Strengths and weaknesses
We faced an important number of lost in follow-up patients. But as these
drop out patients presented the same characteristics as the non-drop out
patients, it limits the bias they could cause.
We did not reach the estimated number of patients to include. However,
despite these small samples, we still found a significant difference in
the per protocol analysis.
We proceeded to sensitivity analysis that gave us an exhaustive analysis
of the results and still showed a difference, even in the “worst case
scenario”, confirming the positive effect of the interventions.
The same pharmacist performed all the intervention. This gave a better
reproducibility of the interviews during the study, but it reduces the
reproducibility of potential further studies.
The solid methodology through the physician-blind, the effective
randomization and the presence of a control group reinforced the value
of these results. However, even if patients of the control did not get a
pharmaceutical intervention, it should be noted that they had an
inclusion interview with the pharmacist, at the moment of the inclusion.
Even if this interview was only intended to collect the necessary data
form the patients, the latter often asked questions about their
treatments. Thus, the inclusion interview in the control group may have
provided information similar to the pharmaceutical intervention, in a
lesser extent. Though, if this could represent a bias, it would act as
increasing the proportion of patients reacing the therapeutic objectives
in the control group which would be defavorable to our hypothesis and
reinforces the significance of our findings.