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Differences in Fourth-Graders' Participation Rates Across Four School-Based Nutrition Studies
Abstract:
Federal policy has encouraged researchers to include children in research studies; thus, it is important to report experiences recruiting children to participate in studies. This article compares fourth-graders' participation rates across four school-based nutrition studies conducted in one school district in a southeastern state. For each study, children were observed eating school meals (breakfast and lunch); interviewed regarding dietary intake; and weighed and measured. For Study 1, children from 11 schools received $10 per interview for up to two interviews conducted in the morning at school. For Study 2, children from 10 schools received $25 if interviewed once in the evening, either by telephone or in a van parked outside the child's home. For Study 3, children from three schools received $10 per interview for up to three interviews held in the evening by telephone. For Study 4, children from six schools received $15 per interview for up to two interviews conducted either in the morning or afternoon at school, or in the evening by telephone. Recruitment procedures were similar for all studies.Participation rates were 73% (n=635) for Study 1, 57% (n=432) for Study 2, 66% (n=158) for Study 3, and 71% (n=296) for Study 4. Logistic regression was used to determine whether study (1, 2, 3, 4), race (black, white), or gender (male, female) were significant predictors of participation (agreed, denied). The results indicated that study (p<0.0001), race (p=0.0198), and gender (p=0.0188) were significant predictors, however, no two-factor interactions among these effects were significant. Post hoc pairwise comparisons with Bonferroni adjustment indicated that agreement to participate for Study 2 was lower (p<0.0001) than that for Studies 1, 3, and 4, which did not differ. Agreement to participate across all four studies was higher for black (69%) than white (63%; p=0.0054) children and for females (69%) than males (64%; p=0.0209). Schools provide a natural environment for nutrition research because school foodservice programs feed millions of children one or two meals (breakfast and/or lunch) each school day. Observations of children eating school meals provide a convenient and relatively unobtrusive means of validating children's dietary recalls. Thus, at some point, most child nutrition professionals are likely to be involved in research either directly (i.e. by conducting studies themselves) or indirectly (i.e. by allowing others access to their school cafeterias to collect data).This paper references the following data:Table 1. Similarities and Differences in the Designs for Each of the Four Studies.Table 2. Number and Percent of Fourth-Grade Children Who Agreed or Denied to Participate by Race and Gender Across all Four Studies Combined.Table 3. Number and Percent of Fourth-Grade Children Who Agreed or Denied to Participate by Gender and Race for Each of the Four Studies Separately.
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