JMIR Publications

ABSTRACT

Background:

Noncommunicable diseases (NCDs) cause a very significant health and economic burden. As they are associated with modifiable behavioral risk factors such as physical inactivity and poor diet, more evidence on effective health behavior modification methods is needed. Fully online delivery of clinical trials can provide a practical and scalable way to evaluate interventions that aim to modify relevant lifestyle factors. The emergence of online delivery methods presents opportunities and challenges that need to be better understood to inform future research.

Objective:

This umbrella scoping review aimed to summarize current evidence on the opportunities and challenges provided by lifestyle intervention clinical trials that are delivered fully online.

Methods:

Evidence was synthesized from existing peer-reviewed review papers to map the digital delivery methods in online lifestyle intervention trials, focusing on technologies, recruitment, engagement and retention strategies, and reported strengths, limitations, and future directions. Using PRISMA-ScR guidelines, PubMed, EMBASE, CINAHL, Web of Science, and Scopus were searched for reviews published between January 2013 and May 2025. Predominantly (>50%) hybrid, telehealth, or acute condition focused interventions were excluded.

Results:

Eligible reviews (n=39) discussed digital interventions targeting diet, physical activity, or both, for lifestyle improvement, chronic disease prevention or management. The most common hardware used in online lifestyle clinical trials were smartphones and wearables, with the most frequent software modes being web-based platforms, mobile apps, and SMS. Successful engagement strategies often integrated behavior changes techniques, such as goal setting, self-monitoring, personalized feedback, and human support into the intervention design, or had behavior change techniques as a feature of the technology itself. Reported strengths of conducting clinical trials online included improved accessibility, scalability, cost-efficiency and personalization, whereas limitations discussed were poor engagement and retention, digital literacy barriers, and rapid technological change outpacing evaluation capabilities. Interventions that used theory-based designs, particularly those using Social Cognitive Theory, the Transtheoretical Model, and the Theory of Planned Behavior, were reportedly most successful in improving behavioral outcomes. Engagement and retention varied considerably across online trials, suggesting that the success of these studies may depend less on the online delivery modality itself and more on how interventions and technologies are designed, including the integration of behavioral theory and behavior change techniques.

Conclusions:

This review shows that online delivery of lifestyle intervention trials is a feasible and potentially advantageous method as it can improve reach, increase scalability, be cost-efficient, and allow more personalization of the intervention. To further improve the conduct of online clinical trials, future research should address increased use of behavioral change theory, equitable access to clinical trial participation, management of data privacy and security, intervention fidelity, and use of novel technologies such as artificial intelligence in a field that is rapidly evolving. Clinical Trial: The protocol was prospectively registered with the Open Science Framework https://osf.io/umcfv; 5 September 2023