Aggressive behavior of drivers: A new questionnaire defining the difference between hostile and instrumental behavior while driving

As part of an investigation of commuting stress, a new tool was developed for differentiating between two types of aggressive behavior in drivers: instrumental and hostile. The questionnaires evaluate aggressive behavior by measuring the level of aggression of each behavior and categorizing the behavior as instrumental or hostile. Two studies were conducted. In the first one, participants (N=104) received a questionnaire in which items culled from each aggression domain were tested along with attributes such as gender, age, driving experience; and previous involvement in a driving incident (a road accident or traffic ticket). Analysis showed that the questionnaire’s internal consistency was high for each aggression type and age comparisons for the two measures were found to be significant. In the second study, analysis of the data (N=326) enabled us to refine the operational definition of aggressive driving and to sharpen the distinction between the two types of aggression. Theoretical and practical perspectives of the instrument were discussed.