Table 1.

Inclusion and exclusion criteria

1) ≥ 18 years.
2) Able to speak, read, and write Dutch.
3) Able to use a computer and have access to Internet.
4) CFS diagnosis according to the CDC consensus criteria:	[1, 2]
5) Severe fatigue is assessed with the subscale fatigue severity of the Checklist Individual Strength (CIS). Severe fatigue is operationalized as scoring ≥ 35.	[23]
6) Disabilities; Disability is assessed with the total score of the Sickness Impact Profile (SIP8). Severe disability is operationalized as a total score ≥ 700 on the SIP8.	[27, 41]
7) Given written informed consent.
Exclusion criteria
1) Engaged in a legal procedure concerning disability-related financial benefits.
2) Participating in other CFS research.