More to show dsmc would not recommend end point change etc
2.3. Will a DMC Help Assure the Scientific Validity of the Trial?
A third consideration in the decision of whether to have a DMC for a trial is whether a DMC can help assure scientific validity (and perception of such) of the trial. Trials of any appreciable duration can be affected by changes over time in the understanding of the disease, the affected population, and the standard treatment used outside the trial. These external changes may prompt an interest in modifying some aspects of the trial as it progresses. When a DMC is the only group reviewing unblinded interim data, trial organizers faced with compelling new information external to the trial may consider making changes in the ongoing trial without raising concerns that such changes might have been at least partly motivated by knowledge of the interim data and thereby endanger trial integrity. Sometimes accumulating data from within the trial (e.g., overall event rates) may suggest the need for modifications. Recommendations to change the inclusion criteria, the trial endpoints, or the size of the trial are best made by those without knowledge of the accumulating data (with the exception of changes the DMC might recommend on the basis of emerging safety concerns, as discussed in Section 4.4.1.2). When the trial organizers are the ones reviewing the interim data, their awareness of interim comparative results cannot help but affect their determination as to whether such changes should be made. Changes made in such a setting would inevitably impair the credibility of the study results. This problem will be addressed more fully in
