Efficacy of instruments measuring oral health literacy: a systematic review.

PURPOSE: To identify and review the psychometric properties of instruments available for measuring oral health literacy. MATERIALS AND METHODS: A comprehensive computerised search was carried out using six databases. The final papers were rated for level of evidence and scientific quality. RESULTS: A total of 621 potentially relevant articles were retrieved in the primary search. Twenty-nine studies using 13 oral health literacy instruments were included in the final analysis. After applying an international standards framework, all included studies were categorised as evidence level '2c'. Qualities of evidence were rated with STROBE guidelines. Psychometric analysis indicated various levels of validity and reliability across the instruments. CONCLUSIONS: As an emerging field, the number and reliability of oral health literacy instruments is rapidly growing, although many are in preliminary stages of testing. The majority of these focus on functional literacy and were developed in English for North American contexts. Further work is indicated to measure oral health literacy as a wider construct across diverse populations.