Suda M, Nagamitsu S, Obara H, et al. - Given the effects of nightshift lifestyles on children as well as adults, and their association with sleep and behavioral problems among children, researchers sought to ascertain the correlations among sleep patterns, individual/environmental factors, and problematic behaviors in children at age 5 years. Using health‐checkup records, they obtained data concerning sleep patterns, individual / environmental factors, and problematic behaviors for 8,689 5‐year‐old children. Analysis revealed significant correlations among sleep patterns, individual / environmental factors, and problematic behaviors in 5‐year‐old children. Findings revealed significant adverse effects of late bedtime and short sleep duration on children's problematic behaviors. In addition, long television watching time, abnormality at birth, and lack of father's support had significant adverse effects on problematic behaviors, and significantly affected late bedtime and short sleep duration.