Obesity status transitions across the elementary years: use of Markov chain modelling

OBJECTIVE

The objective of this study was to assess overweight and obesity status transition probabilities using first-order Markov transition models applied to elementary school children.

METHOD

Complete longitudinal data across 11 assessments were available from 1494 elementary school children (from 7599 students in 41 out of 45 schools in a Southeast Texas school district) from kindergarten to the beginning of the fifth grade. Heights and weights were measured by trained school nurses using standard procedures at the beginning and end of each school year for the 11 consecutive assessments. To estimate the transition probabilities, first-order three-state (healthy weight, overweight and obese) Markov transition models were fit to the longitudinal weight status data of all assessment periods.

RESULTS

While there was a gradual shift to more children in the overweight or obese category over 5 years, children were most likely to stay in the same weight category as the previous assessment. A consistent seasonal difference in the probability of changing weight status category was seen, with a greater probability of becoming overweight and obese during the summer compared with the school year. The transition probabilities to obesity were higher among boys, Hispanic and non-Hispanic Black, and lower socioeconomic status children.

CONCLUSIONS

This study provides the first application of a Markov transition model to child weight status data. The transitions into the overweight and obese categories were small, but persistent, with smaller percentages transitioning out of overweight or obese. Early monitoring and summer intervention strategies are needed to prevent the slow, but relentless, transition into the overweight and obese categories.

The IDEFICS intervention trial to prevent childhood obesity: design and study methods

INTRODUCTION

One of the major research dimensions of the Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) study involved the development, implementation and evaluation of a setting-based community-oriented intervention programme for primary prevention of childhood obesity. In this supplement of Obesity Reviews, a compilation of key results of the IDEFICS intervention is packaged in a series of complementary papers.

OBJECTIVE

This paper describes the overall design and methods of the IDEFICS intervention in order to facilitate a comprehensive reading of the supplement. In addition, some 'best practice' examples are described.

RESULTS

The IDEFICS intervention trial was conducted to assess whether the IDEFICS intervention prevented obesity in young children aged 2 to 9.9 years. The study was a non-randomized, quasi-experimental trial with one intervention matched to one control region in each of eight participating countries. The intervention was designed following the intervention mapping framework, using a socio-ecological theoretical approach. The intervention was designed to address several key obesity-related behaviours in children, parents, schools and community actors; the primary outcome was the prevalence of overweight/obesity according to the IOTF criteria based on body mass index. The aim was to achieve a reduction of overweight/obesity prevalence in the intervention regions. The intervention was delivered in school and community settings over a 2-year period. Data were collected in the intervention and control cohort regions at baseline and 2 years later.

CONCLUSION

This paper offers an introductory framework for a comprehensive reading of this supplement on IDEFICS intervention key results.

Should the IDEFICS outcomes have been expected?

The Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) study evaluated with a large sample a comprehensive carefully planned obesity prevention intervention targeting multiple levels of influence that were culturally adapted to the situations in eight European countries. Despite the great effort and attention to detail, the IDEFICS study did not achieve its targeted adiposity or behaviour change objectives. Should we be surprised that the IDEFICS trial did not have its intended effects? We think not, and would have been surprised if it did. Recent research has revealed the lack of consistent meaningful relationships between several apparently obesogenic behaviours and adiposity, weak or no relationships among behavioural change procedures, mediating variables and targeted behaviours and inadequate attention to moderating effects. Future obesity prevention interventions would benefit from a more thorough understanding of the complex relationships that have been hypothesized and the interrelationships with biological factors. While systems modelling has been proposed as providing the solution, important less complex identification of new constructs, new relationships and community interventions are still needed, both to find innovative solutions and to provide input into the systems models. We should question results from cross-sectional studies and be satisfied only with longitudinal or experimental tests of relationships.

Validation of a web-based questionnaire to assess the dietary intake of Brazilian children aged 7-10 years

BACKGROUND

The Food Intake and Physical Activity of School Children (CAAFE) comprises an online questionnaire to self-report diet and physical activity of Brazilian schoolchildren.

BACKGROUND

The present study aimed to assess the validity (matches, omissions and intrusions) and moderating factors of the CAAFE.

METHODS

Direct observation was made of foods consumed (five public schools) and child self-reporting on the CAAFE. Additional data included school grade, gender, body mass index, completion of food diary, socioeconomic status and access to computer. Data were analysed using regression.

RESULTS

In total, 602 children participated in the study [mean (SD) age 9.5 (1.24) years; 53.6% boys]. On average, there were 43% matches, 29% intrusions and 28% omissions. Matches doubled in third grade compared to the second grade (P = 0.004); matches almost tripled for afternoon snack compared to morning snack (P < 0.001); and matches were 69% higher for children with access to a computer at home (P < 0.01). Intrusions decreased by almost one-half in fifth compared to fourth grades (P = 0.004). Omissions declined significantly in the third and fourth grades but increased in the fifth grade. Omissions were 47% lower for children in the highest income and lower among children who completed the food diary. No differences were found for gender or body mass index.

CONCLUSIONS

Children older than 8 years old, who owned a computer and completed a food diary, performed better in the CAAFE. A high incidence of disagreement was found in relation to the schools and the type of meal. Overall matches (43%), intrusions (29%) and omissions (28%) indicate that further studies are required to improve the validity of the CAAFE.

Qualitative analysis of the contributions of nutritionists to the development of an online instrument for monitoring the food intake of schoolchildren

BACKGROUND

The Consumo Alimentar e Atividade Fisica de Escolares (CAAFE) questionnaire is an online research tool that has been developed to enable the self-report of physical activity and diet by Brazilian schoolchildren aged 7-10 years. Formative research was conducted with nutritionists during the development of the web-based questionnaire. The suggestions and insights obtained were used to design a tool to monitor schoolchildren's food consumption based on the concept of healthy and unhealthy food indicators. The present study aimed to report the focus group discussions conducted with nutritionists concerning the CAAFE questionnaire.

METHODS

Focus group discussions were conducted using a semi-structured questionnaire, and these were then analysed thematically.

RESULTS

Twenty-four nutritionists participated (four focus groups; average per group: six people); the majority (n = 22) had experience with 7-10-year-old children. Four themes emerged: (i) healthy and unhealthy food indicators; (ii) suggestions for the online instrument; (iii) potential applications; and (iv) challenges for its construction.

CONCLUSIONS

Comments made by nutritionists enabled the construction of an instrument that is able to answer questions related to food consumption in schools and at home.

Longitudinal associations between BMI, waist circumference, and cardiometabolic risk in US youth: monitoring implications

OBJECTIVE

This study examined whether change in body mass index (BMI) or waist circumference (WC) is associated with change in cardiometabolic risk factors and differences between cardiovascular disease specific and diabetes specific risk factors among adolescents. We also sought to examine any differences by gender or baseline body mass status.

DESIGN

The article is a longitudinal analysis of pre- and post-data collected in the HEALTHY trial. Participants were 4,603 ethnically diverse adolescents who provided complete data at 6th and 8th grade assessments.

METHODS

The main outcome measures were percent change in the following cardiometabolic risk factors: fasting triglycerides, systolic and diastolic blood pressure, high density lipoprotein cholesterol, and glucose as well as a clustered metabolic risk score. Main exposures were change in BMI or WC z-score. Models were run stratified by gender; secondary models were additionally stratified by baseline BMI group (normal, overweight, or obese).

RESULTS

Analysis showed that when cardiometabolic risk factors were treated as continuous variables, there was strong evidence (P < 0.001) that change in BMI z-score was associated with change in the majority of the cardiovascular risk factors, except fasting glucose and the combined risk factor score for both boys and girls. There was some evidence that change in WC z-score was associated with some cardiovascular risk factors, but change in WC z-score was consistently associated with changes in fasting glucose.

CONCLUSIONS

In conclusion, routine monitoring of BMI should be continued by health professionals, but additional information on disease risk may be provided by assessing WC.

Feasibility of an obesity intervention for paediatric primary care targeting parenting and children: Helping HAND

BACKGROUND

  The primary care setting offers the opportunity to reach children and parents to encourage healthy lifestyle behaviours, and improve weight status among children.

OBJECTIVE

  Test the feasibility of Helping HAND (Healthy Activity and Nutrition Directions), an obesity intervention for 5- to 8-year-old children in primary care clinics.

METHODS

  A randomized controlled pilot study of Helping HAND, a 6-month intervention, targeted children with body mass index 85-99%tile and their parents. Intervention group attended monthly sessions and self-selected child behaviours and parenting practices to change. Control group received regular paediatric care and was wait-listed for Helping HAND. Session completion, participant satisfaction, child anthropometrics, dietary intake, physical activity, TV viewing and behaviour-specific parenting practices were measured pre and post intervention.

RESULTS

  Forty parent-child dyads enrolled: 82.5% were Hispanic, 80% had a girl and 65% reported income ≤ $30, 000/year. There was 20% attrition from Helping HAND (attended <4/6 sessions). Families self-selected 4.35 (SD 1.75) behaviours to target during the 6-month programme and each of the seven behaviours was selected by 45-80% of the families. There were no between group differences in the child's body mass index z-score, dietary intake or physical activity post intervention. Intervention group viewed 14.9 (SE 2.3) h/week of TV post intervention versus control group 23.3 (SE 2.4) h/week (P < 0.05).

CONCLUSION

  Helping HAND is feasible, due to low attrition, good programme attendance, and clinically relevant improvements in some child and parenting behaviours.

Food Intake Recording Software System, version 4 (FIRSSt4): a self-completed 24-h dietary recall for children

The Food Intake Recording Software System, version 4 (firsst4), is a web-based 24-h dietary recall (24 hdr) self-administered by children based on the Automated Self-Administered 24-h recall (ASA24) (a self-administered 24 hdr for adults). The food choices in firsst4 are abbreviated to include only those reported by children in US national surveys; and detailed food probe questions are simplified to exclude those that children could not be expected to answer (e.g. questions regarding food preparation and added fats). ASA24 and firsst4 incorporate 10 000+ food images, with up to eight images per food, to assist in portion size estimation. We review the formative research conducted during the development of firsst4. When completed, firsst4 will be hosted and maintained for investigator use on the National Cancer Institute's ASA24 website.

How to engage children in self-administered dietary assessment programmes

Effectively assessing children's dietary intake is essential for understanding the complex relationships among dietary behaviours and obesity. Dietary assessment accuracy decreases when children are unable or unmotivated to complete accurate self-reports. Technology-based assessment instruments for children's self-report of diet can be enhanced in light of developments in media psychology and communication science. To motivate children to complete a dietary assessment, researchers could use animated, customisable agents; embed the assessment process into a video game; or add narratives to encourage self-reporting behaviour. To improve accuracy, the intake environment could be recreated virtually; training sessions could be interspersed to improve portion estimation; and implicit attitudinal measures could be incorporated as a control or to increase validity. Research is needed to evaluate possible methods of enhancing children's self-reporting motivation and accuracy. The main challenge remains how to engage children without biasing their reporting.

Relationship of fruit and vegetable intake with adiposity: a systematic review

Fruit and vegetable (FV) intake has been proposed to protect against obesity. The purpose of this paper was to assess the FV consumption to adiposity relationship. Twenty-three publications were included.

INCLUSION CRITERIA

longitudinal or experimental designs; FV intake tested in relation to adiposity; child, adolescent or adult participants; published in English-language peer-reviewed journals.

EXCLUSION CRITERIA

dietary pattern and cross-sectional designs; participants with health concerns. Experimental studies found increased FV consumption (in conjunction with other behaviours) contributed to reduced adiposity among overweight or obese adults, but no association was shown among children. Longitudinal studies among overweight adults found greater F and/or V consumption was associated with slower weight gain, but only half of child longitudinal studies found a significant inverse association. Limitations in methods prevented a thorough examination of the role of increased FV intake alone or mechanisms of effect. An inverse relationship between FV intake and adiposity among overweight adults appears weak; this relationship among children is unclear. Research needs to clarify the nature of, and mechanisms for, the effects of FV consumption on adiposity. Whether increases in FV intake in isolation from lower caloric intake or increased physical activity will result in declines or slower growth in adiposity remains unclear.

Serum levels of the adipokine fasting-induced adipose factor/angiopoietin-like protein 4 depend on renal function

Fasting-induced adipose factor/angiopoietin-like protein 4 (FIAF/Angptl4) was recently introduced as a novel adipokine influencing glucose and lipid homeostasis. In the current study, we quantified circulating FIAF/Angtl4 levels in patients on chronic hemodialysis (CD) as compared to controls with a glomerular filtration rate above 50 ml/min. FIAF/Angptl4 was determined by ELISA in control (n=60) and CD (n=60) patients and correlated to clinical and biochemical measures of renal function, glucose and lipid metabolism, as well as inflammation, in both groups. Median serum FIAF/Angptl4 levels were more than 5-fold higher in CD patients (48.3 μg/l) as compared to control subjects (8.4 μg/l) (p<0.001). Furthermore, serum creatinine independently predicted FIAF/Angptl4 concentrations in multiple regression analyses in control subjects (p<0.01). In CD patients, C-reactive protein was independently and positively associated with circulating FIAF/Angptl4 (p<0.01). Taken together, we show that serum FIAF/Angptl4 levels are significantly increased in end-stage renal disease and independently associated with markers of renal function in control subjects.

Presence of diabetes risk factors in a large U.S. eighth-grade cohort

OBJECTIVE

The study was conducted in 12 middle schools to determine the prevalence of diabetes, pre-diabetes, and diabetes risk factors in eighth-grade students who were predominantly minority and evaluate the feasibility of collecting physical and laboratory data in schools.

RESEARCH DESIGN AND METHODS

Anthropometric measurements and fasting and 2-h post-glucose load blood draws were obtained from approximately 1,740 eighth-grade students.

RESULTS

Mean recruitment rate was 50% per school, 49% had BMI > or = 85th percentile, 40.5% had fasting glucose > or = 100 mg/dl, 0.4% had fasting glucose > or = 126 mg/dl, and 2.0% had 2-h glucose > or = 140 mg/dl and 0.1% > or = 200 mg/dl. Mean fasting insulin value was 30.1 microU/ml, 36.2% had fasting insulin > or = 30 microU/ml, and 2-h mean insulin was 102.1 microU/ml. Fasting and 2-h glucose and insulin values increased across BMI percentiles, and fasting glucose was highest in Hispanic and Native American students.

CONCLUSIONS

There was a high prevalence of risk factors for diabetes, including impaired fasting glucose (> or =100 mg/dl), hyperinsulinism suggestive of insulin resistance (fasting insulin > or = 30 microU/ml), and BMI > or = 85th percentile. These data suggest that middle schools are appropriate targets for population-based efforts to decrease overweight and diabetes risk.

BMI from 3–6 y of age is predicted by TV viewing and physical activity, not diet

OBJECTIVE

To investigate whether, diet, physical activity, sedentary behavior or television (TV) viewing predicted body mass index (BMI) among 3-7-y-old children.

DESIGN

A triethnic cohort of 3-4-y-old children was followed for 3 y from 1986 to 1989.

MEASUREMENTS

BMI was assessed at the beginning and end of each measurement year. Heart rate monitoring and observation were used to assess physical activity. Diet (calories, % calories from fat and carbohydrate), sedentary behavior and TV viewing were assessed by direct observation in each year. A repeated measures regression analysis with year as a factor and BMI at the end of each year as dependent variables was run. Nonsignificant variables were removed in a stepwise backward deletion process and significant interactions graphed.

RESULTS

The interactions between minutes of TV viewing per hour and study year and minutes of physical activity per hour and study year were significant (P<0.05). There were also significant main effects for TV viewing, physical activity and BMI from the beginning of the study. The model accounted for 65% of the variance in BMI across the three study years. Plotting the significant interactions demonstrated that physical activity was positively associated with BMI in year 1, and negatively associated in years 2 and 3 with a stronger negative relationship in year 3 than 2. TV viewing became positively associated with BMI during the third study year.

CONCLUSION

Physical activity and TV viewing were the only significant predictors (other than baseline BMI) of BMI among a triethnic cohort of 3-4-y-old children followed for 3 y with both physical activity (negatively associated) and TV viewing (positively associated) becoming stronger predictors as the children aged. It appears that 6 or 7 y is a critical age when TV viewing and physical activity may affect BMI. Therefore, focusing on reducing time spent watching television and increasing time spent in physical activity may be successful means of preventing obesity among this age group.

Eating patterns, dietary quality and obesity

Obesity among children has reached epidemic proportions. Today, an estimated one in four children in the United States is overweight. while 11% arc obese. Children who are overweight tend to remain so up to 20 years of age; in general, they have a 1.5- to twofold higher risk for becoming overweight as adults. The prevalence of overweight has increased approximately twofold in the 20-year period from 1974 to 1994, with the largest increases observed among 19- to 24-year-olds. The annual increases in weight and obesity that occurred from 1983 to 1994 were 50% higher than those from 1973 to 1982. Overweight youth are 2.4 times as likely to have a high serum total cholesterol level, and 43.5 times as likely to have three cardiovascular risk factors. Although the total energy intake of children has remained the same, and the macronutrient density of the diet has changed, the percentage of energy from fat has decreased, while that from carbohydrates and protein has increased. Children have been consuming lower amounts of fats/oils, vegetables/soups, breads/grains, mixed meats, desserts, candy, and eggs. and increasing amounts of fruits/fruit juices, beverages. poultry, snacks, condiments, and cheese. Changes in specific eating patterns may explain the increase in adiposity among children; e.g., increases have occurred in the number of meals eaten at restaurants, food availability, portion sizes, snacking and meal-skipping. Successful prevention and treatment of obesity in childhood could reduce the adult incidence of cardiovascular disease. Because substantial weight loss is difficult to maintain, the prevention of obesity by promoting healthier lifestyles should be one of our highest priorities in the new millennium.

A motivational interviewing intervention to increase fruit and vegetable intake through Black churches: results of the Eat for Life trial

OBJECTIVES

This study reports on Eat for Life, a multicomponent intervention to increase fruit and vegetable consumption among African Americans that was delivered through Black churches.

METHODS

Fourteen churches were randomly assigned to 3 treatment conditions: (1) comparison, (2) self-help intervention with 1 telephone cue call, and (3) self-help with 1 cue call and 3 counseling calls. The telephone counseling in group 3 was based on motivational interviewing. The primary outcome, assessed at baseline and 1-year follow-up, was fruit and vegetable intake as assessed by 3 food frequency questionnaires.

RESULTS

Change in fruit and vegetable intake was significantly greater in the motivational interviewing group than in the comparison and self-help groups. The net difference between the motivational interviewing and comparison groups was 1.38, 1.03, and 1.21 servings of fruits and vegetables per day for the 2-item, 7-item, and 36-item food frequency questionnaires, respectively. The net difference between the motivational interviewing and self-help groups was 1.14, 1.10, and 0.97 servings for the 2-item, 7-item, and 36-item food frequency questionnaires, respectively.

CONCLUSIONS

Motivational interviewing appears to be a promising strategy for modifying dietary behavior, and Black churches are an excellent setting to implement and evaluate health promotion programs.

Family and child-care provider influences on preschool children's fruit, juice, and vegetable consumption

Children's intakes of fruit, juice, and vegetables (FJV) do not meet the recommended minimum of five daily servings, placing them at increased risk for development of cancer and other diseases. Because children's food preferences and practices are initiated early in life (e.g., 2-5 years of age), early dietary intervention programs may have immediate nutritional benefit, as well as reduce chronic disease risk when learned healthful habits and preferences are carried into adulthood. Families and child-care settings are important social environments within which food-related behaviors among young children are developed. FJV preferences, the primary predictor of FJV consumption in children, are influenced by availability, variety, and repeated exposure. Caregivers (parents and child-care providers) can influence children's eating practices by controlling availability and accessibility of foods, meal structure, food modeling, food socialization practices, and food-related parenting style. Much remains to be learned about how these influences and practices affect the development of FJV preferences and consumption early in life.

A 7-item versus 31-item food frequency questionnaire for measuring fruit, juice, and vegetable intake among a predominantly African-American population

OBJECTIVE

This study sought to determine which of 2 fruit and vegetable food frequency questionnaires (FFQs) most closely approximated intake measured by the average of four 24-hour dietary recalls.

DESIGN

Participants completed either a 31-item FFQ (n = 70) or 7-item FFQ (n = 76) on 2 occasions approximately 2 weeks apart. During the interval between FFQs1 participants provided four 24-hour dietary recalls via telephone interview.

SUBJECTS/SETTING

Participants were 146 persons with food preparation responsibilities in families of students in grades 3 through 5. Respondents were predominantly African-American women in Atlanta, Ga.

STATISTICAL ANALYSIS

Pearson correlation coefficients of log-transformed values estimated the reliability of each FFQ and compared FFQ estimates to reference values. The intraclass correlation coefficient evaluated consistency across 24-hour recalls.

RESULTS

The first FFQs overestimated intake approximately twofold. The 31-item FFQ estimates exceeded 7-item FFQ estimates by approximately 30% . Correlations with recall estimates were high for the 7-item FFQ and moderate to low for the 31-item FFQ. The second FFQ estimates were more highly correlated to reference values. From the first to the second administration, 7-item FFQ estimates dropped from 5.2 to 2.7 servings, and 31-item FFQ estimates dropped from 6.7 to 3.5 servings. Neither FFQ produced highly reliable estimates.

CONCLUSIONS

Mean total fruit and vegetable consumption was closer to reference estimates for the first 7-item FFQ and the second 31-item FFQ. The 7-item FFQ correlated more highly with reference estimates than did the 31-item FFQ. Therefore, we conclude that for African-American adults, a 1-time-administered FFQ using 7 broad food categories correlates more highly with reference values than a FFQ using 31 individual fruit and vegetable items.

Ecological and socioeconomic correlates of fruit, juice, and vegetable consumption among African-American boys

BACKGROUND

Investigators have reported that the availability of foods in local grocery stores correlated with consumption when using large geopolitical units of analysis, e.g., zip codes. Associations across smaller geopolitical units, e.g., census tracts, have not been tested, nor has this work focused on restaurant availability, child consumption, or specific ethnic groups.

METHODS

This study examined whether median family income and fruit, juice, and vegetable (FJV) availability in grocery stores, restaurants, and homes in 11 census tracts correlated with FJV consumption among 11- to 14-year-old African-American Boy Scouts. FJV consumption was measured in 90 scouts using two 24-h food recalls. Instruments were developed to measure the availability of FJV at area grocery stores, restaurants, and homes where troop members resided.

RESULTS

Median household income (from 1990 census) was significantly correlated with restaurant fruit availability. Significant correlations were found between restaurant juice and vegetable availability and Boy Scout reported consumption of juice and vegetables.

CONCLUSION

Census tract may be a useful unit when studying restaurant, but not grocery store, FJV availability. Within a census tract, restaurant FJV availability may be a significant target for community intervention and process evaluation.

Using goal setting as a strategy for dietary behavior change

Recent reviews have noted that behavioral theory-based nutrition education programs are more successful at achieving food behavior change than knowledge-based programs and that a clear understanding of the mechanisms of behavior change procedures enable dietetics professionals to more effectively promote change. Successful dietary behavior change programs target 1 or more of the personal, behavioral, or environmental factors that influence the behavior of interest and apply theory-based strategies to influence or change those factors. Goal setting is a strategy that is frequently used to help people change. A 4-step goal-setting process has been identified: recognizing a need for change; establishing a goal; adopting a goal-directed activity and self-monitoring it; and self-rewarding goal attainment. The applications of goal setting in dietary interventions for adults and children are reviewed here. Because interventions using goal setting appear to promote dietary change, dietitians should consider incorporating the goal-setting strategies to enhance the behavior change process in nutrition education programs.

Child-reported family and peer influences on fruit, juice and vegetable consumption: reliability and validity of measures

Family, peers and other environmental factors are likely to influence children's dietary behavior but few measures of these phenomena exist. Questionnaires to measure family and peer influences on children's fruit, juice and vegetable (FJV) consumption were developed and pilot tested with an ethnically diverse group of Grade 4-6 children. Principal components analyses revealed subscales with acceptable internal consistencies that measured parent and peer FJV modeling, normative beliefs, normative expectations, perceived peer FJV norms, supportive and permissive parenting practices, food rules, permissive eating, and child food preparation. Internal consistencies were adequate to high, but test-re-test correlations often were low. Children also completed questionnaires on FJV availability and accessibility in the home, and food records for 2 days in the classroom. Parental modeling, peer normative beliefs and FV availability were significantly correlated with FJV consumption. Further research with these scales is warranted.

Risk factor distribution among sociodemographically diverse African American adults

Because African Americans tend to have lower socioeconomic status (SES) than whites and numerous health indicators are related to SES variables, it is important when examining between-group differences in health indices to account for SES differences. This study examined the effects of income and education on several biologic and behavioral risk factors in a sample of sociodemographically diverse African American adults. Approximately 1,000 African American adults (aged 18-87) were recruited from 14 churches with predominantly black membership to participate in a nutrition education intervention. Demographics, height, weight, blood pressure, self-reported cigarette and alcohol use, self-reported diet by food frequency questionnaire, serum carotenoids, serum total cholesterol, and nutrition knowledge were assessed. The association of these risk factors were examined by four levels of education and income. For men, body mass index, blood pressure, total cholesterol, daily intake of fruits and vegetables, serum carotenoids, heavy alcohol use, or exercise were not associated significantly with income or education using analysis of variance (ANOVA). Past month alcohol use and nutrition knowledge were associated positively with education, but not income. For women, body mass index and smoking were associated inversely with income, but not with education. Blood pressure, total cholesterol, intake of fruits and vegetables, heavy alcohol use, and exercise were not associated with either income or education using ANOVA. Serum carotenoids, any 30-day alcohol use, and nutrition knowledge were associated positively with both income and education. Results using linear regression generally were similar for men and women, although a few more variables were associated significantly with SES compared to ANOVA analyses. Several health indicators that have been associated with socioeconomic variables in whites were not associated or only weakly associated in this diverse sample of African Americans. One interpretation of these findings is that SES factors may function differently among blacks and whites.

Effect of a la carte and snack bar foods at school on children's lunchtime intake of fruits and vegetables

OBJECTIVES

To compare lunch fruit, juice, and vegetable (FJV) intake of fourth-grade students who receive only National School Lunch Program meals and fifth-grade students who also have access to a school snack bar and to compare FJV intake by meal source among fifth-grade students.

DESIGN

Cross-sectional study: students completed FJV preference questionnaires and 5 days of lunch food records in classrooms.

SUBJECTS/SETTING

312 fourth- and 282 fifth-grade students in south Texas.

MAIN OUTCOME MEASURES

Mean FJV consumption.

STATISTICAL ANALYSES PERFORMED

Descriptive statistics, correlation analyses, analysis of variance, analysis of covariance.

RESULTS

Fourth-grade students (n = 312) consumed significantly more fruits, juices, and vegetables (0.80 serving) than fifth-grade students (n = 282) (0.60 serving). Students whose parents reported a high school education or less consumed more regular and total vegetables than students whose parents reported some college or higher education. There were no interaction effects among gender, grade, ethnic, or family education groups. Fifth-grade students who ate only snack bar meals consumed significantly less total fruits, juices, and vegetables (0.40 serving) than fifth-grade students who ate school lunch meals (0.82 serving). Controlling for FJV preferences did not change the main effect for grade level in the FJV consumption models.

APPLICATIONS/CONCLUSIONS

FJV consumption during school lunch is low. School foodservice staff should identify FJV items that middle school students prefer and increase availability of those items in middle school cafeterias and snack bars.

Validation of three food frequency questionnaires and 24-hour recalls with serum carotenoid levels in a sample of African-American adults

The validity of self-reported fruit and vegetable intake in minority populations has not been adequately established. In this study, the authors examined the association of three food frequency questionnaires (FFQs) and 24-hour dietary recalls with serum carotenoid levels. Approximately 1,000 African-American adults recruited from 15 churches in Atlanta, Georgia (1997-1998) completed three fruit and vegetable FFQs: a seven-item instrument assessing intake during the past month; a two-item measure assessing usual intake; and a 36-item measure adapted from the Health Habits and History Questionnaire. A total of 414 participants received a 24-hour recall by telephone, and 105 of them received two additional recalls. Serum levels of lycopene, lutein, cryptoxanthin, alpha-carotene, and beta-carotene were assessed in 813 participants and used as the validity criterion. The correlations of fruit and vegetable servings with specific and total serum carotenoid levels were generally higher for the 36-item FFQ than for the two-item and seven-item instruments. The strongest correlation of fruit and vegetable servings with total carotenoid levels was observed for the three recalls (r = 0.42), with the 36-item FFQ and the single 24-hour recall yielding comparable correlations (r = 0.35 and r = 0.37, respectively). The validity of the 36-item fruit and vegetable FFQ was generally as strong as the validity of both 1 and 3 days of recalls. Given the lower cost and time needed for administration relative to recalls, it appears that the 36-item FFQ has merit for evaluating fruit and vegetable health interventions.

Social-environmental influences on children's diets: results from focus groups with African-, Euro- and Mexican-American children and their parents

Children's fruit, juice and vegetable (FJV) and fat intakes do not meet recommended guidelines. Since personal factors account for only a small percentage of the variability in children's FJV consumption, social and environmental influences were explored via focus group discussions with Grade 4-6 African-, Euro- and Mexican-American students and parents. Questions included the effects of social influences, availability and accessibility on children's FJV and low-fat food choices. Few ethnic differences were noted. A variety of low-fat items and fresh FJV (not cut-up) were available at home; older children were expected to prepare their own. Eating out occurred at least twice a week; FJV were not usual restaurant choices. Students reported some modeling by parents (more mothers) and friends (usually at lunch). Negative peer responses for eating vegetables were reported. Parents were concerned with children eating too much junk food and not enough FJV, recognized the outside influences their children received about food, and reported several methods to encourage children to eat FJV. Recommendations for future interventions are proposed.

GO GIRLS!: results from a nutrition and physical activity program for low-income, overweight African American adolescent females

This article describes the development, implementation, and results of an intervention designed for inner-city, overweight African American adolescent women. Fifty-seven participants were recruited from four public housing developments. Participants were administered physiologic, dietary, and cognitive assessments at baseline and immediately postintervention. Each session comprised three elements: (1) an educational/behavioral activity, (2) 30 to 60 minutes of physical activity, and (3) preparation and tasting of low-fat meals. In the absence of a control group, results were compared for high and low attenders, the former defined as attending at least 50% of the sessions. High attenders (n = 26) showed more favorable 6-month posttest values for most outcomes compared with low attenders (n = 31). These effects achieved statistical significance for nutrition knowledge, low-fat practices, perceived changes in low-fat practices, and social support.

Socioenvironmental influences on children's fruit, juice and vegetable consumption as reported by parents: reliability and validity of measures

OBJECTIVE

To pilot test theory-based questionnaires to measure socioenvironmental influences on children's fruit, juice and vegetable (FJV) consumption as reported by parents.

DESIGN

Cross-sectional.

SETTING

Parents of fourth to sixth grade students completed socioenvironmental questionnaires. The students completed food records (FRs) for 2 days in the classroom.

SUBJECTS

Interviews were completed by 109 parents (17% African-American, 32% Hispanic-American and 51 Euro-American).

RESULTS

Student mean daily FJV intake was 2.1 servings. Principal components analyses revealed subscales measuring positive and negative parenting practices; self-efficacy for modelling and planning/encouraging FJV consumption, and making FJV available; encouraging, consequences and discouraging food socialization practices; negative home, cost and canned/frozen food barriers; meal planning; child shopping; mother food preparation; and child lunch and dinner FJV preparation practices. Internal consistencies were adequate to high. Negative parent practices and negative home FJV barriers were significantly negatively correlated with child FJV consumption variables. Planning/encouraging self-efficacy was positively associated with fruit consumption, and child dinner FJV preparation was significantly negatively correlated with child juice consumption.

CONCLUSIONS

These questionnaires may provide important insights about the relationship between parent-reported socioenvironmental influences and children's FJV consumption. Future work should test these questionnaires with larger groups of parents and youths, with more reliable estimates of usual FJV intake, e.g. 7-day food records, to obtain a detailed understanding of how parents influence what children eat. Tests of models of relationships among these variables are warranted, but should control for possible confounding variables, e.g. socioeconomic status, gender of the child, etc.

Process evaluations of the 5-a-day projects

Process evaluation is an important, but infrequently conducted, component of evaluating the impact of health promotion interventions. The process evaluation results from the nine 5-a-Day projects were overviewed. Process evaluation helped explain some of the weaker aspects of program performance, process indicators occasionally declined over time and varied by demographic characteristics, and some process measures were related to mediating variables and program outcomes. Future development of process evaluation must include further development of concepts, more consistent and thorough conduct of process evaluation, appropriate methodological work, and assessment of the relations among the process evaluation components and the program mediators and outcomes. Further development in this area promises refinement in understanding how and why interventions achieve their effects, how best to conduct intervention programs to maximize effects, and enhancement of the internal and external validity of the studies.

Gimme 5 fruit and vegetables for fun and health: process evaluation

Gimme 5 (Georgia) was a school-based nutrition education effectiveness trial to help fourth- and fifth-grade students eat more fruit, 100% juice, and vegetables (FJV). Process evaluation assessed fidelity of implementation, reach, and use of intervention materials and environmental mediators: teacher training, curriculum delivery, participation in family activities, attendance at evening point-of-purchase grocery store activities, and availability and accessibility of FJV at home. Approximately half of the curriculum activities were implemented in fourth and fifth grades. The lowest proportion completed were those most pertinent to behavior change. Eighty-seven percent of parents reported participating in homework activities with their fourth grader, 66% with fifth graders. Sixty-five percent of parents reported viewing a video with their child in both grades. Ten percent attended evening point-of-purchase grocery store activities. The low level of implementation and modest level of participation in family activities suggest that higher levels of behavior change may have occurred if exposure to the intervention had been higher.

Gimme 5 fruit, juice, and vegetables for fun and health: outcome evaluation

A theory-based multicomponent intervention (Gimme 5) was designed and implemented to impact fourth- and fifth-grade children's fruit, juice, and vegetable (FJV) consumption and related psychosocial variables. Gimme 5 was a randomized controlled intervention trial with school (n = 16 elementary) as unit of random assignment and analysis. Participants included the cohort of students who were in the third grade in the winter of 1994 and students who joined them in the fourth and fifth grades. The intervention included a curriculum, newsletters, videotapes, and point-of-purchase education. Evaluation included 7-day food records and psychosocial measures from students, telephone interviews with parents, and observational assessments. Favorable results were observed for consumption of FJV combined, FJV consumed at weekday lunch, eating FJV self-efficacy, social norms, asking behaviors, and knowledge. A theory-based school nutrition education program can help change children's FJV consumption and impact factors at home that predispose to FJV consumption, but changes were small, and their persistence is unknown.

Dietary change through African American churches: baseline results and program description of the eat for life trial

BACKGROUND

Eat for Life, a multicomponent intervention to increase fruit and vegetable (F & V) consumption among African Americans, is delivered through African American churches.

METHODS

Fourteen churches were randomly assigned to one of three treatment conditions: 1) comparison; 2) culturally-sensitive multicomponent intervention with one phone call; and 3) culturally-sensitive multicomponent intervention with four phone calls. The intervention included an 18-minute video, a project cookbook, printed health education materials, and several "cues" imprinted with the project logo and a 5 A Day message. A key element of the telephone intervention was the use of motivational interviewing, a counseling technique originally developed for addictive behaviors. Major outcomes for the trial included total F & V intake, assessed by food-frequency questionnaires (FFQs) and 24-hour recalls, and serum carotenoids. Psychosocial variables assessed included outcome expectations, barriers to F & V intake, preference for meat meals, neophobia, social support to eat more F & V, self-efficacy to eat more F & V, and nutrition knowledge.

RESULTS

Baseline mean F & V intakes across the three FFQs ranged from 3.45 to 4.28 servings per day. Intake based on a single 24-hour recall was 3.0 servings. Variables positively correlated with F & V intake included self-efficacy, outcome expectations, and a belief that F & V contain vitamins. Factors negatively correlated with intake include perceived barriers, meat preference, neophobia, and high-fat cooking practices. The completion rate for the first telephone counseling call was 90%. Completion rates for the remaining three calls ranged from 79% to 86%.

CONCLUSION

The recruitment and intervention methods of the Eat for Life study appear promising. The telephone intervention based on motivational interviewing is potentially useful for delivering dietary counseling.

Influence of school organizational characteristics on the outcomes of a school health promotion program

Researchers assessed the possible moderating effects of school organizational characteristics (school climate, school health, and job satisfaction) on outcomes of a teacher health behavior change program. Thirty-two public schools were matched and randomly assigned either to treatment or control conditions. Organizational, dietary, and physiologic data were collected from third to fifth grade teachers over three years. Treatment schools received a teacher wellness program for two years. Psychometrics of most organizational scales achieved acceptable levels of reliability. Mixed model analyses were conducted to test for moderating effects. Treatment schools with high organizational climate and health scores reported higher fruit and juice and vegetable consumption at Year 2 compared with intervention schools with low scores. Treatment schools with high job satisfaction scores reported higher fruit and juice and lower-fat food consumption at Year 3 compared with intervention schools with low scores. These measures may be used as a tool to assess the environment in which school health promotion programs are presented. Future interventions may need to be tailored to the organizational characteristics of schools.

Intraindividual variability and reliability in a 7-day exercise record

PURPOSE

High levels of day-to-day or intraindividual variability implies unreliability of a measure of physical activity. Unreliability in a measure leads to attenuation of correlations with other variables. As intraindividual variability increases, the number of days necessary to assess physical activity to achieve the desired level of reliability increases. The use of an intraclass correlation to assess day-to-day reliability in a measure assumes compound symmetry.

METHODS

This study reports on these issues in a sample of 165 elementary school teachers who maintained a 7-d record of physical activity each year for 3 yr. Analyses were conduced with physical activity measured as minutes, MET minutes, and kcal. Analyses were conducted with PROC MIXED in SAS controlling for the clustering effect by school.

RESULTS

Compound symmetry could not be supported across 7 d of the record. The weekdays tended to intercorrelate, Saturday correlated at very low levels, and Sunday correlated with Monday only. Compound symmetry was supported across the three weeks.

CONCLUSIONS

To achieve a reliability of 0.8 using a 7-d activity record requires 2 wk of assessment. The reliability of measures of physical activity require more careful attention, and likely require more points of assessment to achieve desired levels.

Pilot study of the validity and reliability of brief fruit, juice and vegetable screeners among inner city African-American boys and 17 to 20 year old adults

OBJECTIVE

Compare the validity and reliability of a one-week fruit, juice and vegetable (FJV) food frequency questionnaire (FFQ) that does not require averaging in response categories and one-week food recognition form (FRF) against three to four 24-hour dietary recalls (24hdr) among mostly African-American boys and 17 to 20 year-old adults for possible use in subsequent intervention studies.

DESIGN

In Study One, the FFQ was administered to 40 boys in four Boy Scout (BS) troops on two occasions separated by two weeks. The FRF was administered to 36 boys in four other BS troops after school on six school days, covering seven consecutive days. All these boys completed four 24hdr, including one Sunday. In Study Two, 56 17 to 20 year-old adults completed the FFQ during telephone interviews on two occasions two weeks apart. In between, they completed three 24hdr by telephone interview on one weekend and two weekdays.

SUBJECTS/SETTING

Participants in Study One were members of eight urban BS troops, and in Study Two were high school (HS) seniors and recent HS graduates. BS data were collected at times scheduled for troop meetings or immediately after school. The young adult group completed telephone interviews in the evenings and on weekends.

MAIN MEASURES

This research compared a FJV FFQ and a FJV FRF (incorporating the same 24 foods) against three to four 24hdr conducted using NDS software from the University of Minnesota.

STATISTICAL ANALYSES PERFORMED

Descriptive statistics, intraclass correlations, Spearman correlations, corrections for attenuation.

RESULTS

The first FFQ provided substantially higher mean consumption estimates for both groups. The FFQ had moderate reliability across assessments and moderate validity coefficients for fruit and total FJV combined for the BS sample. The FRF had higher validity coefficients for juice. The FFQ had moderate reliability and poor validity among the young adult group. Correction for measurement error in the 24hdr substantially increased validity coefficients to high levels for BS fruit and total FJV and to moderate levels for the HS groups, with some exceptions.

APPLICATIONS/CONCLUSIONS

FFQ more validly assessed fruit and combined FJV consumption for the nine to 14 year-old BS but overestimated mean values. FRF means were closer to those of the 24hdr and were more valid for assessing juice consumption. The FFQ had moderate validity among the young adult group but overestimated consumption. Further research is needed on simpler methods of reporting diet in these age groups.

Psychosocial correlates of dietary intake: advancing dietary intervention

Psychosocial variables that predict dietary behavior become important targets for change in nutrition education programs. Psychosocial variables in models with higher predictability provide more effective levers to promote healthy dietary change. A review of the literature on models with psychosocial variables predicting dietary fat and fruit and vegetable consumption revealed generally low predictiveness, R2 < 0.3 (where R2 is the squared multiple correlation of the statistical model). No single theory provided models that regularly out-predicted others. When models predicted narrower categories of behavior (e.g. milk or salad consumption), predictiveness tended to be higher. Substantial problems were revealed in the psychometrics of both the independent and dependent variables. Little theory-based research has been conducted with adolescents, and the few studies done with children had low predictiveness. In order to increase the predictiveness of models, future research should combine variables from several theories, attend to the psychometrics of all variables, and incorporate variables that moderate the relationship of psychosocial to dietary behavior (e.g. genetics of taste, stage in the life course). Refinements on current research would include longitudinal designs and use of non-self-report methods of dietary behavior to supplement the self-report methods. Improved understanding of dietary behavior should lead to more effective dietary behavior change interventions.

Factors related to adiposity among children aged 3 to 7 years

OBJECTIVE

To compare diet and physical activity between a group of children aged 4 to 7 years who had increased their sum of 7 skinfolds by 1.5 standard deviations or more since the previous year and those who had not.

SUBJECTS/DESIGN

A longitudinal design was used wherein children had their body composition assessed at 4 annual intervals. Fifteen study subjects were identified from a larger study on the development of cardiovascular risk factors in children. Three matched control subjects were identified for all but 4 study subjects. Children were included if they were 3 or 4 years old at the time of the first of 4 annual clinics to collect data. Children were volunteers from a mid-sized city.

MEASURES

Seven skinfold sites were assessed, each 3 times. An average was taken of the mean at each site. Diet and physical activity were assessed using observational methods for up to 4 days for each of 3 years between the 4 annual clinics (held in the summers of 1986, 1987, 1988, and 1989).

RESULTS

Children consumed significantly (P = .02) more fat grams and suggestively higher percentages of energy from fat (P = .06), total energy (P = .08), and percentage energy from protein (P = .10). No differences were detected for percent energy from carbohydrate, physical activity, or height.

CONCLUSIONS

Programs to prevent childhood obesity might have success by targeting dietary fat consumption among children as young as 4 years old, but further research is needed.

Gender differences in chronic disease risk behaviors through the transition out of high school

BACKGROUND

Major life transitions (e.g., graduation from high school) are times when many changes occur in a person's social and physical environment. Men and women likely experience aspects of these changes differently. As a result, health-related behaviors likely change at these times with possible differences in these changes by gender.

METHODS

Gender differences in the performance of chronic disease risk-related behaviors (fruit, juice, and vegetable intake; physical activity; tobacco and alcohol use; and sexual practices) through the transition out of high school (HS) were assessed in a secondary analysis of a nationally representative sample from the 1992 National Health Interview Survey-Youth Risk Behavior Survey. The survey was completed by 5881 young people aged 14 to 21 years. Regression discontinuity analysis with piecewise regression was performed.

RESULTS

Statistically significant gender by transition effects were obtained for exercise/physical activity (decreases at the transition point for males), snuff use (decrease for females in HS), binge drinking and number of days drinking alcohol (increases for males at the transition point), and use of alcohol or drugs before sexual intercourse (decrease for females post HS). Fruit intake decreased for males and females and daily and heavy cigarette smoking increased during the HS years. Effect sizes were small but promising, given that the data set was not designed to test this hypothesis.

CONCLUSION

These data offer evidence of differences by gender in chronic disease risk behaviors through the HS transition. Longitudinal studies are needed to assess the true nature of these differences, the tracking of these risk behaviors and their personal, social, and environmental determinants, including gender-specific determinants, that may explain these changes and inform future intervention development.

Ethnic differences in cancer risk behaviors through the transition out of high school

Differences were assessed by ethnic group in the performance of cancer risk related lifestyle behaviors through the transition out of high school. Data were obtained from a nationally representative probability sample survey, the 1992 National Health Interview Survey-Youth Risk Behavior Survey. A cross-sectional sub-sample included adolescents with an age range from high school freshmen to young adults within four years after high school. Self reported indicators of diet, physical activity, cigarette smoking, smokeless tobacco use, alcohol use, and sexual practices were the primary dependent measures. Cancer risk increased at the transition out of high school through changes in cancer related behaviors. Hispanic-American males experienced somewhat higher risks after the transition for chewing tobacco and snuff. African Americans experienced somewhat higher risks after the transition for physical activity, chewing tobacco, and number of sexual partners. Further research needs to verify these findings with longitudinal designs, assessment of tracking of behaviors through the transition, and of the ecological, social and psychosocial correlates that may explain why these changes occurred.