Patient engagement with an automated postdischarge text messaging program for improving care transitions.

Automated text messaging is a promising approach to monitor patients after hospital discharge and avert readmissions; however, it is not known to what extent patients would engage with this type of program and whether engagement may vary based on patients' characteristics. Using data from a 30-day postdischarge texting program at a large university hospital, we examined engagement over time (operationalized as response rate to text messages) and patient characteristics associated with engagement. Of the 1324 patients in the study sample, 838 (63%) stayed in the program for the full duration. Among those retained, the median response rate was 33% (interquartile range: 11%-77%) and decreased over time. Patients who were male (p < .05), were Black/African American (p < .001), had lower health literacy (p < .01), or had not recently logged into the patient portal (p < .001), all had lower response rates. Results support closer examinations of patient engagement in hospital-based texting programs and who is positioned to benefit.

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.

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.

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.

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.

Family Typology for Adults With Type 2 Diabetes: Longitudinal Stability and Validity for Diabetes Management and Well-being.

OBJECTIVE: We validated longitudinally a typology of diabetes-specific family functioning (named Collaborative and Helpful, Satisfied with Low Involvement, Want More Involvement, and Critically Involved) in adults with type 2 diabetes. RESEARCH DESIGN AND METHODS: We conducted k-means cluster analyses with nine dimensions to determine if the typology replicated in a diverse sample and if type assignment was robust to variations in sampling and included dimensions. In a subsample with repeated assessments over 9 months, we examined the stability and validity of the typology. We also applied a multinomial logistic regression approach to make the typology usable at the individual level, like a diagnostic tool. RESULTS: Participants (N = 717) were 51% male, more than one-third reported minority race or ethnicity, mean age was 57 years, and mean hemoglobin A1c (HbA1c) was 7.9% (63 mmol/mol; 8.7% [72 mmol/mol] for the longitudinal subsample). The typology was replicated with respect to the number of types and dimension patterns. Type assignment was robust to sampling variations (97% consistent across simulations). Type had an average 52% stability over time within participants; instability was not explained by measurement error. Over 9 months, type was independently associated with HbA1c, diabetes self-efficacy, diabetes medication adherence, diabetes distress, and depressive symptoms (all P < 0.05). CONCLUSIONS: The typology of diabetes-specific family functioning was replicated, and longitudinal analyses suggest type is more of a dynamic state than a stable trait. However, type varies with diabetes self-management and well-being over time as a consistent independent indicator of outcomes. The typology is ready to be applied to further precision medicine approaches to behavioral and psychosocial diabetes research and care.

Empowering patients to address diabetes care gaps: formative usability testing of a novel patient portal intervention.

Objective: The aim of this study was to design and assess the formative usability of a novel patient portal intervention designed to empower patients with diabetes to initiate orders for diabetes-related monitoring and preventive services. Materials and Methods: We used a user-centered Design Sprint methodology to create our intervention prototype and assess its usability with 3 rounds of iterative testing. Participants (5/round) were presented with the prototype and asked to perform common, standardized tasks using think-aloud procedures. A facilitator rated task performance using a scale: (1) completed with ease, (2) completed with difficulty, and (3) failed. Participants completed the System Usability Scale (SUS) scored 0-worst to 100-best. All testing occurred remotely via Zoom. Results: We identified 3 main categories of usability issues: distrust about the automated system, content concerns, and layout difficulties. Changes included improving clarity about the ordering process and simplifying language; however, design constraints inherent to the electronic health record system limited our ability to respond to all usability issues (eg, could not modify fixed elements in layout). Percent of tasks completed with ease across each round were 67%, 60%, and 80%, respectively. Average SUS scores were 87, 74, and 93, respectively. Across rounds, participants found the intervention valuable and appreciated the concept of patient-initiated ordering. Conclusions: Through iterative user-centered design and testing, we improved the usability of the patient portal intervention. A tool that empowers patients to initiate orders for disease-specific services as part of their existing patient portal account has potential to enhance the completion of recommended health services and improve clinical outcomes.

Family involvement and diabetes distress across dyads for adults with type 2 diabetes.

OBJECTIVE: Family/friend involvement and diabetes distress are associated with outcomes for persons with type 2 diabetes (PWDs), but little is known about how they relate to each other. We aim to (1) describe associations between PWD and support person (SP) distress; (2) describe associations between involvement and diabetes distress for PWDs, for SPs, and across the dyad; and (3) explore whether associations differ by PWD-SP cohabitation. METHODS: PWDs and SPs co-enrolled in a study evaluating the effects of a self-care support intervention and completed self-report measures at baseline. RESULTS: PWDs and SPs (N = 297 dyads) were, on average, in their mid-50s and around one-third identified as racial or ethnic minorities. The association between PWD and SP diabetes distress was small (Spearman's ρ = 0.25, p < 0.01). For PWDs, experienced harmful involvement from family/friends was associated with more diabetes distress (standardized ß = 0.23, p < 0.001) independent of helpful involvement in adjusted models. Separately, SPs' self-reported harmful involvement was associated with their own diabetes distress (standardized ß = 0.35, p < 0.001) and with PWDs' diabetes distress (standardized ß = 0.25, p = 0.002), independent of SPs' self-reported helpful involvement. CONCLUSION AND PRACTICE IMPLICATIONS: Findings suggest dyadic interventions may need to address both SP harmful involvement and SP diabetes distress, in addition to PWD distress.

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.

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.

BOUNDING THE LOCAL AVERAGE TREATMENT EFFECT IN AN INSTRUMENTAL VARIABLE ANALYSIS OF ENGAGEMENT WITH A MOBILE INTERVENTION.

Estimation of local average treatment effects in randomized trials typically relies upon the exclusion restriction assumption in cases where we are unwilling to rule out the possibility of unmeasured confounding. Under this assumption, treatment effects are mediated through the post-randomization variable being conditioned upon, and directly attributable to neither the randomization itself nor its latent descendants. Recently, there has been interest in mobile health interventions to provide healthcare support. Mobile health interventions such as the Rapid Encouragement/Education and Communications for Health (REACH), designed to support self-management for adults with type 2 diabetes, often involve both one-way and interactive messages. In practice, it is highly likely that any benefit from the intervention is achieved both through receipt of the intervention content and through engagement with/response to it. Application of an instrumental variable analysis in order to understand the role of engagement with REACH (or a similar intervention) requires the traditional exclusion restriction assumption to be relaxed. We propose a conceptually intuitive sensitivity analysis procedure for the REACH randomized trial that places bounds on local average treatment effects. Simulation studies reveal this approach to have desirable finite-sample behavior and to recover local average treatment effects under correct specification of sensitivity parameters.

A 3-Item Measure of Digital Health Care Literacy: Development and Validation Study.

BACKGROUND: With increased reliance on digital health care, including telehealth, efficient and effective ways are needed to assess patients' comfort and confidence with using these services. OBJECTIVE: The goal of this study was to develop and validate a brief scale that assesses digital health care literacy. METHODS: We first developed an item pool using existing literature and expert review. We then administered the items to participants as part of a larger study. Participants were caregivers of children receiving care at a pediatric clinic who completed a survey either on the web or over the telephone. We randomized participants into development and confirmatory samples, stratifying by language so that exploratory factor analysis and confirmatory factor analysis could be performed with separate samples of participants. We assessed the scale's validity by examining its associations with participants' demographics, digital access, and prior digital health care use. RESULTS: Participants (N=508) were, on average, aged 34.7 (SD 7.7) years, and 89.4% (454/508) were women. Of the 508 participants, 280 (55.1%) preferred English as their primary language, 157 (30.9%) preferred Spanish, and 71 (14%) preferred Arabic; 228 (45%) had a high school degree or less; and 230 (45.3%) had an annual household income of

Feasibility and Short-Term Effects of a Multi-Component Emergency Department Blood Pressure Intervention: A Pilot Randomized Trial.

Background Emergency department (ED) visits can be opportunities to address uncontrolled hypertension. We sought to compare short-term blood pressure measures between the Vanderbilt Emergency Room Bundle (VERB) intervention and usual care plus education. Methods and Results We conducted a randomized trial of 206 adult patients with hypertension and elevated systolic blood pressure (SBP) presenting to 2 urban emergency departments in Tennessee, USA. The VERB intervention included educational materials, a brief motivational interview, pillbox, primary care engagement letter, pharmacy resources, and 45 days of informational and reminder text messages. The education arm received a hypertension pamphlet. After 78 participants were enrolled, text messages requested confirmation of receipt. The primary clinical outcome was 30-day SBP. The median 30-day SBP was 122 and 126 mm Hg in the VERB and education arms, respectively. We estimated the mean 30-day SBP to be 3.98 mm Hg lower in the VERB arm (95% CI, -2.44 to 10.4; P=0.22). Among participants enrolled after text messages were adapted, the respective median SBPs were 121 and 130 mm Hg, and we estimated the mean 30-day SBP to be 8.57 mm Hg lower in the VERB arm (95% CI, 0.98‒16.2; P=0.027). In this subgroup, the median response rate to VERB text messages was 56% (interquartile range, [26%‒80%]). Conclusions This pilot study demonstrated feasibility and found an improvement in SBP for the subgroup for whom interactive messages were featured. Future studies should evaluate the role of interactive text messaging as part of a comprehensive emergency department intervention to improve blood pressure control. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02672787.

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.

User preferences for and engagement with text messages to support antihypertensive medication adherence: Findings from a pilot study evaluating an emergency department-based behavioral intervention.

OBJECTIVE: We examined users' preferences for and engagement with text messages delivered as part of an emergency department (ED)-based intervention to improve antihypertensive medication adherence. METHODS: We recruited ED patients with elevated blood pressure for a pilot randomized trial evaluating a medication adherence intervention with text messages. Intervention participants chose text content and frequency, received texts for 45 days, and completed a feedback survey. We defined engagement via responses to texts. We examined participant characteristics associated with text preferences, engagement, and feedback. RESULTS: Participants (N = 101) were 57% female and 46% non-White. Most participants (71%) chose to receive both reminder and informational texts; 94% chose reminder texts once per day and 97% chose informational texts three times per week. Median text message response rate was 56% (IQR 26-80%). Participants who were Black (p < 0.01), had lower income (p = 0.03), or had lower medication adherence (p < 0.01) rated the program as more helpful and wanted additional functionalities for adherence support. CONCLUSIONS AND PRACTICE IMPLICATIONS: While overall engagement was modest, participants at risk of worse health outcomes expressed more value and interest in the program. Findings inform the design of text messaging interventions for antihypertensive medication adherence and support targeting vulnerable patients to reduce health disparities. CLINICAL TRIALS REGISTRATION: NCT02672787.

Changes in family involvement occasioned by FAMS mobile health intervention mediate changes in glycemic control over 12 months.

Mobile phone-delivered interventions have proven effective in improving glycemic control (HbA1c) in the short term among adults with type 2 diabetes (T2D). Family systems theory suggests engaging family/friend in adults' diabetes self-care may enhance or sustain improvements. In secondary analysis from a randomized controlled trial (N = 506), we examined intervention effects on HbA1c via change in diabetes-specific helpful and harmful family/friend involvement. We compared a text messaging intervention that did not target family/friend involvement (REACH), REACH plus family-focused intervention components targeting helpful and harmful family/friend involvement (REACH + FAMS), and a control condition. Over 6 months, both intervention groups experienced improvement in HbA1c relative to control, but at 12 months neither did. However, REACH + FAMS showed an indirect effect on HbA1c via change in helpful family/friend involvement at both 6 and 12 months while REACH effects were not mediated by family/friend involvement. Consistent with family systems theory, improvements in HbA1c mediated by improved family/friend involvement were sustained.

Estimating the impact of engagement with digital health interventions on patient outcomes in randomized trials.

OBJECTIVE: Guidance is needed on studying engagement and treatment effects in digital health interventions, including levels required for benefit. We evaluated multiple analytic approaches for understanding the association between engagement and clinical outcomes. MATERIALS AND METHODS: We defined engagement as intervention participants' response rate to interactive text messages, and considered moderation, standard regression, mediation, and a modified instrumental variable (IV) analysis to investigate the relationship between engagement and clinical outcomes. We applied each approach to two randomized controlled trials featuring text message content in the intervention: REACH (Rapid Encouragement/Education and Communications for Health), which targeted diabetes, and VERB (Vanderbilt Emergency Room Bundle), which targeted hypertension. RESULTS: In REACH, the treatment effect on hemoglobin A1c was estimated to be -0.73% (95% CI: [-1.29, -0.21]; P = 0.008), and in VERB, the treatment effect on systolic blood pressure was estimated to be -10.1 mmHg (95% CI: [-17.7, -2.8]; P = 0.007). Only the IV analyses suggested an effect of engagement on outcomes; the difference in treatment effects between engagers and non-engagers was -0.29% to -0.51% in the REACH study and -1.08 to -3.25 mmHg in the VERB study. DISCUSSION: Standard regression and mediation have less power than a modified IV analysis, but the IV approach requires specification of assumptions. This is the first review of the strengths and limitations of various approaches to evaluating the impact of engagement on outcomes. CONCLUSIONS: Understanding the role of engagement in digital health interventions can help reveal when and how these interventions achieve desired outcomes.

Adults with type 2 diabetes benefit from self-management support intervention regardless of depressive symptoms.

AIMS: Elevated depressive symptoms are common among adults with type 2 diabetes (T2D). In a secondary analysis from an RCT of a diabetes self-management support intervention that did not target depressive symptoms, we sought to determine if depressive symptoms were reduced by the intervention (i.e., depressive symptoms an outcome) or, alternatively, if intervention effects on hemoglobin A1c were lesser among persons with clinically elevated depressive symptoms (i.e., depressive symptoms an effect modifier). METHODS: We evaluated a text messaging intervention, REACH, in a diverse (half non-white, half underinsured) sample of N = 506 adults with T2D. Participants completed the Patient Health Questionnaire-8 (PHQ) and A1c tests at baseline and 6 months. We conducted a factor analysis to identify somatic- and cognitive-affective symptoms on the PHQ. We tested our hypotheses with regression models, using interaction terms and subgroup analyses. RESULTS: REACH improved depressive symptoms among participants with lower baseline A1c (<8.5%; ß = -0.133, p = .007; cognitive ß = -0.107, p = .038; somatic ß = -0.131, p = .014) but not among participants with higher baseline A1c (≥8.5%; ß = 0.040, p = .468). Baseline depressive symptoms did not modify the effect on A1c. CONCLUSIONS: We found support for the hypothesis that depressive symptoms - both somatic- and cognitive-affective - may be an outcome, rather than an effect modifier, of effective diabetes self-management support interventions.

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.