@article{d71ac976d1734ccdae9efc9e1ba7d957,
title = "{A figure is presented}Cruciferous Vegetable Intake Questionnaire Improves Cruciferous Vegetable Intake Estimates",
abstract = "Objective: To develop a validated, focused Cruciferous Vegetable Food Frequency Questionnaire (FFQ) as an assessment tool for specific quantification of dietary cruciferous vegetable exposure. Design/Methods: Participants (n=107; 18 to 76 years old) completed a standard FFQ and the Cruciferous Vegetable FFQ twice over a 2-week period. Repeat dietary recalls were collected on 3 days over the same 2-week period. Urinary dithiocarbamate was determined as a biomarker of cruciferous vegetable intake. Statistical Analyses: Descriptive statistics of intake; paired t tests and sign tests for comparison of intake estimates between instruments; Spearman correlations to assess reliability and associations between diet instruments and urinary dithiocarbamate. Results: Cruciferous vegetable intake was significantly correlated between the two FFQs (rs=0.58), although the Cruciferous Vegetable FFQ estimated intake 35 g higher than the standard FFQ. The Cruciferous Vegetable FFQ was reliable, with a repeated measures correlation of 0.69 (P≤0.01). Urinary dithiocarbamate excretion correlated with cruciferous vegetable intake from the Cruciferous Vegetable FFQ (rs=0.26, P<0.01), and from the standard FFQ (rs=0.19, P=0.06). Conclusions: The Cruciferous Vegetable FFQ provided a reproducible, valid estimate of cruciferous vegetable exposure and improved the relationship between crucifer consumption and urinary dithiocarbamate, a biomarker of cruciferous vegetable exposure. The nearly twofold difference in exposure estimates between the Cruciferous Vegetable FFQ and the standard FFQ could change the statistical significance of risk estimates in the context of epidemiological research. This questionnaire is an appropriate research tool to evaluate cruciferous vegetable intake more accurately than a standard FFQ, particularly in the context of dietary intervention studies that promote increased vegetable intake to reduce the risk for chronic disease.",
author = "Thomson, {Cynthia A.} and Newton, {Tara R.} and Graver, {Ellen J.} and Jackson, {Kelly A.} and Reid, {Phyllis M.} and Hartz, {Vernon L.} and Cussler, {Ellen C.} and Hakim, {Iman A.}",
note = "Funding Information: Despite limitations, the focused Cruciferous Vegetable FFQ instrument was more strongly positively correlated with the selected biomarker of intake than was a standard FFQ instrument and affords an opportunity to more accurately assess exposure to cruciferous vegetables and potentially the biologically active constituents. The availability of a focused Cruciferous Vegetable FFQ allows for more accurate assessment of cruciferous vegetable exposure in the context of epidemiological research in a more cost-effective manner than repeat dietary recalls. Efforts to assess cruciferous vegetable intake using a valid instrument are an essential first step to advancing the understanding of the potential role of crucifer consumption in chronic disease risk reduction. Estimates of risk reduction that lead to the quantification of “optimal” intake in terms of both total and specific cruciferous vegetables are an essential first step in the development of guidelines for cruciferous vegetable intake among individuals and populations at risk for chronic disease. This study was supported by National Cancer Institute grants KO7 CA093658 and CA23074. The authors thank Tracy Crane for assistance with recruiting, John Stroster for biological sample collection and processing, David S. Alberts for his patient and insightful mentoring, Dr Paul Talalay{\textquoteright}s laboratory for the analysis of 24-hour urinary dithiocarbamate concentrations, and the volunteers who participated in the focus groups and validation study. T. R. Newton and P. M. Reid are research specialists, senior, and K. A. Jackson is lecturer and assistant director of the Didactic Program in Dietetics, Department of Nutritional Sciences, The University of Arizona, Tucson. At the time of the study, K. A. Jackson was a graduate student in the Department of Nutritional Sciences, The University of Arizona, Tucson. E. J. Graver is research specialist, principal and V. L. Hartz is a computer database specialist, senior, Diet and Behavioral Measurements Center, Arizona Cancer Center, The University of Arizona, Tucson. E. C. Cussler is a research specialist, senior, Department of Physiology, The University of Arizona, Tucson. I. A. Hakim is professor and director of the Division of Health Promotion Sciences, Mel and Enid Zuckerman College of Public Health, and Arizona Cancer Center, The University of Arizona, Tucson. ",
year = "2007",
month = apr,
doi = "10.1016/j.jada.2007.01.016",
language = "English (US)",
volume = "107",
pages = "631--643",
journal = "Journal of the American Dietetic Association",
issn = "0002-8223",
publisher = "Elsevier USA",
number = "4",
}