Does social media promotion influence citation counts? A long-term follow-up to a randomised trial in a general neurosurgical journal

Social media promotion has become mainstream for neurosurgical publications. Any effect of promotion on citation counts would significantly influence academia and is currently not well-studied. We previously reported that structured social media promotion of neurosurgical articles had no significant effect on citation counts, website visits, or PDF downloads at one- and two-years post promotion. In this study, we assess whether a longer follow-up period has altered these previously reported results, since citation counts typically follow a Poisson-like distribution, increasing gradually and often peaking several years after publication. We followed up the original 177 articles published in Acta Neurochirurgica between May and September 2020 which were randomised either to the social media intervention (single Twitter/X post, n = 89) or to the control group (no promotion, n = 88). The primary outcome (citation counts) and secondary outcomes (website visits and altmetrics) were reassessed 4.5 years post-promotion. Between-group comparisons were performed using Welch's t-tests. A sensitivity analysis was conducted using negative binomial regression models, better approximating the non-linear distribution of citation counts. At 4.5 years, there was no significant difference between intervention and control groups for citation counts (12.76 ± 12.18 vs. 16.47 ± 21.92, p = 0.168) and website visits (1448 ± 1489 vs. 1503 ± 1692, p = 0.818). Altmetric scores were significantly higher in the intervention group (5.15 ± 3.88 vs. 1.74 ± 3.68, p < 0.001). The sensitivity analysis confirmed these findings, showing no significant difference in citation counts (IRR 0.78; 95% CI: 0.57-1.05; p = 0.101) but a significant increase in Altmetric scores (IRR 2.96; 95% CI: 2.09-4.19; p < 0.001). A longer observation time did not result in a significant difference in citation counts or website visits. Promoted articles were consistently associated with increased Altmetric scores. A low-intensity social media promotion may broaden visibility but does not influence long-term citations. More intensive promotion strategies have demonstrated short-term gains, but their ability to produce sustained long-term impact remains uncertain and warrants further investigation.