title: Fourth-grade children's dietary recall accuracy is influenced by retention interval (target period and interview time).
abstract: BACKGROUND
  For a 24-hour dietary recall, two possible target periods are the prior 24 hours (24 hours immediately preceding the interview time) and previous day (midnight to midnight of the day before the interview), and three possible interview times are morning, afternoon, and evening. Target period and interview time determine the retention interval (elapsed time between to-be-reported meals and the interview), which, along with intervening meals, can influence reporting accuracy.
  
  
  OBJECTIVE
  The effects of target period and interview time on children's accuracy for reporting school meals during 24-hour dietary recalls were investigated. DESIGN AND SUBJECTS/SETTING: During the 2004-2005, 2005-2006, and 2006-2007 school years in Columbia, SC, each of 374 randomly selected fourth-grade children (96% African American) was observed eating two consecutive school meals (breakfast and lunch) and interviewed to obtain a 24-hour dietary recall using one of six conditions defined by crossing two target periods with three interview times. Each condition had 62 or 64 children (half boys).
  
  
  METHODS
  Accuracy for reporting school meals was quantified by calculating rates for omissions (food items observed eaten but unreported) and intrusions (food items reported eaten but unobserved); a measure of total inaccuracy combined errors for reporting food items and amounts.
  
  
  METHODS
  For each accuracy measure, analysis of variance was conducted with target period, interview time, their interaction, sex, interviewer, and school year in the model.
  
  
  RESULTS
  There was a target-period effect and a target-period by interview-time interaction on omission rates, intrusion rates, and total inaccuracy (six P values <0.004). For prior-24-hour recalls compared to previous-day recalls, and for prior-24-hour recalls in the afternoon and evening compared to previous-day recalls in the afternoon and evening, omission rates were better by one third, intrusion rates were better by one half, and total inaccuracy was better by one third.
  
  
  CONCLUSIONS
  To enhance children's dietary recall accuracy, target periods and interview times that minimize the retention interval should be chosen.
authors.affiliation: Institute for Families in Society, University of South Carolina, 1600 Hampton St, Suite 507, Columbia, SC 29208, USA. sbaxter@mailbox.sc.edu
authors.forename: Suzanne Domel
authors.initials: SD
authors.lastname: Baxter
authors.forename: James W
authors.initials: JW
authors.lastname: Hardin
authors.forename: Caroline H
authors.initials: CH
authors.lastname: Guinn
authors.forename: Julie A
authors.initials: JA
authors.lastname: Royer
authors.forename: Alyssa J
authors.initials: AJ
authors.lastname: Mackelprang
authors.forename: Albert F
authors.initials: AF
authors.lastname: Smith
mesh_terms: D000704:Analysis of Variance; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D005260:Female; D006801:Humans; D007407:Interviews as Topic / Q000379:methods* / Q000592:standards*; D008297:Male; D011939:Mental Recall; D002666:Psychology, Child; D015203:Reproducibility of Results; D012574:Schools; D012650:Self Disclosure; D012680:Sensitivity and Specificity; D013022:South Carolina; D013334:Students / Q000523:psychology*; D013997:Time Factors