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Methods: A cross-sectional validation study was carried out on a total sample of 380 young adults aged 18 to 25 years who live in Tehran, Iran. Data were collected from January 27 to May 20, 2015, using a self-administered structured pool of 76 items that was developed from research on the theory of planned behavior. A panel of subject-matter experts evaluated the items for content validity index and content validity ratio, and the questionnaire was pretested. Exploratory factor analysis (EFA) was performed to test construct validity. The Cronbach's alpha coefficient and intraclass correlation coefficient (ICC) analyses were done to assess internal consistency and stability of the scale.
Results: From the initial 76 items, 38 items were found to be appropriate for assessing the pedestrian road crossing behavior (PEROB) of young adults in Tehran. A 9-factor solution revealed an exploratory factor analysis that jointly accounted for 63.8% of the variance observed. Additional analyses also indicated acceptable results for the internal consistency with Cronbach's alpha value ranging from 0.67 to 0.88 and ICC values ranging from 0.64 to 0.96.
Conclusions: This psychometric evaluation of a self-administered instrument resulted in a reliable and valid instrument to assess young adult pedestrians' self-reported road crossing attitudes and behaviors in Tehran. Further development of the instrument is needed to assess its applicability to other road users, particularly older pedestrians. 相似文献
Methods: This roadside observational study was conducted in 2015 and 2,178 personal cars with a child under 12 years aboard were observed on Tehran's streets in regard to use of child safety seats. Other variables such as the gender of the driver, driver's age group, type of street, region of municipality, time of day, and day of the week were also collected.
Results: Prevalence of child safety seat use was 4.3% and was significantly higher among women drivers, on freeways, and in municipal regions 1, 4, and 7.
Conclusions: The prevalence of child safety seat use in Tehran as a most populous member of the international safe community was very low and most children commuted in insecure situations in the vehicle. Therefore, it is proposed that plans should be made to increase the use of child safety seats in international safe communities. 相似文献
Methods: Simplicity, familiarity, concreteness, meaningfulness, and semantic closeness were the major assessment criteria, defining cognitive features by the earlier researchers in the field. A total number of 187 driving license applicants, with a mean age of 20.58 years (SD = 3.20), participated in the present survey. The participants rated cognitive features of the 6 dynamic symbols along a 0–100 scale.
Results: Significant main effect of the element factor type of the designed symbols on rating cognitive features revealed that the existence of car element was the best predictor for illustrating lane departure. The interaction of both element factor and location of element factor significantly affected the ratings. However, the location of element factor did not solely have any strong effect on the ratings. The results also demonstrated that semantic closeness received the highest overall mean score across symbols (M = 61.80), especially within the symbols that include the car element (M = 75.67). Moreover, a significant difference was observed between the average ratings of the cognitive features, despite the fact that a significant correlation was found between cognitive features.
Conclusion: The most considerable result of the current study was the match between the symbol with the highest ratings and the International Organization for Standardization (ISO)-related icon in appearance. Because previous studies demonstrated a strong correlation between comprehension scores of the symbol and both semantic closeness and meaningfulness, high-level comprehensibility of the best ranked symbol is expected. 相似文献