Insight into the origins of intrusions (reports of uneaten food items) in children's dietary recalls, based on data from a validation study of reporting accuracy over multiple recalls and school foodservice production records.

BACKGROUND: Intrusions in dietary recalls may originate in confusion of episodic memories manifested as temporal dating errors.
OBJECTIVE: Data from a validation study (concerning reporting accuracy over multiple recalls) and school foodservice production records were used to investigate origins of intrusions in school meals in children's 24-hour recalls. DESIGN/SUBJECTS/
SETTING: During the 1999-2000 school year, 104 fourth-grade children were observed eating school meals on 1 to 3 nonconsecutive days separated by >or=25 days, and interviewed about the previous day's intake in the morning on the day after each observation day. STATISTICAL ANALYSES PERFORMED: For breakfast and lunch separately, logistic regression was used to investigate the effect of time (ie, days) before the interview day on the probability that intrusions referred to items available in the school foodservice environment. Exploratory analyses were conducted for breakfast options observed and/or reported eaten.
RESULTS: For interviews in which reported meals met criteria to be considered school meals and that contained intrusions, of 634 and 699 items reported eaten at breakfast and lunch, respectively, 394 and 331 were intrusions. Availability in the school foodservice environment of items referred to by intrusions in reports of lunch, but not breakfast, decreased as days increased before the interview day (P=0.031 and P=0.285, respectively). Concerning breakfast, children observed eating a cold option (ie, ready-to-eat cereal, milk, juice, crackers [graham or animal]) almost always reported a cold option, whereas children observed eating a hot option (ie, non-ready-to-eat cereal entrée [eg, sausage biscuit], milk, and fruit or juice) reported a cold option in approximately 50% of interviews.
CONCLUSIONS: In children's 24-hour recalls, confusion of episodic memories contributes to intrusions in school lunch, and generic dietary information (eg, cold option items available daily) or confusion of episodic memories may contribute to intrusions in school breakfast. Understanding the origins of intrusions may help in developing interview methods to decrease the occurrence of intrusions.