environments. The article discusses how doctors can better identify and treat this condition in military personnel.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic Lyme; diagnostic and therapeutic challenges.

Ljøstad, U, Mygland, Å·Acta neurologica Scandinavica. Supplementum·2013

This review discusses chronic Lyme disease, a rare condition caused by ongoing infection with the bacteria that causes Lyme disease. The main symptoms include progressive brain and spinal cord inflammation, skin changes, nerve damage, and joint pain. The authors explain how doctors can diagnose chronic Lyme using specific blood tests and cerebrospinal fluid tests, and recommend standard antibiotic treatment rather than experimental or prolonged approaches.

E3 PreliminaryReviewPEM unclearReview-Narrative

[Distinguishing between depression and chronic fatigue syndrome].

Asberg, Marie, Nygren, Ake, Nager, Anna·Lakartidningen·2013

This study examines how depression and ME/CFS are different conditions, even though they can look similar on the surface. The researchers discuss why it's important for doctors to tell these conditions apart, since they require different treatment approaches. Understanding these differences helps ensure patients get the right care for their specific condition.

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Minimum data elements for research reports on CFS.

Jason, Leonard A, Unger, Elizabeth R, Dimitrakoff, Jordan D et al.·Brain, behavior, and immunity·2012

Researchers noticed that different ME/CFS studies were collecting and reporting information in very different ways, making it hard to compare results across laboratories. This paper outlines the essential information that all ME/CFS research studies should include—like how patients were selected, what their characteristics are, and how they were tested—so that future studies can be compared fairly and findings can be better understood.

E3 PreliminaryReviewPEM unclearReview-Narrative

Chronic fatigue syndrome or myalgic encephalomyelitis.

Burns, Dianne·Nursing standard (Royal College of Nursing (Great Britain) : 1987)·2012

ME/CFS is a serious illness that affects many body systems, especially the nervous and immune systems, and can impact anyone regardless of age, race, or background. This guideline article helps nurses and healthcare workers recognize and support ME/CFS patients by providing practical knowledge and management strategies. The recommendations can be used by healthcare professionals in different settings to better care for people living with this condition.

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Developing resources to support the diagnosis and management of Chronic Fatigue Syndrome/Myalgic Encephalitis (CFS/ME) in primary care: a qualitative study.

Hannon, Kerin, Peters, Sarah, Fisher, Louise et al.·BMC family practice·2012

This study asked patients, carers, and doctors in North West England what would help them better diagnose and manage ME/CFS in general practice. The researchers found that patients want to be believed and taken seriously, while doctors said they need better training and support. Based on everyone's feedback, the team created practical tools including a DVD for patients, information leaflets, and online training for doctors.

E3 PreliminaryGuidelinePEM not requiredGuideline

[Persistent fatigue following Q fever].

Keijmel, Stephan P, Morroy, Gabriëlla, Delsing, Corine E et al.·Nederlands tijdschrift voor geneeskunde·2012

After a bacterial infection called Q fever, about 1 in 5 patients develop long-lasting fatigue and other symptoms called Q fever fatigue syndrome (QFS). This guideline from the Netherlands helps doctors diagnose and treat QFS consistently. Many patients recover on their own within six months, but those who don't may benefit from cognitive behavioral therapy, a type of talk therapy that helps people manage chronic fatigue.

E3 PreliminaryDiagnosticPEM unclearCross-Sectional

Fatigue Scales and Chronic Fatigue Syndrome: Issues of Sensitivity and Specificity.

Jason, Leonard A, Evans, Meredyth, Brown, Molly et al.·Disability studies quarterly·2011

This study tested different questionnaires and scales designed to measure fatigue in ME/CFS patients to see how well they could identify people with the disease. Researchers found that most common fatigue measurement tools didn't work very well—some were good at spotting sick people but missed others, or vice versa. The most promising tool was a specific question about fatigue that gets worse after physical activity, which is a key feature of ME/CFS.

E3 PreliminaryCommentaryPEM unclearEditorial

Diagnosis and management of fibromyalgia: how and why.

Hayhoe, Simon·Pain management·2011

Fibromyalgia is a condition causing widespread muscle pain, tiredness, and sleep problems that doctors still debate about. It shares some features with ME/CFS and may involve both physical changes in how the nervous system processes pain and psychological factors. Treatment typically includes certain antidepressants, anti-seizure medications, and talking therapy with gentle exercise, though most patients only get partial improvement.

E3 PreliminaryCohortPEM not required

Decades of delayed diagnosis in 4 levodopa-responsive young-onset monogenetic parkinsonism patients.

Ling, Helen, Braschinsky, Mark, Taba, Pille et al.·Movement disorders : official journal of the Movement Disorder Society·2011

This study describes four young patients who were initially misdiagnosed with psychological movement disorders or chronic fatigue syndrome, but actually had a genetic form of Parkinson's disease. Their misdiagnosis lasted 10 to 23 years before the correct diagnosis was made. Once they received the correct treatment with levodopa medication, they all improved significantly, showing that the right diagnosis and treatment can make a major difference.

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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.