Digital interventions to promote vaccine uptake among older adults: A systematic review and network meta-analysis

To systematically evaluate the effect of digital intervention on improving routine vaccination in the elderly and to conduct a comparative analysis of different intervention modalities using network meta-analysis (NMA).

PubMed, Web of Science, The Cochrane Library, Embase, Scopus, CINAHL, and WanFang Data were searched for randomized controlled trials (RCTs) using digital interventions to promote vaccination in older populations from inception to 15 June 2024. We performed a final update of the literature search in May 2025; no additional eligible studies were identified. Two researchers independently screened the literature, extracted data, and assessed the risk of bias in the included studies, and an NMA was performed using RevMan 5.4 and R Studio, PROSPERO Registration Number: CRD42024527483.

Eleven RCTs were included. The traditional meta-analysis demonstrated a small but statistically significant increase in influenza vaccination rates (RR = 1.01, 95% CI [1.01, 1.01], P < 0.00001), accompanied by substantial heterogeneity (I ² = 86%). Pneumococcal vaccine uptake was significantly enhanced (RR = 1.11, 95% CI [1.03, 1.18], P < 0.01), with moderate heterogeneity (I ² = 46%). The single study on the herpes zoster vaccine reported a statistically significant effect, whereas COVID-19 vaccine reminder interventions showed no significant efficacy. In the NMA, video-based interventions ranked first based on the surface under the cumulative ranking curve, but all pairwise comparisons between different intervention modes crossed the null value.

Digital interventions show a significant, yet highly heterogeneous, positive impact on vaccination rates in older adults. While video-based education showed the highest ranking probability, the current evidence is insufficient to conclude that any specific digital modality is statistically superior to others. Due to the limited included studies, the findings need to be supplemented by more high-quality studies. Future research should focus on newer digital technologies to help the older population keep up with the "digital intelligence era."