Table 3

Results of the secondary linear regression assessing the association between country-level determinants and the daily increase in deaths, including only countries reporting total COVID-19 tests performed up to 8 June 2020

Country-level determinantUnivariableMultivariable
Coefficient (95% CI)P valueCoefficient (95% CI)P value
Natural logarithm of population (10 million increase) (2018) 0.419 (0.038 to 0.800) 0.040 0.385 (−0.044 to 0.813)0.075
% population aged 65 years and older0.035 (−0.047 to 0.118)0.407
Pollution levels−0.003 (−0.037 to 0.030)0.848
Mean temperature (January–May) (2010–2016)−0.032 (−0.081 to 0.017)0.2070.026 (−0.052 to 0.104)0.484
International arrivals (1 million increase) (2018) 0.059 (0.039 to 0.079) <0.001 0.036 (0.008 to 0.063) 0.013
Population density0.002 (−0.002 to 0.007)0.2700.000 (−0.004 to 0.003)0.822
Diabetes prevalence (% of population ages 20–79 years) (2019)0.012 (−0.173 to 0.196)0.903
Prevalence – neoplasms – sex: both – age: Age-standardised (%) (2017) 0.582 (0.177 to 0.987) 0.009 −0.391 (−1.014 to 0.233)0.203
Median BMI0.107 (−0.205 to 0.419)0.507
Prevalent hypertension (%) (2015)0.140 (−0.240 to −0.039) 0.011 0.129 (−0.246 to −0.012) 0.032
Smoking prevalence, 2016 total (ages 15+ years)−0.016 (−0.077 to 0.045)0.610
Hospital beds (per 10 000 population)−0.009 (−0.027 to 0.009)0.323
WHO health index (2000)1.247 (−2.180 to 4.675)0.482
Population living in urban areas (%)0.007 (−0.030 to 0.044)0.710
GDP per capita, PPP ($1000 increase) (2018)0.242 (−0.016 to 0.499)0.077−0.045 (−0.325 to 0.235)0.739
Country-level average daily ambient ultraviolet radiation level – 2004−0.000 (−0.001 to 0.000)0.2830.000 (−0.001 to 0.000)0.310
Mean % of BCG vaccination coverage among 1-year-old children (1980–2019)0.028 (−0.039 to -0.017) <0.001 −0.011 (−0.029 to 0.007)0.221
Mean daily stringency index−0.033 (−0.074 to 0.008)0.1280.013 (−0.021 to 0.048)0.425
Total COVID-19 tests per 1000 population (up to 8 June 2020) 0.024 (0.008 to 0.039) 0.007 0.018 (0.001 to 0.034) 0.039
  • R2 for multivariable linear regression=0.8373.

  • The determinants achieving a 30% statistical significance level in univariable analyses (p<0.3) were included in the multivariable model.

  • Statistically significant results (P <0.05) are displayed in bold.

  • BMI, body mass index; GDP, gross domestic product; PPP, purchasing power parity.