Table 3

 Potential predictors of early whiplash

Characteristic (number missing data)No early whiplash, n (%)Early whiplash, n (%)p Value
2; †Mann Whitney U; ‡Student’s t test.
BMI, body mass index.
Total number112 (22%)391 (78%)
Female67 (59.8%)265 (67.8%)0.117*
Age, median (IQ range)52 (39.2–69)40 (30–53)<0.005†
BMI, median (IQ range)25.8 (23.7–27.8)25.7 (23.2–29.6)0.650†
Previous neck pain4 (3.6%)85 (21.7%)<0.005*
Current smoker (7)19 (17.3%)82 (21.2%)0.362*
Married85 (75.9%)277 (70.8%)0.294*
Occupation (17)0.088*
    Unemployed or unskilled43 (40.2%)121 (31.9%)
    Semi-skilled or skilled42 (39.3%)204 (53.8%)
    Professional or managerial22 (20.6%)54 (14.2%)
Car size (4)0.033*
    Mini48 (44%)125 (32.1%)
    Small37 (33.9%)137 (35.1%)
    Large24 (22%)128 (32.8%)
Headrest present103 (92%)357 (91.3%)0.826*
Aware of impending collision26 (23.2%)95 (24.3%)0.813*
Head turned26 (23.2%)130 (33.2%)0.043*
Struck car driveable64 (57.1%)250 (63.9%)0.190*
Striking car driveable65 (58%)245 (62.7%)0.375*
Struck car stationary75 (67%)324 (82.9%)<0.005*
Speed difference (15), mean (SD)27.2 (12.7)29.1 (11.9)0.307‡