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13 CHAPTER 3 Survey of Agencies This chapter provides a summary of several surveys that were prioritized list of strategies, the research team felt that it was conducted of state and local agencies as part of this project. The necessary to contact select agencies by telephone to get further intent of this task was to obtain information on the installation information regarding their roadway, traffic, crash data, and of treatments by different agencies, determine their priorities for installation records. In order to be able to do this efficiently, different treatments, and assess the quality of the available data. it was necessary to develop a shorter list of treatments for further consideration. As discussed in Chapter 1, the research Web-Based Surveys team considered the likelihood and importance of evaluating each strategy based on the following: The web-based surveys were developed using a tool called Zoomerang. The intent of the web-based survey was to deter- Extent of the coverage in previous/ongoing work. Chapter 2 mine if a particular agency had installed a particular treatment, provides a summary of the CMFs developed in previous the approximate number of installations, and the agency's research. assessment of the importance of knowing the CMF of a par- Importance to the user (as identified in the survey response). ticular treatment. Based on the research team's past experience This is assumed to be a good measure of how often a in conducting surveys of this nature, the research team felt that treatment would be implemented if a sound CMF were the shorter the survey, more agencies will respond. Hence, to developed (i.e., high interest would imply higher future improve the response rate, the list of treatments was divided implementation). into two parts (Part 1 and Part 2) based on an assessment of Ability to identify crash effects. Strategies that may lead to how often specific treatments are installed in the field and the diversion of traffic and/or have a system-wide effect will quality of CMFs that are available from previous research. require more extensive data collection efforts and hence Part 1 requested information for 23 treatments and Part 2 may not be cost effective. Similarly, treatments that may requested information for 36 treatments. have a small effect on total crashes may require a significantly A draft version of the web-based survey was submitted to the NCHRP panel in March 2007. Changes were made to the sur- large sample of sites to conduct an evaluation and hence vey after receiving comments from the NCHRP panel. The may not be cost effective. Data assessment. This was done based on the responses to surveys were launched in June 2007. The surveys were posted online and an e-mail notification the web survey and the research team's knowledge based was sent to State DOTs, selected local agencies, and listservs on working with HSIS and the FHWA Low Cost Pooled including the Traffic Control Device listserv and the State Safety Fund Study. Engineer listserv. Individual requests were also sent to 130 local agencies. Forty-three agencies responded to Part 1 of the survey, The research team also attempted to examine a measure of and 33 agencies responded to Part 2 of the survey. "crash harm"--the size of the national crash problem poten- tially affected by each treatment. The first step in this analysis was to assign a primary crash type to each treatment that was Assessment of User Priorities being studied (e.g., left-turn crashes for left-turn phasing). and Development of Short List The next step was to use the General Estimate System (GES) The results of the survey were summarized and disseminated to calculate the number of crashes per year for each primary to the project team. In order to select a recommended and crash type that was identified earlier. By multiplying the