Rheumatology advances in practice;
Objective: The aim of this systematic review was to assess the evidence from randomized controlled trials (RCTs) and cohort studies for the effectiveness of digital interventions designed to enhance adherence to physical activity (PA) for people with inflammatory arthritis and describe the intervention content using established coding criteria. Methods: Six electronic databases were searched for published and unpublished studies. Independent data extraction and quality assessment (Cochrane risk of bias II or ROBINS-I) were conducted by two reviewers. The primary outcome was self-reported adherence to PA post-intervention. Secondary outcomes included self-reported adherence to PA at other time points, level of PA or engagement with intervention at any follow-up time point. Intervention content was assessed using the Consensus on Exercise Reporting Template and the Behaviour Change Techniques Taxonomy version 1. Results: From 11 136 citations, four moderate risk of bias studies (three RCTs and one cohort study) including 1160 participants with RA or JIA were identified. Owing to heterogeneity of outcomes, a narrative synthesis was conducted. Only one RCT reported a small between-group difference in adherence to PA [mean difference (95% CI) -0.46 (-0.82, -0.09)] in favour of the intervention. There were no between-group differences in any secondary outcomes. Interventions included between 3 and 11 behaviour change techniques but provided minimal information on exercise prescription. Conclusion: There is currently limited moderate-quality evidence available to provide confident evaluation of the effect of web-based and mobile health interventions on adherence to PA or level of PA post-intervention in people with inflammatory arthritis.