Longitudinal change in chronic fatigue syndrome: what home-based 
assessments reveal.

J Behav Med. 2008 Dec 20. [Epub ahead of print]

Friedberg F, Sohl SJ.

Department of Psychiatry and Behavioral Science Putnam 
Hall, South Campus, Stony Brook University, Stony Brook, NY, 
11794-8790, USA, fred.friedberg@stonybrook.edu.

NLM Citation: PMID: 19101789


The purpose of this 2-year prospective study was to compare standard 
self-report and ecologically-based outcome measures in patients with 
chronic fatigue syndrome (CFS).

Standard measures assessed physical function, fatigue impact, 
psychological variables, and global impression of change ratings. 
Ecological measures included actigraphy, a structured activity 
record, and an electronic fatigue/energy diary.

Results for this high functioning sample (N = 75) revealed that 
self-report global improvement was significantly associated with 
lower momentary fatigue and fatigue impact, and a higher frequency of 
standing up (at home), but not with actigraphy or psychological 
variables. However, actigraphy change was significantly correlated 
with change in self-report physical function. At follow-up, only a 
small minority (<20%) scored in the healthy adult range for fatigue 
impact and physical function.

The findings suggest that home-based measures of symptom severity and 
physical functioning may provide evidence of change (or lack of 
change) that is important for interpreting standard self-report 
outcomes in CFS.