Cell Phone Activity and Trauma Patient Volume in New England Through the COVID-19 Pandemic: A Research Consortium of New England Centers for Trauma (ReCONECT) Study.

Background: We sought to understand whether cellular telephone activity in commercial spaces as a marker for population mobility would be associated with trauma admission volumes, taking advantage of cellular telephone data made available during the COVID-19 pandemic and large swings in population activity.

Study design: Trauma registry data from six level I trauma centers (TC) in New England were used to identify the number of daily trauma admissions (TA) from January 20th 2020 to July 31st 2021. The Device Exposure Index (DEX) is a standardized measure of daily cellular telephone interactions with other cellular telephones within a county. Spearman's rank correlation was calculated for the first wave of COVID-19 from March 2020 to May 2020 and for the entire study period. Center-specific Poisson models were created to control for seasonality.

Results: During the study period, daily mean TA was 42.8 (SD 10.7) and daily mean DEX was 60.6 (SD 26.8) overlapping device visits to venues per day. The daily DEX index was moderately correlated with TA from March to May of 2020 for five centers serving unique catchment areas, with Spearman's rho ranging from 0.22 to 0.47 (p<0.05). The sixth center where the catchment area overlaps with those of multiple level I centers had much lower correlation r = 0.06 (p=0.59). After controlling for seasonality, DEX vs. TA relationships remained significant among the six centers.

Conclusion: County-level daily DEX scores correlated significantly with TC-specific numbers of daily TA at 5 of 6 TC during the first three months of the study period. Additional research is needed; however, use of cellular telephone activity and interactions may be a valuable adjunct for trauma system planning.