Very good BMJ rapid response to the FINE Trial Paper
[sb: I couldn't find this posted anywhere. Well done Sam.]
Rosie Cox <RosieCox@ntlworld.com> [via Co-Cure Moderators <co-cure-mod@listserv.nodak.edu>] to
CO-CURE May 6
http://www.bmj.com/cgi/eletters/340/apr22_3/c1777
Competing interests: None declared
A valedictory dispatch from the Psychosocial School? 5 May 2010
Sam Carter,
ME Patient
Does Pragmatic Rehabilitation (PR) reduce the "fatigue" experienced by
people diagnosed with CFS/ME according to the Oxford criteria (1)? Wearden
et al report in the Abstract of their paper that after 20 weeks of PR
participants had "significantly improved fatigue" and, in their linked
editorial, Moss-Morris and Hamilton state that participants receiving PR
were "significantly less fatigued". However, in the body of the text,
Wearden et al describe the improvement as being "small" and "clinically
modest". Thus, in the same journal, we find that the effect of PR on fatigue
is simultaneously "significant" and "small".
The effect cannot be both large and small, so which interpretation best
matches the data?
A participant's fatigue was measured using the 11 item Chalder Fatigue Scale
(ChFS) "scored dichotomously on a four point scale (0, 0, 1, or 1)". The
ChFS has been criticised because it "has a low ceiling, so patients with
maximal scores at baseline will not be able to record an exacerbation after
treatment." (2) The maximum one can score on the ChFS is 11, after which it
cannot detect further deterioration. It can be seen from the published data
that participants receiving PR had a mean baseline ChFS score of 10.49 from
which it can be calculated that between 47 and 88 of the 95 participants
started therapy with a ChFS score of 11. Therefore, at least half of the
participants could not report that PR had worsened their fatigue, even if
such were the case. PR involves graded exercise so one would expect this
therapy more than "supportive listening" or normal GP treatment
(unspecified) to exacerbate fatigue but, had this occurred, the ChFS could
not have detected it. Thus, the inability of the ChFS to measure
deterioration in this patient cohort biases the trial in favour of finding
"improvements" in fatigue and, in particular, favours PR because
exercise-induced relapses cannot be recorded.
A genuine improvement in fatigue would, axiomatically, lead to increased
physical capacity, but no statistically significant change in physical
function was found in the PR group and, in fact, participants randomised to
the control group (GP treatment as usual) experienced greater improvement in
physical function.
Thus the conclusion that PR led to a real improvement in participants'
fatigue must be interpreted with caution.
The authors suggest that "treatment effects may have been enhanced had we
been able to provide post-treatment booster sessions." However, it is
instructive to note that the mean ChFS score fell from 10.49 at baseline to
8.39 after 20 weeks of therapy where, according to the text, "total scores
of four or more on the fatigue scale designate clinically significant levels
of fatigue." Therefore, even if extra sessions had trebled the efficacy of
Pragmatic Rehabilitation, participants would still have "clinically
significant levels of fatigue".
Notwithstanding, Wearden et al comment: "it is likely that our trial gives
an accurate indication of the effectiveness of nurse delivered pragmatic
rehabilitation and supportive listening for CFS/ME in primary care." Indeed
it does: the data provide strong evidence that the anxiety and
deconditioning model of CFS/ME on which the trial is predicated is either
wrong or, at best, incomplete. These results are immensely important because
they demonstrate that if a cure for CFS/ME is to be found, one must look
beyond the psycho-behavioural paradigm.
(1) Sharpe MC, Archard LC, Banatvala JE, et al. (February 1991). "A
report--chronic fatigue syndrome: guidelines for research". J R Soc Med 84
(2): 118-21
(2)
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