Posts
Thanks to Tom for another well-researched and well-thought-out discussion.
I went to send a letter to the editor in reply to the following article but
found the journal didn't accept take letters to the editor:
Implementing cognitive behavioral therapy for chronic fatigue
syndrome in a mental health center: A benchmarking evaluation.
Journal: J Consult Clin Psychol. 2008 Feb;76(1):163-71.
Authors: Scheeres K, Wensing M, Knoop H, Bleijenberg G
There were three main points:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1) As far as I can calculate, if one performs hypothesis testing, one finds
that the values obtained in the MHC are statistically different from the
research studies they compare them to, but they give the opposite impression
in the text (using different language)!!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Results: One-hundred forty-three CFS patients were referred to the MHC, of
whom 112 started
treatment. The implementation was largely successful, but a weak point was
the fact that 32% of all
referred patients dropped out shortly after or even before starting
treatment.
***Treatment effect sizes were in the range of those found in the benchmark
studies.***
Conclusions: CBT for CFS can successfully be implemented in an MHC.
Treatment results were acceptable, but the relatively large early dropout of
patients needs attention."
[..]
Results
[..]
"Comparison of treatment effects.
The noncontrolled effect sizes of the implementation study and the benchmark
studies are
given in Table 4 and in Figures 1 and 2. The mean pre-post
treatment effect size of the four benchmark studies for fatigue was
{1.02 (Sharpe et al., 1996) + 2.05 (Deale et al., 1997) + [3 * 1.25
(Prins et al., 2001)] + 1.83 (Stulemeijer et al., 2005)} / 6 = 1.44
(95% confidence interval [CI] = 0.97, 1.89). This is somewhat
higher than the effect size of fatigue in the MHC, which was 1.12
(95% CI + 0.85, 1.38). For physical functioning, the mean pre-
post treatment effect size of the benchmark studies was {1.93
(Deale et al., 1997) = [3 * 0.71 (Prins et al., 2001)] + 1.19
(Stulemeijer et al., 2005)} / 5 = 1.04 (95% CI = 0.63, 1.44). This
is again somewhat higher than the effect size at the MHC for
physical functioning, which was 0.64 (95% CI = 0.38, 0.89)."
[..]
Discussion
[..]
"***The results of the present study contradict the results of
Quarmby et al.'s (2006), who found a discrepancy in treatment
effect between their RCT and clinical results***. However, those
effect differences might be explained by the fact that their RCT
was extremely effective, which was the result of including only
one specialized therapist who was very experienced with CFS."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2) One didn't have to be that well to be considered recovered
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The recovery rate was analyzed by calculating
the percentage of patients clinically significantly improved.
Patients were defined as clinically significantly improved at posttreatment
if they had a reliable change index + 1.96 on the CIS-20
Fatigue Severity subscale, a Fatigue Severity score <= 35, and a
Rand-36 Physical Functioning score >= 65 (Vercoulen et al., 1999)."
I'm appending my comment on this from the related paper.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3) (less important) The Prins 2001 study is described as having used the CDC
'94 criteria (even though the symptom criteria weren't used i.e. the
patients weren't required to have 4 out of the 8 symptoms). Gis Bleijenberg
was involved in both studies and is well aware of what the CDC criteria
involve as he was on the review panel the CDC put together to re-assess the
criteria
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Prins et al. (2001)
Inclusion criteria:
CDC criteria for CFS
Cognitive behaviour therapy for chronic fatigue syndrome: a multicentre
randomised controlled trial.
Prins JB, Bleijenberg G, Bazelmans E, Elving LD, de Boo TM, Severens JL, van
der Wilt GJ, Spinhoven P, van der Meer JW.
Department of Medical Psychology, University Medical Centre, Nijmegen, The
Netherlands. j.prins@cksmps.azn.nl
~~~~~~~~~~~~~~~~~
Bye,
Tom Kindlon
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Thresholds for recovery were set very very "low" (perhaps the bottom
percentile and 5th lowest percentiles of the healthy adult population on the
two scales used)
Tom Kindlon (4 October 2008) Irish ME/CFS Association - for Information,
Support & Research
The thresholds for recovery seem very very low:
"Patients were defined as being CSI at post treatment if they had a reliable
change index > 1.96 on the CIS fatigue severity subscale [22], a fatigue
severity score <= 35 and a Rand-36 physical functioning score > = 65".
Many of the patients already likely had a "physical functioning score >=65"
given the mean (SD) values before treatment were: "Physical impairment (Rand
36) 54.0(23.4)"
And the threshold for recovery was only 0.47 SDs above the initial mean
score.
I am aware of the questions on the SF-36 PF subscale (scores can range from
0 to 100 with the higher the score, the better their "physical
functionaling") and I don't believe most healthy adults would believe
scoring 65 on the SF-36 PF scale would mean they were recovered.
As a study[1], that was co-written by one of the authors of this study (Gijs
Bleijenberg), pointed out, a community study found that "healthy adults
without a chronic condition" had "a mean score of 93.1 (SD 11.7)." The
authors of that study[1] pointed out they did not know the exact
distribution of the SF-36 subscales - they just made the assumption that the
mean - 1SD would represent a threshold for the 85th percentile and rounded
this figure to 80.
The threshold in the current study is 65. That is 2.4 SDs below the healthy
population's mean score. If the same assumptions were made (i.e. that the
curve was normally distributed), this would represent the bottom percentile!
For the CIS fatigue severity subscale (where the possible scores are 8-56
with the higher the score, the greater the fatigue), that same study that
Gijs Bleijenberg co-wrote[2] used (to calculate thresholds i.e. from another
study) a "normal group of 53 healthy adults with a mean age of 37.1 (SD
11.5)" who had "a mean score on the CIS-fatigue of 17.3 (SD 10.1)."[3]
The ages of those healthy adults are similar to the ages of the CFS patients
in this study: Mean (SD) 38.1 (10.2).
In that study[1], they estimated that the 85th percentile (mean+1SD) would
be 27 (due to rounding). This study uses 35 or the mean + 1.7525SD or the
95th percentile.
Put another way, patients in this study could be considered recovered if
they scored in the bottom percentile on the physical functioning subscale
(of the SF-36) and in the 5th lowest percentile on the CIS-fatigue scale!
Tom Kindlon
[1] Knoop H, Bleijenberg G, Gielissen MF, van der Meer JW, White PD. Is a
full recovery possible after cognitive behavioural therapy for chronic
fatigue syndrome? Psychother Psychosom. 2007;76(3):171-6.
[2] Aaronson NK, Muller M, Cohen PD, Essink-Bot ML, Fekkes M, Sanderman R,
Sprangers MA, te Velde A, Verrips E: Translation, validation, and norming of
the Dutch language version of the SF-36 Health Survey in community and
chronic disease population. J Clin Epidemiol 1998; 51: 1055-1068.
[3] Vercoulen JHMM, Alberts M, Bleijenberg G: De Checklist Individual
Strength (CIS) (The Checklist Individual Strength). Gedragstherapie
(Behavioural Therapy) 1999; 32: 642-649.
found the journal didn't accept take letters to the editor:
Implementing cognitive behavioral therapy for chronic fatigue
syndrome in a mental health center: A benchmarking evaluation.
Journal: J Consult Clin Psychol. 2008 Feb;76(1):163-71.
Authors: Scheeres K, Wensing M, Knoop H, Bleijenberg G
There were three main points:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1) As far as I can calculate, if one performs hypothesis testing, one finds
that the values obtained in the MHC are statistically different from the
research studies they compare them to, but they give the opposite impression
in the text (using different language)!!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Results: One-hundred forty-three CFS patients were referred to the MHC, of
whom 112 started
treatment. The implementation was largely successful, but a weak point was
the fact that 32% of all
referred patients dropped out shortly after or even before starting
treatment.
***Treatment effect sizes were in the range of those found in the benchmark
studies.***
Conclusions: CBT for CFS can successfully be implemented in an MHC.
Treatment results were acceptable, but the relatively large early dropout of
patients needs attention."
[..]
Results
[..]
"Comparison of treatment effects.
The noncontrolled effect sizes of the implementation study and the benchmark
studies are
given in Table 4 and in Figures 1 and 2. The mean pre-post
treatment effect size of the four benchmark studies for fatigue was
{1.02 (Sharpe et al., 1996) + 2.05 (Deale et al., 1997) + [3 * 1.25
(Prins et al., 2001)] + 1.83 (Stulemeijer et al., 2005)} / 6 = 1.44
(95% confidence interval [CI] = 0.97, 1.89). This is somewhat
higher than the effect size of fatigue in the MHC, which was 1.12
(95% CI + 0.85, 1.38). For physical functioning, the mean pre-
post treatment effect size of the benchmark studies was {1.93
(Deale et al., 1997) = [3 * 0.71 (Prins et al., 2001)] + 1.19
(Stulemeijer et al., 2005)} / 5 = 1.04 (95% CI = 0.63, 1.44). This
is again somewhat higher than the effect size at the MHC for
physical functioning, which was 0.64 (95% CI = 0.38, 0.89)."
[..]
Discussion
[..]
"***The results of the present study contradict the results of
Quarmby et al.'s (2006), who found a discrepancy in treatment
effect between their RCT and clinical results***. However, those
effect differences might be explained by the fact that their RCT
was extremely effective, which was the result of including only
one specialized therapist who was very experienced with CFS."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2) One didn't have to be that well to be considered recovered
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The recovery rate was analyzed by calculating
the percentage of patients clinically significantly improved.
Patients were defined as clinically significantly improved at posttreatment
if they had a reliable change index + 1.96 on the CIS-20
Fatigue Severity subscale, a Fatigue Severity score <= 35, and a
Rand-36 Physical Functioning score >= 65 (Vercoulen et al., 1999)."
I'm appending my comment on this from the related paper.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3) (less important) The Prins 2001 study is described as having used the CDC
'94 criteria (even though the symptom criteria weren't used i.e. the
patients weren't required to have 4 out of the 8 symptoms). Gis Bleijenberg
was involved in both studies and is well aware of what the CDC criteria
involve as he was on the review panel the CDC put together to re-assess the
criteria
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Prins et al. (2001)
Inclusion criteria:
CDC criteria for CFS
Cognitive behaviour therapy for chronic fatigue syndrome: a multicentre
randomised controlled trial.
Prins JB, Bleijenberg G, Bazelmans E, Elving LD, de Boo TM, Severens JL, van
der Wilt GJ, Spinhoven P, van der Meer JW.
Department of Medical Psychology, University Medical Centre, Nijmegen, The
Netherlands. j.prins@cksmps.azn.nl
~~~~~~~~~~~~~~~~~
Bye,
Tom Kindlon
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Thresholds for recovery were set very very "low" (perhaps the bottom
percentile and 5th lowest percentiles of the healthy adult population on the
two scales used)
Tom Kindlon (4 October 2008) Irish ME/CFS Association - for Information,
Support & Research
The thresholds for recovery seem very very low:
"Patients were defined as being CSI at post treatment if they had a reliable
change index > 1.96 on the CIS fatigue severity subscale [22], a fatigue
severity score <= 35 and a Rand-36 physical functioning score > = 65".
Many of the patients already likely had a "physical functioning score >=65"
given the mean (SD) values before treatment were: "Physical impairment (Rand
36) 54.0(23.4)"
And the threshold for recovery was only 0.47 SDs above the initial mean
score.
I am aware of the questions on the SF-36 PF subscale (scores can range from
0 to 100 with the higher the score, the better their "physical
functionaling") and I don't believe most healthy adults would believe
scoring 65 on the SF-36 PF scale would mean they were recovered.
As a study[1], that was co-written by one of the authors of this study (Gijs
Bleijenberg), pointed out, a community study found that "healthy adults
without a chronic condition" had "a mean score of 93.1 (SD 11.7)." The
authors of that study[1] pointed out they did not know the exact
distribution of the SF-36 subscales - they just made the assumption that the
mean - 1SD would represent a threshold for the 85th percentile and rounded
this figure to 80.
The threshold in the current study is 65. That is 2.4 SDs below the healthy
population's mean score. If the same assumptions were made (i.e. that the
curve was normally distributed), this would represent the bottom percentile!
For the CIS fatigue severity subscale (where the possible scores are 8-56
with the higher the score, the greater the fatigue), that same study that
Gijs Bleijenberg co-wrote[2] used (to calculate thresholds i.e. from another
study) a "normal group of 53 healthy adults with a mean age of 37.1 (SD
11.5)" who had "a mean score on the CIS-fatigue of 17.3 (SD 10.1)."[3]
The ages of those healthy adults are similar to the ages of the CFS patients
in this study: Mean (SD) 38.1 (10.2).
In that study[1], they estimated that the 85th percentile (mean+1SD) would
be 27 (due to rounding). This study uses 35 or the mean + 1.7525SD or the
95th percentile.
Put another way, patients in this study could be considered recovered if
they scored in the bottom percentile on the physical functioning subscale
(of the SF-36) and in the 5th lowest percentile on the CIS-fatigue scale!
Tom Kindlon
[1] Knoop H, Bleijenberg G, Gielissen MF, van der Meer JW, White PD. Is a
full recovery possible after cognitive behavioural therapy for chronic
fatigue syndrome? Psychother Psychosom. 2007;76(3):171-6.
[2] Aaronson NK, Muller M, Cohen PD, Essink-Bot ML, Fekkes M, Sanderman R,
Sprangers MA, te Velde A, Verrips E: Translation, validation, and norming of
the Dutch language version of the SF-36 Health Survey in community and
chronic disease population. J Clin Epidemiol 1998; 51: 1055-1068.
[3] Vercoulen JHMM, Alberts M, Bleijenberg G: De Checklist Individual
Strength (CIS) (The Checklist Individual Strength). Gedragstherapie
(Behavioural Therapy) 1999; 32: 642-649.
