Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Frequently Asked Questions

Why is the focus of the study on post-infectious ME/CFS patients?

People have symptoms of ME/CFS that arise from many potential causes. Focusing initially on a single potential cause will let the researchers better single out potential biological changes with ME/CFS. These results may then be applicable to the broader ME/CFS community and may be expanded in future research studies.

Why have recovered post-Lyme patients been included as controls?

Similar to post-infectious ME/CFS, the group has had exposure to a known infection, Lyme disease. Comparing ME/CFS to those who recovered from Lyme may help us understand the role infection and immune response plays in ME/CFS.

Will there be additional control groups?

Healthy volunteers will also serve as a "control group" for this study.

Why is the duration from onset for the PI-ME/CFS patients limited to 5 years?

Some of the body's responses to infection change with time. Focusing initially on a single time period will let researchers better single out potential biological changes. For this reason, we are limiting participation in this initial study to people who have had ME/CFS for at least 6 months but less than 5 years.

Will ME/CFS experts be involved in selecting patients to enroll?

People whose doctors have diagnosed ME/CFS will be eligible to enroll if they meet other eligibility requirements. Clinical experts will be confirming a diagnosis of post-infections ME/CFS to determine who can proceed to an exercise stress visit.

How does this study relate to the CDC in the Multi-site Clinical Assessment of CFS study

Those with ME/CFS currently seen in ME/CFS clinics supported by the CDC in the Multi-site Clinical Assessment of CFS study may also be eligible to participate in this study. (

How are the enrolled participants being evaluated for ME/CFS?

The study team will provide information from the initial study visit for ME/CFS participants to the adjudication committee. The adjudication committee will then review the data and medical records to determine if the participant with ME/CFS can proceed to the exercise stress visit.

Why is there an adjudication committee that determines which ME/CFS patients are eligible to participate in the exercise stress visit?

An adjudication process ensures fairness and uniformity in the selection process.

Who are members of the adjudication committee?

Committee members are recognized experts in ME/CFS. The initial members include: Lucinda Bateman, Andy Kogolnik, Tony Komaroff, Benjamin Natelson, and Daniel Peterson. The chair of the adjudication panel is the Principal Investigator, Dr. Avindra Nath (

Are diagnostic criteria going to be used in the adjudication process?

The adjudication committee will consider the 1994 Fukuda, 2003 Canadian Consensus criteria, and additional information collected during the initial study visit in the adjudication process.

When will the study start enrolling patients?

We anticipate that participants will start enrolling in fall 2016.

What is the role of the Lead Associate Investigator in the study?

The Lead Associate Investigator (LAI) assists Dr. Nath with the oversight of the day-to-day operations of the protocol. The LAI will work with the CDC, Multi-site Clinical Assessment of CFS study physicians, and the community to coordinate recruitment for the study. The LAI will assist in providing study information prior to enrollment and with the informed consent process when enrolling. The LAI will coordinate research participation with the participant’s medical providers. The LAI will coordinate the multidisciplinary experts collaborating in this complex study and will provide clinical management for the study participants while at the NIH Clinical Center.