Design Concepts in Nutritional Epidemiology

Abstract This book provides a practical guide to the understanding, interpretation, and application of the principles of nutritional epidemiology, set in the context of public health nutrition. Relating dietary and nutritional exposures to health outcomes requires a rigorous approach to measurement of both the key exposure and outcome variables of interest and also the associated measurement errors. Moreover, the analysis of such data requires appropriate statistical approaches that take into account sampling, measurement techniques, and the role of confounders in the context of specific study designs. The first part of the book brings a practical focus to the scientific concepts underlying study design with emphasis on design, planning, and evaluation of nutritional epidemiological studies; issues of sampling, sample size and power; and an understanding of the impact of measurement error, with practical remedies. The second part deals with the problems of measurement and interpretation of a variety of variables relevant to nutritional epidemiology. It covers issues relating to determination of food consumption and nutrient intake and the strengths and weaknesses of approaches to such measurements; the strengths and weaknesses of biochemical markers as indicators of both nutrient intake and nutritional status; validation studies of dietary assessment; and assessment of the potential influence of socio-economic factors, anthropometric measurements, and gene-nutrient interactions on diet-health associations. The final part addresses the principles and interpretation of the main types of epidemiological study in the context of questions addressing relationships between diet and health, including issues of lag time and relevant exposure.