Measures
Dietary intake
Three nonconsecutive 24-h dietary recalls that included 2 weekdays and 1 weekend day were conducted, and the children were the primary respondents. Nine validation studies have provided support for the use of 24-h dietary recalls in children as young as third-grade children (15–23), and 24-h dietary recalls are considered the most appropriate method to collect dietary data from diverse cultural groups (24). Registered dietitians collected the recalls by using standard protocols in the Nutrition DataSystemforResearch(NDS-R,versions4.01and4.02)(25). In addition, for each meal or snack, the children were asked whether they participated in any of the following activities while eating: watching television, watching a videotape or movie on a videocassette recorder or video disk, playing video games or playing on a computer, watching a movie at the theatre, doing homework, reading (other than for homework), playing inside, playing outside, or riding in a car, van, bus, or truck. This information was linked to the data on the foods and nutrients consumed during each meal or snack. The first recall was conducted face-to-face, and the remaining 2 recalls were collected over the telephone. The children’s mothers were consulted on both the face-to-face and telephone recalls to clarify food details, foodpreparation methods, or brand names that the children could not recall. To check the interinterviewer reliability of the dietary recalls, a subsample of 22 (5%) telephone recalls were taperecorded and reentered by a second dietitian.
The NDS-R database (versions 4.01 and 4.02) is derived from the US Department of Agriculture Handbook No. 8 and includes many Hispanic food items (26). Average intakes of energy; percentages of energy from fat; energy densities; and average intakes of soda, children’s cereals, sweets and snack foods, fast foods, and fruit and vegetables were calculated. Energy density calculations included all foods and all beverages with 1.20 kJ/serving. Soda included all varieties of soda, both diet and regular. Children’s cereals included those that had a character designedtoappealtochildrenonthebox.Sweetsandsnackfoods included ice cream, doughnuts, cookies, cakes, pies, candy, chips, popcorn, crackers, pretzels, and other salty snack foods. Fast foods included all foods and beverages purchased from national fast food restaurant chains. Fruits and vegetables were defined according to the 5-A-Day criteria (27). Accordingly, fresh,frozen,orcannedfruitand100%fruitjuiceswereincluded, but fruit dishes that contained 30% of energy from fat were not included. Likewise, vegetables included all fresh, frozen, or canned vegetables. Fried or pickled vegetables and vegetable dishes that contained 30% of energy from fat were not included.
Height and weight
Standing height without shoes was measured twice, to the nearest millimeter, by using a portable, direct-reading stadiometer. If the 2 measures differed by 5 mm, a third measure was obtained.Bodyweightwasmeasuredtwice,tothenearest0.1kg, byusingdigitalscaleswhilethesubjectsworelightindoorclothing but no shoes. If the 2 measures differed by 0.2 kg, a third measure was obtained. The mean of the 2 measures, or the median of the 3 measures, was used in the analysis. BMI was calculated as weight (in kg) divided by the square of height (in m).
Demographic variables
In the third-grade sample, the parents reported their children’s age, sex, and ethnicity during telephone interviews. In the fifthgrade sample, the mothers reported this information during a face-to-face interview.
Statistics
Because the children were sampled from 2 different populations, all analyses were calculated independently for each sample. Prior to our primary analyses, we examined weekday– weekend day effects by using multilevel analysis of variance, which showed significant heterogeneity (defined a priori as P 0.10) between weekend days and weekdays in energy intake and percentageofenergyfromfatwiththetelevisiononoroffinboth samples (F ranged from 3.57 to 15.16, all P 0.06). Therefore, all subsequent analyses were performed separately for weekend dayandweekdaydata,oreffectsforweekenddaycomparedwith weekday were included in the analyses. The average of the 2 weekdays were used in all weekday analyses.
First, the amount of food consumed during television viewing was described by the number of meals consumed with the television on or off, the amount of energy consumed with the television on or off, and the number of servings, based on standard US Department of Agriculture serving sizes, of foods in each of the6foodcategoriesthatwereconsumedduringtelevisionviewing.Apairedsamplesigntestwasusedtoexaminedifferencesin the percentage of meals consumed during television viewing between weekdays and weekend days. To examine the association between children’s food consumption during television viewing and their weight status, Spearman correlations were calculated between BMI and both pe
MeasuresDietary intakeThree nonconsecutive 24-h dietary recalls that included 2 weekdays and 1 weekend day were conducted, and the children were the primary respondents. Nine validation studies have provided support for the use of 24-h dietary recalls in children as young as third-grade children (15–23), and 24-h dietary recalls are considered the most appropriate method to collect dietary data from diverse cultural groups (24). Registered dietitians collected the recalls by using standard protocols in the Nutrition DataSystemforResearch(NDS-R,versions4.01and4.02)(25). In addition, for each meal or snack, the children were asked whether they participated in any of the following activities while eating: watching television, watching a videotape or movie on a videocassette recorder or video disk, playing video games or playing on a computer, watching a movie at the theatre, doing homework, reading (other than for homework), playing inside, playing outside, or riding in a car, van, bus, or truck. This information was linked to the data on the foods and nutrients consumed during each meal or snack. The first recall was conducted face-to-face, and the remaining 2 recalls were collected over the telephone. The children’s mothers were consulted on both the face-to-face and telephone recalls to clarify food details, foodpreparation methods, or brand names that the children could not recall. To check the interinterviewer reliability of the dietary recalls, a subsample of 22 (5%) telephone recalls were taperecorded and reentered by a second dietitian.The NDS-R database (versions 4.01 and 4.02) is derived from the US Department of Agriculture Handbook No. 8 and includes many Hispanic food items (26). Average intakes of energy; percentages of energy from fat; energy densities; and average intakes of soda, children’s cereals, sweets and snack foods, fast foods, and fruit and vegetables were calculated. Energy density calculations included all foods and all beverages with 1.20 kJ/serving. Soda included all varieties of soda, both diet and regular. Children’s cereals included those that had a character designedtoappealtochildrenonthebox.Sweetsandsnackfoods included ice cream, doughnuts, cookies, cakes, pies, candy, chips, popcorn, crackers, pretzels, and other salty snack foods. Fast foods included all foods and beverages purchased from national fast food restaurant chains. Fruits and vegetables were defined according to the 5-A-Day criteria (27). Accordingly, fresh,frozen,orcannedfruitand100%fruitjuiceswereincluded, but fruit dishes that contained 30% of energy from fat were not included. Likewise, vegetables included all fresh, frozen, or canned vegetables. Fried or pickled vegetables and vegetable dishes that contained 30% of energy from fat were not included.Height and weightStanding height without shoes was measured twice, to the nearest millimeter, by using a portable, direct-reading stadiometer. If the 2 measures differed by 5 mm, a third measure was obtained.Bodyweightwasmeasuredtwice,tothenearest0.1kg, byusingdigitalscaleswhilethesubjectsworelightindoorclothing but no shoes. If the 2 measures differed by 0.2 kg, a third measure was obtained. The mean of the 2 measures, or the median of the 3 measures, was used in the analysis. BMI was calculated as weight (in kg) divided by the square of height (in m).Demographic variablesIn the third-grade sample, the parents reported their children’s age, sex, and ethnicity during telephone interviews. In the fifthgrade sample, the mothers reported this information during a face-to-face interview.StatisticsBecause the children were sampled from 2 different populations, all analyses were calculated independently for each sample. Prior to our primary analyses, we examined weekday– weekend day effects by using multilevel analysis of variance, which showed significant heterogeneity (defined a priori as P 0.10) between weekend days and weekdays in energy intake and percentageofenergyfromfatwiththetelevisiononoroffinboth samples (F ranged from 3.57 to 15.16, all P 0.06). Therefore, all subsequent analyses were performed separately for weekend dayandweekdaydata,oreffectsforweekenddaycomparedwith weekday were included in the analyses. The average of the 2 weekdays were used in all weekday analyses.First, the amount of food consumed during television viewing was described by the number of meals consumed with the television on or off, the amount of energy consumed with the television on or off, and the number of servings, based on standard US Department of Agriculture serving sizes, of foods in each of the6foodcategoriesthatwereconsumedduringtelevisionviewing.Apairedsamplesigntestwasusedtoexaminedifferencesin the percentage of meals consumed during television viewing between weekdays and weekend days. To examine the association between children’s food consumption during television viewing and their weight status, Spearman correlations were calculated between BMI and both pe
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