Integration of a Digital Health Intervention Into Immunization Clinic Workflows in Kenya: Qualitative, Realist Evaluation of Technology Usability.

We created a deeper understanding of the underlying mechanisms for usability of the registry. We found that the electronic immunization registry had high acceptability among users; however, there were numerous barriers to using the system, even under ideal conditions, causing a misalignment between the system and the reality of the users' workflows and their environment. Human-centered design and human-factors methods can assist during pilot stages to better align systems with users' needs and again after scale-up to ensure that interventions are suitable for all user settings.