Discussion
The current paper used a case study to demonstrate how SMART design researchers can conduct multiple randomizations despite the lack of accessible software capable of conducting automated multiple randomizations. Namely, we illustrated a strategy that our research team successfully used to automatically randomize participants multiple times to different interventions using REDCap.As adaptive interventions have emerged as a new approach to research-based prevention and treatment, SMART designs have been gaining popularity. According to the NIH’s Research Portfolio Online Reporting Tools (RePORT) website, which allows users to search a repository of both intramural and extramural NIH-funded research projects and access publications and patents resulting from NIH funding, 109 NIH-funded projects used SMART design during the 2022 calendar year. The Fig. 
NIH-funded SMART design projects by yearAs SMART design gains increasing recognition and is increasingly implemented in practice, demand for software capable of performing the unique multiple randomization assignments required for SMARTs will also increase. Encouragingly, our strategy of utilizing API for the double randomization procedure was seamlessly implemented in conjunction with the REDCap platform. This strategy eliminated technological and logistical challenges by effectively concealing and masking intervention allocation sequences to investigators, involved health care providers, and subjects as they progressed through the complex SMART study procedures. At the same time, challenges common to all rigorous clinical trials (e.g., study invitations, eligibility screening, consenting procedure, data collection, and data confidentiality protocols) were addressed adequately through unique features of the REDCap platform. Additional benefits of using API in conjunction with REDCap for our SMART design project included: timely completion of complex intervention assignments, accurate assignments for participants at multiple time points, and the ability to reduce both the human resources required to implement the study and the likelihood of human error by automating most of the study procedures.Although this strategy worked very well for our research team, some contextual factors might influence how other researchers adapt the strategy to their projects in different organizations. The global REDCap community may develop an add-on that accomplishes multiple randomizations within a single project. However, there may be a lag between its release and the ability of organizations to deploy it on different REDCap instances. For example, the University of Illinois at Urbana-Champaign’s REDCap instance, which housed our project, had a built-in Health Insurance Portability and Accountability Act (HIPAA)-compliant AWS account. The University also took steps to guarantee the security of the software. Most importantly, the Illinois REDCap instance undergoes an annual security review with the university’s Cybersecurity Governance, Risk, and Compliance (GRC) team. The review evaluates Illinois REDCap’s ability to meet a variety of security controls and measures in accordance with HIPAA and the University’s cybersecurity standards. In addition to the annual review, REDCap users are required to complete HIPAA training before accessing the system, system sign-on utilizes Shibboleth two-factor authentication, and projects are vetted by REDCap administration team for required protections before a project is moved to production to ensure security. Thus, due to the secure nature of Illinois REDCap, our process of integrating third-party solutions within REDCap was rigorous. The add-on was inspected for compliancy and potential vulnerabilities, then tested on a TEST server. Additionally, documentation and standard operating procedures for how the add-on will be upgraded and accessed by users were developed by the University.The unique context of each organization must be taken in consideration before implementing this multiple randomization solution. Whereas our research team was able to successfully utilize the built-in HIPAA-compliant AWS account to implement our strategy in conjunction with rigorous REDCap team administration support for data security and protection, other research teams may not have the same resources and administrative support. Some of the ways in which research teams with limited resources to readily implement this strategy may consider consulting REDCap community that is very active in providing recommendations and support.