Julie
Conducting research on physical therapy interventions as you describe is
indeed difficult. I agree with the statements about the importance of
recording clearly the actual interventions and their dosage (something
rarely well reported). While some suggest a specific dosage this is not
consistent with the approach of physical therapy to customize to each
patient the level of needed exercise/manual intervention and progress
as tolerated. I suggest you define clear rules about how the intensity
is set and progressed and a set of parameters which all therapists use
(and train them to promote fidelity). Also RCTs would have to be
extremely large to detect small differences so insure that the treatment
approaches have sufficient difference. Too often I have seen trials
comparing a home program of 1 visit to clinic treatment of 3 visits
only to find no difference. Two designs that you may wish to explore
include the factorial design where you could explore the effects of
different factors and their combination OR the expertise-based design if
you think practitioner skills/preferences are an important issue.
Joy macdermid
McMaster university
-----Original Message-----
From: Evidence based health (EBH)
[mailto:[log in to unmask]] On Behalf Of Caroline
Boulind
Sent: January-11-10 2:20 PM
To: [log in to unmask]
Subject: Re: A query from a colleague
Julie,
There is quite a lot of literature about difficulties with surgical
research and studies into non-pharmacological interventions, relating to
the things that you are talking about. A quick search for methodology in
surgical trials should come up with them. Isabelle Boutron has written
about this subject, so you could search with her name. There was also a
series of 3 articles in the Lancet last year. They are discussing
problems in surgical trials, but a lot of the issues are the same as
Simon mentioned. I have the reference for the second in the series. The
Lancet, Volume 374, Issue 9695, Pages 1097 - 1104, 26 September 2009.
I hope this helps,
Caroline
Dr. Caroline Boulind
Clinical Research Fellow
01935 384559
>>> Paul Glasziou <[log in to unmask]> 11/01/2010 17:58 >>>
Dear Julie
Steve's distinction of phase is a good one. And I suspect that you are
in the "proof of concept" phase with your self-learning exercises. So I
think it would be better to try to set some standards for the control.
If you use the more libreral approach, then it would be important to
document (at least briefly) what was actually done. Many trials,
particularly non-drug ones*, fail to sufficiently describe what was done
and we are left in the dark.
Best wishes
Paul Glasziou
* Glasziou P, Meats E, Heneghan C, Shepperd S. What is missing from
treatment descriptions in trials and reviews? BMJ 2008;336:1472-74
Steve Simon, P.Mean Consulting wrote:
> Julie Nowak wrote:
>
>> I work currently as a french physiotherapist in a pain center to
>> conduct a study on chronic neck pain. We had already made a draft
>> study on this subject but the lack of patient was not possible to
>> draw reliable conclusions. So we begin the study and hoped to have
>> the advice of your organization to conduct a study reliable and
>> relevant.
>
>> This study focuses on self-management of patients with chronic neck
>> pain. Patients were divided into two groups, a control group of
>> liberal conventional physiotherapy for 3 months and the group with
>> physiotherapy liberal more self-learning exercises on the neck. An
>> initial assessment is conducted by a physiotherapist after inclusion
>> in the protocol by the medical center pain. We test the amplitude,
>> strength, kinesthetic , pain, muscle tension, etc.. Then we teach to
>> the patient self-exercises like active mobilization, stretching,
>> muscle strengthening, and friction massage to relieve pain.
>>
>> After 3 months the groups are reversed, so as not to delease a group
>> and see if it is better to do self-exercise after liberal physical
>> therapy or at the same time. The study will be made during 1 year.
>>
>> Two problems are presents with this Protocol:
>>
>> The conventional physical therapy is vast and varied, many methods
>> exist and it seems difficult to compare different physiotherapists
>> liberals among them, each method is unique. I don't know how to do to
>> have homogen liberal traitment.
>>
>> The 2nd question is in the choice of stretching, in effect giving
>> stretch identical to each patient can not seem to be the most
>> effective method, but adjust stretch learning to each patient makes
>> it difficult to compare results.
>
> Many medical interventions rely strongly on the skill and experience
of
> the practitioner. Surgery trials are an excellent example. This
> introduces some heterogeneity into the sampling process. Heterogeneity
> adds "noise" to the data but if you are lucky it should not produce
any
> biases. So I would encourage you to select as large a sample size as
you
> can, report the heterogeneity as a limitation of the study, and hope
for
> the best. Any attempt to excessively standardize either the control
> group or the treatment group will produce an artificial result that
does
> not represent how medicine is practiced in the real world.
>
> You can view this as a trade-off between internal validity and
external
> validity. A rigorously defined intervention and control group makes
the
> statistical comparison good (internally validity) but makes it harder
to
> extrapolate to a real world setting (external validity). As a general
> rule, studies of new and emerging interventions should stress internal
> validity (proof of concept trials) and studies of interventions that
are
> already well established should stress external validity (pragmatic
> trials). I suspect that you are comparing interventions that are
already
> well entrenched, but that is pure speculation on my part.
>
> Bonne chance avec votre recherche.
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