Development and validation of Hong Kong Rapid Estimate of Adult Literacy in Dentistry

Abstract

To develop and validate an instrument, the Hong Kong Rapid Estimate of Adult Literacy in Dentistry (HKREALD-30). The Rapid Estimate of Adult Literacy in Dentistry (REALD-99) was translated into Chinese and modified in the pretest. A total of 200 parents of pediatric dental patients were interviewed using this modified scale and administered additional three sets of self-reported questionnaires. The 99 items of the scale were reduced to 30 (HKREALD-30). Concurrent validity was tested by comparing the HKREALD-30 scores with the participants' educational level, pattern of dental visits and reading habits. Convergent validity was tested by examining the association between HKREALD-30 and the Test of Functional Health Literacy in Dentistry (TOFHLiD). The test-retest reliability and internal consistency of HKREALD-30 were also evaluated. A significant correlation (P < 0.01) was found between HKREALD-30 and participants' reading habits. HKREALD-30 was also highly correlated with TOFHLiD (Spearman's rho = 0.693, P < 0.01). In the regression model, HKREALD-30 was positively associated with TOFHLiD (P < 0.05) after controlling for participants' characteristics. The intra-class correlation coefficient of HKREALD-30 was 0.78 and the Cronbach's alpha was 0.84. Initial testing of HKREALD-30 suggested that it is a valid and reliable instrument for the basic screening of oral health literacy among Chinese people in Hong Kong.