Optimizing a standalone text messaging-based weight loss intervention

我们提议的项目的总体目标是开发一种有效的独立短信肥胖 干预。我们专注于独立的方法--可以完全通过短信发送的治疗方法 --因为它们的传播潜力。独立的处理很容易扩展，可以模块化使用， 几个这样的干预措施(例如，Text4Baby)已经实现了人口覆盖。尽管他们的翻译 潜在的，还没有试验测试完全独立的短信干预减肥。要做到这一点 目标，我们建议使用多阶段优化策略(MOST)来确定哪些干预措施 组件应该包括在我们的独立短信减肥干预的最佳选择。大多数指南都是 干预成分的随机实验，以便我们可以组装治疗方案 只含有对减肥有重大影响的成分。我们将进行为期12个月的 在592名肥胖成年人中进行的实验研究。所有研究参与者将接受为期6个月的核心减肥 短信干预(基于我们的IOTA方法)，包括量身定制的行为改变目标、交互式 自我监控、自动反馈和技能培训。使用部分析因设计，我们将随机化 参与者参加了16个实验条件之一(每个条件37个)，这些条件将测试短信 构件(和标高)。我们将在1、3、6和12个月跟踪参与者。我们将在实验中 确定哪些文本消息传递组件(和组件级别)对6- 每月体重变化和6个月饮食、体力活动的变化，以及 在6个月内减重5%，在12个月内保持体重。我们将研究以下关联 参与度和非使用量损耗与权重变化、参与度和非使用率变化的模型轨迹 随时间推移的使用损耗，并测试理论驱动的敬业度、自我效能感和 技术接受模型结构：感知的易用性和感知的有用性。我们还将 确定实施干预措施的成本及其增量成本效益。最后，我们 探讨干预组件的组合是否因参与者不同而效果不同 这将使我们能够最终调整干预结构，以获得最佳结果。这项研究将 演示如何最好地组装低成本、高覆盖率的独立短信减肥干预措施。

The overarching goal of our proposed project is to develop an efficacious standalone text messaging obesity intervention. We focus on standalone approaches -- treatments that can be wholly delivered via text messaging -- because of their dissemination potential. Standalone treatments are readily scalable, can be used modularly, and several such interventions (e.g., Text4baby) have achieved population reach. Despite their translational potential, no trials have yet tested a fully standalone texting intervention for weight loss. To accomplish this goal, we propose to use the multiphase optimization strategy (MOST) to identify which intervention components should optimally be included in our standalone texting weight loss intervention. MOST guides the randomized experimentation of intervention components so that we might assemble a treatment package comprised only of components that make a meaningful impact on weight loss. We will conduct a 12-month experimental trial among 592 obese adults. All study participants will receive a core 6-month weight loss texting intervention (based on our iOTA approach) that includes tailored behavior change goals, interactive self-monitoring, automated feedback, and skills training. Using a fractional factorial design, we will randomize participants to one of 16 experimental conditions (37 in each condition) that will test the text messaging components (and levels). We will follow participants at months 1, 3, 6, and 12. We will experimentally determine which text messaging components (and component levels) produce a meaningful contribution to 6- month weight change and 6-month change in diet, physical activity, and the proportion of participants who achieve > 5% weight loss at 6 months and maintenance at 12 months. We will examine associations of engagement and non-usage attrition with weight change, model trajectories of change in engagement and non- usage attrition over time, and test theoretically-driven mediators of engagement, self-efficacy, and the Technology Acceptance Model constructs: perceived ease of use and perceived usefulness. We will also determine the cost of the intervention’s implementation and its incremental cost effectiveness. Finally, we explore whether combinations of intervention component are differentially efficacious by participant characteristics; this will allow us to ultimately tailor intervention structures for optimal outcomes. This study will demonstrate how to best assemble a low cost, high reach standalone texting weight loss intervention.