Brann, MariaMadsen, Emilie RefsbolHead, Katharine J.Longtin, KristaYeager, Valerie A.2024-08-152024-08-152024-07https://hdl.handle.net/1805/42798Previously considered a disease that afflicted adults over the age of 45, Type 2 diabetes has become a major health problem for younger age groups in recent decades, specifically young adults. The disease is often attributed to lifestyle choices, such as poor diet and inactivity. Conversely, lifestyle choices can contribute to improvement in its management and subsequent health outcomes. Through multiple research phases, I developed and employed instructional text messages to support diet management in young adults (18-45) with Type 2 diabetes. This study aimed to address the effectiveness of instructional text messages in increasing self-efficacy, health literacy, and dietary adherence over standard of care text messages in young adults with Type 2 diabetes over a two-week intervention period. The study design involved a two-arm text message intervention (comparison and intervention), wherein participants received daily text messages about diet. Formative research for the development of instructional text messages included expert interviews and panels, cognitive interviews, and pre-testing. Prior to, and following, the intervention, participants completed scales assessing health literacy, self-efficacy, and diet adherence, and responded to open-ended questions. Eighty-five participants enrolled in the intervention. I analyzed quantitative data using repeated measures ANOVAs and qualitative data using a priori and thematic analysis. Quantitative results indicated no statistically significant effect of instructional text messages over standard of care text messages in increasing health literacy, self-efficacy, and diet adherence. However, findings illustrate a remarkable main effect from receiving text messages on self-efficacy, suggesting that receiving text messages, regardless of design, may support increased self-efficacy in young adults with Type 2 diabetes. Qualitative data showed a sizable number of intervention group participants emphasized the value of the instructional design in offering actionable steps and behaviors to engage with. Most recommendations for message improvements were noted by the comparison group, many of which were implemented in the instructional messages, supporting the use of instructional design to produce engagement and behavior change. Implications of this study reflect the novel implementation of instructional design to support diet management in Type 2 diabetics and the uses of health literacy and self-efficacy to inform and evaluate diet-oriented communication interventions.en-USdiet adherencehealth communicationhealth literacyinstructional messagingself-efficacyType 2 diabetes interventionDissertation