Publication trends in chronic fatigue syndrome: Comparisons with fibromyalgia and fatigue: 1995-2004

Objective: In order to identify publishing patterns in chronic fatigue syndrome (CFS), we compared the annual number of peer review articles for CFS, fibromyalgia (FM), and non-CFS fatigue over a recent decade (1995-2004). Method: Citations were drawn from Ovid/Medline, PsychInfo, and the Journal of Chronic Fatigue Syndrome for peer review articles focusing on CFS, FM, and fatigue for each year of the decade ending in 2004. Statistics included chi-square, tests for differences in proportions, and regression-based curve estimation. Results: The frequency of CFS peer review articles did not significantly change from the first half to the second half of the decade (1995-2004). By comparison, the output of both FM and fatigue articles significantly increased (P<.0001). A quadratic model (inverted U shape; P<.02) best fit the data for CFS annual publication frequency. By comparison, exponential models best fit the data for both FM (P<.0001) and fatigue (P<.0001) citations. The highest percentage of citations (15-16%) for both CFS and FM fell within the domains of diagnosis, physiopathology, and psychology. For fatigue, almost one third (31.4%) of the citations were focused on etiology, while psychology (11.5%) and physiopathology (10.4%) articles were the next most cited. Based on first-author affiliation, CFS articles were most likely to originate in the United States (37.7%), England (31.4%), and the Netherlands (4.9%). Conclusion: The output of CFS peer review articles has not increased over the past decade, while the number of FM and fatigue articles has increased substantially.