FL3X Study: An Adaptive Intervention to Improve Outcomes for Youth With Type 1 Diabetes (FL3X)

The FL3X Adaptive Intervention is designed to increase adherence to T1D self-management
including medical management (blood sugar testing and insulin dosing), diet, and physical
activity. FL3X relies on MI, and problem-solving skills training (PSST) as the basis for the
counseling strategy, and creates a coherent integration across three key components of 1)
behavior family systems therapy focused on family communications and teamwork; 2)
individualized diabetes education in response to knowledge gaps relevant to behavioral goal
attainment; and 3) use of currently available communications technology to support behavioral
goal attainment through participant-defined reminders and motivational boosters, and/or peer
support.

All FL3X intervention participants will receive "FL3X-Basic", which is the initial 3-month
intervention that includes 4 sessions (40-60 min), supplemented with short additional
contacts (via text, email, or web-based communication) as needed. Thereafter, applying
principles of adaptive interventions, based on a decision rule using A1c values measured at
defined intervals, participants are iteratively assigned to "FL3X-Check-in" or
"FL3X-Regular", both of which continue with MI and PSST for the underlying counseling
strategy. In FL3X-Check-in, participants who are doing well ("responders") will receive
minimal ongoing support to reinforce successful strategies through brief monthly "touch-base"
contacts. In FL3X-Regular, those who are "Regular-responders" will have a minimum of 3-4
in-person full-length sessions (40-60 min) over each 6-month interval, with additional brief
contacts as needed (e.g., text, voice, or internet). FL3X participants randomized to the
control group will receive usual care.

Inclusion Criteria:

- type 1 diabetes with duration at least 12 months

- between ages 12-16 years at registration

- poor glycemic control (A1c 8.0-13.0%)

- parent/guardian willing to also participate

- not planning on moving in the following 18 months

Exclusion Criteria:

- pregnant (if female)

- diabetes type 2 or gestational

- Pre-existing systemic chronic disease (drug abuse, cancer, certain psychiatric
conditions)