How are they then chosen? What set of criteria are being used?
You might find it helpful to look at the last Report from the UK ME/CFS Biobank
The sample numbers, incidentally, have increased since then
Report:
http://www.meassociation.org.uk/wp-...ank-Report-Executive-Summary-Nov-14-final.pdf
Inclusion and Exclusion criteria are on pages 7 to 8:
Inclusion criteria
ME/CFS cases: informed consent, 18 to 60 years old, and clinical diagnosis of ME/CFS according to Canadian (1) or CDC-1994 (2) criteria. Compliance with study criteria was confirmed by a clinical member of the research team (doctor) after reviewing the results of a range of laboratory tests used to exclude alternative diagnoses.
Healthy controls: informed consent, 18 to 60 years old, no past or present fatiguing illnesses and/or other major morbidity such as cancer or coronary heart disease.
Exclusion criteria
Cases: Recent use (in the preceding 3 months) of drugs known to alter immune function (e.g. azathioprine, cyclosporine, methotrexate, steroids); anti-viral medications and vaccinations; history of acute and chronic infectious diseases such as hepatitis B and C, tuberculosis, HIV (but not herpes virus or other retrovirus infection); other severe illnesses and severe mood disorders. Pregnant women and those within 12 months post-partum and/or currently lactating are excluded.
Healthy controls: all of the above, in addition to the presence of any fatiguing illnesses and other conditions that would exclude a diagnosis of ME/CFS (in those with fatigue), present or past.
Potential participants were invited to join the study by their doctor (affiliated with a collaborating NHS site) or by ME/CFS Disease Register staff if the patient was enrolled in the ME/CFS Disease Register. The LSHTM research team provided invitation packs to the participating NHS sites, which posted them to the potential participants identified in the database search. The invitation pack included an invitation letter from the health service, information about the study (with separate information sheets for cases and controls), a “Symptoms Assessment” form for determining case definition compliance, a consent form, a refusal form, and a stamped self-addressed envelope.
Because people severely affected by ME/CFS (that is, bed- or home-bound) often do not, or cannot, visit NHS services, and are particularly under-represented in ME/CFS research, information sheets and invitation packs were sent to support groups in the Greater London area for identification of and distribution to interested individuals in this segment of the ME/CFS population. Unfortunately, those very severely affected by the disease would be unable to participate because of the need to complete a half-hour clinical assessment and to provide a blood sample. 8 | P a g e
Potential participants with ME/CFS were also asked to invite a friend to participate as a healthy control and so invitation packs were provided to them for this purpose. Additionally, information packs were made available at NHS sites and at LSHTM to supplement healthy control recruitment.
When the signed consent and “Symptoms Assessment” forms were received by the research team, they were reviewed by the clinical researcher to confirm compliance with the inclusion and exclusion criteria for cases and controls. All potential cases would have received a diagnosis of ME/CFS at some time in the past. The clinical staff then assessed the diagnosis of ME/CFS according to the study’s protocol, which requires compliance with the Canadian Consensus Criteria (1) and/or the CDC-1994 criteria (2). Cases meeting the former have been shown in most cases to also meet the latter criteria (4), and the former seems to characterise those who are most severely affected. Comprehensive phenotyping of patients at baseline also enabled categorisation of individuals according to other clinical criteria, such as the London (7) and International Consensus (8) criteria, although these definitions were not used to determine enrolment eligibility.
Once eligibility was established, the research team booked appointments for participants for clinical assessments and blood sample collection. Participants in the Greater London area with severe disease and/or mobility restrictions were seen at their homes. Consenting respondents ineligible according to the screening questionnaire were thanked by the research team and told that their ineligibility was based on the exclusionary criteria.
We have just put out an appeal for more people with severe ME/CFS and for some healthy controls:
http://www.meassociation.org.uk/201...lood-samples-to-be-stepped-up-21-august-2015/
This is the work that is being done with the US/NIH grant:
http://blogs.lshtm.ac.uk/news/2013/06/28/uk-mecfs-biobank-project-awarded-1-million-grant/
Dr Charles Shepherd
Chairman, UK ME/CFS Biobank Steering Group