Road safety assessment is a formal procedure for safety potential and performance evaluation of existing roadways on the basis of historical crash data. Using risky driving behaviour as safety indicators measuring crash risk is one of effective approaches to deal with limitations of historical records. The objective of the study to estimate the relationship between sudden braking events and crash frequency as well as to investigate the associations between risky events and contributing factors leading to unsafe driving styles. The data cconsists of four datasets including sudden braking events, crash data, traffic information and geometric characteristics. A total of 36,000 sudden braking events and 76 crash records occurring on 163 road segments were obtained from All Thai Taxi Company Limited collected using Global Positioning System equipped with taxis in Bangkok. Besides, traffic information and geometric characteristics were extracted from the Traffic and Transport Department, and Policy and Planning Division, respectively which are maintained by the Bangkok Metropolitan Administration. The negative binomial regression was employed in the analysis. The result reveals that the number of intersections and the number of sudden braking events are statistically significant to increase the likelihood of crashes in Bangkok at the 5% confidence level. The number of intersections, traffic volume, the weekday, the evening-peak and night time have a significant effect on sudden braking occurrence at the 1% confidence level.