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55 Table 8. Crossing performance summary at PHB, pretest and posttest. PHB Performance Measure Pre Post Difference p-value Dual Opportunities (PA_Dual) 55.5% 89.3% 33.8% <.0001 Single Opportunities (PA_Half) 15.0% 4.1% 10.9% 0.0001 None Opportunities (PA_No) 29.5% 6.6% 23.0% <.0001 Dual Utilization (PU_Dual) 91.6% 98.3% 6.7% 0.0062 Single Utilization (PU_Half) 8.8% 8.3% 0.5% 0.9468 None Utilization (PU_No) 0.0% 0.0% 0.0% Average Delay (s) 16.0 5.8 10.2 0.0007 Delay>Min (s) 3.2 1.4 1.8 0.0044 85th Percentile Delay (s) 29.5 7.7 21.8 0.0001 O&M Interventions 2.4% 0.0% 2.4% 0.0112 not be interpreted as the PHB resulting in zero risk to blind The participant feedback at the two-lane roundabout pres- pedestrians. It is very unlikely that any treatment would result ents a somewhat different picture than the feedback at the in zero risk to blind pedestrians or sighted pedestrians, as evi- single-lane roundabouts or the CTL. The average of the dent by pedestrian injuries and deaths at intersections across responses on the confidence question ("How would you rate the country. The 0% intervention rate therefore should only your confidence in your ability to cross here safely on a scale be interpreted as the fact that no interventions were observed of 15, with 1 being not at all and 5 very confident?") was 4.0 during the 16 crossing attempts by each of the 13 participants in the pretest, 4.83 at the PHB installation posttest, and 4.58 during the posttest. in the RCW crossing posttest. On the question, "Would you Overall, the installation of the PHB resulted in signifi- use these crossings if they were on the most direct route home cant improvements in crossing performance from a delay from work?" in the pretest, 15 participants said yes, and 1 said and safety perspective. In the interpretation of the delay times, "no, would find another way." In the posttest, with the PHB, it needs to be highlighted that the study design used in the PHB 12 said yes and no one said no, and with the RCW, 11 said yes study assumed that pedestrians arrived at the crossing after the and one said no. While the numbers were positive in the pretest minimum green time had elapsed. Effectively, this design min- and posttest conditions, the comments that were noted along imized the potential delay encountered by pedestrians. At a with the responses changed considerably. In posttest debrief- phase cycle length of 38 s, this assumption is valid for pedes- ing, comments at the PHB were generally more enthusiastic, trian volumes of less than 90 per hour (which would result in with additions like "definitely!" or "would go out of my way pedestrian headways of 40 s assuming uniform arrivals). For to use them." heavier pedestrian flows, this assumption does not hold because A couple of questions were added for the Golden debriefing additional pedestrians are increasingly likely to arrive just that provide a little more insight into the participants' think- after the "Walk" phase has elapsed and higher delays are antic- ing. Participants were asked if they considered the crossings ipated. However, as demonstrated in a simulation-based sen- more risky, less risky, or of about the same risk as an intersec- sitivity analysis of roundabout PHB installations (Schroeder tion with a signal and four lanes of traffic. Table 9 shows the et al. 2008), additional pedestrians will also be more likely frequency of responses and percentages in parentheses. to join existing signal calls. The pedestrian delay therefore In the pretest, 17% considered the two-lane roundabout plateaus with increasing pedestrian demands, where the less risky, and about 40% each thought it was the same or magnitude of this terminal delay is a function of the signal more risky than a signalized intersection. In the posttest, at the phasing. PHB, 54% considered it less risky and 31% about the same risk. Only one person thought it was more risky, compared to seven in the pretest. At the RCW, 23% considered it less risky, 62% Participant Feedback about the same risk, and again only one person (8%) more risky Following each the pretest and posttest two-lane round- than a signal. Presumably, this suggested greater confidence about studies, participants were asked a series of questions and comfort in participants' perception of the PHB relative to about their perception of the crossing and the level of com- the RCW. Both treatments showed perceived benefits over the fort in their crossing decisions. The blank survey forms are base two-lane roundabout case, as well as the (hypothetical) provided in Appendix G. signalized intersection.