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9 graphic areas around Blacksburg, Virginia (location of Vir- safety and has extensive knowledge and experience relating ginia Tech and VTTI), Northern Virginia (location of the VTTI to the topic, although most did not and had not worked for principal investigator), and Iowa City, Iowa (location of the a motor carrier. More information on their backgrounds is University of Iowa). Letters to the large national sample and provided in Section 2.2.7. these geographic samples were addressed to "Fleet Safety All survey responses were confidential and there is no attri- Director" at the selected carriers. Other survey recipients were bution of responses by individual, company name, or other respondents from CTBSSP Synthesis 1 for whom contact infor- organizational affiliation in this synthesis. Statistics are cited mation was available. Most of these individuals were active in in the synthesis for the two major respondent groups: fleet industry trade association safety councils. Finally, to ensure an safety managers and other experts. adequate subsample of motor coach fleet safety managers, sur- vey forms were distributed directly to attendees at a Safety Counsel meeting of the American Bus Association. All survey 2.2 PRINCIPAL SURVEY RESULTS forms were accompanied by a cover letter and a stamped enve- lope addressed to research project personnel at VTTI in North- 2.2.1 Part 1: How Important Is the Problem? ern Virginia (primarily), VTTI in Blacksburg, or the University The first few questions of the survey were intended to of Iowa. Altogether, approximately 1,000 safety manager sur- assess respondents' views on the importance of the high-risk vey forms were distributed. Respondents in the three geo- driver phenomenon. These were the most conceptual survey graphic areas were also invited to a research project briefing, questions. Respondents were asked to attribute percentages held at each location after the study's completion. of crash risk to "behavior/skill" and to "uncontrollable fac- Even though most of the carrier safety manager survey tors (i.e., luck)." Implicit in this question is the idea that the distribution sample was randomly generated from a national concept of high-risk drivers assumes that there are significant directory, the safety manager respondent sample is perhaps behavior/skill differences among drivers. Both respondent considered as a convenience sample. Research project re- groups averaged around 70% (69% for safety managers and sources did not permit the design of a systematic subject sam- 72% for other experts) in their attribution of crash risk to pling and survey distribution process or the tracking of survey behavior/skill, although the safety manager attribution was return rates for various respondent groups. Moreover, those more variable. who complete and return a survey of this nature are likely to Respondents were asked a hypothetical question designed be those most interested in the topic and committed to sup- to elicit an assessment of the degree to which high-risk drivers porting efforts relating to it. Also, because there was a spe- are a problem for fleets (see Table 1). The majority of both cial effort to obtain passenger carrier fleet respondents, their respondent groups believed that the worst 10% of drivers were percentages in the respondent sample (13% long haul/motor associated with 50% or more of fleet crash risk. coach; 4% local/transit) were high compared with the overall Respondents were also asked to assess how consistent and commercial motor transport industry. enduring individual differences in crash risk are (see Table 2). The other expert survey form was distributed primarily to About two-thirds of both respondent groups believed that there professional associates of the principal investigator. Many had is a "strong tendency" for individual differences in crash risk been respondents to CTBSSP Synthesis 1. Many were individ- to be consistent and enduring year-to-year. uals active in TRB truck and bus safety activities, in particular the Committee on Truck and Bus Safety Research (ANB70). In addition to the mail distribution of approximately 125 2.2.2 Part 2: Driver Factors Associated with Risk surveys, about 30 were distributed directly during the 2004 TRB Annual Meeting, and a few were completed by FMCSA Respondents were asked to rate 16 personal factors with employees during a research project focus group held on the regard to their strength of association with crash risk. The topic. Obviously, this group is highly involved in motor carrier 5-point scale went from "0" (no association) to "4" (strong TABLE 1 Disproportion of risk SAFETY OTHER RESPONSE CHOICE MANAGERS EXPERTS Worst 10% 10% of problems 6% 0% Worst 10% 20% of problems 6% 6% Worst 10% 30% of problems 14% 19% Worst 10% 40% of problems 15% 21% Worst 10% 50+% of problems 59% 54%