: 183 People with CFS have decreased scores on the SF-36 quality-of-life questionnaire, especially in the sub scales on vitality, physical functioning, general health, physical role, and social functioning; however, the sub scales for "role emotional" and mental health in CFS patients were consistent with or not substantially lower than healthy controls. Cognitive functioning
Cognitive dysfunction is one of the more disabling aspects of CFS due to its negative impact on occupational and social functioning. Fifty to eighty percent of persons with CFS are estimated to have serious problems with cognition. Cognitive symptoms are mainly due to deficits in attention, memory, and reaction time. Measured cognitive abilities are found to be below projected normal values and likely to affect day-to-day activities; for example, increases in common mistakes, forgetting scheduled tasks, or having difficulty responding when spoken to are observed.Simple and complex information-processing speed and functions entailing working memory over long time periods are moderately to extensively impaired. These deficits are generally consistent with the patients perceptions. Perceptual abilities, motor speed, language, reasoning, and intelligence do not appear to be significantly altered. When poorer health status was reported, a persons perception of their cognitive problems was frequently greater. Better physical functioning in people with CFS is associated with less visuoperceptual difficulty and fewer language-processing complaints.Inconsistencies of subjective and observed values of cognitive dysfunction reported across multiple studies are likely caused by a number of factors.
The PACE trial generated much criticism due to the broad Oxford criteria patient selection, the standards of outcome effectiveness were lowered during the study and that re-analysis of the data did not support the magnitude of improvements initially reported.Unlike pacing, APT is based on the cognitive behavioral model  of chronic fatigue syndrome and involves increasing activity levels, which it states may temporarily increase symptoms. In APT, the patient first establishes a baseline level of activity, which can be carried out consistently without any post-exertional malaise ("crashes"). APT states that persons should plan to increase their activity, as able. However, APT also requires patients to restrict their activity level to only 70% of what they feel able to do, while also warning against too much rest. This has been described as contradictory, and Jason states that in comparison with pacing, this 70% limit restricts the activities that patients are capable of and results in a lower level of functioning. Jason and Goudsmit, who first described pacing and the energy envelope theory for CFS, have both criticized APT for being inconsistent with the principles of pacing and highlighted significant differences. APT was promoted by Action for ME, the patient charity involved in the PACE trial, until 2019. Rintatolimod
Rintatolimod is a double-stranded RNA drug developed to modulate an antiviral immune reaction through activation of toll-like receptor 3. In several clinical trials of CFS, the treatment has shown a reduction in symptoms, but improvements were not sustained after discontinuation.