[The effects of the parents' social class on infant and child death among 1995-2004 birth cohort in Korea].

OBJECTIVES: To investigate the effect of parents' social class on infant and child mortality rates among the birth cohort, for the period of transition to and from the Koran economic crisis 1995-2004. METHODS: All births reported to between 1995 and 2004 (n=5,711,337) were analyzed using a Cox regression model, to study the role of the social determinants of parents in infant and child mortality. The results were adjusted for the parents' age, education and occupation, together with mother's obstetrical history. RESULTS: The crude death rate among those under 10 was 3.71 per 1000 births (21,217 deaths among 5,711,337 births) between 1995 and 2004. The birth cohorts from lower educated parents less than elementary school showed higher mortality rates compared with those from higher educated parents over university level (HR:3.0 (95% CI:2.8-3.7) for father and HR:3.4 (95% CI:3.3-4.5) for mother). The mother's education level showed a stronger relationship with mortality among the birth cohort than that of the fathers'. The gaps in infant mortality rates by parents' social class, and educational level became wider from 1995 to 2004. In particular, the breadth of the existing gap between higher and lower parents' social class groups has dramatically widened since the economic crisis of 1998. DISCUSSIONS: This study shows that social differences exist in infant and child mortality rates. Also, the gap for the infant mortality due to social class has become wider since the economic crisis of 1998.

Healthy Twin: a twin-family study of Korea--protocols and current status.

"Healthy Twin" is a twin family study extension of the existing Korean Twin-Family Register. Healthy Twin recruits adult like-sex twins over the age of 30 and their adult family members. Healthy Twin protocols are primarily tailored to the study of the quantitative trait loci of complex traits as well as to the role of environment in the etiology of complex diseases. A full-length survey is underway, including questionnaires, health examinations and the collection of biological specimens. So far, 820 individuals (169 twin pairs and their families) have participated in the survey and 1068 individual twins (608 twin pairs) have replied to the mailed zygosity questionnaire as of July 2006. The first phase (2005-2006) of Healthy Twin will recruit 1550 individuals (including about 380 twin pairs), and the second phase a proposed 1500 to 2500 additional participants. We report study protocols and zygosity and the distribution of family size of the study participants.

The distribution of signs and pedestrians' walking behaviors in underground space--a case study of the underground shopping center in Taegon, Korea.

The objective of this research was to investigate how the pedestrians use the information in underground space. Furthermore, it is to determine the conditions under which pedestrians utilized signs. Therefore, the pedestrian walking behavior was investigated in an underground shopping center in Taegon City, South Korea. First, the routes taken by the pedestrians was observed; and secondly, the signs observed were categorized as follows, pedestrian movement patterns, conditions under which signs were utilized, the location of signs, the relationship between different spaces, the heights of the signs, and the types of information communicated by the signs. From our analysis of pedestrian walking behavior at the Taegon underground shopping center, it was found that it is necessary to adjust the content and placement of information signs for pedestrian use, because the content of the guidance information and the use of this information vary from place to place. As shown by our subjects' walking behavior, a good connection between information signs is necessary to provide good directional information to pedestrians.