How accurate are parental responses concerning their fourth-grade children's school-meal participation, and what is the relationship between children's body mass index and school-meal participation based on parental responses?

BACKGROUND: This article investigated (1) parental response accuracy of fourth-grade children's school-meal participation and whether accuracy differed by children's body mass index (BMI), sex, and race, and (2) the relationship between BMI and school-meal participation (based on parental responses). METHODS: Data were from four cross-sectional studies conducted from fall 1999 to spring 2003 with fourth-grade children from 13 schools total. Consent forms asked parents to report children's usual school-meal participation. As two studies' consent forms did not ask about lunch participation, complete data were available for breakfast on 1,496 children (51% Black; 49% boys) and for lunch on 785 children (46% Black; 48% boys). Researchers compiled nametag records (during meal observations) of meal participation on randomly selected days during children's fourth-grade school year for breakfast (average nametag days across studies: 7-35) and for lunch (average nametag days across studies: 4-10) and categorized participation as "usually" (≥ 50% of days) or "not usually" (< 50% of days). Weight and height were measured. Concerning parental response accuracy, marginal regression was used with agreement between parental responses and nametag records as the dependent variable; independent variables were BMI, age, sex, race, and study. Concerning a relationship between BMI and school-meal participation, marginal regression was used with BMI as the dependent variable; independent variables were breakfast participation, lunch participation, age, sex, race, and study. RESULTS: Concerning breakfast participation and lunch participation, 74% and 92% of parents provided accurate responses, respectively. Parental response accuracy was better for older children for breakfast and lunch participation, and for Black than White children for lunch participation. Usual school-meal participation was significantly related to children's BMI but in opposite directions -- positively for breakfast and inversely for lunch. CONCLUSIONS: Parental response accuracy of children's school-meal participation was moderately high; however, disparate effects for children's age and race warrant caution when relying on parental responses. The BMI results, which showed a relationship between school-meal participation (based on parental responses) and childhood obesity, conflict with results from a recent article that used data from the same four studies and found no significant relationship when participation was based on nametag records compiled for meal observations.