The purpose of this study is to conduct a multicenter, randomized effectiveness trial of The 3Ms 2.0 compared to an educational control condition for improving adolescent glycemic control and diabetes-related family relationships and reducing primary caregiver diabetes-related distress among Black adolescents with type 1 diabetes (T1D) and their primary caregivers. The proposed study would develop and test The 3Ms 2.0 adapted intervention when delivered using a mobile health approach (accessed via parents' cell phone). The intervention will also include new family intervention content (videoclips and text messages).

The proposed study is a multi-center randomized controlled trial (RCT) examining the efficacy of The 3Ms 2.0 compared to an educational attention control condition (EAC) for improving adolescent glycemic control and diabetes-related family relationships and reducing primary caregiver diabetes-related distress among Black adolescents with type 1 diabetes (T1D) and their primary caregivers. A randomized, controlled, repeated measures design will be used. The study will use a sample of 216 Black adolescent-caregiver dyads. Participants will be recruited at two sites (University of Tennessee Health Sciences Center/ LeBonheur Children's Hospital and Children's National Hospital in Washington, DC). 108 families will be recruited at each of the two sites. Wayne State University (WSU) will function as the coordinating center for the trial and will be responsible for overseeing the adequacy of all aspects of trial management.

Participants will be randomly assigned in a 1:1 ratio to receive The 3Ms 2.0 plus standard medical care or EAC plus standard medical care. In the 3Ms 2.0 condition, primary caregivers will receive a brief (10-20 minute) 3 session computer-delivered intervention via their mobile device. The intervention is designed to increase parental daily supervision of adolescent diabetes management. In the control condition, primary caregivers will also receive 3 brief computer-delivered sessions where the content is information and facts about type 1 diabetes. The intervention content will be available to the primary caregiver during a six month window and can be completed at their convenience.

Data collection occurs in the families' home at baseline (T1), three months post-baseline (corresponding with the midpoint of the intervention window) (T2), six months post- baseline (corresponding with the end of the intervention window) (T3) and 12 months post-baseline (T4). Data completion can be completed via the Internet should families live outside a reasonable driving distance from the recruitment site. Data collection is completed by the adolescent and caregiver on a tablet computer and includes questionnaires to assess adolescent diabetes management, parental supervision of diabetes management, family relationships and youth quality of life. Blood will also be collected to measure HbA1c (mean blood glucose level). Medical record data will also be collected.

The data analyses will be intent-to-treat, meaning that all randomized participants are included regardless of the intervention dose received. Trial data will analyzed using the linear mixed effect model (LME) for repeated measures.

Inclusion Criteria:

• Age: 10 years, 0 months - 14 years, 11 months
• Diagnosed with Type 1 diabetes
• Diagnosed for at least 6 months
• Black
• Primary caregiver willing to participate
• Residence within 30 miles of a recruitment site
• Caregiver ownership of an Internet-enabled device (cell phone, laptop or desktop computer, tablet, etc)

Exclusion Criteria:

• Mental health conditions that might compromise data integrity (e.g., developmental delay, schizophrenia, psychosis, current suicidality, homicidality)
• Co-morbid medical condition resulting in atypical diabetes management (e.g., cystic fibrosis)
• Inability to speak or read English
• Child is in out-of-home placement

Identifiers will be removed from the data prior to any release of the dataset. The final data set will include data obtained from medical records, data obtained directly from participants on diabetes health status, behavioral data, and intervention data. Participants in the trial will be recruited through two children's hospitals. Even though the final dataset will not contain identifiers, given the relatively small sample size and focus on Black youth, there remains the possibility of deductive identification of subjects with unusual characteristics (i.e. high number hospital admissions).

June 2029

Given the sensitive nature of the health data contained in the data set, as well as the participation of children, the data and associated documentation will be available to users under a specific data-sharing agreement that provides for: (1) a commitment to using the data only for research purposes and not to identify any individual participant; (2) a commitment to securing the data using appropriate technology; and (3) a commitment to destroying the data after analyses are completed.