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Sang-Jin Chung

Publications and source records attributed to Sang-Jin Chung.

3 recordsLinked to original sources

Ready-to-eat breakfast cereal consumption enhances milk and calcium intake in the US population.

BACKGROUND: Inadequate intake of calcium-rich foods among US adults and children is a public health concern. Fluid milk is one of the best calcium sources because of its bioavailability and its versatility as both a beverage and a complement to various solid foods. One of the foods commonly consumed with milk is ready-to-eat breakfast cereal (RTEC). OBJECTIVE: We aimed to establish the association between the intake of RTEC, milk, and calcium within the context of the most current population dietary practices. We hypothesized that RTEC consumption facilitates milk consumption and is associated with adequacy of calcium intake in the US population. DESIGN: The most recent National Health and Nutrition Examination Survey, 1999-2000, data set was used as the source of data for this research. SUBJECTS/SETTING: US subjects aged 4 years and older (n=7,403), excluding pregnant and/or lactating women. Data were stratified according to sex and age (4 to 8 years, 9 to 13 years, 14 to 18 years, 19 to 30 years, 31 to 50 years, 51 to 70 years, and 71+ years), and then by consumption of breakfast, RTEC, and milk. STATISTICAL ANALYSES PERFORMED: SAS (release 8.1, 2000, SAS Institute Inc, Cary, NC) and SUDAAN (release 8.0.2, 2003, Research Triangle Institute, Research Triangle Park, NC) were used to calculate sample weighted means, standard errors, and population percentages. Multiple regression and multiple logistic regression models, with controls for covariates, were used to determine the predictability of total calcium intake from breakfast consumption compared to breakfast nonconsumption, and from inclusion of RTEC and milk in the breakfast meal compared with breakfast meal content without RTEC and milk. RESULTS: RTEC was predominantly consumed at breakfast. Average calcium intake at breakfast was seven times greater when RTEC was consumed with milk than when RTEC was consumed without milk. In multiple regression analyses, breakfast consumption, and milk consumption with or without RTEC all strongly predicted total daily calcium intake (P<0.05) while controlling for covariates. The percentage of respondents below the Adequate Intake level for calcium was higher for non-RTEC breakfast consumers than for RTEC breakfast consumers in all age-sex categories except those older than age 70 years, and girls aged 9 to 13 years. CONCLUSIONS: Consumption of RTEC at breakfast was associated with greater daily intake of both milk and calcium in all age and sex groups in the US population.

Adolescent↗

Exact tests for one sample correlated binary data.

In this paper we developed exact tests for one sample correlated binary data whose cluster sizes are at most two. Although significant progress has been made in the development and implementation of the exact tests for uncorrelated data, exact tests for correlated data are rare. Lack of a tractable likelihood function has made it difficult to develop exact tests for correlated binary data. However, when cluster sizes of binary data are at most two, only three parameters are needed to characterize the problem. One parameter is fixed under the null hypothesis, while the other two parameters can be removed by both conditional and unconditional approaches, respectively, to construct exact tests. We compared the exact and asymptotic p-values in several cases. The proposed method is applied to real-life data.

Anti-Bacterial Agents↗

Urban and rural differences in the prevalence of gender and age specific obesity and related health behaviors in Korea.

The objective of this study was to discuss the residential difference in gender and age specific prevalence of obesity by body mass index (BMI) and obesity related health behaviors in the Republic of Korea. A total of nationally representative 2,583 men and 3,087 women (age: 20-64 yr) was used as subjects from 1998 National Health and Nutrition Survey. All statistics were calculated using SUDAAN to consider a stratified multistage probability sampling design. The prevalence of obesity (BMI> or =25) was significantly different by age, gender and residential areas. Although younger men aged 20-49 yr did not show a residential difference in the prevalence of obesity, men aged 50-64 yr showed differences, highest in big cities and lowest in rural areas. However, in women, a higher prevalence was observed in rural areas compared to urban areas in the younger age group (20-49 yr), but not in the older age group. Residential differences of obesity related health behaviors existed mostly in the older population, but not in the younger population. The urban-rural differences demonstrate the various stages of behavioral transition that Korea is currently undergoing. Therefore, different strategies considering those factors are needed to manage obesity problems in Korea.

Adult↗