Development of the Two-Stage Rapid Estimate of Adult Literacy in Dentistry

Objective: This work proposes a revision of the 30 item Rapid Estimate of Adult Literacy in Dentistry (REALD-30), into a more efficient and easier-to-use two-stage scale. Methods: Using a sample of 1405 individuals (primarily women) enrolled in a Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), the present work utilizes principles of item response theory and multi-stage testing to revise the REALD-30 into a two-stage test of oral health literacy, named Two-Stage REALD or TS-REALD, which maximizes score precision at various levels of participant ability. Results: Based on the participant's score on the five-item first-stage (i.e., routing test), one of three potential stage-two tests is administered: a four-item Low Literacy test, a six-item Average Literacy test, or a three-item High Literacy test. Conclusions: The reliability of scores for the TS-REALD is >0.85 for a wide range of ability. The TS-REALD was found to be predictive of perceived impact of oral conditions on well-being, after controlling for educational level, overall health, dental health, and a general health literacy measure. While containing approximately one-third of the items on the original scale, the TS-REALD was found to maintain similar psychometric qualities.