Discriminant validity of the CAST instrument compared to the dmf index in the deciduous dentition: a cross sectional study

Abstract This study aimed to assess the discriminant validity of the Caries Assessment Spectrum and Treatment (CAST) at different thresholds, compared with the Decayed, Missing, and Filled Teeth Index (dmf) instrument, to discriminate caries risk factors. A cross-sectional study was conducted including children aged 2-5 years from preschools in Southern Brazil. Parents answered a questionnaire, and children were clinically examined using the CAST instrument and, in the following weeks, using the dmf index. Two caries thresholds were adopted for CAST: caries in dentin (CAST4-7/CAST2,4-8) and enamel caries (CAST3-7/CAST2-8). Poisson regression was used in the analysis (p