Pilot studies are often recommended by scholars and consultants to address a variety of issues, including preliminary scale or instrument development. Specific concerns such as item difficulty, item discrimination, internal consistency, response rates, and parameter estimation in general are all relevant. Unfortunately, there is little discussion in the extant literature of how to determine appropriate sample sizes for these types of pilot studies. This article investigates the choice of sample size for pilot studies from a perspective particularly related to instrument development. Specific recommendations are made for researchers regarding how many participants they should use in a pilot study for initial scale development.

The Food, Math, and Science Teaching Enhancement Resource (FoodMASTER) Initiative is a compilation of programs aimed at using food as a tool to teach mathematics and science. In 2007-2008, a foods curriculum developed by professionals in nutrition and education was implemented in 10 3 rd -grade classrooms in Appalachian Ohio; teachers in these classrooms implemented 45 hands-on foods activities that covered 10 food topics. Subjects included measurement; food safety; vegetables; fruits; milk and cheese; meat, poultry, and fish; eggs; fats; grains; and meal management. Students in four other classrooms served as the control group. Mainstream 3 rd -grade students were targeted because of their receptiveness to the subject matter, science standards for upper elementary grades, and testing that the students would undergo in 4 th grade. Teachers and students alike reported that the hands-on FoodMASTER curriculum experience was worthwhile and enjoyable. Our initial classroom observation indicated that the majority of students, girls and boys included, were very excited about the activities, became increasingly interested in the subject matter of food, and were able to conduct scientific observations.

Adequate sample sizes for omnibus ANOVA tests do not necessarily provide sufficient statistical power for post hoc multiple comparisons typically performed following a significant omnibus F test. Results reported support a comparison-of-most-interest approach for sample size determination in ANOVA based on effect sizes for multiple comparisons.

In 2009, DeMars stated that when impact exists there will be Type I error inflation, especially with larger sample sizes and larger discrimination parameters for items. One purpose of this study is to present the patterns of Type I error rates using Mantel–Haenszel (MH) and logistic regression (LR) procedures when the mean ability between the focal and reference groups varies from zero to one standard deviation. The findings can be used as guides for alpha adjustment when using MH or LR methods when impact exists. A second purpose is to better understand the conditions that cause Type I error rates to inflate. The results indicate that inflation can be controlled even in the presence of large ability differences and with large samples.

BACKGROUND Children in Appalachia are experiencing high levels of obesity, in large measure because of inferior diets. This study screened the dietary intake of third-graders residing in three rural Appalachian counties in Ohio and determined whether the Food, Math, and Science Teaching Enhancement Resource Initiative (FoodMASTER) curriculum improved their dietary intake. METHODS Dietary intake was measured for 238 third-graders at the beginning of the 2007-2008 school year and for 224 third-graders at the end of that year. The FoodMASTER curriculum was delivered to 204 students (test group). Intake was measured using the Block Food Frequency Questionnaire 2004. The final analysis included 138 students. RESUTS The FoodMASTER curriculum did not significantly affect the diets of the students in the test group, as no significant differences in intake of macronutrients, specific nutrients, or food groups were found between the test and control groups. Majorities of students did not meet the Recommended Dietary Allowance or Adequate Intakes for fiber, calcium, iron, vitamin A, and vitamin E. The students as a whole did not meet the MyPyramid recommendations for any food group, and nearly one-fifth of their calories came from sweets. Significant differences in percentages of kilocalories from protein and sweets and in servings of fats, oils, and sweets were seen between groups of higher and lower socioeconomic status. CONCLUSIONS Energy-dense foods are replacing healthy foods in the diets of Ohio children living in rural Appalachia. The prevalence of poor dietary intake in Appalachia warrants further nutrition interventions involving programming for nutrition, such as future FoodMASTER curricula.