Journal of Advanced Transportation

Research Article

Determinants of Bicyclist Injury Severity Resulting from Crashes at Roundabouts, Crossroads, and T-Junctions

Table 4

Estimation results of the PPO model.


Variables	Roundabouts		Crossroads		T-junctions
Variables	Fatal	Serious	Fatal	Serious	Fatal	Serious

Bicyclist characteristics
Male	0.111 (0.052)	0.111 (0.052)	−0.16 (0.064)	−0.16 (0.064)	−0.089 (0.033)	−0.089 (0.033)
Age 1	0.706 (0.143)	0.706 (0.143)	0.309 (0.111)	0.309 (0.110)	0.275 (0.053)	0.275 (0.053)
Age 2	0.654 (0.071)	0.654 (0.071)		0.396 (0.085)	0.373 (0.043)	0.373 (0.043)
Age 3	0.467 (0.062)	0.467 (0.062)	0.405 (0.080)	0.405 (0.080)	0.325 (0.041)	0.325 (0.041)
Age 4	0.336 (0.060)	0.336 (0.060)	0.194 (0.082)	0.194 (0.082)	0.156 (0.041)	0.156 (0.041)
Age 6	−0.263 (0.066)	−0.263 (0.066)	−1.571 (0.354)	−0.298 (0.097)	−1.426 (0.178)	−0.282 (0.048)
Villager					−0.716 (0.235)	−0.114 (0.057)
Part-of-work	0.188 (0.075)	0.188 (0.075)			0.146 (0.052)	0.146 (0.052)
To-from-Work					0.981 (0.366)
Pupil-school					0.366 (0.098)	0.366 (0.098)

Intersection characteristics
Speed-limit	0.284 (0.054)	0.284 (0.054)	1.327 (0.340)	0.537 (0.097)	1.287 (0.188)	0.443 (0.047)
Junction-control	1.492 (0.424)		0.843 (0.318)		0.711 (0.232)
Divider	−1.095 (0.397)				−0.296 (0.076)	−0.296 (0.076)
Urban-junction	0.115 (0.055)	0.115 (0.055)	0.255 (0.110)	0.255 (0.110)	0.329 (0.041)	0.329 (0.041)
Road-wet	-4.438 (1.873)	-4.438 (1.873)

Environmental condition
Weather-fine			0.313 (0.131)	0.313 (0.131)
Weather-raining	0.193 (0.067)	0.193 (0.067)	0.308 (0.161)	0.308 (0.161)
Weather-foggy			−2.202 (1.064)
Night-peak					0.073 (0.032)	0.073 (0.032)
Night-light					−0.118 (0.033)	−0.118 (0.033)
Night-nonlight					−0.193 (0.074)	−0.193 (0.074)
February					−0.641 (0.263)
May			−0.192 (0.105)	−0.192 (0.105)
June	0.208 (0.108)	0.208 (0.108)
October			−0.179 (0.101)	−0.179 (0.101)

Bicyclist movement and location preceding the crash
Parked					−2.288 (1.003)	1.314 (0.600)
Waiting-go			0.869 (0.292)	0.869 (0.292)	0.801 (0.172)	0.801 (0.172)
Righting					−0.115 (0.050)	−0.115 (0.050)
Waiting-right			0.733 (0.388)	0.733 (0.388)	0.4 (0.122)	0.4 (0.122)
Over-nearside	−2.531 (0.759)		−2.294 (0.466)		−1.212 (0.393)
Ahead-right	−0.38 (0.120)	−0.38 (0.120)			−0.216 (0.072)	−0.216 (0.072)
Entering-main			−2.57 (1.063)		−1.179 (0.239)	−0.233 (0.055)
Lane-left	−0.441 (0.220)	−0.441 (0.220)	−1.034 (0.561)	−1.034 (0.561)
Busway					−1.389 (0.587)
Pavement	−0.495 (0.242)	−0.495 (0.242)			−1.285 (0.345)

Type of collision
Collision-point-front			−0.511 (0.116)	−0.511 (0.116)	−0.446 (0.055)	−0.446 (0.055)
Collision-point-back	0.407 (0.117)	0.407 (0.117)	0.812 (0.146)	0.812 (0.146)		0.656 (0.070)
Collision-point-right		0.324 (0.119)		0.575 (0.123)		0.457 (0.060)
Collision-point-left				0.414 (0.130)	0.576 (0.063)	0.576 (0.063)
Secondary-collision-on-road					−0.319 (0.066)	−0.319 (0.066)
Secondary-collision-off-road	−0.753 (0.253)	−0.753 (0.253)	−0.477 (0.281)	−0.477 (0.281)	−1.636 (0.386)	−0.69 (0.125)

Constant	4.576 (1.191)	1.042 (1.123)	4.787 (1.613)	−0.849 (1.460)	4.000 (0.301)	0.528 (0.087)
Number of observations	16418		11623		14491
Log-likelihood at zero, LL (0)	−7778.23		−5525.77		−6810.30
Log-likelihood at convergence, LL (β)	−6776.39		−4788.63		−5929.73
Pseudo R²	0.1288		0.1334		0.1293
AIC	15669.03		11166.97		13627.88
BIC	15869.39		11424.59		13800.70

Note. Standard errors are in parentheses. Level of significance: ∗ indicates parameter is significant at 0.05, ∗∗ indicates parameter is significant at 0.01, and ∗∗∗ indicates parameter is significant at 0.001.