• Journal of Nutrition and Health
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• 제45권6호
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• pp.600-612
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• 2012

Nutritional researchers world-wide are using large-scale sample survey methods to study nutritional health epidemiology and services utilization in general, non-clinical populations. This article provides a review of important statistical methods and software that apply to descriptive and multivariate analysis of data collected in sample surveys, such as national health and nutrition examination survey. A comparative data analysis of the Korea National Health and Nutrition Examination Survey (KNHANES) was used to illustrate analytical procedures and design effects for survey estimates of population statistics, model parameters, and test statistics. This article focused on the following points, method of approach to analyze of the sample survey data, right software tools available to perform these analyses, and correct survey analysis methods important to interpretation of survey data. It addresses the question of approaches to analysis of complex sample survey data. The latest developments in software tools for analysis of complex sample survey data are covered, and empirical examples are presented that illustrate the impact of survey sample design effects on the parameter estimates, test statistics, and significance probabilities (p values) for univariate and multivariate analyses.

• Journal of Korean Academy of Oral Health
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• 제42권4호
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• pp.101-108
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• 2018

Objectives: The Korea National Health and Nutrition Examination Survey (KNHANES) is a national surveillance system that has been assessing the health and nutritional status of Koreans since 1998. Based on the National Health Promotion Act, the surveys have been conducted by the Korea Centers for Disease Control and Prevention (KCDC). Methods: An oral examination as part of The National Health and Nutrition Examination was proposed to calculate the sample design and survey participation. The surveying system was presented by classifying the measurement environment, screening, and survey items by year, and the merits and limitations of using the data were suggested by examining the status of survey quality management and the process of disclosing raw data. Results: This nationally representative cross-sectional survey samples approximately 10,000 individuals each year and collects information on oral examinations and oral health interviews. Data for the oral health component of KNHANES was obtained to assess the oral health status of Koreans and determine the prevalence of dental caries and periodontitis. The oral health data quality control of KNHANES was composed of three parts: "Education Program" and "Field Training Program" for quality control of oral health examiners (dentists) by the professional academy, and "Data management" by the KCDC. After completion of the three-step data check, the indicators of dental caries, periodontal disease, and oral health behavior were published in the National Health Statistics. Conclusions: To achieve the goals of oral health indicators, we will continue to monitor so that we can use it as basic data for oral policies and carry out various linkage analyses related to oral diseases.

• 대한지역사회영양학회지
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• 제24권1호
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• pp.1-17
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• 2019

Objectives: This study was performed to compare the dietary life of single- and non single-person households in the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: A nationally representative sample of 20,421 19-64-year-olds who had 24-hour recall data was taken from the 2014-2016 Korea National Health and Nutrition Examination Survey (KNHANES). Single- and non single-persons were compared for nutrient intake, dietary behaviors, food consumption patterns, nutrition education and confirm nutrition label. Results: The dietary intakes of dietary fiber and iron were lower in single-person households than in non single-person households. The lower the level of education and income, the lower the nutrient intake of single-person households. In the case of those aged 19 to 29, the breakfast skipping rate was higher in single-person households than in non single-person households. The higher the education level, the higher the breakfast skipping rate and the eating out frequency in the single-person households. In the food intake survey, the frequency of healthy food intake in single-person households was much lower than that of non single-person households. The confirmation rate of nutrition labeling was lower in single-person households than in non single-person households. Conclusions: This study shows that single-person households have poorer health-nutritional behaviors than multi-person households. Therefore, a nutrition education program based on the data of this study needs to be developed for health promotion of single-person households.

• 대한지역사회영양학회지
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• 제23권5호
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• pp.444-455
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• 2018

Objectives: The current survey environment is changing and participation rates in national nutrition surveys are decreasing. Therefore, the purpose of this study was to develop strategies for improving the nutrition survey system in the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: To develop an alternative system for conducting the KNHANES nutritional survey, we conducted focus group interviews with stakeholders of the survey, SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis, and expert reviews. In addition, spatial analysis of potential sites for conducting surveys instead of relying on household visits was performed, and the perception of nutritional surveys in the population eligible for KNHANES was evaluated. Results: Based on the results of the focus group interviews, SWOT analysis, and expert reviews, we propose two options for survey sites: vehicles specifically prepared for nutritional surveys and public facilities such as community service centers or public health centers. Among public facilities, community service centers were found to be more appropriate sites than public health centers because they were considered more accessible. About 90% of respondents would participate in the survey in public facilities and about 74% would in vehicles. Conclusions: Conducting national nutrition surveys in specially designed vehicles and public facilities could be a viable alternative to home visits. Next, the validity of these newly proposed nutrition survey methods needs to be compared to the results of the current national nutrition survey.

• Nutrition Research and Practice
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• 제14권6호
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• pp.679-690
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• 2020

BACKGROUND/OBJECTIVES: Concerns about regional disparities in heathy eating and nutritional status among South Korean adults are increasing. This study aims to identify the magnitude of regional disparities in diet and nutritional status among Korean adults who completed the 2017 Korea National Health and Nutrition Examination Survey (KNHANES). SUBJECTS/METHODS: The participants were a nationally representative sample of Korean adults aged 19 years and older from the 2017 KNHANES (n = 6,126). We employed the svy commands in STATA to accommodate the complex survey design. The relative concentration index (RCI), absolute concentration index (ACI) and index of disparity were used to measure regional nutritional inequalities. RESULTS: Overweight and obese adults were more prevalent among the poor than among the rich in urban areas (RCI = -0.041; P < 0.05), while overweight and obese adults were more prevalent among the rich than among the poor in rural areas of South Korea (RCI = 0.084; P < 0.05). Economic inequality in fruit and vegetable intake ≥ 500 g per day was greater in rural areas than in urban areas in both relative size (RCI = 0.228 vs. 0.091, difference in equality = 0.137; P < 0.05) and absolute size (ACI = 0.055 vs. 0.023, difference in equality = 0.032; P < 0.05). CONCLUSIONS: This study provides useful information identifying opposite directions in the relative concentration curves between urban and rural areas. Adult overweight/obesity was more prevalent among the poor in urban areas, while adult overweight/obesity was more prevalent among the rich in rural areas. Public health nutrition systems should be implemented to identify nutritional inequalities that should be targeted across regions in South Korea.

• 한국환경보건학회지
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• 제43권4호
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• pp.298-306
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• 2017

Objectives: Since 1998, the Korea National Health and Nutrition Examination Survey (KNHANES) has been conducted in order to investigate the health and nutritional status of Koreans. The food intake data of individuals in the KNHANES has also been utilized as source dataset for risk assessment of chemicals via food. To improve the reliability of intake estimation and prevent missing data for less-responded foods, the structure of integrated long-standing datasets is significant. However, it is difficult to merge multi-year survey datasets due to ineffective cleaning processes for handling extensive numbers of codes for each food item along with changes in dietary habits over time. Therefore, this study aims at 1) cleaning the process of abnormal data 2) generation of integrated long-standing raw data, and 3) contributing to the production of consistent dietary exposure factors. Methods: Codebooks, the guideline book, and raw intake data from KNHANES V and VI were used for analysis. The violation of the primary key constraint and the $1^{st}-3rd$ normal form in relational database theory were tested for the codebook and the structure of the raw data, respectively. Afterwards, the cleaning process was executed for the raw data by using these integrated codes. Results: Duplication of key records and abnormality in table structures were observed. However, after adjusting according to the suggested method above, the codes were corrected and integrated codes were newly created. Finally, we were able to clean the raw data provided by respondents to the KNHANES survey. Conclusion: The results of this study will contribute to the integration of the multi-year datasets and help improve the data production system by clarifying, testing, and verifying the primary key, integrity of the code, and primitive data structure according to the database normalization theory in the national health data.

• Nutrition Research and Practice
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• 제15권4호
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• pp.528-540
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• 2021

BACKGROUND/OBJECTIVES: In a healthy person, from 35 years of age, there is an annual loss of muscle mass at the rate of 1-2% and is associated with a decline in the quality of life. This study aimed to identify the particular dietary patterns associated with the risk of lower lean muscle mass in Korean postmenopausal women. SUBJECTS/METHODS: The Korea National Health and Nutrition Examination Survey (KNHANES) is a population-based, continuous cross-sectional annual survey. The participants of the KNHANES IV (2008-2009) and V (2010-2011) were considered for this study. The study sample consisted of 1548 postmenopausal women, aged 45-86 years. Lower lean muscle mass was defined as having appendicular skeletal muscle mass corrected for body weight less than 1 standard deviation of the young reference group aged 20 to 39 years in KNHANES IV and V. To identify the dietary pattern using factor analysis, 24-h recall data was used. RESULTS: The prevalence of lower lean muscle mass was 31.3% in this study population. Four dietary patterns were identified by factor analysis; 'Diverse', 'Western', 'Traditional', and 'Snacks and beverages'. The 'Western' pattern, highest factor loadings for flour and bread, potatoes, red meat, processed meat, eggs, and cheese, was significantly associated with a high (60%) risk of lower lean muscle mass (odds ratio [95% confidence interval] = 1.60 [1.07-2.39], P for trend = 0.01) after adjustments for potential covariates. The other 3 dietary patterns were not associated with lower lean muscle mass. CONCLUSIONS: The study findings suggest that the 'Western' dietary pattern that includes flour and bread, potatoes, red meat, processed meat, eggs, and cheese, may be associated with a higher risk of lower lean muscle mass in Korean postmenopausal women.

• 대한의생명과학회지
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• 제28권3호
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• pp.178-185
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• 2022

The purpose of this study was to analyze the effect of chewing difficulty on osteoarthritis in Korean adults. Data from the National Health and Nutrition Examination Survey for two years from 2019 to 2020. The collected data were analyzed using the SPSS (21.0) program using composite samples, and the mean crossover analysis and logistic return analysis were performed. An analysis of the effects of chewing difficulty on osteoarthritis in korean adults showed that those with chewing difficulty had a 2.02 fold higher risk of osteoarthritis (95%CI=1.56~2.42) and a statistically significant difference (P<0.05). The association between the chewing difficulty on osteoarthritis could be confirmed, and measures improve of the oral health and preventing osteoarthritis should be prepared.

• 보건교육건강증진학회지
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• 제31권2호
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• pp.1-14
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• 2014

Objectives: This study aimed to investigate factors influencing suicidal ideation among Korean adults. Methods: Cross-sectional data from the fifth Korea National Health and Nutritional Examination Survey conducted in 2012 were analyzed in this study. The subjects were categorized into three groups by subjects' age(defined as young adults(20-39), middle-aged adults(40-59), and the elderly(60 or more). Data were analyzed by frequency, Chi-square test and multiple logistic regression using SPSS 18.0. Results: The factors influencing suicidal ideation were different among three age groups. The influencing factors were (1) gender, marital status, household income, perceived stress and depression in the young adult group, (2) household income, perceived health status, perceived stress and depression in the middle-aged group, (3) gender, regular physical activity, smoking, perceived health status, perceived stress and depression in the elderly group. Conclusions: The health education considering the characteristics of each age group should be developed and applied to prevent adults' suicidal ideation because the factors influencing suicidal ideation were revealed differently between the age groups.

• Nutrition Research and Practice
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• 제8권1호
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• pp.81-93
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• 2014

This study was conducted to investigate nutrient consumption by Korean adults in various places. To accomplish this, we used the 1998-2009 Korea National Health and Nutrition Examination Survey (KNHANES). Subjects of this investigation were over 19 years and the study included 37,160 people. The meals were categorized as breakfast, lunch, dinner, and snacks consumed at home, or while eating-out. Investigation of the rate of consumption at serving places based on daily meals and years showed that eating-out generally increased with time. The consumption of meals prepared at home was higher than that of meals consumed anyplace else in 1998, 2001, 2005, and 2007-2009. However, the rate of consumption of home meals decreased from 1998 to 2007-2009, while the rate of eating-out increased during this period. Annual nutrient intake according to serving places with respect to meals, energy, fat, and sodium were significantly lower in home meals than those consumed elsewhere in 2007-2009 relative to 1998. The sodium intake and energy distribution ratio of fat in meals consumed while eating-out increased significantly from 1998 to 2007-2009. The energy, fat and sodium intake and energy contribution ratio of fat consumed in meals at institutions was significantly higher in 2007-2009 than in 1998. Based on these results, additional research is required to develop guidelines for dietary life improvement at each serving place and to address education and policies for balanced nutrition intake.