Friday, April 16, 1999
04:30 PM in MATH 175.
Myra Samuels Memorial Lecture
Professor Raymond J. Carroll, University Distinguished Professor, Professor of Statistics, Texas A&M University

The Statistical Problem of Relating Nutrient Intake and Disease

Abstract

Most observation studies in nutritional epidemiology attempt to relate disease and nutrient intakes by measuring the latter using an instrument called a food frequency questionnaire (FFQ). The FFQ is a self-report of typical eating patterns and amounts, and is as such subject to biases and errors of measurement. Recently, there has been considerable controversy concerning the existence of a relationship between total fat intake as measured by the FFQ and breast cancer. I will review this controversy and discuss the subtle statistical issues that arise. In particular, the issue of whether the FFQ has any statistical power to detect a fat-breast cancer relationship will be discussed. Analyzing the issue inevitably leads to an investigation of how FFQ's are related to real (usual) intake of a nutrient. I will present a simple statistical model that is sufficiently flexible as to provide a continuum between the extremes of the FFQ being a powerful instrument and the FFQ being of little value, and I will discuss a new study which will attempt to resolve between the extremes.

A reception will follow the seminar at 5:30 p.m. in the Mathematical Sciences Library Lounge.