• 대한지역사회영양학회지
• /
• 제3권3호
• /
• pp.423-429
• /
• 1998

This study examined within- and between-person variation in nutrient intakes in order to estimate the degree of precision in dietary assessment among 37 males and 46females whose mean age was 70.4 years old. To collect dietary data, each subject was interviewed 5 or 6 times using a 24-hour recall method during a 3 month period. Within- person variation ranged from 23.5% to 101.2%. Lower values of within-person variation were observed in energy, carbohydrated, protein and phosphorous while higher value was observed in vitamin A. Between person variations of nutrient intakes ranged 12.6-23.5% in most nutrients. With 1 day dietary data, observed nutrient intakes were estimated to within 6-25% of the group's usual9true) intakes and 52-198% of the individuals' usual intakes. The values of these maximum percentage deviations became smaller when the number of dietary recalls increased. The results of this study suggest that the Korean elderly subjects appear to have a slightly less diverse diet compared to young Korean women. Within persons, intakes of nutrients largely from animal sources were more variable for the Korean elderly than for their counterparts in Western countries. This study also implies that commonly used 1 day dietary study may be appropriate for assessing group means of nutrient intakes, but clearly not appropriate for assessing individual's nutrient intakes.

• Journal of Nutrition and Health
• /
• 제29권9호
• /
• pp.1028-1034
• /
• 1996

This study examined within-and between-individual variation in nutrient intakes in order to estimate the degrees of precison in dietary assessment among 59 female volunteers aged 21-23 years. Self-recorded 7-day dietary recalls and records were collected by during a 3 month period. Between the recall and record methods, there were little difference of within-and between-individual variations. Within-to-between individual variation ratios were > 2.0 for most of the nutrients examined, and were higher for niacin, vitamin A and C (>2.5) in the recals and for calcium, iron, vitamin A and C(>3.0) in the records. With 7-day dietary data, observed nutrient intakes were estimated to within 26-107% of the subjects' true(usual) intakes, among those vitamin C and energy showed the highest and lowest values, respectively. Correlation coefficients between observed and true nutrient intakes were 0.73-0.81 for the recalls and 0.68-0.77 for the records. In order to estimate with 20% precision, 12-13 days of dietary study were required for energy, 46 for calcium, 71-72 for vitamin A, and 199-200 for vitamin C. Attenuation factor ranged 0.73-0.81 for the recalls and 0.68-0.77 for the records. This study implies that commonly used 1 or 3 day dietary studies may not be appropriate for assessing individuals' nutrient intakes. Further research focusing on the methodological issues in the assessment of Korean diet are needed for between understanding of the relationship between diet and health in Koreans.

• Journal of Nutrition and Health
• /
• 제37권10호
• /
• pp.917-927
• /
• 2004

This study was performed to examine component of variance in nutrient intakes and to estimate the level of accuracy with varying degree of precision in order to achieve estimates of usual nutrient intakes. Three-day dietary records including both weekdays and weekends were collected every 4 season over a I-year period from 36 males and 93 females aged 40 - 65 y. For each nutrient, we partitioned total intake variance into weekly (weekday vs weekend), seasonal, within- and between- individual variation as components of variance, using analysis of variance. It was found that major components of variance were within- and between-individual variation. Particularly, within-individual variation (57.2 - 87.1 %) was greater than between-individual variation (12.2 - 37.4%) for all nutrients. Weekly and seasonal variation contributed small components of variance for most nutrients. For protein, fat and carbohydrate, there were a little significant weekly variation (0.00 - 1.35%) in females but not in males. For some micronutrients, there were moderately significant seasonal variation (0.15 - 5.48%) in both sexes. Ratio of within- to between- individual variation ranged 1.4 (vitamin B$_2$) -4.5 (vitamin B$_1$) in males and 1.6 (carbohydrate) -2.9 (fat) in females. With total 12-day dietary records data, the maximum percentage deviation of observed intakes from usual (true) intakes ranged 12-37%. To estimate usual individual intakes within 20% of the true mean with 90% confidence level, 3 - 9 days of dietary survey were required for energy, protein, carbohydrate, phosphorus and iron, 13 - 19 days for fat and calcium, 25 - 29 days for vitamin A and vitamin C. Correlation coefficients between observed and true nutrient intakes were 0.71 - 0.91 for males, 0.81-0.91 for females. In conclusion, mean intakes of several nutrients can be reliably measured with the record method, using a limited number of days. Both nutrients of interest and the primary objectives should be taken account when planning method of assessment and number of replicates.

• Nutrition Research and Practice
• /
• 제13권4호
• /
• pp.323-332
• /
• 2019

BACKGROUND/OBJECTIVES: The aim of this study was to analyze specific foods influencing absolute nutrient intake and between-person variations of nutrient intake among Korean preschoolers. SUBJECTS/METHODS: This study included 2,766 participants aged 1-5 years in the 2009-2013 Korea National Health and Nutrition Examination Surveys. Dietary data were obtained from a 24-h dietary recall method. Major food sources of absolute nutrient intake were evaluated based on percent contribution of each food. To assess the contribution of specific foods to between-person variations in nutrient intake, stepwise multiple regressions were performed and cumulative $R^2$ was used. RESULTS: White rice and milk were main food sources of energy, protein, carbohydrate, phosphorus, iron, potassium, thiamin, riboflavin, and niacin. The percentage of fat contributed by milk was 21.3% which was the highest, followed by pork, soybean oil, and egg. White rice accounted for 25% and 40% of total variability in total energy and carbohydrate intakes, respectively. About 39% of variation in calcium intake was explained by milk while 40% of variation in phosphorous intake was explained by cheese. The top 10 foods contributing to between-person variations in nutrient intakes were similar with food items that mainly contributed to absolute nutrient intakes. The number of foods explaining 90% of absolute amounts of nutrient intakes varied from 28 for vitamin A to 80 for iron. CONCLUSIONS: This study identified specific foods that contributed to absolute nutrient intakes and between-person variations in nutrient intakes among Korean preschoolers. Our findings can be used to develop dietary assessment tools and establish food-based dietary guidelines for young children.

• Journal of Nutrition and Health
• /
• 제30권3호
• /
• pp.349-359
• /
• 1997

This study was designed to study sources of variability(subjects, day by day, season, day of week, sequence, number of repeated days, compliance etc.) in multiple 24-hour dietary recall method. Dietary intakes of college women in Seoul were obtained using 24-hour dietary recalls, consecutive 7 days, 4 times for 1 year. The result of this study shows that 1) the reproducibility of multiple 24-hour recalls is low(intraclass correlation coefficient<0.3), 2) the intraindividual variations of all nutrients are more than 80%, 3) the major components of variation are interindividual vriability and intraindividual variability(within person variability and methodologic error). There were small but statistically significant season and compliance effects. 4) the ratio within-person varation to between-person variation for absolute and transformed nutrient intakes except some nutrients such as vitamin A, vitamin C, energy from protein and fat etc, was less than 1.7 the minimum numbers of days needed in 24-hour dietary recalls to estimate usual intake for this group were 1 to 21 days. And the numbers of days needed to get the usual intake of an individual varied among individuals and within individuals for different nutrients, ranged from 1 days for log carbohydrate(% energy) to 470 days for Na. 6) There were greater than 0.7 correlation coefficients between the average nutrient intakes of 12 days and intakes of 28 days. Therefore, it was desirable to take the 24-hour recall more than 12 times, repeating 3 days every season.

• Journal of Nutrition and Health
• /
• 제33권4호
• /
• pp.429-437
• /
• 2000

Contributions of specific foods to absolute intake and between-person variance in 13 nutrients were examined to develop a short food frequency questionnaire (FFQ) for the Korean elderly using dietary data collected by a semiquantitative FFQ with 96 food items. The contributions of specific foods to 90% absolute nutrient intake were measured by assessing their percentage to the total consumption of a nutrient by our samples(n=98). To assess the contribution of the foods to the between-person variance in intake of each specific nutrient, stepwise multiple regression was performed. Cumulative R2 served as the measure of contribution to variation in intake. The most important food source of absolute intake was rice for energy and protein. Important foods of between person variance contribution include bread for energy and pork for protein. Important foods of absolute and variance contribution of nutrient intake were similar for fat(noodles including jajangmyun and kalguksu), calcium(anchovy and milk) and vitamin A (carrot). The number of foods necessary to account for the variation in nutrient intake among older people in Korea differ considerably by nutrient: 18 - 43 and 8-26 foods were accounted for the respective 90 and 80% of absolute intake depending on nutrients. Carbohydrates and vitamin A and C had relatively a few major sources, thus may be assessed well by a small number of foods. Conversely, iron, potassium and B vitamins appear to need longer lists of foods. Fewer numbeer (6 - 12 and 4 - 9) of foods were required for the corresponding percentages of between-person variation for all nutrients. Depending on nutrients, 0.980-0.995 and 0.924-0.987 were respective correlation coefficients of nutrient intakes measured by 96 food items with those by lists of foods for 90% and 80% of absolute intake contribution. These findings suggest that an incomplete food list on the basis of its contribution to absolute and between person variation intakes may still be effective in discriminating among individuals. The results of this study may be useful in the design and use of dietary questionnaire.

• Journal of Nutrition and Health
• /
• 제16권4호
• /
• pp.253-262
• /
• 1983

A survey was undertaken to investigate relationship between nutritional status and physical growth and behavior of school children. Dietary intakes, environmental factors, physical growth, personality, and cognitive development were measured in 323 children of 4 th and 6th grader in the urban and rural arcas. The results are summarized as follows : 1) The average intakes of the food groups and nutrients except ascorbic acid were lower in rural children. Comparing the intakes of the rural children with RDA of the Korean children, 64.0% of them in protein, 99.3% in calcium, 84.6% in iron, and 73.5% in riboflavin consumed less than 75% of RDA. Environmental factors were significantly related to the nutrient intakes 2) Height, weight, and head circumference were significantly related to the nutrient intakes. Retarded growth due to malnutrition was supposed in the $rural^{1)}$ area. 3) Some domains of personality were significantly related to nutrient intakes. 4) Environmental factors, physical growth, and nutrient intakes made independent contribution to variation in cognitive performance and their relative importance depended on the particular cognitive domain when stepwise multiple regression analyses were undertaken. Environmental stimulation was largely associated with verbal usage, and economic status and nutrient intakes with numerical reasoning. Above findings support that nutritional deprivation retards brain growth and performance on various cognitive dimensions of children. Therefore, amelioration of the several adverse social, economical, environmental influences as well as the improvement of dietary intake is required to bring about a substantial enhancement of the physical growth and the mental development of children.

• 대한지역사회영양학회지
• /
• 제3권1호
• /
• pp.62-75
• /
• 1998

This study was conducted to reveal nutrient intakes and factors affecting the nutritional status of elderly women in a rural area. The data of dietary intakes were obtained using 24hour recall data which were collected from 244 women subjects older than fifty years old. The data from the questionnaire regarding eating habits were obtained through interview. The education level and economic status of the subjects in this study were very low and education level(p<0.001), occupation(p<0.001), marital status(p<0.001), family size(p<0.05) and smoking habit(p<0.05) were significantly different among different age groups. The nutrient intakes of all age groups were not adequate to RDA level-specially, micronutrient intakes were lower in those in their sixties compared to those in their fifties. Important factors associated with variation in nutrient intakes of subjects were beef preference, regular eating habits, and education level. Therefore it is necessary to focus on subjects with low education levels and low income in order to improve the health and nutritional atatus of the elderly in rural areas. It is necessary to prepare a nutritional education program to establish and maintain good eating habits of the elderly in rural areas.

• 한국식품영양과학회지
• /
• 제26권6호
• /
• pp.1215-1220
• /
• 1997

This study was undertaken to estimate heath status, meal management, and seasonal variation of nutrient intake of rural women. The study was carried out in three seasons ; farming season(June), harvest season(October), nonfarming season(February). General characteristics, health status, and meal management of subjects were assessed using questionnaire and interview. Nutrient intake was measured by 24hr recall. Only 39.5% of subjects felt healthy. 21.1% of subjects often skipped meal each day. In farming & harvest seasons 92.1% of subjects participated in agriculture but 78.9% of subjects had the same or less appetite and 63.2% of subjects ate the same or less than usual. The mean intakes of energy and riboflavin in all seasons, calcium in June & February, and protein, vitamin A, and thiamin in February were below Recommended Dietary Allowances(RDA) for Koreans. All nutrient intake was significantly low in February but was not significantly different between in June and October.

• Nutrition Research and Practice
• /
• 제5권3호
• /
• pp.266-274
• /
• 2011

Accurate assessment of nutrient adequacy of a population should be based on usual intake distribution of that population. This study was conducted to adjust usual nutrient intake distributions of a single 24-hour recall in 2001 Korean National Health and Nutrition Surveys (KNHNS) in order to determine the magnitude of limitations inherent to a single 24-hour recall in assessing nutrient intakes of a population. Of 9,960 individuals who provided one 24-hour recall in 2001 KNHNS, 3,976 subjects provided an additional one-day 24-hour recall in 2002 Korean National Nutrition Survey by Season (KNNSS). To adjust for usual intake distribution, we estimated within-individual variations derived from 2001 KNHNS and 2002 KNNSS using the Iowa State University method. Nutritionally at risk population was assessed in reference to the Dietary Reference Intakes for Koreans (KDRIs). The Korean Estimated Average Requirement (Korean EAR) cut-point was applied to estimate the prevalence of inadequate nutrient intakes except for iron intakes, which were assessed using the probability approach. The estimated proportions below Korean EAR for calcium, riboflavin, and iron were 73%, 41%, and 24% from usual intake distribution and 70%, 51%, and 39% from one-day intake distribution, respectively. The estimated proportion of sodium intakes over the Intake Goal of 2,000 mg/day was 100% of the population after adjustment. The energy proportion from protein was within Korean Acceptable Macronutrient Distribution Ranges (Korean AMDR), whereas that of carbohydrate was higher than the upper limit and that of fat was below the lower limit in the subjects aged 30 years or older. According to these results, the prevalence of nutritional inadequacy and excess intake is over-estimated in Korea unless usual intake distributions are adjusted for one-day intakes of most nutrients.