Supporting Engagement, Adherence, and Behavior Change in Online Dietary Interventions

Abstract

Introduction

Poor diet is a leading cause of death and disease globally. This epidemic requires effective and accessible interventions to stop the increasing number of diet-related deaths and the health and economic impacts of diet-related disease. Online interventions provide flexibility and accessibility. With the ubiquitous use of smartphones, they can be intertwined with daily activities such as shopping and eating. The aim of this review is to determine what features and behavior change techniques employed in online dietary interventions for adult populations promoting dietary behavior change.

Methods

The researchers conducted a systematic search of Cumulative Index of Nursing and Allied Health, Cochrane Library, Global Health, MEDLINE, PsychINFO, and psychological and behavioral sciences electronic bibliography databases, and specialist electronic health (e-health) journals from database inception to January, 2018. Studies were included if they were randomized controlled trials of online dietary interventions with active comparator conditions in adult populations, and with reported dietary change measures. A quality score was applied to each study calculated by a developed scoring system. The review analyzed intervention dietary change measures, attrition (nonuse and dropout), engagement (metrics and intensity of use), adherence (defined as compliance to the treatment protocol), behavior change techniques employed to achieve dietary change, and techniques employed in successful (those who achieved significant results in the targeted dietary behavior) vs unsuccessful interventions as reported by the studies.

Results

A total of 21 studies composed of a total of 7,455 adults and reporting on 19 different e-health interventions were included from 1,237 records. These studies targeted dietary change as measured by reduced energy intake (5) or changes in specific dietary components (15) and overall diet quality (4). Dietary change was a behavior target in general healthy populations (12) and for managing diseases such as obesity and cardiovascular disease (7), or for improving quality of life for those with chronic conditions (1). Improvements in dietary behavior were seen in 14 of the 19 interventions reported.

Discussion

The results suggest that online interventions can be successful in achieving dietary behavior change across a range of defined populations. However, disparate reporting of engagement and limited reporting of nonuse attrition rates limited the analysis of which behavior change techniques were most effective in achieving this change.

Implications for Research and Practice

The results of this review support the potential of online and smartphone dietary interventions as a method to achieve change in diet in defined populations. However, further work needs to be done in examining how users engage with interventions, and thus which behavior change techniques are most effective.

Introduction

Poor diet is the leading cause of preventable death, resulting in 1 in 5 deaths globally.¹ It is a well-established risk factor for chronic conditions and noncommunicable diseases such as obesity and cardiovascular disease as well as common mental disorders (depression and anxiety). Conversely, specific positive dietary patterns such as the Mediterranean diet have been associated epidemiologically with protective health effects.² Behavioral interventions aim to change health by targeting particular behaviors.³ They can be effective in changing eating behaviors, particularly when using multiple behavior change techniques (BCTs).⁴ These particular techniques are used in these interventions based on psychological theories of the determinants of behavior. In 2013, Michie et al⁵ published a hierarchal taxonomy of BCTs to standardize definitions of commonly applied BCTs.

Achieving dietary improvement with effective online behavioral interventions at a population level could reduce the global burden of disease. The potential benefits of delivering behavioral interventions online include reach, accessibility, scalability, and cost-effectiveness.6, 7 Searching for health information remains 1 of the most widely employed uses of the Internet, and searches for diet and nutrition are universally popular.⁸ Data from the US, Canada, Norway, and Australia show that the Internet is the most popular source of dietary and nutrition information among adult populations.9, 10, 11, 12

Internet and smartphone (e-health and mobile health) technologies may be particularly useful as health interventions because they can be seamlessly integrated into daily activities.6, 7, 13, 14 In relation to diet, this could mean users accessing intervention content or activities while shopping, cooking, or dining out. Communication technologies also increase opportunities to send reminders and notifications to participants to aid adherence to interventions.7, 15

However, online and smartphone-based interventions can be limited in their ability to engage and retain participants; high attrition is a well-recognized issue in the field.16, 17, 18 High attrition rates often affect the ability to assess the efficacy and effectiveness of online interventions. Metrics of the success of online interventions need to include uptake, accessibility, and robust estimates of “effective engagement.”⁷ In e-health literature, engagement was traditionally measured by simple usage metrics such as module completion with little analysis of how users interacted with the intervention. Studies tended to analyze attrition, which was often counted as when a user had not completed a required measure, independent of the intervention content. Previous online interventions required further evaluation to determine their effectiveness among the target demographic, to understand which strategies worked best for enhancing user engagement and to determine requisite levels of engagement for optimal outcomes. In particular, understanding what works, and how, is essential to inform future interventions aiming to change dietary behaviors.

Previous systematic reviews examined the effectiveness of online dietary Internet interventions as part of a broader review of Internet health behavior interventions¹⁹ and computer tailored dietary interventions,20, 21 specific types of online dietary interventions such as adaptive electronic learning,²² or the effectiveness of computer-based dietary or lifestyle interventions in specific populations such as interventions targeted at obesity and diabetes.²³ Those reviews examined literature up to 2011. To date, there have been no systematic reviews specifically investigating randomized control trials (RCTs) of Internet-based dietary interventions across content approaches (nontailored or tailored) and with active comparator conditions.

The aim of this systematic review was to identify existing studies examining the efficacy or effectiveness of online dietary interventions against active controls, user engagement, and adherence, and the behavior change techniques employed to achieve dietary behavior change. In particular, the review aimed to identify the features or designs that were successful in achieving dietary behavior change.