Objective: To understand and explore data sharing practices among adolescents and their parents using a closed-loop system. Methods: Eighteen adolescents (aged 11-18 years) and 19 parents were interviewed after adolescents had ∼6 months experience of using a closed-loop system, which permitted them to share glucose and insulin data with parents/caregivers. Data were analyzed thematically. Results: There was considerable variability in how parent-child dyads perceived, valued, and undertook data sharing. Parents of early adolescents (11-13 years) reported making extensive use of "real time" data to remotely manage their child's diabetes and early adolescents described needing and wanting this input. Parents of middle adolescents (14-16 years) described making greater use of retrospective data. To avoid conflict and encourage and support their son/daughter's autonomy, these individuals reported practicing watchful waiting and only intervening after concerns about a pattern of problematic behavior or their child's safety arose. Middle adolescents indicated that data sharing had been done primarily for the benefit of their parents, although they also noted quality of life benefits for themselves. Among late adolescents (17+ years), parents were simply remote because their son/daughter had not permitted access to their data. Participants recommended clear ground rules be put in place about when, and how, data sharing should be used. Conclusions: To help parent-child dyads use data sharing in ways which minimize conflict and optimize constructive parental support, we recommend tailored input and support, which takes account of family dynamics, the young person's developmental maturity, and the different ways in which data are used across the adolescent age range
