Intervention-related bias in reporting of food intake by fifth-grade children participating in an obesity prevention study.

Data collected as part of Pathways, a school-based trial for the primary prevention of obesity in American Indian children conducted between 1997 and 2000, were analyzed to examine possible intervention-related bias in food reporting. The authors hypothesized that children in the intervention schools may have systematically underreported their dietary intake relative to children in the control schools. Nutrient intake estimates for lunch derived from record-assisted 24-hour dietary recalls were compared with intake estimates from observed lunch intakes. Reported nutrient intakes were included in regression analyses as the dependent variables; observed intake, intervention condition, and age were included as independent variables. Results indicated that, among females, intervention condition was a significant predictor of reported energy, fat, and saturated fatty acid intakes. Independently of observed intake, reported lunch energy intake among females in the intervention schools was 66.8 calories lower than reported intake among females in the control schools (p = 0.03). These findings suggest that investigators should consider bias in reporting of dietary intake by intervention condition when conducting diet-focused intervention studies. Specifically, enhancing measures that rely on self-reports with objective measures of dietary intake would help investigators to evaluate whether differential reporting by treatment group has occurred.

Pathways: a school-based, randomized controlled trial for the prevention of obesity in American Indian schoolchildren.

BACKGROUND: Childhood obesity is a major public health problem in the United States, particularly among American Indian communities. OBJECTIVE: The objective was to evaluate the effectiveness of a school-based, multicomponent intervention for reducing percentage body fat in American Indian schoolchildren. DESIGN: This study was a randomized, controlled, school-based trial involving 1704 children in 41 schools and was conducted over 3 consecutive years, from 3rd to 5th grades, in schools serving American Indian communities in Arizona, New Mexico, and South Dakota. The intervention had 4 components: 1) change in dietary intake, 2) increase in physical activity, 3) a classroom curriculum focused on healthy eating and lifestyle, and 4) a family-involvement program. The main outcome was percentage body fat; other outcomes included dietary intake, physical activity, and knowledge, attitudes, and behaviors. RESULTS: The intervention resulted in no significant reduction in percentage body fat. However, a significant reduction in the percentage of energy from fat was observed in the intervention schools. Total energy intake (by 24-h dietary recall) was significantly reduced in the intervention schools but energy intake (by direct observation) was not. Motion sensor data showed similar activity levels in both the intervention and control schools. Several components of knowledge, attitudes, and behaviors were also positively and significantly changed by the intervention. CONCLUSIONS: These results document the feasibility of implementing a multicomponent program for obesity prevention in elementary schools serving American Indian communities. The program produced significant positive changes in fat intake and in food- and health-related knowledge and behaviors. More intense or longer interventions may be needed to significantly reduce adiposity in this population.

Pathways curriculum and family interventions to promote healthful eating and physical activity in American Indian schoolchildren.

BACKGROUND: Pathways, a multisite school-based study aimed at promoting healthful eating and increasing physical activity, was a randomized field trial including 1704 American Indian third to fifth grade students from 41 schools (21 intervention, 20 controls) in seven American Indian communities. METHODS: The intervention schools received four integrated components: a classroom curriculum, food service, physical activity, and family modules. The curriculum and family components were based on Social Learning Theory, American Indian concepts, and results from formative research. Process evaluation data were collected from teachers (n=235), students (n=585), and families. Knowledge, Attitudes, and Behavior Questionnaire data were collected from 1150 students including both intervention and controls. RESULTS: There were significant increases in knowledge and cultural identity in children in intervention compared to control schools with a significant retention of knowledge over the 3 years, based on the results of repeating the third and fourth grade test items in the fifth grade. Family members participated in Family Events and take-home activities, with fewer participating each year. CONCLUSION: A culturally appropriate school intervention can promote positive changes in knowledge, cultural identity, and self-reported healthful eating and physical activity in American Indian children and environmental change in school food service.

Design, implementation, and quality control in the Pathways American-Indian multicenter trial.

BACKGROUND: Pathways was the first multicenter American-Indian school-based study to test the effectiveness of an obesity prevention program promoting healthy eating and physical activity. METHODS: Pathways employed a nested cohort design in which 41 schools were randomized to intervention or control conditions and students within these schools were followed as a cohort (1,704 third graders at baseline). The study's primary endpoint was percent body fat. Secondary endpoints were levels of fat in school lunches; time spent in physical activity; and knowledge, attitudes, and behaviors regarding diet and exercise. Quality control (QC) included design of data management systems which provided standardization and quality assurance of data collection and processing. Data QC procedures at study centers included manuals of operation, training and certification, and monitoring of performance. Process evaluation was conducted to monitor dose and fidelity of the interventions. Registration and tracking systems were used for students and schools. RESULTS: No difference in mean percent body fat at fifth grade was found between the intervention and control schools. Percent of calories from fat and saturated fat in school lunches was significantly reduced in the intervention schools as was total energy intake from 24-hour recalls. Significant increases in self-reported physical activity levels and knowledge of healthy behaviors were found for the intervention school students. CONCLUSIONS: The Pathways study results provide evidence demonstrating the role schools can play in public health promotion. Its study design and QC systems and procedures provide useful models for other similar school based multi- or single-site studies.

Pathways: lessons learned and future directions for school-based interventions among American Indians.

BACKGROUND: Pathways, a multicenter study to test the effect of a school-based program to prevent obesity in American Indian children, yielded many benefits and encountered many challenges. This paper explores what we have learned from this study and examines possible future directions. METHODS: Information presented in this paper is based on formative research, study results, and discussions with staff and investigators. RESULTS: Some of the lessons learned relate to having a strong relationship with the tribes, how best to engage the communities, the importance of formative research and achieving standardization in culturally diverse settings, how to incorporate cultural information into curricula, and the importance of family involvement. One of the strengths of the study was the collaborative process that teamed American Indian and non-American Indian investigators and staff. Researchers recognized that they must work in cooperation with research participants including their schools and communities to address challenges, to ensure accurate findings and analyses, and to share benefits. CONCLUSIONS: The lessons learned from Pathways offer valuable insights for researchers into successful approaches to the challenges inherent in research in American Indian communities, particularly in schools, and how to maximize the benefits of such a study.