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. 2009 Jun 23;117(10):1571–1579. doi: 10.1289/ehp.0900561

Table 2.

Detailed list of add-on variables (Am and Fn), unstandardized variable coefficients (βm and γn), standardized variable coefficient (β), t-statistic and its significance (Sig) and partial correlations of the variables entered in the development of model 6, as defined in Equation 6.

Model Variables Unstandardized coefficients
m, γn)
Standardized coefficient
t-Statistic Sig Correlations
Percent cases report add-on Reference supporting variable
βm or γn SE β Zero order Partial Semipartial
Benzene
(R2 = 0.469)
(Constant) 0.609 0.196 3.108 0.002
Benzene modeled 0.140 0.082 0.096 1.696 0.091 0.316 0.093 0.068 100

Dichotomous variables Am
Volunteer has paints stored in the garage 1.905 0.210 0.405 9.082 0.000 0.464 0.447 0.364 7
Car kept in the garage 1.049 0.215 0.219 4.889 0.000 0.382 0.260 0.196 7 Batterman et al. 2006
Urban location 0.380 0.133 0.140 2.854 0.005 −0.094 0.155 0.114 38 Edwards et al. 2005
Volunteer visited hospital 1.320 0.316 0.170 4.171 0.000 0.183 0.223 0.167 3
Commute by electric or diesel train 0.350 0.179 0.083 1.962 0.051 0.023 0.107 0.079 10 Edwards et al. 2005
Gas main heating 0.455 0.123 0.172 3.714 0.000 0.032 0.200 0.149 3
Additional heating sources 2.087 0.668 0.148 3.122 0.002 0.175 0.169 0.125 60

Time variables Fn
Time exposed to constant or frequent ETS 0.003 0.001 0.279 5.994 0.000 0.285 0.313 0.240 15 Heavner et al. 1995
Time commuting in a car 0.005 0.001 0.153 3.597 0.000 0.243 0.194 0.144 11

Ethylbenzene
(R2 = 0.813)
(Constant) 0.981 0.198 4.944 0.000
Ethylbenzene modeled 0.156 0.156 0.032 0.995 0.320 0.117 0.055 0.024 100

Dichotomous variables Am
Volunteer has paints stored in the garage 1.668 0.309 0.142 5.393 0.000 0.183 0.284 0.128 7 Ilgen et al. 2001
Car kept in the garage 1.807 0.321 0.152 5.637 0.000 0.159 0.296 0.134 7 Song et al. 2007
Volunteer visited hospital 2.113 0.463 0.109 4.559 0.000 0.088 0.243 0.108 3 Song et al. 2007
Carpet has been fumigated 19.158 0.836 0.546 22.929 0.000 0.525 0.783 0.545 1 Yang et al. 2002
New carpet 0.202 0.200 0.025 1.006 0.315 −0.015 0.055 0.024 1
Volunteer works in a factory 3.881 0.836 0.111 4.645 0.000 0.085 0.247 0.110 3 Song et al. 2007
Additional heating sources 3.113 1.057 0.089 2.945 0.003 0.082 0.160 0.070 1 Song et al. 2007

Time variables Fn
Time painting or in presence of painters 0.074 0.003 0.675 28.345 0.000 0.662 0.841 0.674 3 Ilgen et al. 2001, Song et al. 2007

Styrene
(R2 = 0.868)
(Constant) 0.209 0.171 1.224 0.222
Styrene modeled 0.796 0.248 0.064 3.208 0.001 0.035 0.172 0.064 100

Dichotomous variables Am
Wood burning in fireplace 2.503 0.489 0.102 5.117 0.000 0.094 0.268 0.102 2 Austin et al. 2001
Carpet has been fumigated 31.987 0.688 0.926 46.475 0.000 0.922 0.930 0.925 1 Zuraimi et al. 2006

3-Ethenylpyridine
(R2 = 0.750)
(Constant) 0.109 0.022 4.912 0.000
3-Ethenylpyridine modeled −0.337 0.052 −0.318 −6.472 0.000 0.370 −0.333 −0.172 100

Dichotomous variables Am
ETS 0.178 0.051 0.116 3.482 0.001 0.468 0.187 0.092 30 Heavner et al. 1995

Time variables Fn
Time in presence of ETS 0.001 0.000 0.227 3.970 0.000 0.761 0.212 0.105 30 Heavner et al. 1995
Time exposed to constant ETS 0.003 0.000 0.215 5.204 0.000 0.711 0.273 0.138 6 Heavner et al. 1995
Time exposed to constant or frequent ETS 0.004 0.000 0.647 9.808 0.000 0.777 0.472 0.260 15 Heavner et al. 1995

Naphthalene
(R2 = 0.418)
(Constant) 0.381 0.082 4.659 0.000

Dichotomous variables Am
Incense burning 0.994 0.248 0.168 4.006 0.000 0.146 0.214 0.167 2
Photocopier, fax, or printer in the house 0.306 0.135 0.097 2.272 0.024 0.205 0.123 0.095 18 Zuraimi et al. 2006
Gas main heating 0.273 0.102 0.115 2.671 0.008 0.045 0.145 0.111 59
Packing or unpacking clothes 1.188 0.906 0.055 1.311 0.191 0.040 0.072 0.055 1 Edwards et al. 2005

Time variables Fn
Inverse time carpet was replaced in kitchen 0.921 0.693 0.058 1.329 0.185 0.068 0.073 0.055 7
Inverse time carpet was replaced in living room 0.164 0.333 0.021 0.493 0.622 0.001 0.027 0.021 7
Inverse time packing or unpacking clothes 20.078 1.435 0.600 13.991 0.000 0.603 0.608 0.584 1 Edwards et al. 2005

1,3-Butadiene
(R2 = 0.487)
(Constant) 0.115 0.036 3.232 0.001

Dichotomous variables Am
Visited a gasoline station 0.178 0.106 0.068 1.678 0.094 0.107 0.092 0.066 4
Commute by bus 0.108 0.070 0.062 1.538 0.125 0.094 0.084 0.060 4 Curren et al. 2006
Solvent use 0.112 0.135 0.034 0.834 0.405 0.117 0.046 0.033 13
Garage connected to the kitchen 0.401 0.091 0.176 4.403 0.000 0.145 0.235 0.173 5
Additional gas heating appliances 0.666 0.112 0.238 5.969 0.000 0.198 0.312 0.234 13

Time variables Fn
Time in presence of ETS 0.001 0.000 0.149 1.969 0.050 0.389 0.108 0.077 12 Heavner et al. 1995
Time exposed to constant or frequent ETS 0.001 0.000 0.236 3.150 0.002 0.375 0.171 0.124 30 Heavner et al. 1995
Time traveling 0.001 0.000 0.059 1.458 0.146 0.042 0.080 0.057 15 Curren et al. 2006
Time wrapping Christmas presents and cards 0.015 0.001 0.431 10.685 0.000 0.448 0.506 0.419 1
Inverse time since antimold use 2.001 0.338 0.241 5.925 0.000 0.247 0.310 0.232 1

Concentrations are measured in micrograms per cubic meter (μg/m ), time variables are measured in minutes, and inverse of time variables in minutes .