JMIR Publications

ABSTRACT

Background:

Digital health interventions are increasingly being used as supplements or replacements for face-to-face services, as a part of predictive prevention. They may be offered to NHS Health Check patients whose cardiovascular risk scores suggest a need to improve diet, increase physical activity, stop smoking or reduce alcohol consumption. Despite their popularity, little is known about their effectiveness.

Objective:

To summarise the effectiveness of digital interventions at improving behavioural and health outcomes related to physical activity, smoking, alcohol or diet. To identify differences in effectiveness between modes of delivery of digital interventions.

Methods:

Eligibility criteria: English language articles published between 01 January 2009 and 25 February 2019 that presented: i) a narrative review or meta-analysis of any study design examining digital intervention effectiveness; ii) data related to adults (≥18 years) in high-income countries; iii) data on behavioural or health outcomes related to the NHS Health Check programme. Any timeframe or comparators were eligible. Information sources: MEDLINE, Embase, PsycINFO, Cochrane Reviews and grey literature. Risk of bias: The AMSTAR 2 tool was used to assess review confidence ratings.

Results:

Included studies: 93 reviews from the academic literature (47 with meta-analysis) and 2 grey literature items were included. Synthesis of results: Digital interventions were typically more effective than no intervention, but effect sizes were small. Evidence on the effectiveness of digital interventions compared to face-to-face interventions was mixed. Most trials reported intent-to-treat analysis and attrition rates were often high. Studies with long follow-ups were scarce. However, it seems that digital interventions may be effective for up to 6 months after the end of the intervention, but that effects have dissipated? by twelve months after. Description of effect: There were small positive effects on smoking cessation and alcohol reduction, and possible effectiveness in combined diet and physical activity interventions. No effect was observed for other behavioural categories.

Conclusions:

Digital interventions can have small positive effects in smoking, alcohol, and combined diet and physical activity interventions. We cannot know if small effects are due to low effectiveness of treatment or to non-adherence. In addition, our ability to make inferences from the literature we reviewed is limited because interventions that were reviewed were heterogeneous; many reviews had critically low AMSTAR 2 ratings; analysis was typically intent-to-treat; and follow-up times were relatively short. Limitations of our review include: that we did not do full hand searches or consult experts to ensure we found all reviews; that individual studies might have been double counted, if they were surveyed in two reviews. Clinical Trial: Funding: Public Health England Registration: PROSPERO CRD42019126074.