Search and filter 6,205 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 →
281–300 of 533 studies
Zala, J·The Practitioner·1989
This study looked at how doctors can diagnose ME/CFS, especially when standard blood tests don't show clear evidence of infection. Researchers compared patients who had lab evidence of infection with those who didn't, and discussed what doctors should look for to make a reliable diagnosis based on symptoms and clinical presentation alone.
Kruesi, M J, Dale, J, Straus, S E·The Journal of clinical psychiatry·1989
This study looked at 28 patients with ME/CFS to see how often they had been diagnosed with psychiatric conditions like depression. The researchers found that psychiatric diagnoses were common in this group. Importantly, when they reviewed medical records, they discovered that most of these psychiatric conditions had started before the ME/CFS illness began, not after.
Manu, P, Lane, T J, Matthews, D A·Annals of internal medicine·1988
This study looked at 135 people with severe fatigue lasting at least 6 months to see how many actually had ME/CFS. The researchers found that only 6 patients (about 4%) met the criteria for ME/CFS, while most of the others had psychiatric conditions like depression or anxiety that were causing their fatigue. This suggests that ME/CFS is quite rare among people presenting with fatigue symptoms.
Walther, H·Schweizerische Rundschau fur Medizin Praxis = Revue suisse de medecine Praxis·1972
This 1972 case study describes an outbreak of myalgic encephalomyelitis (ME), a serious illness causing muscle pain, brain inflammation, and extreme fatigue. The author documented patients who experienced this epidemic, helping early medical professionals recognize and understand the disease pattern.
Li, Nathan, Cooper, Joshua, Fleming, Tanisha et al.·Psychopharmacology bulletin·2026
This article reviews what doctors and researchers currently understand about fibromyalgia, a chronic condition causing widespread pain and many other symptoms. While the exact causes remain unclear, scientists are finding potential clues in brain imaging, genes, and gut bacteria. The article explains how doctors diagnose fibromyalgia and what treatment options are available, emphasizing that managing it often requires a team approach with different specialists.
Oue, Yuri, Saiki, Ryosuke, Murata, Tomohiro et al.·Reports (MDPI)·2026
This case report describes a 60-year-old woman who was initially misdiagnosed with chronic fatigue syndrome when she actually had sarcoidosis (an inflammatory disease) affecting her kidneys. Doctors discovered this by finding very high levels of a protein called β2-microglobulin in her urine, which led to a kidney biopsy that confirmed the diagnosis. After treatment with a steroid medication, her kidney function improved and her fatigue completely resolved.
Coskun Benlidayi, Ilke, Ornek, Ceren, Deniz, Volkan et al.·Rheumatology international·2025
This review suggests that doctors could better diagnose fibromyalgia by adding a simple physical test—checking how strongly your reflexes react when tapped—to the current diagnostic methods. Right now, fibromyalgia is diagnosed mainly based on what patients report about their pain and symptoms, which can lead to missed or incorrect diagnoses. The researchers found that people with fibromyalgia often have stronger-than-normal reflex responses, which could help doctors rule out fibromyalgia or confirm it alongside other tests.
Vallings, Rosamund·Methods in molecular biology (Clifton, N.J.)·2025
This guide explains how experienced doctors diagnose ME/CFS when standard blood tests or scans cannot detect the illness. Since there is no single definitive test for ME/CFS, doctors must carefully evaluate a patient's symptoms, medical history, and how the illness affects their daily functioning. This chapter walks through the practical steps clinicians use to identify ME/CFS and distinguish it from other conditions.
Hammer, Sabine, Monaca, Clara, Hoelz, Annika et al.·Zeitschrift fur Evidenz, Fortbildung und Qualitat im Gesundheitswesen·2025
This study asked 264 long COVID patients about their experiences with doctors and healthcare services. Most patients reported that healthcare providers don't understand their condition, often dismiss it as psychological, and sometimes recommend treatments that make them sicker. Patients felt stigmatized and unsupported, with some waiting up to two years just to see a specialist.
Brimmer, Dana J, Lin, Jin-Mann S, Selinger, Howard A et al.·MedEdPORTAL : the journal of teaching and learning resources·2025
This study tested whether a short educational program could help future doctors, nurses, and physician assistants better understand pediatric ME/CFS. After a 40-minute lesson with videos and materials, students showed major improvements in recognizing ME/CFS as a real medical condition and felt more confident talking to patients about it. The results suggest that better training about ME/CFS in medical schools could help young patients get diagnosed and treated more effectively.
Harwood, Rupert, Wincup, Chris, D'Cruz, David et al.·Lupus·2025
This study looked at why people with lupus (SLE) often wait a long time to get diagnosed. Researchers found that doctors sometimes overlook or misinterpret lupus symptoms, attributing them instead to other causes like mental health problems, ME/CFS, or fibromyalgia. This "diagnostic overshadowing" can add years to someone's diagnostic journey and delay the treatment they need.
Lofrano-Porto, Adriana, D'Isabel, Susanne, Smith, Denise L·Frontiers in medicine·2024
This article reviews what we know about long COVID fatigue, especially in firefighters and other public safety workers. The authors explain why fatigue after COVID is so hard to diagnose and treat, since patients often look healthy on the outside even though they feel extremely tired. They describe possible biological reasons for this fatigue and discuss why it matters for workers whose jobs require them to be physically and mentally alert.
Jackson, Sally·Journal of health communication·2024
This paper examines how major disagreements about health topics—including ME/CFS—develop and persist over long periods of time across different countries and communities. The author explains that these health controversies involve many people with different viewpoints who argue in multiple places (medical journals, courts, social media, etc.), and that how we manage these disagreements matters. The study shows that ME/CFS is a particularly important example because disagreements about it have shaped how institutions are designed to handle health disputes.
Malato, João, Graça, Luís, Sepúlveda, Nuno·Diagnostics (Basel, Switzerland)·2023
This study examined how misdiagnosis affects ME/CFS research results. The researchers found that when patients are incorrectly diagnosed with ME/CFS (or vice versa), it becomes much harder for studies to find real connections between potential causes and the disease. To get reliable results, studies need to include at least 500-1000 people per group, which is larger than many current ME/CFS studies.
Froehlich, Laura, Niedrich, Jasmin, Hattesohl, Daniel B R et al.·Healthcare (Basel, Switzerland)·2023
Many doctors and health professionals don't know enough about ME/CFS, which makes it harder for patients to get proper care. Researchers created an online webinar to teach German-speaking healthcare workers about ME/CFS and tested whether it helped them learn. The study found that the webinar successfully increased doctors' knowledge about the illness, suggesting that online education could be a practical way to train more healthcare providers.
El Moussaoui, Majdouline, Guiot, Julien, Frippiat, Frédéric et al.·Revue medicale de Liege·2023
Some people who had COVID-19 develop long-lasting symptoms months or years after infection, a condition called long COVID. These symptoms include severe fatigue, muscle pain, shortness of breath, and neurological problems that are similar to those seen in ME/CFS. This review examines what we know about who develops long COVID, what causes it, and how doctors currently diagnose and treat it.
Gramont, B, Goutte, J, Féasson, L et al.·La Revue de medecine interne·2023
When people feel tired all the time, doctors need to figure out why. This article explains how doctors should approach chronic fatigue: by asking careful questions, doing a physical exam, and using only necessary blood tests. It emphasizes that chronic fatigue often has multiple causes—physical, emotional, and life circumstances—working together, and that exercise testing and personalized activity programs are the most helpful treatments.
Lacasa, Marcos, Prados, Ferran, Alegre, José et al.·Scientific reports·2023
This study created an artificial intelligence tool that can predict what ME/CFS patients might answer on symptom questionnaires. Researchers trained the tool using responses from 2,522 ME/CFS patients from a hospital in Spain, and it learned to predict answers accurately. The tool could help researchers study the disease more easily by generating realistic patient data for testing new ideas.
Schutzer, Steven E, Liu, Tao, Tsai, Chia-Feng et al.·Annals of medicine·2023
Researchers examined the fluid surrounding the brain and spinal cord in people with ME/CFS—some of whom also had fibromyalgia and some who did not. Using advanced technology to measure thousands of proteins in this fluid, they found no significant differences between the two groups. This suggests that ME/CFS and fibromyalgia may not be completely separate diseases, but rather may overlap or be related conditions.
Jason, Leonard A, Natelson, Benjamin H, Bonilla, Hector et al.·Brain behavior and immunity integrative·2023
This article reviews 40 years of research on ME/CFS to provide guidance for scientists studying Long COVID. The authors explain how ME/CFS researchers have developed reliable ways to diagnose the illness, define symptoms, and measure severity—lessons that can help Long COVID researchers do the same. By learning from ME/CFS experience, Long COVID researchers may be able to diagnose patients earlier, understand what causes the illness, and find treatments that actually work.
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Thematic groupings by clinical question or research area.
PET imaging and other studies providing evidence for brain inflammation in ME/CFS.
NeurologyMetabolomics and mitochondrial function studies revealing energy metabolism disruption.
MetabolismStudies identifying potential biological markers for ME/CFS diagnosis and stratification.
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