Skip to main content

Advertisement

Table 3 Summary statistics and Pearson correlation coefficients of 24-hour mean air pollutant concentrations and meteorological variables

From: Associations between air pollution and perceived stress: the Veterans Administration Normative Aging Study

  Summary statistics r
  n days Mean (SD) Median (IQR) PM2.5 BC PNC SO42- NO2 O3 Apparent temperature
PM2.5, μg/m3 4,680 11.0 (6.4) 9.3 (6.6, 13.7) 1.00 0.68 -0.10 0.83 0.49 0.22 0.32
BC, μg/m3 4,673 0.9 (0.6) 0.8 (0.5, 1.2)   1.00 0.07 0.49 0.66 -0.13 0.18
PNC, counts per cm3 2,580 23,615 (12,569) 20,613 (13,616, 31.548)    1.00 -0.22 0.46 -0.35 -0.67
SO42-, μg/m3 2,816 3.0 (2.4) 2.3 (1.5, 3.7)     1.00 0.24 0.39 0.41
NO2, ppm 4,747 0.02 (0.01) 0.02 (0.01, 0.03)      1.00 -0.23 -0.14
O3, ppm 4,740 0.02 (0.01) 0.02 (0.01, 0.03)       1.00 0.47
Apparent temperature, °C 4,734 10.1 (10.2) 8.7 (1.3, 18.9)        1.00
  1. Abbreviations:BC black carbon, IQR interquartile range, NO 2 nitrogen dioxide, O 3 ozone, PM 2.5 fine particulate matter ≤ 2.5 μm in aerodynamic diameter, PNC particle number counts, SD standard deviation, SO 4 2- sulfate.