Skip to main content

Table 2 Incidence rate ratios for COVID-19 derived from negative binomial regression showing both unadjusted and multivariable-adjusted analyses comparing days where wind speed < 8.85 KPH to days with ≥ 8.85 KPH wind speeds from March 16th–December 31st, 2020

From: A wind speed threshold for increased outdoor transmission of coronavirus: an ecological study

  Unadjusted Multivariable adjusted
Variable IRR [95% C.I.] aIRR [95% C.I.]
Wind speed < 8.85 KPH when temperature 16–28 °C 4.09 [3.16–5.28]
P < 0.001
1.45 [1.28–1.64]
P < 0.001
Wind speed < 8.85 KPH when temperature ≤ 15 or ≥ 29 °C 1.45 [1.04–2.03]
P = 0.029
1.03 [0.88–1.20]
P = 0.717
Maximal exterior temperature, °C   0.99 [0.99–1.00]
P = 0.021
Days since lockdown   0.94 [0.93–0.96]
P < 0.001
Days since reopening   1.07 [1.05–1.09]
P < 0.001
Holiday adjustment   1.12 [0.94–1.34]
P = 0.208
Snowfall, mm   0.93 [0.82–1.06]
P = 0.274
Rainfall, mm   1.02 [0.88–1.20]
P = 0.774
Eight-day forward/backward moving average   1.21 [1.19–1.24]
P < 0.001
α 1.02 [0.88–1.17] 0.16 [0.13–0.19]
  1. *KPH: kilometers per hour; °C: degrees Celsius; IRR: incidence rate ratio; 95% C.I.: 95% confidence interval. All models adjust for day of the week in which cases were reported and for the size of the county population adjusted for reductions due to individuals who had died or become immune due to COVID-19 during the period of observation. α is a measure of dispersion. P-values derived from Student’s T test