Digital footprints of the US e-cigarette market: correlations among retail sales data, social media activity and Google search trends.

Introduction: The global market for electronic cigarettes (e-cigarettes) has been changing rapidly. There is limited research on whether real-time social media activities and Google search trends could reflect the e-cigarette market.

Methods: Using retrospective US retail sales data (Circana) of four popular e-cigarette brands (JUUL, Puff Bar, Hyde and Elf Bar) every 4 weeks from May 2021 to January 2023, we examined their Spearman correlations with the Google search trends and social media (Twitter, Reddit and Instagram) mentions during the same period. We applied linear mixed-effects models to the pooled brands data to further examine the association between sales and online activities, accounting for both within-brand temporal correlation and between-brand variability in baseline sales.

Results: We observed strong positive correlations between retail sales and Google search trends across all four brands, with Spearman correlation r ranging from 0.59 to 0.99 (p<0.001). Reddit mentions were also highly correlated with sales of each e-cigarette brand, with correlations ranging from 0.54 to 0.88 (p<0.01). Twitter mentions showed moderate to high correlations with sales, ranging from 0.46 to 0.88 (p<0.05). Instagram mentions demonstrated strong correlations with sales, ranging from 0.74 to 0.96 (p<0.001), except for Puff Bar (r=-0.06, p=0.793). The linear mixed-effects models indicated that Google Trends (estimate=0.391, p=0.002) and Twitter mentions (estimate=0.096, p=0.011) were significant predictors of sales.

Conclusions: Google search trends and social media activities can serve as digital footprints of the e-cigarette market, providing reliable data sources for near-real-time monitoring of the prominence of e-cigarette brands in the marketplace.