Suchergebnisse

Introduction The purpose of this study was to investigate the effect of cane tip design and cane technique modification on obstacle detection performance as they interact with the size, height, and position of obstacles. Methods A repeated-measures design with block randomization was used for the study. In experiment one, participants attempted to detect obstacles with either a marshmallow tip or a bundu basher tip. In experiment two, participants were asked to detect obstacles using either the constant-contact technique or a modified constant-contact technique. Results As predicted, the obstacle detection rate with the bundu basher tip (M = 66.1%, SD = 7.4%) was significantly higher than that with the marshmallow tip (M = 54.6%, SD = 6.8%), F(1, 11) = 24.19, p, r = .83. However, contrary to our hypothesis, the obstacle detection rate with the modified constant-contact technique (M = 56.0%, SD = 7.4%) was significantly lower than that with the constant-contact technique (M = 61.3%, SD = 5.2%), F(1, 13) = 6.49, p = .024, r = .58. In addition, participants detected the obstacles that were positioned at the center of their walking path (M = 61.9%, SD = 6.6%) at a significantly higher rate than those positioned slightly off to the side (M = 55.4%, SD = 7.3%), F(1, 13) = 10.73, p = .006, r = .67. Discussion A bundu basher tip was more advantageous than the marshmallow tip for detecting obstacles. Implications for practitioners Given the findings of the study, cane users and orientation and mobility (O&M) specialists should consider using or recommending a bundu basher tip (or a similar tip that has an increased contact area with the walking surface), particularly when the traveling environment often presents unexpected obstacles that may trip the cane user.

Introduction The study compared the level of satisfaction of 101 graduates with a distance education versus an on-campus program. Methods A self-administered anonymous survey was used to gather information about satisfaction from the recent graduates of a university personnel preparation program in visual impairments (response rate = 57.7%). The survey measured graduates' satisfaction with their programs in six subareas: (1) faculty-student interaction, (2) student-student interaction, (3) fairness of evaluations, (4) organization of courses, (5) adequacy of the difficulty of courses, and (6) practicum or internship experience. Results The program modality was not a significant predictor of overall satisfaction with a program once we controlled for the confounding variables, including age, program area, and presence of visual impairments (—.277 – .226, 95% CI). However, it was a significant independent predictor of faculty-student interaction (—.616 – —.012, 95% CI) and student-student interaction (—.875 – —.073, 95% CI). Discussion There was no significant difference in the two groups of graduates' overall satisfaction with the program, but although the findings are preliminary in nature, the graduates from the on-campus program indicated a higher level of faculty-student and student-student interactions. Implications for practitioners Given the findings of this study, prospective students who are interested in university personnel preparation programs in visual impairments may consider distance education programs an option that may satisfy them. Similarly, these programs may consider continuing their distance education programs as a satisfactory option for many students. However, the lower level of faculty-student and student-student interactions perceived by the distance education graduates may suggest a need to ensure a mechanism that facilitates such interactions more effectively.

This study examined the effects of cane tip type, cane tip size, cane shaft rigidity, cane handle material, and cane swing speed on the cane user's ability to discriminate surfaces of different roughness. A repeated-measures design with block randomization was used for each of the three studies. Blindfolded sighted and visually impaired participants attempted to identify which of the two grooved aluminum plates was rougher by swiping the plates using different cane tips, shafts, handles, and swing speeds. Participants correctly identified the rougher plate at a higher percentage with smaller cane tips (77.6% ± 8.7%) than with larger cane tips (72.1% ± 7.2%), p = .029, r = .54. Pencil tips (76.9% ± 8.4%) were more advantageous than ball tips (72.8% ± 6.5%), p = .028, r = .55. Slower cane swing speed (84.4% ± 2.6%) also allowed the participants to better discriminate the surfaces than faster swing speed (76.6% ± 6.0%), p = .002, r = .80. However, the cane shaft rigidity ( p = .499, r = .22) and cane handle material ( p = .694. w2 = 0.02) did not have a significant effect on the cane user's ability to discriminate the surfaces of different roughness. Given these findings, a cane user may want to use a smaller and/or cylindrical cane tip as opposed to larger and/or spherical cane tip for better surface texture change detection. In addition, a cane user may not want to swing the cane too wide or walk too fast since wider cane swing and faster walking speed tend to result in faster cane swing speed, which can compromise one's ability to detect sudden changes in walking surface texture. That being said, an Orientation and Mobility (O&M) specialist should assess each person's traveling environment when determining which cane tip and swing speed to use in a given situation.

This study examined the interaction effects of the amount of practice and the cane technique used in drop-off detection with a sample of 32 adults who were blind. The advantage of the constant contact technique over the two-point touch technique was significantly greater for the less experienced cane users than for the more experienced ones.

This study compared the drop-off detection performance with the two-point touch and constant contact cane techniques using a repeated-measures design with a convenience sample of 15 cane users with visual impairments. The constant contact technique was superior to the two-point touch technique in the drop-off detection rate and the 50% detection threshold. The findings may help an orientation and mobility instructor select an appropriate technique for a particular client or training situation.

Introduction Following the passage of the Pedestrian Safety Enhancement Act in the United States, the National Highway Traffic Safety Administration is setting a minimum sound level for hybrid and battery electric vehicles. With an aim to aid this effort, the present study investigated the timing and performance of critical street-crossing decisions by pedestrians who are visually impaired (that is, those who are blind or have low vision) at selected intersections. Methods Fourteen visually impaired adults with typical hearing along with a sighted experimenter made street-crossing decisions by indicating when they would initiate crossing using radio controller handsets. Participants' decisions were compared with the sighted experimenter's decisions to determine the level of their risk. Results At the residential intersection, the percentage of risky crossing decisions by participants was significantly lower when the decisions were made at lower ambient sound levels (M = 8.9%, SD = 6.9%) than when they were made at higher ambient sound levels (M = 35.3%, SD = 21.2%), p < .001. The participants were able to make significantly fewer risky crossing decisions during the windows of time when the ambient sound level was lower at the major-and-minor-street intersection as well ( p = .001). Discussion Participants were often able to take advantage of the troughs in ambient sound for making street-crossing decisions, and the decisions made in lower ambient sound level conditions were generally less risky than those made in higher ambient sound level conditions. Implications for practitioners Given the finding that the level of ambient sound detected when participants made crossing decisions was much lower than the average ambient sound level at a given intersection, as long as there are noticeable dips in ambient sound, average ambient sound level at a given intersection may not be the most relevant measure of background sound level when determining a minimum sound level for the hybrid and electric vehicles.

Objective: This study examined the effect of cane tips and cane techniques on drop-off detection with the long cane. Background: Blind pedestrians depend on a long cane to detect drop-offs. Missing a drop-off may result in falls or collision with moving vehicles in the street. Although cane tips appear to affect a cane user's ability to detect drop-offs, few experimental studies have examined such effect. Method: A repeated-measures design with block randomization was used for the study. Participants were 17 adults who were legally blind and had no other disabilities. Participants attempted to detect the drop-offs of varied depths using different cane tips and cane techniques. Results: Drop-off detection rates were similar between the marshmallow tip (77.0%) and the marshmallow roller tip (79.4%) when both tips were used with the constant contact technique, p = .294. However, participants detected drop-offs at a significantly higher percentage when they used the constant contact technique with the marshmallow roller tip (79.4%) than when they used the two-point touch technique with the marshmallow tip (63.2%), p < .001. Conclusion: The constant contact technique used with a marshmallow roller tip (perceived as a less advantageous tip) was more effective than the two-point touch technique used with a marshmallow tip (perceived as a more advantageous tip) in detecting drop-offs. Application: The findings of the study may help cane users and orientation and mobility specialists select appropriate cane techniques and cane tips in accordance with the cane user's characteristics and the nature of the travel environment.

Introduction: The modern long cane has been used by people who are blind for traveling for decades. This article describes parameters surrounding the collection of over 10,000 trials of people walking with the long cane to detect drop-offs or obstacles. Methods: The data include 10,069 trials representing 101 different participants in 366 conditions over 11 studies spanning the 9 years from 2007 to 2016. Each of the studies investigated different participant or cane characteristics or both in terms of their effect on either drop-off or obstacle detection. Results of detection performance in these studies appear in other articles. This article describes biomechanical measures derived from 3-D motion analysis equipment used during the studies. Results: Initial treatment of the large data set indicated that participants tended to not center their cane arc laterally on their body, deviating up to about 20 centimeters from midline. Arc widths averaged almost a meter, and arcs were generally centered. Participants were generally poor at being in step or having consistent rhythm. Coverage rates averaged about 85%. Discussion: Although participants might have demonstrated artificially high skill performance due to being in a research study, data do offer insights into mechanical performance of skills. This survey of the data set indicates that not centering the hand holding the cane does not decrease body coverage less than about 85%. However, further analyses will be conducted to delve more deeply into all aspects of the data. Implications for practitioners: Basic cane skills can be taught with short sessions and massed practice. Novices can acquire basic cane skills on par with cane users who are blind, but individual differences exist and the interplay of biomechanical variables needs to more fully understood.

Introduction Adults with vision loss often have difficulties reading prescription drug labels. An aspect of label readability that has not been well explored is the effect of container shape on the readability of the label. The research question addressed is: Does container shape affect the readability of prescription drug labels for persons with reduced visual acuity? Methods A repeated-measure, single-factor design with within-subject control was used with 23 adults with visual acuity of 20/60 or less. Individuals were recruited from southwest Michigan. Participants read 3 unique prescription drug labels on 4 differently shaped containers (flat, box, small cylinder, large cylinder) in block randomized order, for a total of 12 trials. The amount of time needed to locate and read aloud 6 pieces of label information and number of errors made in reading were measured, as well as each participant's preference in container shapes. Results A statistically significant difference was found between the mean number of seconds required to read flat container labels (flat and box shape, M = 54.62 seconds, SD = 23.8) and round containers (small and large cylinder shape, M = 64.46 seconds, SD = 36.3). No statistically significant effect of container type was found on the number of mistakes made in reading the label information, Wald χ2(3) = .71, p = 0.871. Seventy-eight percent of the participants chose the flat container as their preferred shape. Only 1 participant selected the box as his or her top choice. Discussion Containers with flat surfaces (flat and box) were easier to read, measured by speed, compared to containers with round surfaces (small and large cylinders). Although the study participants overwhelmingly preferred flat containers to the boxes, little difference was found between the two shapes in the amount of time that was needed to read labels affixed to them. Implications for practitioners Individuals with vision loss may need more time to read prescription drug labels affixed to the more typical cylindrical containers compared to flat ones.

This study examined the effect of adding an artificially generated alert sound to a quiet vehicle on its detectability and localizability with 15 visually impaired adults. When starting from a stationary position, the hybrid electric vehicle with an alert sound was significantly more quickly and reliably detected than either the identical vehicle without such added sound or the comparable internal combustion engine vehicle. However, no significant difference was found between the vehicles in respect to how accurately the participants could discriminate the path of a given vehicle (straight vs. right turn). These results suggest that adding an artificial sound to a hybrid electric vehicle may help reduce delay in street crossing initiation by a blind pedestrian, but the benefit of such alert sound may not be obvious in determining whether the vehicle in his near parallel lane proceeds straight through the intersection or turns right in front of him.