Inherent difficulties include evidence gaps in available biomarker data, a paucity of robust assay methods, and the design of appropriate studies within the constraints of feasible trial operations, and finite resources.
Randomization tests consider all other possible rearrangements of the data for this patient, within the constraints of the trial design (Fig. 1B).
Because of constraints of the trial, unfortunately, we could not determine whether the platinum-based DSB-inducing regimen would have resulted in a similar improved outcome had it been conventionally dosed.
Given its lack of extensive clinical use outside the tight constraints of clinical trials, there are many unknowns, and routine use of the drug in patients outside of clinical trials will require careful postmarketing surveillance.
Observational studies such as this can thus provide useful and reliable information on treatment effects and can be used for preliminary hypothesis testing at a fraction of the cost and constraints of pivotal trials.
Some authors have attempted to align research design with TCM clinical practice within the constraints of a clinical trial [ 3, 4]; whereas many TCM clinical trials adopt a conventional research design [ 5].
To address this need for contextual understanding under the constraints of a clinical trial we adapted the cognitive mapping approach.
Oncologic principles would be abased, and the outcome of patients in the real world outside the tight control and constraints of a clinical trial would be compromised.
The adherence rates in this study are much higher than the rates previously reported in the literature (30%to70%0%),[ 5, 6] and may have been influenced by the constraints of the clinical trial in terms of attention and study participants.
Effectiveness studies can be difficult to conduct in that the design constraints of a randomized trial create a nonreal-world setting; therefore, frequently, effectiveness is assessed using cohort studies.
