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Biomedical subjects

A E Field

Publications and source records attributed to A E Field.

At least 19 recordsLinked to original sources

Impact of overweight on the risk of developing common chronic diseases during a 10-year period.

BACKGROUND: Overweight adults are at an increased risk of developing numerous chronic diseases. METHODS: Ten-year follow-up (1986-1996) of middle-aged women in the Nurses' Health Study and men in the Health Professionals Follow-up Study to assess the health risks associated with overweight. RESULTS: The risk of developing diabetes, gallstones, hypertension, heart disease, and stroke increased with severity of overweight among both women and men. Compared with their same-sex peers with a body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) between 18.5 and 24.9, those with BMI of 35.0 or more were approximately 20 times more likely to develop diabetes (relative risk [RR], 17.0; 95% confidence interval [CI], 14.2-20.5 for women; RR, 23.4; 95% CI, 19.4-33.2 for men). Women who were overweight but not obese (ie, BMI between 25.0 and 29.9) were also significantly more likely than their leaner peers to develop gallstones (RR, 1.9), hypertension (RR, 1.7), high cholesterol level (RR, 1.1), and heart disease (RR, 1.4). The results were similar in men. CONCLUSIONS: During 10 years of follow-up, the incidence of diabetes, gallstones, hypertension, heart disease, colon cancer, and stroke (men only) increased with degree of overweight in both men and women. Adults who were overweight but not obese (ie, 25.0 < or = BMI < or = 29.9) were at significantly increased risk of developing numerous health conditions. Moreover, the dose-response relationship between BMI and the risk of developing chronic diseases was evident even among adults in the upper half of the healthy weight range (ie, BMI of 22.0-24.9), suggesting that adults should try to maintain a BMI between 18.5 and 21.9 to minimize their risk of disease.

Body Mass Index↗

Risk of overweight among adolescents who were breastfed as infants.

CONTEXT: Overweight during adolescence predicts short- and long-term morbidity as well as obesity in adulthood. The prevalence of overweight among adolescents is high and continues to increase. Physiological and behavioral mechanisms and preliminary epidemiologic data suggest that breastfeeding could lower the risk of subsequent obesity in adolescence. OBJECTIVE: To examine the extent to which overweight status among adolescents is associated with the type of infant feeding (breast milk vs infant formula) and duration of breastfeeding. DESIGN, SETTING, AND SUBJECTS: Survey of 8186 girls and 7155 boys, aged 9 to 14 years, who are participants in the Growing Up Today Study, a nationwide cohort study of diet, activity, and growth. In the fall of 1996 we mailed a questionnaire to each of the subjects, and in the spring of 1997, we mailed a supplemental questionnaire to their mothers, who are participants in the Nurses' Health Study II. MAIN OUTCOME MEASURE: Overweight status defined as body mass index exceeding the 95th percentile for age and sex from US national data. RESULTS: In the first 6 months of life, 9553 subjects (62%) were only or mostly fed breast milk, and 4744 (31%) were only or mostly fed infant formula. A total of 7186 subjects (48%) were breastfed for at least 7 months while 4613 (31%) were breastfed for 3 months or less. At ages 9 to 14 years, 404 girls (5%) and 635 boys (9%) were overweight. Among subjects who had been only or mostly fed breast milk, compared with those only or mostly fed formula, the odds ratio (OR) for being overweight was 0.78 (95% confidence interval [CI], 0.66-0.91), after adjustment for age, sex, sexual maturity, energy intake, time watching television, physical activity, mother's body mass index, and other variables reflecting social, economic, and lifestyle factors. Compared with subjects who had been breastfed for 3 months or less, those who had been breastfed for at least 7 months had an adjusted OR for being overweight of 0.80 (95% CI, 0.67-0.96). Timing of introduction of solid foods, infant formula, or cow's milk was not related to risk of being overweight. CONCLUSION: Infants who were fed breast milk more than infant formula, or who were breastfed for longer periods, had a lower risk of being overweight during older childhood and adolescence.

Adolescent↗

Cross-sectional measurement of nutrient intake among adolescents in 1996.

BACKGROUND: Many components are involved in an assessment of diet and health among youth. To address these issues and document the major contributions of fat, fiber, vitamins, and minerals to the diet, we analyzed baseline cross-sectional data from a cohort of 16,882 youth. METHODS: Cross-sectional analyses were conducted on the Growing Up Today Study dietary data reported by 16,882 9- to 14-year-olds in 1996. The adolescent food frequency questionnaire was used to assess this age group's eating habits. Arithmetic means and standard deviations were calculated on energy-adjusted and unadjusted data. RESULTS: Mean intake (including vitamin/mineral supplementation) for all nutrients met 100% of the RDAs, except calcium for girls. Comparing the servings of foods with the USDA Food Pyramid, neither boys nor girls met recommended number of servings except for dairy. Overweight participants consumed fewer kilocalories and lower levels of nutrients than their nonoverweight peers. CONCLUSION: These cross-sectional data from 1996 indicate that this cohort is consuming foods and nutrients comparable with national data of less fat and more carbohydrates in their diet. Overweight participants have similar dietary patterns except for total energy. The cohort's diet (with vitamin/mineral supplementation) is meeting the RDAs, but actual foods consumed suggest a lack of balance in the diet.

Adolescent↗

Comparing physical activity questionnaires for youth: seasonal vs annual format.

BACKGROUND: In large cohort studies of older children, self-report is the only practical way to assess physical activity. Assessing usual activity over the entire year is desirable, but children and adolescents may overestimate activities with high seasonal variability. Use of questionnaires in which individuals report each activity by season may improve accuracy. METHODS: A total of 6782 girls and 5110 boys, aged 9-14 years in 1996, completed self-administered activity questionnaires in 1996 and in 1997. In 1996, participants reported the average time spent in each of 17 activities during the previous 12 months; in 1997, we also asked for the average time spent in the previous year, but within each of the four seasons. RESULTS: Girls reported a median of 12.8 hours/week total activity in 1996 and 10.4 hours/week in 1997. For boys, the estimates were 15.5 hours/week and 13.4 hours/week, respectively. Girls and boys within 1-year age strata (e.g., comparison of 10-year olds in 1996 with 10-year olds in 1997) reported an average of 3.7 and 3.1 fewer hours per week, respectively, on the 1997 seasonal format versus the 1996 annual format questionnaire. In longitudinal analyses, the difference between the annual and the seasonal estimates was greater if participants did the activity in fewer seasons in 1997. CONCLUSIONS: In comparison to an annual format questionnaire, a seasonal format questionnaire may improve accuracy of self-report of physical activity by reducing over-reporting of activities in which pre-adolescents and adolescents engage in fewer seasons.

Adolescent↗

The effect of social desirability trait on self-reported dietary measures among multi-ethnic female health center employees.

PURPOSE: To evaluate the effect of social desirability trait, the tendency to respond in a manner consistent with societal expectations, on self-reported fruit, vegetable, and macronutrient intake. METHODS: A 61-item food frequency questionnaire (FFQ), 7-item fruit and vegetable screener, and a single question on combined fruit and vegetable intake were completed by 132 female employees at five health centers in eastern Massachusetts. Intake of fruit and vegetables derived from all three methods and macronutrients from the FFQ were fit as dependent variables in multiple linear regression models (overall and by race/ethnicity and education); independent variables included 3-day mean intakes derived from 24-hour recalls (24HR) and score on the 33-point Marlowe-Crowne Social Desirability scale (the regression coefficient for which reflects its effect on estimates of dietary intake based on the comparison method relative to 24HR). RESULTS: Results are based on the 93 women with complete data and FFQ-derived caloric intake between 450 and 4500 kcal/day. In women with college education, FFQ-derived estimates of total caloric were associated with under-reporting by social desirability trait (e.g., the regression coefficient for total caloric intake was -23.6 kcal/day/point in that group versus 36.1 kcal/day/point in women with education less than college) (difference = 59.7 kcal/day/point, 95% confidence interval (CI) = 13.2, 106.2). Except for the single question on which women with college education tended to under-report (difference =.103 servings/day/point, 95% CI = 0.003, 0.203), there was no association of social desirability trait with self-reported fruit and vegetable intake. CONCLUSIONS: The effect of social desirability trait on FFQ reports of macronutrient intake appeared to differ by education, but not by ethnicity or race. The results of this study may have important implications for epidemiologic studies of diet and health in women.

Adult↗

Relationship of a large weight loss to long-term weight change among young and middle-aged US women.

OBJECTIVE: To assess the prevalence of clinically significant weight loss among women and whether this is associated with smaller long-term weight gains. DESIGN: Six-year follow-up of young and middle-aged women in the Nurses' Health Study II. SUBJECTS: A total of 47,515 women who did not report a pregnancy, or a diagnosis of cancer or cardiovascular disease any time between 1989 and 1995. MEASUREMENTS: Self-reported weights in 1989, 1991, 1993 and 1995, dietary intake, physical activity, inactivity, history of weight cycling and smoking. RESULTS: Between 1989 and 1991, 9% of the women lost > or =5% of their 1989 weight (6% lost 5--9.9% and 3% lost > or =10%). The proportion who lost > or =10% of their weight increased with category of body mass index (BMI, kg/m(2)) from 0.4% among women with a BMI <22 to 9% among women with a BMI > or =30 in 1989. Women who lost > or =5% of their weight between 1989 and 1991 gained more weight between 1991 and 1995 than their peers and the difference increased across categories of BMI in 1989. However, due to their large weight losses, women who lost > or =5% of their weight between 1989 and 1991 overall gained less weight than their peers between 1989 and 1995 (P<0.001). Moreover, women who engaged in 5 or more hours per week of vigorous physical activity gained approximately 0.5 kg less than their inactive peers (P<0.001). CONCLUSION: Although most women who lost a clinically significant amount of weight regained most of it, they gained less weight over the entire 6 y period than their peers.

Adult↗

Modification of the tear function index and its use in the diagnosis of Sjögren's syndrome.

BACKGROUND: The tear function index (TFI) has been shown to be of value in the diagnosis of patients suffering from Sjögren's syndrome. It is dependent, however, on introducing into the conjunctival fornix the correct concentration of fluorescein in at least one and a half times the normal tear volume. The stimulus and effect of this added volume on the tear dynamics is likely to vary between individuals. These factors, together with the method of performing the test, limit its general applicability. AIM: To devise a method of performing the TFI with less variability and more general applicability. To present a theoretical and in vitro assessment of the dynamics of the TFI. METHOD: The study was divided into three parts. The first part was to compare the results obtained using a prepared strip containing 1.3 microl of 0.5% fluorescein with the introduction of the same amount of fluorescein as a drop. The second part was to compare the results obtained with prepared strips with the standard method of performing the TFI, both with and without topical anaesthetic. The third part was an in vitro study of the rate of flow of graded volumes on a filter paper strip. 42 subjects with a diagnosis of Sjögren's syndrome according to the European criteria and 126 without Sjögren's syndrome were included. RESULTS: There was no significant difference between the results obtained with a prepared strip and the introduction of 1.3 microl into the eye before performing the Schirmer's test and TFI (0.1<p<0.93). There was, likewise, no significant difference between using the prepared strips and the standard method of performing the TFI (0.36<p<0.93). There was, however, less interocular difference (p=0.01) and variability (p=0.001) using the prepared strips than using a drop of fluorescein. Patients with Sjögren's syndrome had mean TFIs of 11.7 and 8.61 with upper 95% confidence values of 15 and 12 without and with topical anaesthetic, respectively. The theoretical calculation of the TFI was similar to the observed values. The in vitro results allow the filter paper to be removed from the eye at any interval and to estimate the volume of tears that the filter paper was in contact with. CONCLUSION: The proposed method of performing the TFI is easy to perform, reliable, and therefore has general applicability for primary care and general practitioners. It allows the rapid identification of subjects who may be suffering from Sjögren's syndrome.

Aged↗

Peer, parent, and media influences on the development of weight concerns and frequent dieting among preadolescent and adolescent girls and boys.

OBJECTIVE: To assess prospectively the influence of peers, parents, and the media on the development of weight concerns and frequent dieting. DESIGN: Prospective cohort study. SETTING: Questionnaires mailed annually to participants throughout the United States. PARTICIPANTS: One-year follow-up of 6770 girls and 5287 boys who completed questionnaires in 1996 and 1997 and were between 9 and 14 years of age in 1996. MAIN OUTCOME MEASURE: Onset of high levels of concern with weight and dieting frequently to control weight. RESULTS: During 1 year of follow-up, 6% of girls and 2% of boys became highly concerned with weight and 2% of girls and 1% of boys became constant dieters. Peer influence was negligible. Independent of age and body mass index, both girls (odds ratio [OR]): 1.9; 95% confidence interval [CI]: 1.1-3.1) and boys (OR: 2.7; 95% CI: 1.1-6. 4) who were making a lot of effort to look like same-sex figures in the media were more likely than their peers to become very concerned with their weight. Moreover, both girls (OR: 2.3; 95% CI: 1.1-5.0) and boys (OR: 2.6; 95% CI: 1.1-6.0) who reported that their thinness/lack of fat was important to their father were more likely than their peers to become constant dieters. CONCLUSIONS: Our results suggest that parents and the media influence the development of weight concerns and weight control practices among preadolescents and adolescents. However, there are gender differences in the relative importance of these influences.

Adolescent↗

Family dinner and diet quality among older children and adolescents.

CONTEXT: The proportion of children eating dinner with their families declines with age and has decreased over time. Few data exist concerning the nutritional effect of eating family dinner. OBJECTIVE: To examine the associations between frequency of eating dinner with family and measures of diet quality. DESIGN: Cross-sectional. SETTING: A national convenience sample. PARTICIPANTS: There were 8677 girls and 7525 boys in the study, aged 9 to 14 years, who were children of the participants in the ongoing Nurses' Health Study II. MAIN OUTCOME MEASURES: We collected data from a self-administered mailed survey, including food and nutrient intakes from a validated semiquantitative food frequency questionnaire. Main outcome measures included servings per day of selected foods and food groups, daily intakes of selected macronutrients and micronutrients, and frequency of multivitamin use. RESULTS: Approximately 17% of participants ate dinner with members of their family never or some days, 40% on most days, and 43% every day. More than half of the 9-year-olds ate family dinner every day, whereas only about one third of 14-year-olds did so. In age- and sex-adjusted logistic regression models, the odds ratios associated with a frequency of family dinner of most days compared with never or some days, or every day compared with most days, were as follows: for eating at least 5 servings per day of fruits and vegetables, 1.45 (95% confidence interval [CI], 1.37-1.53); for eating any fried foods away from home, 0.67 (95% CI, 0.64-0.70); and for drinking any soda, 0.73 (95% CI, 0.66-0.80). Multiple linear regression showed that an increased frequency of family dinner was also associated with substantially higher intake of several nutrients, including fiber, calcium, folate, iron, vitamins B6, B12, C, and E; lower glycemic load; and lower intake of saturated and trans fat as a percentage of energy. We observed little or no effect on intakes of whole dairy products, red meat, or snack foods. Patterns were similar for boys and girls. CONCLUSIONS: Eating family dinner was associated with healthful dietary intake patterns, including more fruits and vegetables, less fried food and soda, less saturated and trans fat, lower glycemic load, more fiber and micronutrients from food, and no material differences in red meat or snack foods.

Adolescent↗

Activity, dietary intake, and weight changes in a longitudinal study of preadolescent and adolescent boys and girls.

OBJECTIVE: To examine the role of physical activity, inactivity, and dietary patterns on annual weight changes among preadolescents and adolescents, taking growth and development into account. STUDY DESIGN: We studied a cohort of 6149 girls and 4620 boys from all over the United States who were 9 to 14 years old in 1996. All returned questionnaires in the fall of 1996 and a year later in 1997. Each child provided his or her current height and weight and a detailed assessment of typical past-year dietary intakes, physical activities, and recreational inactivities (TV, videos/VCR, and video/computer games). METHODS: Our hypotheses were that physical activity and dietary fiber intake are negatively correlated with annual changes in adiposity and that recreational inactivity (TV/videos/games), caloric intake, and dietary fat intake are positively correlated with annual changes in adiposity. Separately for boys and girls, we performed regression analysis of 1-year change in body mass index (BMI; kg/m(2)). All hypothesized factors were in the model simultaneously with several adjustment factors. RESULTS: Larger increases in BMI from 1996 to 1997 were among girls who reported higher caloric intakes (.0061 +/-.0026 kg/m(2) per 100 kcal/day; beta +/- standard error), less physical activity (-.0284 +/-.0142 kg/m(2)/hour/day) and more time with TV/videos/games (.0372 +/-.0106 kg/m(2)/hour/day) during the year between the 2 BMI assessments. Larger BMI increases were among boys who reported more time with TV/videos/games (.0384 +/-.0101) during the year. For both boys and girls, a larger rise in caloric intake from 1996 to 1997 predicted larger BMI increases (girls:.0059 +/-.0027 kg/m(2) per increase of 100 kcal/day; boys:.0082 +/-.0030). No significant associations were noted for energy-adjusted dietary fat or fiber. CONCLUSIONS: For both boys and girls, a 1-year increase in BMI was larger in those who reported more time with TV/videos/games during the year between the 2 BMI measurements, and in those who reported that their caloric intakes increased more from 1 year to the next. Larger year-to-year increases in BMI were also seen among girls who reported higher caloric intakes and less physical activity during the year between the 2 BMI measurements. Although the magnitudes of these estimated effects were small, their cumulative effects, year after year during adolescence, would produce substantial gains in body weight. Strategies to prevent excessive caloric intakes, to decrease time with TV/videos/games, and to increase physical activity would be promising as a means to prevent obesity.

Adolescent↗

The disease burden associated with overweight and obesity.

CONTEXT: Overweight and obesity are increasing dramatically in the United States and most likely contribute substantially to the burden of chronic health conditions. OBJECTIVE: To describe the relationship between weight status and prevalence of health conditions by severity of overweight and obesity in the US population. DESIGN AND SETTING: Nationally representative cross-sectional survey using data from the Third National Health and Nutrition Examination Survey (NHANES III), which was conducted in 2 phases from 1988 to 1994. PARTICIPANTS: A total of 16884 adults, 25 years and older, classified as overweight and obese (body mass index [BMI] > or =25 kg/m2) based on National Institutes of Health recommended guidelines. MAIN OUTCOME MEASURES: Prevalence of type 2 diabetes mellitus, gallbladder disease, coronary heart disease, high blood cholesterol level, high blood pressure, or osteoarthritis. RESULTS: Sixty-three percent of men and 55% of women had a body mass index of 25 kg/m2 or greater. A graded increase in the prevalence ratio (PR) was observed with increasing severity of overweight and obesity for all of the health outcomes except for coronary heart disease in men and high blood cholesterol level in both men and women. With normal-weight individuals as the reference, for individuals with BMIs of at least 40 kg/m2 and who were younger than 55 years, PRs were highest for type 2 diabetes for men (PR, 18.1; 95% confidence interval [CI], 6.7-46.8) and women (PR, 12.9; 95% CI, 5.7-28.1) and gallbladder disease for men (PR, 21.1; 95% CI, 4.1-84.2) and women (PR, 5.2; 95% CI, 2.9-8.9). Prevalence ratios generally were greater in younger than in older adults. The prevalence of having 2 or more health conditions increased with weight status category across all racial and ethnic subgroups. CONCLUSIONS: Based on these results, more than half of all US adults are considered overweight or obese. The prevalence of obesity-related comorbidities emphasizes the need for concerted efforts to prevent and treat obesity rather than just its associated comorbidities.

Adult↗

Weight cycling, weight gain, and risk of hypertension in women.

To assess prospectively the relation between body mass index, weight gain, repeated intentional weight losses, and the risk of self-reported hypertension, the authors studied 46,224 women who were participants in the Nurses Health Study II, who were free of hypertension in 1993, and who completed questions on intentional weight losses between 1989 and 1993. Women who reported they had intentionally lost > or =20 lbs (9 kg) > or =3 times were classified as severe weight cyclers. Women who had intentionally lost > or =10 lbs (4.5 kg) > or =3 times, but who did not meet the criteria for severe weight cycling, were classified as mild weight cyclers. Between 1993 and 1995, 1,107 incident cases of diagnosed hypertension were reported. Body mass index and weight gain, but not weight cycler status, were independently associated with the development of hypertension. For each 10 lb (4.5 kg) gain in weight between 1989 and 1993, the risk of hypertension increased 20% (odds ratio (OR) = 1.20, 95% confidence interval (CI) 1.15, 1.24). After adjustment for body mass index and weight gain, the risks associated with mild weight cycling (OR = 1.15, 95% CI 1.00, 1.33) and severe weight cycling (OR = 1.13, 95% CI 0.79, 1.61) were small and not significant. Thus, the results of this study offer support for the current weight guidelines and provide further evidence of the health risks associated with excessive weight and weight gain. However, these data do not suggest an independent effect of weight cycling on risk of hypertension.

Adult↗

Relation of peer and media influences to the development of purging behaviors among preadolescent and adolescent girls.

OBJECTIVE: To assess prospectively the relation of peer and media influences on the risk of development of purging behaviors. DESIGN: Prospective cohort study. SETTING: One year follow-up of 6982 girls aged 9 to 14 years in 1996 who completed questionnaires in 1996 and 1997 and reported in 1996 that they did not use vomiting or laxatives to control weight. MAIN OUTCOME MEASURE: Self-report of using vomiting or laxatives at least monthly to control weight. RESULTS: During 1 year of follow-up, 74 girls began using vomiting or laxatives at least monthly to control weight. Tanner stage of pubic hair development was predictive of beginning to purge (odds ratio [OR] = 1.8; 95% confidence interval [CI], 1.3-2.4). Independent of age and Tanner stage of pubic hair development, importance of thinness to peers (OR = 2.3; 95% CI, 1.8-3.0) and trying to look like females on television, in movies, or in magazines (OR= 1.9; 95% CI, 1.6-2.3) were predictive of beginning to purge at least monthly. Regardless of the covariates included in the logistic regression model, the risk of beginning to purge increased approximately 30% to 40% per 1-category increase in frequency of trying to look like females on television, in movies, or in magazines. CONCLUSIONS: Both peers and popular culture, independent of each other, exert influence on girls' weight control beliefs and behaviors. Therefore, to make eating disorder prevention programs more effective, efforts should be made to persuade the television, movie, and magazine industries to employ more models and actresses whose weight could be described as healthy, not underweight.

Adolescent↗

Impact of a school-based interdisciplinary intervention on diet and physical activity among urban primary school children: eat well and keep moving.

OBJECTIVE: To evaluate the impact of a school-based interdisciplinary health behavior intervention on diet and physical activity among children in grades 4 and 5. DESIGN: A quasiexperimental field trial with 6 intervention and 8 matched control schools. Outcomes were assessed longitudinally using preintervention (fall 1995) and follow-up (spring 1997) student survey food frequency and activity measures and follow-up 24-hour recall measures of diet and activity. Change was also assessed using yearly repeated cross-sectional surveys of all grade 5 students from 1995 through 1997. PARTICIPANTS: Longitudinal data were collected from 479 students initially in grade 4 in Baltimore, Md, public schools; 91% were African American. Repeated 24-hour recall measures in 1997 were collected for a random subsample of 336 students. Cross-sectional survey data were collected from all grade 5 students in 1995,1996, and 1997 (n = 2103). INTERVENTION: The Eat Well and Keep Moving Program was taught by classroom teachers over 2 years in math, science, language arts, and social studies classes. Materials provided links to school food services and families and provided training and wellness programs for teachers and other staff members. Intervention materials focused on decreasing consumption of foods high in total and saturated fat and increasing fruit and vegetable intake, as well as reducing television viewing and increasing physical activity. MAIN OUTCOME MEASURES: Dietary intake and physical activity measured via repeated 24-hour recall were primary end points, with additional food frequency and activity measures. RESULTS: The 24-hour recall measures indicated that, after controlling for baseline covariates, the percentages of total energy from fat and saturated fat were reduced among students in intervention compared with control schools (-1.4%; 95% confidence interval [CI], -2.8 to -0.04; P = .04 and -0.60%; 95% CI, -1.2 to -0.01; P = .05). There was an increase in fruit and vegetable intake (0.36 servings/4184 kJ; 95% CI, 0.10-0.62; P=.01), in vitamin C intake (8.8 mg/4184 kJ; 95% CI, 2.0-16; P=.01), and in fiber consumption (0.7 g/4184 kJ; 95% CI, 0.0-1.4; P=.05). Television viewing was marginally reduced (-0.55 h/d; 95% CI, -1.04 to 0.04; P=.06). Analysis of longitudinal and repeated cross-sectional food frequency data indicated similar significant decreases in the percentages of total energy from fat and saturated fat. CONCLUSION: Evaluation of the Eat Well and Keep Moving Program indicates effectiveness in improving dietary intake of students and reducing television viewing.

Baltimore↗

Reproducibility and validity of a food frequency questionnaire among fourth to seventh grade inner-city school children: implications of age and day-to-day variation in dietary intake.

OBJECTIVE: To assess the reproducibility and validity of a semiquantitative food frequency questionnaire (FFQ) to classify children and adolescents in terms of daily servings of fruits and vegetables and intake of calories, protein, fat, carbohydrate, dietary fibre, vitamin C, phosphorous, calcium and iron. DESIGN: FFQs were collected in the autumn of 1993 and 1994. Four 24-hour diet recalls were collected during the same 1-year period and their mean was compared to the FFQ diet estimates. SETTING: Low income, inner-city state schools. SUBJECTS: A sample of 109 inner-city fourth to seventh grade students. RESULTS: The 1-year reproducibility of the FFQ, assessed with Spearman correlations, was lower among the fourth and fifth (range: r=-0.26 to 0.40) than the sixth and seventh grade students (range: r=0.18-0.47). After adjusting for day-to-day variation in dietary intake, for most nutrients and foods the correlations between the FFQ and the 24-hour recalls remained greater among the junior high school students (fourth to fifth grade range: r=0.0-0.42; sixth to seventh grade range: r=0.07-0.76). CONCLUSIONS: Inner-city sixth and seventh grade students demonstrated the ability to provide valid estimates of intake of calories, carbohydrate, calcium, phosphorous, iron and vitamin C over the past year. However, children in the fourth and fifth grades experienced some difficulty in completing the FFQ. Our results suggest that, before using this instrument with fourth and fifth grade children, investigators should assess whether study participants can think abstractly and are familiar with the concept of 'average intake'.

Child↗

Validity of a food frequency questionnaire in assessing nutrient intakes of low-income pregnant women.

OBJECTIVE: In 1989, a validation study of eight nutrients was performed on a modified food frequency questionnaire (FFQ) specifically designed for low-income pregnant women. The purpose of this study was to broaden the scope of the previous study by assessing the validity of the FFQ for 17 additional nutrients. METHODS: The Pregnancy Food Frequency Questionnaire (PFFQ) was administered to a sample of 295 low-income, pregnant women aged 14-43 years living in Massachusetts. A randomly selected subsample of 101 women who provided at least one diet recall and reported intake of less than 4,500 calories were included in this analysis. RESULTS: Mean intake of 25 nutrients as assessed by one administration of the PFFQ and up to three diet recalls collected over 1 month were similar. Unadjusted correlation coefficients between nutrient intake measured by diet recalls and the questionnaire ranged from .28 (carotene) to .61 (folate). After adjusting for energy intake the correlations ranged from .03 (B12) to .46 (folate). The correlations corrected for day-to-day variation were higher, ranging from .07 (B12) to .90 (zinc). The mean correlation was .47 and there were 54% over .40. CONCLUSIONS: A food frequency questionnaire for English-speaking, low-income, pregnant women can provide maternal and child health practitioners and researchers a valid estimate of diet across a wide range of nutrients.

Adolescent↗