Among the vehicle to pedestrian collisions, 0.6％ of the casualties and 8.3％ of the fatalities involved pedestrians who were lying on the road. Therefore, developing a preventive measure for such type of collisions is required for reducing motor vehicle collision fatalities. The background of the collision involving pedestrians who were lying on the road was investigated using a database from the Institute for Traffic Accident Research and Data Analysis, Japan. Such collisions occurred more frequently in summer, and at weekends and night times, unlike other types of collisions. The 33.0％ of the victims lying on the road died, 30.8 ％ severely injured and 36.2％ mildly injured. Multivariate logistic regression analysis identified the following as major factors that positively influenced the fatalities: head or neck injuries; trunk injuries; trucks as offending vehicle; higher collision velocity; and hit-and-run cases. The following had a positive influence on severe injuries: trunk injuries; higher collision velocity; and hit-and-run cases. Decreasing the collision velocity, avoiding collisions to the head and neck or trunk, and preventing hit-and-run cases would be effective in reducing fatal or severe injuries to pedestrians lying on the road. Furthermore, it is important to identify pedestrians lying on the road for avoiding a collision. This could inform the development of safety systems for avoiding collisions with pedestrians lying on the road.

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Traffic accidents are caused by a variety of factors, including human error, road hazards, and vehicle defects. They are also enormously influenced by the social changes associated with population growth, urbanization, and motorization. Smeedʼs Law, proposed by R. J. Smeed in 1949, is an empirical rule relating traffic fatalities per vehicle （D/N） to per capita vehicle registrations （N/P）. According to Smeedʼs Law, increased motorization, as represented by per capita vehicle registrations, results in a decrease in the traffic fatality rate, which he defines as the ratio of traffic deaths to registered vehicles. Researchers have since conducted analyses using Smeedʼs Law to assess the traffic accident situation in various countries. In this study, statistical data were used to analyze the transition of traffic accidents in 34 countries in the International Road Traffic and Accident Database （IRTAD） in an effort to verify the ongoing applicability of Smeedʼs Law. It was found that Smeedʼs Law remains valid for accidents occurring over an extended period but that the transitions vary depending on a countryʼs economic development. Multiple regression analyses were conducted to examine the relationship between the accident fatality rate and various social context factors. Results of the analysis indicated that gross domestic product （GDP） per capita and the proportion of elderly in the population were the significant social factors, each having a p-value ＜0.005 and a negative coefficient. Evaluating the situation in countries with high GDP using the D/N measure in Smeedʼs Law was found to be particularly difficult since the traffic environment and automobile usage conditions can change substantially depending on the level of economic growth. Overall, it was judged to be all but impossible to conduct a meaningful uniform analysis of all countries simultaneously; rather, it is necessary to evaluate countries according to their individual conditions.

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In this paper, an Internet questionnaire survey of the general public was conducted regarding the effects of health condition detection and accident-avoidance technologies on the social acceptance of driving for patients with illnesses and the public consciousness to the traffic accident by the drivers with illnesses. The survey hypothesized that people would be more positive about the technologies if they or their acquaintances had experienced a change in physical condition while driving in the past. The subjects were 1,091 men and 409 women over 50 years old. The results suggested that even if devices that can detect sudden changes in physical condition and avoid accidents become widely available, driving by patients with illnesses that may cause sudden changes in physical condition may not be socially acceptable. On the other hand, the experience of changes in physical condition while driving by oneself or acquaintances raises the expectation of physical condition detection technology and positively influences the acceptance of driving by patients with illnesses. In addition, more than half of the general public thought the crime of the patient with illnesses will become serious if the patient who is allowed to drive on the condition that he or she wears a physical condition measuring device forgets to wear it. We believe that it is necessary to ensure safety by placing certain restrictions on vehicle start-up and/or automatically detecting changes in physical condition as soon as the driver starts driving. In conclusion, in parallel with the development of systems to support safe driving, the systems must be accepted by society. Therefore, it is necessary to consider measures to increase social acceptability for the systems.

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The aging rate continues to increase, and in 2065 it is predicted that the aging rate will reach 38.4%. It has been pointed out that the number of accidents caused by the elderly will increase in the future. Recently, accidents caused by elderly drivers from pedal operation error, when pedal change operation between brake and accelerator pedal have become a social problem. In this study, a sedan-type passenger vehicle with a pedal step of 20 mm was used as the test vehicle. The subjects were 5 elderly people （average age 72.8 years） and 5 young people （male average age 18.0 years）. And the subject was in a pedal-operated posture, putting the heel of right foot on the floor. The subjects were given the task of stepping on the brake pedal or accelerator pedal with their right foot. The author made a video of the movement of the foot when the subject changed from the accelerator pedal to the brake pedal, and analyzed the video. In elderly subjects, when subjects put heel in the position of the accelerator pedal and try to step on the brake pedal with right toe facing inward, a near miss, stepping on a place near the accelerator pedal, occurred. On the other hand, when the heel is placed between the accelerator and the brake, It was confirmed that no near miss occurred. Therefore, the author conducted an experiment on young subjects with the heel placement positions set to “Condition 1: Accelerator pedal position”, “Condition 2: Position between the accelerator pedal and the brake pedal”, and “Condition 3: Brake pedal position”. As a result, the following was confirmed. In “Condition 1”, subjects make a near miss like elderly persons, or step on the accelerator pedal. In “Condition 2”, there are both cases where near misses occur and cases where near misses do not occur. In “Condition 3”, near miss does not occur. “Pedal operation with heels on the floor” is a pedal operation method recommended for elderly drivers, such as stable operation because the heel is placed on the floor. However, when recommending this pedal operation method to elderly drivers, it is important to instruct including “putting the heel of the right foot in the position of the brake pedal”.

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In super-aging Japan, there have been sporadic incidents of vehicle collisions caused by elderly people. Although the National Police Agency recommends the use of a consultation desk with safe-driving counselors, the actual conditions and demographics of the consultations and counselors are little known at present. This study aimed to clarify the effective consultation skills of safe-driving counselors in the License Division of the National Police Agency in decision-making support for the voluntary surrender of older adult drivers’ licenses. We used a qualitative exploratory research method. Data were collected by a mail survey of safe-driving counselors in the License Division of the National Police Agency using an anonymous questionnaire, from May to August 2020. The data were analyzed using descriptive statistics or by a quantitative text analysis technique using KH Coder 3 software. We received valid responses from 132 counselors. The occupations of the counselors were: police officer （n＝71）, clerical staff （n＝34）, nurse （n＝28）, and others （including multiple answers）. Using morphological analysis, text data were extracted from a total of 447 sentences and 10,192 words from free-description answers. We conducted a frequency analysis for each term, calculated the Jaccard index, and performed a word co-occurrence network analysis, subgraph detection （random walks）, and Krippendorff content analysis. Keyword-in-context concordance was used to confirm the context and content of group-generated words, and each group was given a name that characterized its contents. This study was approved by the Tottori University Faculty of Medicine Ethics Committee. The most frequently extracted words were “parties” （i.e., persons concerned; 257 cases）, “voluntary surrender” （162 cases）, and “family” （155 cases）. In the word co-occurrence network analysis, the word with the highest mediation centrality was “parties.” Words with a strong co-occurrence relationship with “parties” were “family” （Jaccard index: 0.38）, “voluntary surrender” （0.27）, “will” （0.19）, “explanation” （0.2）, “understanding” （0.14）, and “conversation” （0.16）. We defined eight effective consultation skills: ［Respect the will of the parties］, ［Listen attentively and empathetically to the parties and their families］, ［Think from the standpoint of the parties］, ［Present objective data as judgment material］, ［Encourage voluntary surrender by demonstrating the benefits to people with mild cognitive impairment or dementia］, ［Show cases of traffic accidents among older adult drivers to help gain the parties’ understanding］, ［Facilitate agreement by understanding the anxiety of the parties］, and ［Coordinate and collaborate with the Regional Comprehensive Support Center］.

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