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Gathering Key Data
on All Subjects
Intention-to-treat
analyses, the stringent requirement that data is analyzed from
all patients who have been randomized into an RCT raises -- whether
or not they completed the trial -- some special issues in clinical
trials of TMD treatment.
Obviously, if patients
drop out of an RCT after being randomized but before all follow
up data collection is completed, the final sample sizes will be
smaller and the possibility arises that statistical analyses will
be less valid. Some strategies to reduce loss to follow up or
missing data on critical measures include gathering data at least
on the primary outcome measures over time, even if the patient
will not submit to full batteries of repeated questionnaires.
Thus, it is recommended
that investigators obtain permission from TMD patients at the
onset of RCTs, before randomization, to gather at least a small
amount of data even if the patient doesn't allow full data accumulation.
If the primary outcome measure is pain, for instance, then attempts
are made to insure that VAS pain levels (and possibly one or two
additional, critical variables) can be gathered at each data collection
point included in the RCT study design. Such permission is usually
more reliably obtained at the onset of the RCT rather than later
in the trial when the patient drops out and may become lost, not
only to follow up but to any possibility of contact.
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