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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. The article addresses all these applications and includes hypothetical and real examples from the field of dietetics., (Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)

This article is the seventh in a series reviewing the importance of research design, analyses, and epidemiology in the conduct, interpretation, and publication of nutrition research. Although there are a variety of factors to consider before conducting nutrition research, the techniques used to conduct the statistical analysis are fundamental for translating raw data into interpretable findings. The statistical approach must be considered during the design phase of any study and often involves the use of multivariate analytical techniques. Multivariate analytical techniques represent a variety of mathematical models used to measure and quantify an exposure-disease or an exposure-outcome association, taking into account important factors that can influence this relationship. The primary purpose of this review is to introduce the more commonly used multivariate techniques, including linear and logistic regression (simple and multiple), and survival analyses (Kaplan Meier plots and Cox regression). These techniques are described in detail, providing basic definitions and practical examples with nutrition relevancy. An appreciation for the general principles within and presented previously in this article series is vital for enhancing the rigor in which nutrition-related research is implemented, reviewed, and published., (Copyright © 2011 American Dietetic Association. Published by Elsevier Inc. All rights reserved.)

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. Similarly, it covers content validity, indicators of absolute vs relative validity, and internal vs external validity. With respect to diagnostic assessment, the article summarizes the concepts of sensitivity and specificity. The hope is that dietetics practitioners will be able to both use high-quality measures of nutrition concepts in their research and recognize these measures in research completed by others., (Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.)

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. The hope is that food and nutrition professionals will be inspired to conduct and publish qualitative research, adding to the body of peer-reviewed dietetics-related qualitative publications. This type of research must be methodically planned and implemented with attention to validity, reliability, and relevance. This rigorous approach boosts the probability that the research will add to the scientific literature and qualify for publication.

This is the third article in a periodic five-part series on publishing nutrition research. These monographs are designed to assist in the interpretation of the Journal of the American Dietetic Association author guidelines and provide guidance in publishing and interpreting nutrition-related research articles. This installment focuses on the use of nonparametric statistical methods. The rationale for their use, their advantages and disadvantages, nonparametric alternatives to parametric tests, nonparametric statistical analysis, examples of their use, and helpful resources for further study are topics and issues addressed in this article.

To enhance the Journal's position as the premier source for peer-reviewed research in the science of food, nutrition, and dietetics, members of the Board of Editors recognize the importance of providing a resource for researchers to ensure quality and accuracy of reporting in the Journal. This first monograph of a periodic four-part series focuses on the study hypothesis, study design, and collaboration with a statistician. The basics of study design start with a clear hypothesis or research question and a definitive outcome measure. Throughout the development of a research project, the questions of what is to be discovered and why the research is being conducted need to be addressed. Decisions about parameters to measure and study design most appropriate to test a hypothesis create the foundation for future conclusions. Collaboration with a statistician can aid in the research development process. Documentation that coherently communicates the research process will advance the science of evidence-based practice in nutrition and dietetics. Real examples from published literature are provided, as well as references to books and online resources.

ABSTRACT Object To determine if adult patients who received marrow transplants had faster resumption of oral energy and nutrient intake and shorter duration of intravenous (TV) fluid requirement if discharged [...]