“Interim analysis is one of the reliable and consistent rational approaches to clinical trials that incorporates what is learned during the course of a clinical study and how it is completed without risking the validity or integrity of the study.
This method may include changes in all program-related resources and activities, such as logistical, monitoring, and recruitment procedures.
On a practical level, the study requires not only the ability to continuously measure the outcomes of interest, but also the ability to make data and summarised information about those measurements available in a timely manner to different audiences based on the study role.
In a clinical setting, this entails not only continuously tracking trial data collected on case report forms, but also generating performance metrics that allow for operational refinement.
Interest in this approach has grown as a result of the rising cost of clinical research and numerous trial failures, particularly costly and well-publicized failures of major late-stage trials.
The simplest outcome of such an interim analysis is either an early stop for futility or the continuation of the study.
This logical approach also enables clinical researchers to use the same basic management principles as typical modern businesses, such as using real-time data and analysis to inform decisions that continuously optimise operations.
INTERIM ANALYSIS AND STOPPING RULE
There are several practical and theoretical justifications for using this approach in clinical trials through a variety of group sequential designs that allow a limited number of planned analyses while maintaining a prespecified overall type I error rate and the study’s blind.
The interim analyses should be carried out by a body separate from the one in charge of the clinical trial’s day-to-day operations.
There are several prospective statistical strategies for early termination of a clinical trial.
Negative stopping is considered in flexible strategy and other statistical procedures such as stochastic limitation or conditional power approaches.
Actually, Stopping rules for interim analyses based on limited data require more stringent P values for stopping than stopping rules for later analyses, which can have stopping P values that are close to nominal levels of significance.
So, the key point of Interim Analysis can be:
The decision to conduct an interim analysis should be guided by clinical and statistical integrity, standard operating procedures for interim analyses, and regulatory concerns.
Such a decision should not be based on natural inclinations toward operational or academic curiosity.
As a result, unplanned interim analyses should be avoided because they have the potential to affect the data of a well-planned clinical trial.
A good set of performance metrics allows for a better understanding of the study’s progress, much tighter control, more effective resource allocation (such as monitoring time), faster enrollment, and, in the larger scheme of things, shorter timelines and lower costs in operations and decision-making.”