- Why a 3-year cutoff?
Would the difference between early cases, late cases and controls still be statistically significant if another arbitrary cutoff (e.g. 2, 4 or 5 years) was choosen?Competing Interests: None declared.
- RE: a need for validated data to avoid false hope for patients suffering chronic fatigue syndrome
We read with interest the article by Hornig et al published in the Journal. Although authors should be commended for conducting such important study on patients suffering chronic fatigue syndrome (CFS), we suggest that the conclusions of their paper (“the presence of a specific immune profile early in the course of CFS has important implications for the diagnostic process”) may be strongly tempered.Show More
Indeed, in our opinion, numerous methodological issues prevent from translating reported results into routine practice to improve the diagnosis of CFS. First, we do not agree with the choice not to use adjustment for multiple comparisons although CFS patients (or cases) were compared to healthy controls for no less than 51 parameters. Indeed, observed differences yielded only p value close to the statistical significance cutoff, and one can wonder if applying multiple comparisons adjustment such as the Benjamini and Hochberg method (used by authors elsewhere in the manuscript) would not have led to the absence of any significant differences. Second, the differences observed between cases (CFS) and controls were so “biologically” small (ie, IL-6 mean levels were 10.2 pg/ml in cases versus 10.9 pg/ml in controls) that authors focused on the differences observed instead with 2 subsets of cases: short versus long duration CFS. Of importance, these differences could have been at least partially related to major differences in the characteristics of patients (short duration CFS...Competing Interests: None declared.
- Distinct plasma immune signatures in ME/CFS are present early in the course of illness
Cytokine alterations are more strongly correlated with illness duration than with measures of illness severity.Permalink: