Development and validation of a questionnaire about fluoride knowledge.

Objective: To develop and validate a questionnaire about fluoride knowledge (FKQ).

Methods: Questions to evaluate knowledge about fluoride sources and daily fluoridated water and dentifrices consumption were developed and validated. Sociodemographic data were also collected from the participants, and data were collected for testing their psychometric properties and instrument validation. The model adjustment was tested in 456 dentists, students, and health personnel via confirmatory factor analysis (CFA) with unidimensional categorical indicators. Cronbach's alpha coefficient was used to estimate the instrument's reliability. External validation measurements were represented by questions related to sociodemographic data, fluoride source knowledge and daily practices, and the consumption of fluoride water and dentifrices.

Results: The model showed adequate fit via confirmatory factor analysis (CFA); the fit indices were comparative fit index (CFI) = 0.941, Tucker‒Lewis index (TLI) = 0.927, and root mean square error of approximation (RMSEA) = 0.075, with factorial loadings varying between 0.25 and 0.91. The Cronbach's alpha coefficient for the 13 items was 0.68, demonstrating substantial and adequate reliability in the total instrument.

Conclusion: The FKQ can estimate the knowledge of dentists, dental students, and health personnel about fluoride use.