BackgroundThe alarming rate of child pedestrian fatalities highlights an urgent imperative for comprehensive test on children's street-crossing safety. Various methods in children's street-crossing studies were reviewed, and the advantages of the video-based experimental real-walk methods were introduced. AimThe present study aimed to develop a reliable assessment tool to evaluate children's crossing safety, assess its validity, and identify developmental characteristics of children's crossing abilities. MethodsWe recorded scenarios of vehicle-pedestrian interactions with varying distances and speeds at multiple suburban zebra crossings without traffic lights, and projected the videos to guide participants through a realistic crossing experience indoors. Sixty children, with 20 in each age group of 6, 8, and 11 years old (with equal numbers of boys and girls), were recruited. The children's crossing safety was measured using the dangerous crossing (DC), safe crossing rate (SCR) and time to contact (TTC), and they were also asked to complete the Chinese version of the Pedestrian Behavior Scale (CPBS). Their eye movements were also recorded with a portable eye tracker. ResultsThe correlation analysis of the simulated street-crossing video test revealed significant associations between behavioral indicators (DC, TTC), CPBS, and eye movement indicators, indicating strong empirical validity. Difficulty analysis confirmed the relatively high SCR among child pedestrians across all three age groups. Discriminant validity analysis demonstrated that age significantly predicted children's crossing safety, with 6-year-olds exhibiting lower safety in both behavioral and attentional dimensions compared to 8-year-olds and 11-year-olds. Finally, predictive validity results indicated varying effects of TTC on CPBS scores across different age groups, with a more significant predictive effect for younger children possessing lower street-crossing abilities. ConclusionThe video test effectively verified the critical period and developmental trend of children's crossing ability and demonstrated high validity. Overall, the developed video test is an effective tool for assessing school-aged children's crossing safety.