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6 CHAPTER TWO SURVEY METHODS AND RESULTS The three principal information sources for this study were: is problematic because there is no single definition or criterion (1) the project survey of small carrier owners/managers, for "small carrier" and because there is no central respondent (2) in-depth interviews with a subset of survey respondents, list that could serve as a practical basis for probability-based and (3) the research literature review. This chapter describes sampling (TRB Committee on Truck and Bus Safety 2010). the survey approach, specific methods, and provides principal Therefore, a nonprobability-based convenience sample was results. The carrier owner/manager survey asked respondents used. It might also be characterized as a judgment sample, questions about safety problems they faced, what safety man- because the participating trade associations were judged by agement practices they used, and the effectiveness of these the project team as being excellent sources for small carrier practices. Survey results relating to specific topics are also input. revisited in chapter four (Evidence Review). The survey sample space (i.e., potential respondents con- A general caveat regarding most of the survey responses tacted) consisted primarily of members of the participating is that they represent subjective responses to subjective ques- trade associations. In comparison to the conceptual popu- tions. A few questions were objective (e.g., questions asking lation, this sample space is itself biased toward organiza- safety managers whether or not they use a particular safety tions and individuals with more experience, past success, and management practice), but most called for subjective judg- safety conscientiousness than the overall conceptual popula- ments by respondents. Another caveat is that the respondent tion. Those returning the survey (whose responses are pre- sample should be regarded as a convenience and "judgment" sented here) were the respondents. Just as the sample space sample of interested, knowledgeable individuals, not as a rep- was likely a biased slice of the population, the respondent resentative sample of some larger population such as "all small sample was likely a biased slice of the sample space. In most carrier owners/managers." In spite of these caveats, survey surveys and almost certainly this one, those responding tended findings are revealing because of the comparative information to be more committed and interested in the topic than those they provide; for example, the perceived relative importance not responding. Moreover, they tended to be more edu- of various safety problems and perceived relative effectiveness cated and verbal than nonrespondents (Walonick 2010). Both of solutions. sources of bias almost certainly operated in the present survey. Critical to the success of the survey was the support of the A larger study focusing on the survey per se could likely following five CMV transport trade associations, two relating do a better job of capturing the conceptual population. Study to trucking and three to motorcoach transport. These organi- resources did not permit a rigorous, probability-based sam- zations solicited survey participation by their members through pling approach. The obtained sample, even if representing a e-mail requests containing links to the online survey. skewed sample of knowledgeable and safety-conscious small carrier respondents, still provided valuable information. It American Bus Association (ABA) accomplished the following objectives: Bus Industry Safety Council (BISC) National Association of Small Trucking Companies (NASTC) It tapped the views and practices of safety-active small OwnerOperators Independent Drivers Association carriers. (OOIDA) It provided information subjects' relative opinions on United Motorcoach Association (UMA). various safety problems and solutions. It provided contacts for follow-up interviews with carrier owners/managers regarding the practices of progressive SURVEY METHOD companies. Sampling Approach Questionnaire Design and Content The conceptual population for the survey was North American motor carrier (truck and bus) small carrier owners/managers. Appendix A presents the project survey form, reformatted for This population is amorphous and largely inaccessible to sur- inclusion in this report. The survey form consisted of the sec- vey research. Defining and reaching this conceptual population tions listed here (with question numbers in parentheses):

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7 Introduction, including brief statement of the study and dents. Researchers also prepared draft e-mail text for use by survey purpose, and a confidentiality assurance. the participating trade associations in soliciting their mem- (114) Safety problems faced. A series of 14 questions bers. The associations were asked to target carriers in the 3 to about the relative importance of specific safety prob- 75 power unit range, if possible; this range was considered lems facing small companies. These employed a 5-point inclusive of responding carriers who would meet the princi- Likert rating scale for importance. pal criterion (defined here) for inclusion in reported results. (1516) CSA (Compliance, Safety, Accountability) Separate files were used for each trade association so its compliance challenges. Two parts: member statistical results could be seen separately and pro- Selection of the two (out of seven) CSA Behavior vided to association officials for their use. In most cases, the Analysis and Safety Improvement Categories initial request e-mail was followed a few weeks later by a (BASICs) presenting the biggest safety challenges, second, follow-up request. and Selection of the two BASIC categories presenting Data Analysis and Interpretation the smallest safety challenges. (1730) Safety management practices. A series of 14 Survey tabulations for respondents from each trade associa- questions on (1) safety management practices they use, tion (and the fifth "general" file) were provided automatically. and (2) their perceived safety effectiveness using a These tabulations were entered onto an Excel spreadsheet 5-point Likert scale. These 14 practices should be con- and summed across the five sources. The following sections sidered as just a sample of possible small carrier safety describe specific aspects of data analysis and interpretation. practices. Many other worthy safety practices could not be included in the survey owing to survey length Principal Criterion for Inclusion of Data considerations. (3132) Important areas of safety management. Ten areas A specific criterion was applied to most survey questions to of safety management were listed; respondents limit the reported results to the principal focus of the study; Selected up to three (of the nine) they considered that is, those carriers large enough to have a "non-driver" most important; that is, having the greatest effect on manager but too small to have multiple managers. Because safety outcomes. most such managers retain their Commercial Drivers Licenses Selected up to three they considered least important; (CDLs) and may occasionally drive, a "nonnon-driver" man- that is, having the least effect on safety outcomes. ager was defined as one who drives less than 50% of the time. (33) Other comments regarding safety management in Question 34 of the survey was the basis for this filtering. small motor carriers. Open response box. Unless noted otherwise for a particular question, all reported (3435) Carrier size. Two multiple choice items: survey results in this report are for respondents who answered Owner/manager role in carriers of four "functional" "c" on this question: size ranges (see Appendix A, Question 34). Number of nonnondriver employees. (34) Which best describes you and your company? (3637) Information about respondent experience: (a) Solo owneroperator (i.e., you are the only driver). Years of experience as company owner/manager. (b) Driver (drives 50% or more of the time), but also oper- Total years of experience in commercial truck/bus ates other vehicles and employs other drivers. (c) Company owner/manager. Drives less than 50% of operations. the time. Performs most management and supervision (3839) Additional information about the company: tasks, including safety and compliance. Number of power units (open response box). (d) Owner/manager of company large enough to have mul- Principal operation type (eight choices). tiple managers, including a designated manager of safety and/or compliance. (40) A space to optionally provide an e-mail address to which to send the project report pdf. (41) A space to optionally volunteer for a paid inter- A total of 262 respondents (187 truck, 75 bus) completed view on innovative carrier practices for the project case the online survey, but only 112 of these (79 truck, 33 bus) studies. answered "c" on this question. The statistics reported and discussed elsewhere in this report are based on the responses of these 112 companies. Survey Distribution and Administration The survey was administered using TRB's online survey ser- Nonreporting of Response Percentages vice. The project team constructed the questionnaire, tran- scribing the questions provided in Appendix A to the auto- In accordance with CTBSSP policy, the survey results in this mated format. This included a web link to access the survey chapter and cited elsewhere in this report do not include and a link within the survey for accessing a copy (pdf) of the results percentages. Instead, raw numbers are cited (e.g., "42 questionnaire that could be saved and/or printed by respon- of 51 respondents . . ."). This practice reduces the likelihood