Designing a Pilot Sequential Multiple Assignment Randomized Trial for Developing a Dynamic Treatment Regime

• Activity Number: 469
• Type: Topic Contributed
• Date/Time: Wednesday, August 7, 2013 : 8:30 AM to 10:20 AM
• Sponsor: Mental Health Statistics Section
• Author(s): Daniel Almirall*+ and Scott N. Compton and Meredith Gunlicks-Stoessel and Naihua Duan and Susan Murphy
• Companies: University of Michigan and Duke University and University of Minessota and Departments of Psychiatry and Biostatistics, Columbia University and University of Michigan
• Keywords: dynamic treatment regime ; adaptive treatment strategy ; clinical trial ; pilot study ; sequential randomization ; sample size

Abstract

There is growing interest in how best to adapt and re-adapt treatments to individuals to maximize clinical benefit. In response to this interest, scientists have begun to consider how to develop dynamic treatment regimes (DTR), which provide a guide to the adaptive, sequential clinical decision making that takes place in actual clinical practice. Sequential multiple assignment randomized trials (SMART) have been developed to address the sequencing questions that arise in the development of DTRs, but SMARTs are relatively new in clinical research. This talk introduces DTRs and SMARTs. Specifically, we discuss the design of SMART pilot studies to address feasibility concerns, and to prepare investigators for a full-scale SMART. We consider an example SMART for the development of a DTR in the treatment of pediatric anxiety. We identify and discuss design issues unique to SMARTs that are best addressed in a pilot study prior to the full-scale SMART. We also address the question of how many participants are needed in a SMART pilot study. A properly executed pilot study can be used to effectively address concerns about acceptability and feasibility prior to conducting a full-scale SMART.