Development of the Korean health literacy instrument for adults

Abstract

Known for the relationship between low literacy and poor health outcomes, health literacy has recently emerged as a key concept in health care service studies. In Korea, studies to identify health literacy levels for adults have seen very limited research. Most widely used health literacy instruments are not available for Korean adults due to differences in language, health care systems, and cultural context. The purpose of the study was to develop and validate a health literacy instrument that measures skills in understanding and using health-related information, and making informed health decision in Korean adults.The process of instrument development consisted of four phases: In phase 1, the conceptual framework was constructed based on the review of literature. The Korean Health Literacy Instrument (KHLI) was included three components designed to measure health literacy skills: (a) dimensions, (b) general literacy skills for tasks, and (c) health contexts. The dimensions consisted of functional, interactive, and critical health literacy. General literacy skills for tasks were categorized into prose, document, and numeracy. In addition, health contexts were categorized into health promotion, disease management, and health navigation. A total of 33 initial items were generated based on the conceptual framework of this study.In phase 2, content validity assessment was conducted by an expert panel, and the 33 items were reduced to 28 items based on the CVI results with cut point of .80. After a pilot study, the 28 items were reduced to 22 items because the results showed readability and formatting problems.Phase 3 consisted of a preliminary test and item analysis for revision. The 22 items were administered to a convenient sample of 292 adults from community and outpatient hospital settings. The average administration time was 25.45 minutes. Exploratory factor analysis was performed to identify a number of factors. Item analysis was conducted to estimate item difficulty and item discrimination for item revision and elimination. Therefore, 4 items of 22 items were deleted from KHLI because item discrimination index was fairly low scores.In phase 4, the final test was conducted with 315 adults aged 40-64 years from community and outpatient hospitals and clinics. The average administration time was 24.29 minutes. Confirmatory factor analysis was performed to test the construct validity of the instrument, the unidimensionality, and then, a three-factor model was appropriately presented to the structure of the KHLI (RMSEA .036, CFI .959, and TLI .970). From the remaining 18 items, no items were eliminated. Overall, in this instrument, an internal consistency reliability coefficient of .82 and test-retest reliability was .89 indicating adequate stability. The reliability of the coefficient for each dimension ranged from .536 to .663. The mean score of the KHLI was 11.98 with a range of 0–18 indicating the scores of health literacy skills. The 40-49 years adult group had a significantly higher score of health literacy than the 60-64 years adult age group (F=21.896, p = < .001). Also, respondents with high monthly household income and education had a significantly higher score of health literacy (F=5.510, p < .001). Health problems and health education were not associated as statistically significant with health literacy.In conclusion, KHLI was suitable for screening individuals who had limited health literacy skills. Based on the findings of this study, future studies should continue empirical investigations on the KHLI, its psychometric properties, and validation process.