Criteria for an ME/CFS diagnosis

While a number of criteria for diagnosing ME/CFS have been formulated over the years, the 2011 International Consensus Criteria (ICC) is the most current criteria created by an international group of ME/CFS experts.

Source:’s blog post THE INTERNATIONAL CONSENSUS CRITERIA What is it? Do I fit the criteria?

Do I fit the International Consensus Criteria?

Questionnaire for patients over age 18

Disclaimer: This questionnaire does not replace the full International Consensus Criteria (ICC) document or the primer. It is based on the symptoms of the criteria and should not be used as a substitute for medical advice from a licensed medical professional. This document is for informational purposes. Consult a physician experienced in diagnosing ME. It is important to evaluate for other diseases before assigning a diagnosis of ME (ICD code G93.3).

According to the ICC, a six-month waiting period (a common prerequisite for an ME diagnosis) is NOT required for diagnosis of ME. Removing the waiting period is very important so ME patients can be advised to get complete rest as soon as possible in order to get the best possibility of improved health.


According to the ICC, in order to be diagnosed with ME, you must have Post Exertional Neuroimmune Exhaustion (PENE).

PENE is the physical inability to produce sufficient energy on demand.

The following are signs you have PENE:

  1. Marked, rapid physical and/or cognitive fatigability in response to exertion, which may be minimal such as activities of daily living or simple mental tasks, can be debilitating and cause a relapse.
  2. Post-exertional symptom exacerbation: such as acute flu-like symptoms, pain and worsening of other symptoms.
  3. Post-exertional exhaustion: may occur immediately after activity or be delayed by hours or days
  4. Recovery period is prolonged, usually taking 24 hours or longer.  A relapse can last days, weeks or longer
  5. Low threshold of physical and mental fatigability (lack of stamina) results in a substantial reduction in pre-illness activity level.

Symptom severity must result in a significant reduction in pre-illness activity levels.

If you aren’t sure if you have PENE, watching the following video explaining an abnormal physiological response to exertion and the 2 day test may help you answer the question. The 2-day Cardio Pulmonary Exercise Test is a 2 day CPET specifically designed to look for inability to repeat physical activity two days in a row.

Do you have PENE?  ___ Yes   ___No

If YES, proceed to the next section.

If NO, stop quiz. You do not fit the International Consensus Criteria.


Check off the ones that apply to you.

Neurocognitive Impairments

 ____  Difficulty processing information: slowed thought, impaired concentration such as confusion, disorientation, cognitive overload, difficulty with making decisions, slowed speech, acquired or exertional dyslexia

 ____  Short-term memory loss: difficulty remembering what one wanted to say, what one was saying, retrieving words, recalling information, poor working memory


 ____  Headaches: such as chronic, generalized headaches often involve aching of the eyes, behind the eyes or back of the head that may be associated with cervical muscle tension; migraine; tension headaches

 ____  Significant pain can be experienced in muscles, muscle-tendon junctions, joints, abdomen or chest. It is non inflammatory in nature and often migrates. In other words have generalized hyperalgesia (increased sensitivity to pain), widespread pain (may meet fibromyalgia criteria), myofascial (pertaining to a muscle and its sheath of connective tissue, or fascia) or radiating pain.

Sleep Disturbance

 ____  Disturbed sleep patterns: such as insomnia, prolonged sleep including naps, sleeping most of the day and being awake most of the night, frequent awakenings, waking much earlier than before illness onset, vivid dreams/nightmares

 ____  Unrefreshed sleep: awaken feeling exhausted regardless of duration of sleep, day-time sleepiness

 Neurosensory, perceptual and motor disturbances

 ____  Neurosensory and perception:  inability to focus vision, sensitivity to light, noise, vibration, odor, taste and touch; impaired depth perception

 ____  Motor:  muscle weakness, twitching, poor coordination, feeling unsteady on feet, ataxia (inability to coordinate muscle activity)

Did you check at least one box in at least three categories in section 2?  __ Yes    __ No

If YES, go to next question.

If NO, continue for possible atypical ME criteria.


Check off the areas that apply to you.

 ____  Flu-like symptoms may be recurrent or chronic and typically activate or worsen with exertion. Such as sore throat, sinusitis, cervical and/or axillary lymph nodes may enlarge or be tender

 ____  Susceptibility to viral infections with prolonged recovery periods

 ____  Gastro-intestinal tract: such as nausea, abdominal pain, bloating, irritable bowel syndrome

 ____  Genitourinary: such as urinary urgency or frequency, excessive urination at night

 ____  Sensitivities to food, medications, odors or chemicals

Did you check at least three boxes in section 3?     ___ Yes  ___ No

If YES, go to next question.

If NO, continue for possible atypical ME criteria.


Check off the ones that apply to you:

 ____  Cardiovascular: inability to tolerate an upright position – orthostatic intolerance, neurally mediated hypotension, postural orthostatic tachycardia syndrome, palpitations with or without cardiac arrhythmias, light-headedness/dizziness

 ____  Respiratory: air hunger, laboured breathing, fatigue of chest wall muscles

 ____  Loss of thermostatic stability: subnormal body temperature, marked diurnal fluctuations; sweating episodes, recurrent feelings of feverishness with or without low grade fever, cold extremities

 ____  Intolerance of extremes of temperature

Did you check at least one box in section 4?     ___Yes  ___ No

If NO, continue for possible atypical ME criteria.



If you have answered YES to each section, you fit the International Consensus Criteria for Myalgic Encephalomyelitis.

If you answered NO in section 2, 3, or 4, you may have atypical ME. Atypical myalgic encephalomyelitis​ meets criteria for PENE (section 1), but has a limit of two less than required of the remaining criterial symptoms. Pain or sleep disturbance may be absent in rare cases.

I think I have ME, what now?

It’s important to consult a doctor with experience in diagnosing and treating ME/CFS as soon as possible. We are building a list of medical practitioners in South Africa who are reported as being able to diagnose and treat ME/CFS.

Please help us to advocate for you by adding your name to our national registry. The purpose of the registry is for us to start gathering data about the number of South Africans suffering from ME/CFS and statistics on living circumstances, as well as to share information with you.

To join our online support group, please send an email to Please note that the support group is a ‘closed’ Facebook group, which means it can only be joined by invitation and the content can only be viewed by members of the group.