4.2 Usability validation
Usability validation is the newest pillar of the V3+ framework, reflecting the realization that even a technically perfect, clinically meaningful sDHT can fail if users cannot easily and correctly use it in the real world.
Usability focuses on the end-user experience: it is defined as the extent to which an sDHT can be used by intended users to achieve specified goals with effectiveness, efficiency, and satisfaction in the intended use environments.
Usability validation asks:
Can intended users use this technology correctly and with ease in its intended use context?”
Usability validation encompasses elements of human factors engineering and user-centered design. Poor usability can lead to user errors, non-adherence, data loss, or even safety issues, undermining the value of the sDHT. Conversely, strong usability means the sDHT and app are intuitive, acceptable, and fit seamlessly into patients’ lives and study workflows, thereby ensuring high-quality data capture and participant adherence.
in practice
Core activities
The usability validation process is often broken into several key activities:
Regulatory and standards alignment
Usability validation in V3+ is aligned with international human factors standards (like ISO 62366 for medical device usability) and FDA guidance on human factors engineering.
Consider context changes
If you are repurposing a marketed sDHT in a new population or setting, do not assume its existing usability data is sufficient. For example, an sDHT cleared for use in adults may need new usability evaluation for use in children, or in cognitively impaired populations (different users = different challenges). The V3+ framework recommends a gap analysis: compare the original intended use vs. your new context to identify any gaps that warrant additional usability testing. Even if an sDHT is already on the market, sponsors should assess whether the trial population can use it as directed, and if not sure, conduct their own usability evaluation.
FDA spotlight
“To demonstrate respect for the patients and/or caregivers who participate and maximize the quality and completeness of information collected in a clinical trial, sponsors should consider ways to minimize the burden of participation and increase the convenience and value of participation to patients and/or caregivers. Early engagement with patient communities (see PFDD Guidance 1) and the involvement of patient representatives in the development of a clinical trial can improve the patient-centeredness of trial procedures and assessments… A failure to evaluate and address potential issues with burden or fatigue can result in a trial with greater missing data, poorer quality data… and/or more dropout.”
– Section IV.A.7 (Minimizing Participant Burden), p. 38
Strategic value
Good usability directly impacts data quality, participant safety, and study efficiency. A highly usable sDHT will yield better adherence (participants are more likely to wear the sDHT correctly and consistently), fewer data gaps, and less need for technical support during a trial. This can significantly lower the burden on study sites and participants.
The impact of usability
Consider a case where poor usability wreaked havoc: in one Parkinson’s disease trial, 50% of participants’ sensor data were missing because of an unintuitive permission setting that many users accidentally turned off. Such an outcome can jeopardize an entire study. Usability validation aims to preempt these issues by ensuring the product is user-centric and failure-resistant.
For participants, a well-designed sDHT improves satisfaction and engagement – they’re more likely to remain in the study or continue using the product in care.
For developers and adopters, it protects the investment: there’s little point validating an endpoint’s clinical relevance if, when deployed, users can’t generate reliable data due to practical difficulties.
Usability validation provides the scalability check – it ensures that your sDHT can move from controlled prototypes to real-world, widespread use without falling apart operationally.
Collaboration & practical tips
Usability is a key area for end-user involvement. Engage patient representatives or target users early in the design and formative testing; their insights are invaluable.
This is also a domain where adopter–developer collaboration shines: developers should drive design and testing of the product itself, but adopters can contribute knowledge of the user population and context.
Jointly, developers and adopters can iterate on solutions (e.g., a developer updates the app; the sponsor adjusts the training materials).
Example
A sponsor might discover through a feasibility study that patients in their trial have trouble with an sDHT’s data upload process due to limited internet access – a usability barrier that can be addressed with an offline data collection mode or phone support.
PRO TIP
Innovative model
Consider establishing a user advisory panel or “living lab” for your sDHT. This panel (including patients, clinicians, study coordinators) can provide continual feedback on usability in real-world use and help co-create fixes. Some organizations have implemented collaborative design programs where end-users and product teams work together to refine a digital health tool before broad deployment – greatly improving uptake and success.
Embracing human-centered design as an ongoing practice, not a one-time checkbox, will pay dividends in smoother adoption. This is a great exercise to design when considering which stakeholders you need input from for successful sDHT adoption (see Section 2.2: Context of use).
When planning a clinical trial with an sDHT, budget and schedule for a pilot run or dry run specifically to test usability. A small rehearsal with a few participants can reveal unanticipated issues (e.g., pairing the tech with a phone takes longer than expected, or instructions are confusing). It’s better to tweak and retrain before the full study launches. Additionally, have a clear support plan (helpdesk, manuals, in-app tips) in place – good usability validation will inform what support users need. Often, something as simple as improving the instructions for use based on usability testing can dramatically reduce error rates.
Finally, document all usability findings and improvements; this evidence may be requested by regulators or ethics committees, and it demonstrates due diligence in protecting participants and data integrity.
4.2 Usability validation
Library resources to guide you
The sDHT roadmap library gathers 200+ external resources to support the adoption of sensor-based digital health technologies. To help you apply the concepts in this section, we’ve curated specific spotlights that provide direct access to critical guidance and real-world examples, helping you move from strategy to implementation.
Features essential guidance, publications, and communications from regulatory bodies relevant to this section. Use these resources to inform your regulatory strategy and ensure compliance.
Gathers real-world examples, case studies, best practices, and lessons learned from peers and leaders in the field relevant to this section. Use these insights to accelerate your work and avoid common pitfalls.