Validity and reliability of the Portuguese version of the rapid estimate of adult literacy in dentistry: REALD-29 PT

Background Health literacy is a main factor in health for its improvement, allowing the individuals to have a greater capacity to engage and participate in collective health promotion actions. The evaluation of functional health literacy is essential to determine the ability that each individual has to understand basic health information. The present study aimed to perform the translation and cross-cultural adaptation of the Rapid Estimate of Adult Literacy in Dentistry-30 to the Portuguese language and test the reliability and validity of this version. Methods After translation and cultural adaptation, the instrument was applied to a group of individuals that participate in the program Atividade Senior, developed by the municipality of Viseu, Portugal. The final sample was composed by 206 participants that accepted responding to the translated version of the instrument. Statistical validation was accomplished to complete the process and obtain the final instrument. One question was removed for the creation of the final instrument with 29 questions, therefore being named Rapid Estimate of Adult Literacy in Dentistry-29 PT. Results The Rapid Estimate of Adult Literacy in Dentistry-29 PT presented good internal reliability. Cronbach’s alpha ranged from 0.89 to 0.90 when words were deleted individually. The analysis of test–retest reliability revealed excellent reproducibility. We can verify that the Rapid Estimate of Adult Literacy in Dentistry-29 PT scale for assessment of oral health literacy among older adults presents an acceptable internal consistency, with a global Cronbach´s alpha of 0.894. Conclusions The new scale can be applied to assess oral health literacy among older Portuguese adults, presenting an acceptable internal consistency and is validated to assess oral health literacy and is crucial in epidemiological studies.