Objectives: The purpose of this study was to develop an oral health literacy assessment tool for upper elementary school children, as well as to assess their overall oral health literacy.

Methods: This instrument, the oral health literacy assessment tool designed for children in Korea (OHLC-K), has been validated through a total of three sets of pretests. Twenty-eight preliminary assessment items were developed on the basis of various types of oral health education literature for children. They contained verbal and functional sections, and further classified into 2 cognitive processes (literal, inferential). Finally, the tools for assessing oral health literacy consist of a 20 question self-assessment questionnaire, with statistical score distribution of 0 to 20. Additionally, the relationship between oral health literacy and Korean abilities were verified using qualification examinations for elementary school graduation in Korean language. The final participants were 274 upper graders in 2 elementary schools located in Seoul and Uijeongbu-si. Cronbach’s α, the item discrimination and difficulty of the final development tool were evaluated using the SPSS 23.0 and testAn 1.0 programs.

Results: The Cronbach’s α, item discrimination and difficulty of the final developed tool were .71, .35 and .75, respectively. The average oral health literacy score was 15.0. The lowest and highest % of correct answers were found in “Definition of periodontal disease (19.3%)” and “Definition of halitosis (92.7%)”, respectively. The mean score for oral health literacy was found to be 14.95 (±2.83, indicating circa 75% correct answers). The correlation coefficient for the Korean and OHLC-K scores was high (r=.73, P<.01). In the multiple linear regression, oral health literacy was associated with grade and gender. The higher oral health literacy score, the higher the Korean ability score was shown to be (r=.73, P<.01). Nevertheless, 12.5% of the children showed that their Korean abilities were above the standard, but their oral health literacy was below the same.

Summary and Conclusion: The tools developed in the course of this study could be used to measure the oral health literacy of children. As a results, it was found that Korean ability and oral health literacy were positively correlated. However, about 13% of children in the study had a good ability in Korean, but poor oral health literacy. Developing the ability to understand oral health information is vitally important for all children to maintain good oral health. It is necessary to pay more attention to children who exhibit poor oral health literacy.