On February 27, 2020 we released our eighth short video, Methods for Using Multiple Treatments Within the Same Subject. This topic is presented by Dr. Melanie Quintana of Berry Consultants, LLC. 


 A standard two group trial (often called a parallel design) investigates two therapies in different sets of people. In parallel designs observed differences in treatment may be partially due to differences in the people within each group. To alleviate this concern we employ designs which test each therapy within each patient, often called crossover designs, removing patient differences from the comparison. Where this is feasible, often in chronic as opposed to acute conditions, eliminating the across patient noise can significantly increase the power of our trials and/or decrease the required sample size. In this talk Dr. Melanie Quintana will demonstrate the differences between parallel and crossover designs, the statistical advantages, implementation issues such as carryover effects and the need for shorter term endpoints, and advanced topics such as rerandomization.