The Goldilocks Dilemma on Balancing User Response and Reflection in mHealth Interventions: Observational Study.

Background: Mobile health (mHealth) has the potential to radically improve health behaviors and quality of life; however, there are still key gaps in understanding how to optimize mHealth engagement. Most engagement research reports only on system use without consideration of whether the user is reflecting on the content cognitively. Although interactions with mHealth are critical, cognitive investment may also be important for meaningful behavior change. Notably, content that is designed to request too much reflection could result in users' disengagement. Understanding how to strike the balance between response burden and reflection burden has critical implications for achieving effective engagement to impact intended outcomes. Objective: In this observational study, we sought to understand the interplay between response burden and reflection burden and how they impact mHealth engagement. Specifically, we explored how varying the response and reflection burdens of mHealth content would impact users' text message response rates in an mHealth intervention. Methods: We recruited support persons of people with diabetes for a randomized controlled trial that evaluated an mHealth intervention for diabetes management. Support person participants assigned to the intervention (n=148) completed a survey and received text messages for 9 months. During the 2-year randomized controlled trial, we sent 4 versions of a weekly, two-way text message that varied in both reflection burden (level of cognitive reflection requested relative to that of other messages) and response burden (level of information requested for the response relative to that of other messages). We quantified engagement by using participant-level response rates. We compared the odds of responding to each text and used Poisson regression to estimate associations between participant characteristics and response rates. Results: The texts requesting the most reflection had the lowest response rates regardless of response burden (high reflection and low response burdens: median 10%, IQR 0%-40%; high reflection and high response burdens: median 23%, IQR 0%-51%). The response rate was highest for the text requesting the least reflection (low reflection and low response burdens: median 90%, IQR 61%-100%) yet still relatively high for the text requesting medium reflection (medium reflection and low response burdens: median 75%, IQR 38%-96%). Lower odds of responding were associated with higher reflection burden (P<.001). Younger participants and participants who had a lower socioeconomic status had lower response rates to texts with more reflection burden, relative to those of their counterparts (all P values were <.05). Conclusions: As reflection burden increased, engagement decreased, and we found more disparities in engagement across participants' characteristics. Content encouraging moderate levels of reflection may be ideal for achieving both cognitive investment and system use. Our findings provide insights into mHealth design and the optimization of both engagement and effectiveness.

Using Community Engagement Methods to Guide Study Protocol Decisions for School-Aged Children With Type 1 Diabetes.

Introduction: Many challenges exist in developing multisite protocols for newly diagnosed children with type 1 diabetes. Our research team engaged community members to increase the likelihood of study success during a planning grant for a longitudinal study aimed at understanding risk and protective factors for neurocognitive function in school-aged children newly diagnosed with type 1 diabetes. Methods: Two methods were used to obtain caregiver input into study protocol decisions. The first was a survey given to caregivers of children with diabetes (n = 21) about which aspects of the study protocol would make families more or less likely to participate. The second was a Community Engagement (CE) Studio to obtain recommendations from a diverse group of caregivers of children with diabetes (n = 7) on key aspects of recruitment and enrollment. Results: Results from both the survey and the CE Studio indicated that caregivers were interested and willing to participate in a longitudinal study of this nature. Both methods resulted in similar preferences for the type and amount of compensation, convenient study visits, flexible scheduling options, and receipt of neurocognitive test results. Recommendations from the CE Studio included additional strategies to minimize participant burden and enhance communication around study participation. Conclusion: Both the feasibility survey and the CE Studio were useful mechanisms to obtain caregiver input during the study's planning and design phase. Uniquely, the CE Studio approach offers researchers the ability to gain valuable community member input with minimal staff effort.

Detangling Associations Between Maternal Depressive Symptoms and Diabetes Relationship Distress With Adolescents' HbA1c.

OBJECTIVE : Previous research in families of children with type 1 diabetes demonstrates that maternal depressive symptoms are a known risk factor for poor diabetes outcomes. We sought to examine whether maternal diabetes relationship distress or maternal depressive symptoms were more strongly associated with adolescent glycemic outcomes. METHODS : Analyses were conducted using data from mothers who consented to screen for a behavioral intervention. The screener included the Patient Health Questionnaire and the Parent Diabetes Distress Scale, Parent/Teen Relationship Distress subscale. Hemoglobin A1c (HbA1c) was extracted from adolescents' medical records. RESULTS : Our sample consisted of 390 maternal caregivers of adolescents with type 1 diabetes aged 11-17. Screening data revealed that 35% of mothers reported clinically significant diabetes distress related to their relationship with their adolescents, and 14% of mothers reported clinically significant depressive symptoms. The adolescents of mothers who reported diabetes relationship distress had significantly higher mean HbA1c levels (9.7 ± 2.2%) compared to those whose mothers were not distressed (8.2 ± 1.8%, d = .72). Similarly, adolescents whose mothers reported clinically significant depressive symptoms had higher mean HbA1c levels (9.6 ± 2.4%) than those whose mothers were not depressed (8.6 ± 2.0%, d = .48). After adjusting for clinical and demographic factors, mothers' reports of diabetes relationship distress were more strongly associated with adolescents' HbA1c than maternal depressive symptoms. CONCLUSIONS : Our findings suggest that screening for maternal distress-particularly distress related to the caregiver-adolescent relationship-could match families with psychosocial support or other resources to improve both psychosocial and glycemic outcomes.

Glycemic outcomes of a family-focused intervention for adults with type 2 diabetes: Main, mediated, and subgroup effects from the FAMS 2.0 RCT.

AIMS: Family/friend Activation to Motivate Self-care (FAMS) is a self-care support intervention delivered via mobile phones. We evaluated FAMS' effects on hemoglobin A1c (HbA1c) and intervention targets among adults with type 2 diabetes in a 15-month RCT. METHODS: Persons with diabetes (PWDs) were randomized to FAMS or control with their support person (family/friend, optional). FAMS included monthly phone coaching and text messages for PWDs, and text messages for support persons over a 9-month intervention period. RESULTS: PWDs (N = 329) were 52 % male, 39 % reported minoritized race or ethnicity, with mean HbA1c 8.6 ± 1.7 %. FAMS improved HbA1c among PWDs with a non-cohabitating support person (-0.64 %; 95 % CI [-1.22 %, -0.05 %]), but overall mean effects were not significant. FAMS improved intervention targets including self-efficacy, dietary behavior, and family/friend involvement during the intervention period; these improvements mediated post-intervention HbA1c improvements (total indirect effect -0.27 %; 95 % CI [-0.49 %, -0.09 %]) and sustained HbA1c improvements at 12 months (total indirect effect -0.19 %; 95 % CI [-0.40 %, -0.01 %]). CONCLUSIONS: Despite improvements in most intervention targets, HbA1c improved only among PWDs engaging non-cohabitating support persons suggesting future family interventions should emphasize inclusion of these relationships. Future work should also seek to identify intervention targets that mediate improvements in HbA1c.

Evaluation of Study Engagement With an mHealth Intervention (THR1VE) to Treat Diabetes Distress in Teens With Type 1 Diabetes: Randomized Clinical Trial.

Background: Positive psychology interventions demonstrate improvements in diabetes self-management and quality of life among adults with chronic health conditions, but few interventions for adolescents use this approach. Objective: This study describes engagement with a positive psychology intervention delivered via automated SMS text messages aimed at treating diabetes distress and improving diabetes outcomes. In addition, demographic and clinical predictors of intervention engagement were examined. Methods: Adolescents with type 1 diabetes (ages 13-17 years) who reported at least moderate diabetes distress were randomized to receive either the education or positive affect + education intervention, comprising 8 weeks of automated SMS text messages. Engagement was assessed as the response to the SMS text messages. Adolescents completed satisfaction surveys 3 months post intervention, and a subset of participants from both intervention groups completed exit interviews. Results: Adolescents in both groups reported high levels of satisfaction with the study, with 95% (163/172) reporting that they would participate again. Engagement with the SMS text messages was high; on average, adolescents in the positive affect + education group responded to 92.5% of intervention messages, and their caregivers responded to 88.5% of messages. There were no significant differences in rates of engagement related to adolescents' sex, age, device use, or race/ethnicity. Conclusions: A positive psychology intervention for adolescents delivered via automated SMS text messages was feasible and acceptable across genders, ages, and racial/ethnic groups, suggesting potential for wider dissemination.

Well-being outcomes of a family-focused intervention for persons with type 2 diabetes and support persons: Main, mediated, and subgroup effects from the FAMS 2.0 RCT.

AIMS: Type 2 diabetes self-management occurs within social contexts. We sought to test the effects of Family/friend Activation to Motivate Self-care (FAMS), a self-care support intervention delivered via mobile phones, on psychosocial outcomes for persons with diabetes (PWDs) and their support persons. METHODS: PWDs had the option to enroll with a friend/family member as a support person in a 15-month RCT to evaluate FAMS versus enhanced usual care. FAMS included 9 months of monthly phone coaching and text message support for PWDs, and text message support for enrolled support persons. RESULTS: PWDs (N = 329) were 52% male and 39% reported minoritized race or ethnicity ; 50% enrolled with elevated diabetes distress. Support persons (N = 294) were 26% male and 33% reported minoritized race or ethnicity. FAMS improved PWDs' diabetes distress (d = -0.19) and global well-being (d = 0.21) during the intervention, with patterns of larger effects among minoritized groups. Post-intervention (9-month) and sustained (15-month) improvements were driven by changes in PWDs' self-efficacy, self-care behaviors, and autonomy support. Among support persons, FAMS improved helpful involvement without increasing burden or harmful involvement. CONCLUSIONS: FAMS improved PWDs' psychosocial well-being, with post-intervention and sustained improvements driven by improved self-efficacy, self-care, and autonomy support. Support persons increased helpful involvement without adverse effects.

Well-being outcomes of a family-focused intervention for persons with type 2 diabetes and support persons: Main, mediated, and subgroup effects from the FAMS 2.0 RCT.

Aims: Type 2 diabetes self-management occurs within social contexts. We sought to test the effects of Family/friends Activation to Motivate Self-care (FAMS), a self-care support intervention delivered via mobile phones, on psychosocial outcomes for persons with diabetes (PWDs) and their support persons. Methods: PWDs had the option to enroll with a friend/family member as a support person in a 15-month RCT to evaluate FAMS versus enhanced usual care. FAMS included 9-months of monthly phone coaching and text message support for PWDs, and text message support for enrolled support persons. Results: PWDs (N=329) were 52% male and 39% from minoritized racial or ethnic groups; 50% enrolled with elevated diabetes distress. Support persons (N=294) were 26% male and 33% minoritized racial or ethnic groups. FAMS improved PWDs' diabetes distress ( d =-0.19) and global well-being ( d =0.21) during the intervention, with patterns of larger effects among minoritized groups. Post-intervention and sustained (15-month) improvements were driven by changes in PWDs' self-efficacy, self-care behaviors, and autonomy support. Among support persons, FAMS improved helpful involvement without increasing burden or harmful involvement. Conclusions: FAMS improved PWDs' psychosocial well-being, with post-intervention and sustained improvements driven by improved self-efficacy, self-care, and autonomy support. Support persons increased helpful involvement without adverse effects.

Glycemic outcomes of a family-focused intervention for adults with type 2 diabetes: Main, mediated, and subgroup effects from the FAMS 2.0 RCT.

Aims: Family/friends Activation to Motivate Self-care (FAMS) is a self-care support intervention delivered via mobile phones. We evaluated FAMS effects on hemoglobin A1c (HbA1c) and intervention targets among adults with type 2 diabetes in a 15-month RCT. Methods: Persons with diabetes (PWDs) and their support persons (family/friend, optional) were randomized to FAMS or control. FAMS included monthly phone coaching and text messages for PWDs, and text messages for support persons over a 9-month intervention period. Results: PWDs (N=329) were 52% male, 39% from minoritized racial or ethnic groups, with mean HbA1c 8.6±1.7%. FAMS improved HbA1c among PWDs with a non-cohabitating support person (-0.64%; 95% CI [-1.22%, -0.05%]), but overall effects were not significant. FAMS improved intervention targets including self-efficacy, dietary behavior, and family/friend involvement during the intervention period; these improvements mediated post-intervention HbA1c improvements (total indirect effect -0.27%; 95% CI [-0.49%, -0.09%]) and sustained HbA1c improvements at 12 months (total indirect effect -0.19%; 95% CI [-0.40%, -0.01%]). Conclusions: Despite improvements in most intervention targets, HbA1c improved only among PWDs engaging non-cohabitating support persons suggesting future family interventions should emphasize inclusion of these relationships. Future work should also seek to identify intervention targets that mediate improvements in HbA1c.

Prerandomization withdrawals from a Type 2 diabetes self-care support intervention trial are associated with lack of available support person coparticipant.

OBJECTIVES: Dyadic interventions, involving two persons with a preexisting close relationship, offer the opportunity to activate support persons (SPs) to improve health for adults with chronic conditions. Requiring SP coparticipation can challenge recruitment and bias samples; however, the associations between voluntary SP coparticipation and recruitment outcomes across patient characteristics are unknown. METHODS: The Family/Friend Activation to Motivate Self-care 2.0 randomized controlled trial (RCT) enrolled adults with Type 2 diabetes (T2D) from an academic health system. Participants were asked-but not required-to invite an SP to coenroll. Using data from the electronic health record we sought to describe RCT enrollment in the setting of voluntary SP coparticipation. RESULTS: In a diverse sample of adults with (T2D) (48% female, 44% minoritized race/ethnicity), most participants (91%) invited SPs and (89%) enrolled with SPs. However, prerandomization withdrawal was significantly higher among participants who did not have consenting SPs than those who did. Females were less likely to invite SPs than males and more Black PWD were prerandomization withdrawals than randomized. DISCUSSION: Voluntary SP coenrollment may benefit recruitment for dyadic sampling; however, more research is needed to understand if these methods systematically bias sampling and to prevent these unintended biases.

Disparities in mobile phone use among adults with type 2 diabetes participating in clinical trials 2017-2021.

Despite smartphone ownership becoming ubiquitous, it is unclear whether and where disparities persist in experience using health apps. In 2 diverse samples of adults with type 2 diabetes collected 2017-2018 and 2020-2021, we examined adjusted disparities in smartphone ownership and health app use by age, gender, race, education, annual household income, health insurance status, health literacy, and hemoglobin A1c. In the earlier sample (N = 422), 87% owned a smartphone and 49% of those had ever used a health app. Participants with lower income or limited health literacy had ≥50% lower odds of owning a smartphone. Comparatively, in the later sample (N = 330), almost all participants (98%) owned a smartphone and 70% of those had ever used a health app; however, disparities in health app use closely mirrored disparities in smartphone ownership from 2017 to 2018. Our findings suggest device ownership is necessary but insufficient for assuming people will use apps to support their health.

Multimodal neuroimaging in pediatric type 1 diabetes: a pilot multisite feasibility study of acquisition quality, motion, and variability.

Type 1 diabetes (T1D) affects over 200,000 children and is associated with an increased risk of cognitive dysfunction. Prior imaging studies suggest the neurological changes underlying this risk are multifactorial, including macrostructural, microstructural, and inflammatory changes. However, these studies have yet to be integrated, limiting investigation into how these phenomena interact. To better understand these complex mechanisms of brain injury, a well-powered, prospective, multisite, and multimodal neuroimaging study is needed. We take the first step in accomplishing this with a preliminary characterization of multisite, multimodal MRI quality, motion, and variability in pediatric T1D. We acquire structural T1 weighted (T1w) MRI, diffusion tensor MRI (DTI), functional MRI (fMRI), and magnetic resonance spectroscopy (MRS) of 5-7 participants from each of two sites. First, we assess the contrast-to-noise ratio of the T1w MRI and find no differences between sites. Second, we characterize intervolume motion in DTI and fMRI and find it to be on the subvoxel level. Third, we investigate variability in regional gray matter volumes and local gyrification indices, bundle-wise DTI microstructural measures, and N-acetylaspartate to creatine ratios. We find the T1-based measures to be comparable between sites before harmonization and the DTI and MRS-based measures to be comparable after. We find a 5-15% coefficient of variation for most measures, suggesting ~150-200 participants per group on average are needed to detect a 5% difference across these modalities at 0.9 power. We conclude that multisite, multimodal neuroimaging of pediatric T1D is feasible with low motion artifact after harmonization of DTI and MRS.

Rationale, design, and recruitment outcomes for the Family/Friend Activation to Motivate Self-care (FAMS) 2.0 randomized controlled trial among adults with type 2 diabetes and their support persons.

BACKGROUND: Self-care behaviors help reduce hemoglobin A1c (HbA1c) and prevent or delay type 2 diabetes (T2D) complications. Individualized interventions that support goal setting and self-monitoring improve self-care and HbA1c in the short-term; engaging family and friends may enhance and/or sustain effects. Family/Friend Activation to Motivate Self-care (FAMS) is a mobile phone-delivered intervention (i.e., phone coaching and text message support) based on Family Systems Theory which was successfully piloted among diverse adults with T2D. METHODS: We made improvements to FAMS and conducted iterative usability testing to finalize FAMS 2.0 before evaluation in a randomized controlled trial (RCT). Adult persons with diabetes (PWDs) who enrolled were asked to invite a support person (friend or family member) to participate alongside them. For the RCT, dyads were randomly assigned to FAMS 2.0 or enhanced treatment as usual (control) for the first 9 months of the 15-month trial. Outcomes include PWDs' HbA1c and psychosocial well-being (including diabetes distress) and support persons' own diabetes distress and support burden. RESULTS: We recruited RCT participants from April 2020 through October 2021 (N = 338 PWDs with T2D; 89% [n = 300] with a support person). PWDs were 52% male, 62% non-Hispanic White, aged 56.9 ± 11.0 years with HbA1c 8.7% ± 1.7% at enrollment; 73% cohabitated with their enrolled support person. Data collection is ongoing through January 2023. CONCLUSION: Findings will inform the utility of engaging family/friends in self-care behaviors for both PWD and support person outcomes. Using widely available mobile phone technology, FAMS 2.0, if successful, has potential for scalability. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04347291 posted April 15, 2020.

Demographic and Glycemic Factors Linked With Diabetes Distress in Teens With Type 1 Diabetes.

OBJECTIVE: Diabetes distress (DD) is a negative emotional response related to the burdens of living with type 1 diabetes (T1D) and is linked with diabetes outcomes, such as hemoglobin A1c (A1c). Yet, less is known about how other glycemic indicators, average blood glucose and time in range, relate to DD, and which demographic characteristics are associated with higher DD. METHODS: In total, 369 teens (Mage 15.6 ± 1.4, 51% female, MT1D duration 6.7 ± 3.8 years) screened for DD using The Problem Areas in Diabetes-Teen Version to determine eligibility for an ongoing multi-site behavioral trial. The associations of DD, demographic factors, and glycemic indicators (A1c, average blood glucose, and time in range) were analyzed. RESULTS: Twenty-nine percent of teens (n = 95) scored above the clinical cutoff (≥44) for DD. Females scored significantly higher on average than males. Black/African American, non-Hispanic youth screened significantly higher compared to youth from other racial/ethnic groups. Higher DD scores were related to higher A1c and average blood glucose, and lower time in range. Logistic regression models revealed that females were significantly more likely to report clinically elevated DD than males, and teens with higher A1c were 1.3 times more likely to report DD. Age and diabetes duration were not significantly associated with clinically elevated DD scores. CONCLUSIONS: Results demonstrated that DD is most prevalent in Black, non-Hispanic and female teens, and DD is associated with higher average blood glucose and lower time in range. Further investigation into these disparities is warranted to promote optimal health outcomes for teens with T1D.

Exploring determinants and strategies for implementing self-management support text messaging interventions in safety net clinics.

Background: Text message-delivered interventions for chronic disease self-management have potential to reduce health disparities, yet limited research has explored implementing these interventions into clinical care. We partnered with safety net clinics to evaluate a texting intervention for type 2 diabetes called REACH (Rapid Encouragement/Education And Communications for Health) in a randomized controlled trial. Following evaluation, we explored potential implementation determinants and recommended implementation strategies. Methods: We interviewed clinic staff (n = 14) and a subset of intervention participants (n = 36) to ask about REACH's implementation potential. Using the Consolidated Framework for Implementation Research (CFIR) as an organizing framework, we coded transcripts and used thematic analysis to derive implementation barriers and facilitators. We integrated the CFIR-ERIC (Expert Recommendations for Implementing Change) Matching Tool, interview feedback, and the literature to recommend implementation strategies. Results: Implementation facilitators included low complexity, strong evidence and quality, available clinic resources, the need for a program to support diabetes self-management, and strong fit between REACH and both the clinics' existing workflows and patients' needs and resources. The barriers included REACH only being available in English, a lack of interoperability with electronic health record systems, patients' concerns about diabetes stigma, limited funding, and high staff turnover. Categories of recommended implementation strategies included training and education, offering flexibility and adaptation, evaluating key processes, and securing funding. Conclusion: Text message-delivered interventions have strong potential for integration in low-resource settings as a supplement to care. Pursuing implementation can ensure patients benefit from these innovations and help close the research to practice gap.

Pivoting during a pandemic: lessons learned from transitioning a multisite randomized controlled trial to a remote protocol in response to COVID-19.

THR1VE! is an ongoing multisite randomized clinical trial of a positive psychology intervention designed to treat diabetes distress and improve glycemic outcomes in teens with type 1 diabetes. Due to the COVID-19 pandemic restrictions on clinical research and changes in diabetes clinical care, THR1VE! was adapted from an in-person enrollment protocol to a remote protocol through a series of development and testing strategies. We discuss the process of transitioning the protocol and the demonstrated feasibility of ongoing recruitment, enrollment, and retention outcomes. These findings offer support for a remotely transitioned protocol that has larger applications for ongoing and future clinical research.

Retaining diverse adults with diabetes in a long-term trial: Strategies, successes, and lessons learned.

Background Retention can be difficult in longitudinal trials, especially among minoritized groups and individuals with low socioeconomic status (SES) who may experience more barriers to research participation. Organized retention strategies may help; however, limited research has reported on this in detail. Methods We employed several strategies throughout a 15-month randomized controlled trial to encourage retention among a diverse sample of adults with type 2 diabetes. Participants were randomized to receive mobile health support for diabetes self-care for 12 months or an attention control. Participants completed assessments at 3, 6, 12, and 15 months post-baseline. We used three main categories of retention strategies: flexibility in participation (e.g., multiple methods for data collection), communication (e.g., tracking contacts), and community building (e.g., study branding, newsletters). We monitored participants' use of strategies and examined associations between participant characteristics and retention. Results Retention remained high (≥90%) at each follow-up assessment. Participants used various methods for survey completion: online (34%), in-person (31%), and mail (30%). Most (73%) used a mail-in A1c kit at least once. Multiple completion methods were important for retaining minoritized and lower SES participants who completed assessments in-person more frequently. Communication also facilitated retention; 39% of participants used a study Helpline and tracking systems helped maintain contact. Conclusions Retaining disadvantaged patients in clinical trials is necessary so findings generalize to and can benefit these populations. Retention strategies that reduce barriers to participation and engage participants and community partners can be successful. Future studies should assess the impact of retention strategies.

COVID-19 Severity Is Tripled in the Diabetes Community: A Prospective Analysis of the Pandemic's Impact in Type 1 and Type 2 Diabetes.

OBJECTIVE: To quantify and contextualize the risk for coronavirus disease 2019 (COVID-19)-related hospitalization and illness severity in type 1 diabetes. RESEARCH DESIGN AND METHODS: We conducted a prospective cohort study to identify case subjects with COVID-19 across a regional health care network of 137 service locations. Using an electronic health record query, chart review, and patient contact, we identified clinical factors influencing illness severity. RESULTS: We identified COVID-19 in 6,138, 40, and 273 patients without diabetes and with type 1 and type 2 diabetes, respectively. Compared with not having diabetes, people with type 1 diabetes had adjusted odds ratios of 3.90 (95% CI 1.75-8.69) for hospitalization and 3.35 (95% CI 1.53-7.33) for greater illness severity, which was similar to risk in type 2 diabetes. Among patients with type 1 diabetes, glycosylated hemoglobin (HbA1c), hypertension, race, recent diabetic ketoacidosis, health insurance status, and less diabetes technology use were significantly associated with illness severity. CONCLUSIONS: Diabetes status, both type 1 and type 2, independently increases the adverse impacts of COVID-19. Potentially modifiable factors (e.g., HbA1c) had significant but modest impact compared with comparatively static factors (e.g., race and insurance) in type 1 diabetes, indicating an urgent and continued need to mitigate severe acute respiratory syndrome coronavirus 2 infection risk in this community.

Effects of a Tailored Text Messaging Intervention Among Diverse Adults With Type 2 Diabetes: Evidence From the 15-Month REACH Randomized Controlled Trial.

OBJECTIVE: Text messaging interventions have high potential for scalability and for reductions in health disparities. However, more rigorous, long-term trials are needed. We examined the long-term efficacy and mechanisms of a tailored text messaging intervention. RESEARCH DESIGN AND METHODS: Adults with type 2 diabetes participated in a parallel-groups, 15-month randomized controlled trial and were assigned to receive Rapid Education/Encouragement and Communications for Health (REACH) for 12 months or control. REACH included interactive texts and tailored texts addressing medication adherence and nontailored texts supporting other self-care behaviors. Outcomes included hemoglobin A1c (HbA1c), diabetes medication adherence, self-care, and self-efficacy. RESULTS: Participants (N = 506) were approximately half racial/ethnic minorities, and half were underinsured, had annual household incomes <$35,000, and had a high school education or less; 11% were homeless. Average baseline HbA1c was 8.6% ± 1.8%; 70.0 ± 19.7 mmol/mol) with n = 219 having HbA1c ≥8.5% (69 mmol/mol). Half were prescribed insulin. Retention was over 90%. Median response rate to interactive texts was 91% (interquartile range 75%, 97%). The treatment effect on HbA1c at 6 months (-0.31%; 95% CI -0.61%, -0.02%) was greater among those with baseline HbA1c ≥8.5% (-0.74%; 95% CI -1.26%, -0.23%), and there was no evidence of effect modification by race/ethnicity or socioeconomic disadvantage. REACH improved medication adherence and diet through 12 months and self-efficacy through 6 months. Treatment effects were not significant for any outcome at 15 months. REACH reduced barriers to adherence, but barrier reduction did not mediate outcome improvements. CONCLUSIONS: REACH engaged at-risk patients in diabetes self-management and improved short-term HbA1c. More than texts alone may be needed to sustain the effects.