Members of the NIH Collaboratory’s Biostatistics and Study Design Core contributed 3 new sections to the Living Textbook exploring issues in the design and analysis of pragmatic clinical trials. The new sections offer insights into emerging issues in embedded pragmatic clinical trials and lessons learned from the NIH Collaboratory’s first round of Demonstration Projects.
- The Designing to Avoid Identification Bias section addresses a type of selection bias that can occur in pragmatic clinical trials that use information from electronic health records to determine study population eligibility and in which the study intervention influences who undergoes screening or receives a diagnosis in clinical care.
- The Alternative Cluster Randomized Designs section describes alternative design choices for cluster randomized trials and their implications for statistical power and sample size calculations. Modified cluster randomized designs, such as cluster randomization with crossover, may reduce the sample size required for a pragmatic clinical trial and may be particularly feasible in trials embedded in healthcare systems with electronic health records.
- Case Study: STOP CRC Trial explores challenges in design and analysis that were faced in the Strategies and Opportunities to Stop Colorectal Cancer in Priority Populations (STOP CRC) trial, one of the NIH Collaboratory Demonstration Projects. The case study illustrates how the study team dealt with pragmatic issues during the planning and conduct of the trial.
In addition to contributing content to the Living Textbook, the Biostatistics and Study Design Core works with the NIH Collaboratory Demonstration Projects to address challenges in their statistical plans and study designs during the planning phase and to develop guidance and technical documents related to study design and biostatistical issues relevant to pragmatic clinical trials.