Invited commentary: Factor analysis and the search for objectivity.

  title={Invited commentary: Factor analysis and the search for objectivity.},
  author={Mar{\'i}a Elena Mart{\'i}nez and James Arthur Robert Marshall and Lee B Sechrest},
  journal={American journal of epidemiology},
  volume={148 1},
A key concern in nutritional epidemiology is the complex nature of the exposure assessed by means of dietary questionnaires. Unlike other exposures, diet is so complex that special knowledge is required to ensure that the correct exposure measure is used. A clear definition of the food or nutrient of interest and knowledge of how it may affect the disease or outcome of interest is imperative. Food consists of nutrients as well as other substances, such as additives, naturally occurring… CONTINUE READING