Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1997-8-7
pubmed:abstractText
Cancer prevention clinical trials use food frequency questionnaires (FFQs) to assist in eligibility screening. FFQ reliability and validity studies are available, but these studies do not evaluate FFQs as screening tools. The Wheat Bran Fiber Trial of the University of Arizona used a FFQ as an eligibility screen with the goal of screening out subjects whose true daily calcium intake was less than 500 mg per day (for safety) and whose true dietary fiber intake was greater than 30 g per day (for safety and trial efficiency). Subjects ineligible by FFQ were interviewed for final dietary eligibility determinations. A study was undertaken within the Wheat Bran Fiber Trial to evaluate the sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of the FFQ used in this context. Four-day food records were collected on 183 potential participants before entry into the study. Using the 4-day averages as the "true" value, sensitivity, specificity, positive predictive value, and NPV were calculated for men and women separately under two screening conditions: using the target calcium and dietary fiber values and using "revised" values identified in interim analysis within the study. NPV was acceptable in all analyses. Sensitivity for low calcium intake was inadequate under the original criteria (0.33 for men and 0.09 for women) but acceptable under the revised criteria (0.80 for men and 0.81 for women). With the revised criteria, specificity declined, resulting in heavy screening burdens deemed worthwhile for the safety considerations. Dietary fiber eligibility screening worked well at target values. These differences were not predicted by reliability/validity studies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1055-9965
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
347-54
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:9149895-Adult, pubmed-meshheading:9149895-Aged, pubmed-meshheading:9149895-Aged, 80 and over, pubmed-meshheading:9149895-Arizona, pubmed-meshheading:9149895-Calcium, Dietary, pubmed-meshheading:9149895-Cohort Studies, pubmed-meshheading:9149895-Colonic Neoplasms, pubmed-meshheading:9149895-Colonic Polyps, pubmed-meshheading:9149895-Diet Records, pubmed-meshheading:9149895-Dietary Fiber, pubmed-meshheading:9149895-Eligibility Determination, pubmed-meshheading:9149895-Female, pubmed-meshheading:9149895-Food Habits, pubmed-meshheading:9149895-Humans, pubmed-meshheading:9149895-Male, pubmed-meshheading:9149895-Mass Screening, pubmed-meshheading:9149895-Middle Aged, pubmed-meshheading:9149895-Neoplasm Recurrence, Local, pubmed-meshheading:9149895-Nutrition Surveys, pubmed-meshheading:9149895-Patient Selection, pubmed-meshheading:9149895-Reproducibility of Results, pubmed-meshheading:9149895-Risk
pubmed:year
1997
pubmed:articleTitle
Use of a food frequency questionnaire to screen for dietary eligibility in a randomized cancer prevention phase III trial.
pubmed:affiliation
Department of Family and Community Medicine, Arizona Cancer Center, University of Arizona 85724, USA.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Randomized Controlled Trial, Clinical Trial, Phase III