Abstract
OBJECTIVES: To develop and validate a Dental Nutrition Knowledge Competency Scale to assess dental health-related nutrition knowledge of low-income women. METHODS: A literature search for dietary practices/factors related to dental caries was conducted and the generated items were incorporated into an initial questionnaire. A panel of 10 nutrition experts evaluated it for its content, readability, relevance and bias, then a focus group of six low-income women determined its readability and comprehension. The questionnaire was administered to a total of 150 low-income women, ages 18–50 years, from Central Texas. Construct validity was evaluated by item difficulty, item discrimination and factor analysis. Internal consistency reliability was determined via calculation of Cronbach's alpha. Test-retest reliability was established via bivariate correlations between total scores at two time points for a subsample of 40 women. Paired sample t-tests were conducted to examine for differences between test scores at the two time points, 2 weeks apart. RESULTS: Item difficulty and discrimination analysis resulted in elimination of eight questions; factor analysis then found 24 items that loaded on three different factors. These included knowledge of: foods/factors that affect dental caries, added sugars in foods and on food labels and recommended frequency of oral hygiene practices. The subscales and the completed scale exhibited good internal consistency (0.7 ± 0.014) and test-retest reliability (0.8 ± 0.015). CONCLUSIONS: The Dental Nutrition Knowledge Competency Scale is a validated and reliable instrument to assess nutrition knowledge related to dental health in low-income women. FUNDING SOURCES: The Bess Heflin Centennial Professorship.