Findings
The goal of sDHT design is to create tools that are functional, intuitive, accessible, and enjoyable to use, moving beyond merely minimizing use-errors. Human-centered design (HCD) is the preferred term over user-centered design, emphasizing the impact on many user groups beyond just the end-users. “Users” encompass end-users (patients/participants), carepartners, clinicians, investigators, and administrators.

Recommendations
Developers of sDHTs should adhere to the following HCD principles:
Empathetic: Take time to deeply understand users’ needs, behaviors, and emotions, capturing this in the use specification.
Holistic: Consider the entire end-to-end user journey, including hardware, software, accessories, packaging, instructions for use, and training.
Iterative: Employ an iterative approach to designing, prototyping, testing, and refining, using formative evaluations to identify use-errors and gather usability data, capturing this in the use-related risk analysis.
User-centric: Improve usability by capturing user feedback in real-world settings, gradually recruiting larger, more diverse samples that represent the intended use population.
Inclusive: Collaborate with individuals representing all user groups by hiring them as consultants or creating user advisory panels to influence design decisions (co-design).
Multidisciplinary: Ensure the development team includes colleagues from various disciplines to bring diverse perspectives and innovative solutions.

Regulatory Considerations
The document ties the HCD process to risk management and eventual validation by recommending that findings from formative evaluations (used to identify use-errors) be captured in a use-related risk analysis. The approach aligns with the principles of the overarching V3+ framework.