Application of Path Analysis and Structural Equation Modeling in Nutrition and Dietetics.

This is one of a series of monographs on research design and analysis. The purpose of this article is to describe a set of statistical procedures or techniques used to develop and test structural models that characterize the relationships and interrelationships between a group of concepts and variables. These procedures include multiple regression, exploratory and confirmatory factor analysis, path analysis, and structural equation modeling.

A Randomized Controlled Trial Measuring Effects of Extra Supplemental Nutrition Assistance Program (SNAP) Benefits on Child Food Security in Low-Income Families in Rural Kentucky.

Background: To reduce childhood hunger, the US Department of Agriculture funded several innovative demonstration projects, including the Kentucky Ticket to Healthy Food project.

Objective: The study tested the hypothesis that Ticket to Healthy Food would reduce child food insecurity (FI-C) among rural, low-income households.

Design: The study used a randomized controlled trial in which households were randomly assigned to treatment and control groups.

A Cluster Randomized Controlled Trial of a Home-Delivered Food Box on Food Security in Chickasaw Nation.

Background: The 2010 Child Nutrition reauthorization called for the independent evaluation of innovative strategies to reduce the risk of childhood hunger or improve the food security status of households with children.

Objective: The research question was whether the Packed Promise intervention reduces child food insecurity (FI-C) among low-income households with children.

Design: This study was a cluster randomized controlled trial of 40 school districts and 4,750 eligible, consented households within treatment and control schools.

Measuring the Effects of a Demonstration to Reduce Childhood Food Insecurity: A Randomized Controlled Trial of the Nevada Healthy, Hunger Free Kids Project.

Background: To reduce childhood hunger, the US Department of Agriculture funded a set of demonstration projects, including the Nevada Healthy, Hunger-Free Kids (HHFK) project.

Objective: The study objective was to test whether the Nevada HHFK project reduced child food insecurity (FI-C) among low-income households with young children.

Design: Households were randomly assigned to treatment and control groups, with outcomes measured using household surveys and administrative data.

The Bayesian Approach to Decision Making and Analysis in Nutrition Research and Practice.

This is part of a series of monographs on research design and analysis. The purpose of this article is to describe the purposes of and approach to conducting Bayesian decision making and analysis. Bayesian decision making involves basing decisions on the probability of a successful outcome, where this probability is informed by both prior information and new evidence the decision maker obtains.

What is translational research? Concepts and applications in nutrition and dietetics.

This monograph is tenth in a series of articles focused on research design and analysis, and provides an overview of translational research concepts. Specifically, this article presents models and processes describing translational research, defines key terms, discusses methodological considerations for speeding the translation of nutrition research into practice, illustrates application of translational research concepts for nutrition practitioners and researchers, and provides examples of translational research resources and training opportunities. To promote the efficiency and translation of evidence-based nutrition guidelines into routine clinical-, community-, and policy-based practice, the dissemination and implementation phases of translational research are highlighted and illustrated in this monograph.

Publishing nutrition research: a review of multivariate techniques--part 3: data reduction methods.

This is the ninth in a series of monographs on research design and analysis, and the third in a set of these monographs devoted to multivariate methods. The purpose of this article is to provide an overview of data reduction methods, including principal components analysis, factor analysis, reduced rank regression, and cluster analysis. In the field of nutrition, data reduction methods can be used for three general purposes: for descriptive analysis in which large sets of variables are efficiently summarized, to create variables to be used in subsequent analysis and hypothesis testing, and in questionnaire development.

Publishing nutrition research: a review of multivariate techniques--part 2: analysis of variance.

This article is the eighth in a series exploring the importance of research design, statistical analysis, and epidemiology in nutrition and dietetics research, and the second in a series focused on multivariate statistical analytical techniques. The purpose of this review is to examine the statistical technique, analysis of variance (ANOVA), from its simplest to multivariate applications. Many dietetics practitioners are familiar with basic ANOVA, but less informed of the multivariate applications such as multiway ANOVA, repeated-measures ANOVA, analysis of covariance, multiple ANOVA, and multiple analysis of covariance.

Publishing nutrition research: validity, reliability, and diagnostic test assessment in nutrition-related research.

This is the sixth in a series of monographs on research design and analysis. The purpose of this article is to describe and discuss several concepts related to the measurement of nutrition-related characteristics and outcomes, including validity, reliability, and diagnostic tests. The article reviews the methodologic issues related to capturing the various aspects of a given nutrition measure's reliability, including test-retest, inter-item, and interobserver or inter-rater reliability.

School food environments and practices affect dietary behaviors of US public school children.

Background: Changes to school food environments and practices that lead to improved dietary behavior are a powerful strategy to reverse the childhood obesity epidemic.

Objectives: To estimate the effects of school food environments and practices, characterized by access to competitive foods and beverages, school lunches, and nutrition promotion, on children's consumption of sugar-sweetened beverages, low-nutrient energy-dense foods, and fruits/vegetables at school.

Design: Cross-sectional study using data from the third School Nutrition Dietary Assessment Study, a nationally representative sample of public school districts, schools, and children in school year 2004-2005.

Consumption of low-nutrient, energy-dense foods and beverages at school, home, and other locations among school lunch participants and nonparticipants.

Background: Access to foods and beverages on school campuses, at home, and other locations affects children's diet quality, energy intake, and risk of obesity.

Objectives: To describe patterns of consumption of "empty calories"--low-nutrient, energy-dense foods, including sugar-sweetened beverages--by eating location among National School Lunch Program (NSLP) participants and nonparticipants.

Design: Cross-sectional study using 24-hour dietary recall data from the 2004-2005 third School Nutrition Dietary Assessment Study.

School breakfast program but not school lunch program participation is associated with lower body mass index.

Background: Rates of overweight and obesity have increased dramatically during the past 2 decades. Children obtain a large fraction of their food energy while at school.

Objective: To estimate the relationship between participation in school meal programs and children's body mass index (BMI) and their likelihood of being overweight or obese, testing the hypothesis that school meal participation influences students' weight status, as measured by their BMI and indicators of overweight and obesity.

Association between school food environment and practices and body mass index of US public school children.

Background: With the ongoing interest in implementing school policies to address the problem of childhood obesity, there is a need for information about the relationships between school food environments and practices and children's weight status.

Objective: To examine the association between school food environments and practices and children's body mass index (BMI; calculated as kg/m(2)).

Design: The study used data from the third School Nutrition Dietary Assessment Study, a cross-sectional study that included a national sample of public school districts, schools, and children in the 2004-2005 school year.

An introduction to qualitative research for food and nutrition professionals.

The purpose of this article is to define qualitative research, explain its design, explore its congruence with quantitative research, and provide examples of its applications in dietetics. Also, methods to ensure validity, reliability, and relevance are addressed. Readers will gain increased knowledge about qualitative research and greater competency in evaluating this type of research.

Using Dietary Reference Intake-based methods to estimate the prevalence of inadequate nutrient intake among school-aged children.

Objective: To estimate the prevalence of inadequate usual intakes of nutrients by school-aged children.

Design: A descriptive study using data from the US Department of Agriculture 1994 to 1996 Continuing Survey of Food Intake by Individuals. Each subject provided two 24-hour recalls.