Figures (0)  Tables (2)
    • Variable name Category 5-ft buffer 10-ft buffer 50-ft buffer
      Other crashes Scooter crashes Other crashes Scooter crashes Other crashes Scooter crashes
      Count Percent Count Percent Count Percent Count Percent Count Percent Count Percent
      Junction type 4-Leg intersection 196 67.8% 124 47.7% 372 81.8% 124 47.7% 2186 82.0% 124 47.7%
      T-Intersection 8 2.8% 45 17.3% 20 4.4% 45 17.3% 101 3.79% 45 17.3%
      Non-intersection 15 5.2% 40 15.4% 30 6.6% 40 15.4% 190 7.13% 40 15.4%
      Others 19 6.6% 51 19.6% 33 7.3% 51 19.6% 189 7.09% 51 19.6%
      Lighting condition Daylight 178 61.6% 198 76.2% 337 74.1% 198 76.2% 1943 72.88% 198 76.2%
      Dark-lighted 42 14.5% 36 13.8% 91 20.0% 36 13.8% 574 21.53% 36 13.8%
      Others 18 6.2% 26 10.0% 27 5.9% 26 10.0% 149 5.59% 26 10.0%
      Weather condition Clear 186 64.4% 226 86.9% 370 81.3% 226 86.9% 2079 77.98% 226 86.9%
      Cloudy 26 9.0% 18 6.9% 46 10.1% 18 6.9% 375 14.07% 18 6.9%
      Others 26 9.0% 16 6.2% 39 8.6% 16 6.2% 212 7.95% 16 6.2%
      Vehicle Maneuver Straight ahead 4 1.4% 117 45.0% 9 2.0% 117 45.0% 58 2.18% 117 45.0%
      Stopped vs straight ahead 21 7.3% 6 2.3% 30 6.6% 6 2.3% 227 8.51% 6 2.3%
      Both straight 56 19.4% 5 1.9% 106 23.3% 5 1.9% 582 21.83% 5 1.9%
      Straight vs turning left 69 23.9% 5 1.9% 131 28.8% 5 1.9% 824 30.91% 5 1.9%
      Right turn 23 8.0% 67 25.8% 54 11.9% 67 25.8% 292 10.95% 67 25.8%
      Other movements 65 22.5% 60 23.1% 125 27.5% 60 23.1% 683 25.62% 60 23.1%
      Driver age Older driver - No 187 64.7% 232 89.2% 361 79.3% 232 89.2% 2203 82.63% 232 89.2%
      Older driver - Yes 51 17.6% 28 10.8% 94 20.7% 28 10.8% 463 17.37% 28 10.8%
      Season of the Year Winter 52 18.0% 21 8.1% 108 23.7% 21 8.1% 669 25.09% 21 8.1%
      Spring 58 20.1% 47 18.1% 103 22.6% 47 18.1% 593 22.24% 47 18.1%
      Summer 46 15.9% 90 34.6% 100 22.0% 90 34.6% 585 21.94% 90 34.6%
      Fall 82 28.4% 102 39.2% 144 31.6% 102 39.2% 819 30.72% 102 39.2%
      Variable name Category 100-ft buffer 150-ft buffer 250-ft buffer
      Other crashes Scooter crashes Other crashes Scooter crashes Other crashes Scooter crashes
      Count Percent Count Percent Count Percent Count Percent Count Percent Count Percent
      Junction type 4-Leg intersection 3403 79.0% 124 47.7% 3849 74.5% 124 47.7% 4221 66.7% 124 47.7%
      T-Intersection 203 4.7% 45 17.3% 320 6.2% 45 17.3% 562 8.9% 45 17.3%
      Non-intersection 274 6.4% 40 15.4% 317 6.1% 40 15.4% 426 6.7% 40 15.4%
      Others 430 10.0% 51 19.6% 677 13.1% 51 19.6% 1119 17.7% 51 19.6%
      Lighting condition Daylight 3165 73.4% 198 76.2% 3775 73.1% 198 76.2% 4641 73.3% 198 76.2%
      Dark-lighted 908 21.1% 36 13.8% 1092 21.2% 36 13.8% 1307 20.7% 36 13.8%
      Others 237 5.5% 26 10.0% 296 5.7% 26 10.0% 380 6.0% 26 10.0%
      Weather condition Clear 3346 77.6% 226 86.9% 4001 77.5% 226 86.9% 4885 77.2% 226 86.9%
      Cloudy 627 14.5% 18 6.9% 730 14.1% 18 6.9% 902 14.3% 18 6.9%
      Others 337 7.8% 16 6.2% 432 8.4% 16 6.2% 541 8.5% 16 6.2%
      Vehicle Maneuver Straight ahead 129 3.0% 117 45.0% 175 3.4% 117 45.0% 245 3.9% 117 45.0%
      Stopped vs straight ahead 543 12.6% 6 2.3% 703 13.6% 6 2.3% 861 13.6% 6 2.3%
      Both straight 889 20.6% 5 1.9% 1029 19.9% 5 1.9% 1189 18.8% 5 1.9%
      Straight vs turning left 1049 24.3% 5 1.9% 1130 21.9% 5 1.9% 1301 20.6% 5 1.9%
      Right turn 456 10.6% 67 25.8% 511 9.9% 67 25.8% 612 9.7% 67 25.8%
      Other movements 1244 28.9% 60 23.1% 1615 31.3% 60 23.1% 2120 33.5% 60 23.1%
      Driver age Older driver - No 3604 83.6% 232 89.2% 4325 83.8% 232 89.2% 5313 84.0% 232 89.2%
      Older driver - Yes 706 16.4% 28 10.8% 838 16.2% 28 10.8% 1015 16.0% 28 10.8%
      Season of the Year Winter 1094 25.4% 21 8.1% 1332 25.8% 21 8.1% 1620 25.6% 21 8.1%
      Spring 920 21.3% 47 18.1% 1094 21.2% 47 18.1% 1353 21.4% 47 18.1%
      Summer 980 22.7% 90 34.6% 1168 22.6% 90 34.6% 1438 22.7% 90 34.6%
      Fall 1316 30.5% 102 39.2% 1569 30.4% 102 39.2% 1917 30.3% 102 39.2%

      Table 1. 

      Descriptive summary of the variables.

    • 5-ft buffer 10-ft buffer 50-ft buffer
      Estimate OR p-value Estimate OR p-value Estimate OR p-value
      Intercept 6.172 478.98 < 0.001 4.571 96.62 <0.001 2.774 16.02 0.002
      Junction type T-intersection 1.400 4.05 0.007 1.100 3.00 0.007 1.095 2.99 <0.001
      Non-intersection 1.176 3.24 0.020 0.956 2.60 0.020 0.845 2.33 0.003
      Others 2.450 11.59 < 0.001 1.940 6.96 < 0.001 1.756 5.79 <0.001
      Lighting condition Dark-lighted 1.460 4.31 0.001 0.624 1.87 0.070 −0.016 0.98 0.948
      Others 0.885 2.42 0.115 1.122 3.07 0.021 0.483 1.62 0.147
      Weather condition Cloudy 0.020 1.02 0.972 0.628 1.87 0.191 −0.089 0.92 0.782
      Others −0.933 0.39 0.089 −0.230 0.79 0.619 −0.147 0.86 0.685
      Vehicle maneuver Stopped vs straight ahead −6.223 0.002 < 0.001 −5.476 0.004 <0.001 −5.560 0.004 < 0.001
      Both straight −5.134 0.01 < 0.001 −5.034 0.01 <0.001 −4.829 0.01 < 0.001
      Straight vs turning left −6.080 0.002 < 0.001 −5.722 0.003 <0.001 −5.532 0.004 < 0.001
      Turning right 1.702 5.49 < 0.001 1.296 3.66 <0.001 0.947 2.58 < 0.001
      Other movements −3.262 0.04 < 0.001 −3.100 0.05 <0.001 −2.834 0.06 < 0.001
      Traffic volume Log (AADT) −1.123 0.33 0.001 −0.965 0.38 0.001 −0.895 0.41 < 0.001
      Driver age Older driver −1.020 0.36 0.012 −0.732 0.48 0.035 −0.510 0.60 0.064
      Season of the year Spring 0.519 1.68 0.357 0.712 2.04 0.114 0.619 1.86 0.070
      Summer 1.640 5.15 0.003 1.695 5.45 < 0.001 1.450 4.26 < 0.001
      Fall 1.051 2.86 0.041 1.390 4.01 0.001 1.291 3.64 < 0.001
      Number of observations 429 641 2777
      AIC 331 475 922
      Prediction accuracy 87.5% 84.3% 92.3%
      Sensitivity score 85.5% 91.7% 97.4%
      Specificity score 89.8% 67.8% 55.9%
      100-ft buffer 150-ft buffer 250-ft buffer
      Estimate OR p-value Estimate OR p-value Estimate OR p-value
      Intercept 1.859 6.42 0.017 1.959 7.09 0.009 2.124 8.36 0.004
      Junction type T-intersection 1.234 3.44 < 0.001 1.242 3.46 < 0.001 0.943 2.57 < 0.001
      Non-intersection 0.222 1.25 0.388 −0.086 0.92 0.729 −0.493 0.61 0.040
      Others 1.424 4.15 < 0.001 1.157 3.18 < 0.001 0.465 1.59 0.053
      Lighting condition Dark-lighted −0.050 0.95 0.826 −0.084 0.92 0.704 −0.159 0.85 0.466
      Others 0.336 1.40 0.265 0.225 1.25 0.444 0.125 1.13 0.662
      Weather condition Cloudy −0.248 0.78 0.420 −0.316 0.73 0.298 −0.386 0.68 0.195
      Others −0.381 0.68 0.270 −0.365 0.69 0.276 −0.416 0.66 0.203
      Vehicle maneuver Stopped vs straight ahead −5.593 0.004 < 0.001 −5.684 0.003 < 0.001 −5.639 0.004 < 0.001
      Both straight −4.508 0.01 < 0.001 −4.461 0.01 < 0.001 −4.418 0.01 < 0.001
      Straight vs turning left −5.057 0.01 < 0.001 −4.985 0.01 < 0.001 −4.884 0.01 < 0.001
      Turning right 0.961 2.61 < 0.001 1.039 2.83 < 0.001 1.031 2.80 < 0.001
      Other movements −2.548 0.08 < 0.001 −2.557 0.08 < 0.001 −2.533 0.08 < 0.001
      Traffic volume Log(AADT) −0.823 0.44 < 0.001 −0.895 0.41 < 0.001 −0.928 0.40 < 0.001
      Driver age Older driver −0.372 0.69 0.149 −0.321 0.73 0.206 −0.387 0.68 0.120
      Season of the year Spring 0.711 2.04 0.027 0.772 2.16 0.015 0.670 1.95 0.031
      Summer 1.309 3.70 < 0.001 1.396 4.04 < 0.001 1.301 3.67 < 0.001
      Fall 1.175 3.24 < 0.001 1.272 3.57 < 0.001 1.166 3.21 < 0.001
      Number of observations 4341 5109 6165
      AIC 1123 1188 1283
      Prediction accuracy 95.5% 96.0% 96.9%
      Sensitivity score 99.1% 99.4% 99.8%
      Specificity score 18.6% 11.9% 8.5%
      Bolded values are statistically significant at a 95% while bolded and italic are statistically significant at a 90% confidence interval.

      Table 2. 

      Logistic regression model results.