Baseline data is
collected after consent is obtained. In some studies, the
population from which the study sample is recruited has a
high prevalence of fatigue and patients can be screened with
a brief verbal item about fatigue to determine eligibility.
Eligible patients can then be recruited directly, sign consent,
and be given the baseline assessment questionnaire packet.
In other studies, particularly those involving treatment-related
fatigue, the protocol may need to stipulate repeated verbal
screening of cases to identify those who become eligible as
fatigue develops. Patients who develop fatigue are asked to
provide consent and then complete baseline data.
In studies that
randomly assign treatments, randomization typically occurs
prior to baseline data collection. Following data collection,
the appropriate study interventions are implemented. The protocol
must be very specific in defining this process. The intervention
may require weeks and involve titration (gradual dose adjustment,
increasing exercise, or other). Repeated data collection should
again be timed to provide relevant information about time
course or accruing effects, as well as information about maximum
There has been
very little experience in the practical administration of
controlled drug trials for fatigue. In the absence of this
experience, it is prudent to adopt lessons gained during many
decades of controlled
trials of analgesic drugs. These lessons involve
design considerations (parallel group vs. crossover); use
of placebo, active placebo, and active controls; and other
approaches to ensure study sensitivity.