Effects of Using Websites on Physical Activity and Diet Quality for Adults Living With Chronic Health Conditions: Systematic Review and Meta-Analysis

BACKGROUND: Adults with chronic health conditions need support to manage modifiable risk factors such as physical inactivity and poor diet. Disease-specific websites with health information on physical activity and diet quality may be effective in supporting adults in managing their chronic illnesses. OBJECTIVE: The primary aim of this review was to determine whether using websites with health information can lead to improvements in physical activity levels or diet quality in adults with chronic health conditions. METHODS: Randomized controlled trials evaluating the effectiveness of website use on levels of physical activity or diet quality in adults with chronic health conditions were included. MEDLINE, Embase, CINAHL, and the Physiotherapy Evidence Database were searched from the earliest available record until February 2023. Data for outcomes measuring physical activity levels; diet quality; and, where reported, self-efficacy and quality of life were independently extracted by 2 reviewers. The risk of bias was assessed using the Physiotherapy Evidence Database scale, and the overall certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. Where values were presented as the same unit of measure, postintervention scores were pooled for meta-analysis to yield an overall mean difference (MD). A standardized MD (SMD) was calculated for the pooled data in which different units for the same outcome were used. Individual trial data were described in cases where the data of trials could not be pooled. RESULTS: A total of 29 trials (N=6418 participants) across 8 different disease groups with intervention periods ranging from 4 weeks to 12 months were included in the analysis. There was moderate-certainty evidence that using websites with health information increased levels of moderate to vigorous physical activity (MD=39 min/wk, 95% CI 18.60-58.47), quality of life (SMD=0.36, 95% CI 0.12-0.59), and self-efficacy (SMD=0.26, 95% CI 0.05-0.48) and high-certainty evidence for reduction in processed meat consumption (MD=1.1 portions/wk, 95% CI 0.70-1.58) when compared with usual care. No differences were detected in other measures of diet quality. There was no increased benefit for website users who were offered additional support. CONCLUSIONS: The use of websites for risk factor management has the potential to improve physical activity levels, quality of life, and self-efficacy as well as reduce processed meat consumption for adults living with chronic health conditions when compared with usual care. However, it remains unclear whether using websites leads to meaningful and long-lasting behavior change. TRIAL REGISTRATION: PROSPERO CRD42021283168; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=283168