A1C at baseline, 16 weeks, and 32 weeks according to study group in all participants (A), adult participants (B), and adolescent participants (C) who returned for the 32-week visit. A1C at baseline, 16 weeks, and 32 weeks according to study group in all participants (A), adult participants (B), and adolescent participants (C) who returned for the 32-week visit. D: Number of interactions with handsets providing “reactive” guidelines on how to respond to real-time glucose levels. *P < 0.05, compared with baseline for the 16-week data and compared with 16 weeks for the 32-week data. **P < 0.0001, 16 weeks compared with baseline. Alicia J. Jenkins et al. Dia Care 2010;33:1242-1248 ©2010 by American Diabetes Association