Given the complexity and the difficulty of controlling contributors effectively, road passenger transport often results in serious injuries and fatalities. The purpose of this study is to identify the main contributors to coach and bus accidents and to provide policy recommendations for making improvements in accident prevention. The Driving Reliability and Error Analysis Method 3.0 (DREAM 3.0) was modified and used to analyze the contributing factors (i.e. phenotypes and genotypes in DREAM) and their casual mechanisms. By having statistical analysis and social network analysis (SNA) adopted, the main genotypes and phenotypes of the DREAM charts were identified. The results of the study showed that A2.1 (too high speed) was the key phenotype and the main genotypic process chain leading to the phenotype was “inadequate safety management → inadequate training → inadequate skills/knowledge → misjudgment of the situation → too high speed” on all types of road. For A2.1 (too high speed), C2 (misjudgment of the situation) was the dominant genotype, while N5 (inadequate safety management) was the root cause of most genotypes. This suggests that road passenger transport companies, as the responsible parties, often fail to implement or violate safety prevention and control systems. Government regulators should promote the policy system and incentivize them to fulfil their safety management responsibilities. The government should also educate the public and improve the road environment to reduce passenger-related risks and the impact of environmental factors on drivers.

The purpose of this study was: (1) to propose a classification system for the contributory factors behind major coach and bus accidents with mass casualties based on the human factor analysis and classification system (HFACS); and (2) to identify the main contributory factors behind accidents and the main indicators of the causal factors. Based on 56 official investigation reports of major coach and bus accidents with more than 10 fatalities, a qualitative content analysis was conducted to develop a modified classification system for the contributory factors behind these accidents, and a gray correlation analysis was conducted to identify the main causative factors and indicators by calculating the correlation degrees. The results showed that the modified classification system for the contributory factors behind major coach and bus accidents can be divided into seven levels: government regulations, the organizational influence of passenger transportation enterprises, unsafe internal operational supervision, preconditions for drivers’ unsafe acts, drivers’ unsafe acts, proximate causes other than the driver’s act, and moderating factors affecting accident severity and probability. The organizational influence of passenger transportation enterprises is the most significant factor affecting the accidents. Thus, passenger transport enterprises must systematically strengthen their responsibility and safety management to prevent accidents. Accident investigations should begin with the accident process to determine the proximate cause as well as the factors that influence the likelihood and severity of the accident.