Objectives To describe the ‘Caries Assessment Spectrum and Treatment’ (CAST) instrument, its origin and content, and to provide an example of how results can be reported. Methods The CAST instrument covers the complete range of stages of carious lesion progression: from no carious lesion, through caries protection (sealant) and lesion care (restoration) to lesions in enamel and dentine, the advanced stages of carious lesion progression in pulpal and its consequences on tooth‐surrounding tissue and tooth loss due to caries. Using the RAND modified e‐Delphi consensus method two independent panels, comprising a total of 56 epidemiologists from 27 countries, determined the face and content validity of CAST. Panellists assessed 17 statements related to the content, description, suitability and international use of CAST. Agreement of 75% or higher was required for reaching consensus on a statement. Construct validity and reliability testing of CAST have been carried out, but results are not yet available. Results All 17 statements were approved by the panellists, who found the RAND modified e‐Delphi consensus method suitable for achieving consensus. The CAST codes were ordered hierarchically. External validity was obtained. Reporting using CAST can be performed for orally healthy dentitions and those having morbidity and mortality. A DMF score can easily be calculated from the CAST codes, thereby enabling retention of the use of existing DMF scores. Conclusion The CAST instrument for use in epidemiological surveys is very promising. Face and content validation is obtained. Construct validity and reliability testing will be completed soon. A structure for reporting results in a comprehensive, pragmatic and easily understood way is being developed.

After a total of four rounds with the panel members and one round with the feedback group, the CAST index was approved for face and content validity. External validity was obtained. The participating epidemiologists found the RAND modified e-Delphi consensus method to be a suitable instrument for reaching consensus.

BackgroundThe Caries Assessment Spectrum and Treatment (CAST) is a new epidemiological instrument for detection and treatment of dental caries. Worldwide, the WHO criterion constitutes the epidemiological tool most commonly used for caries detection. The objective of the present study is to determine the levels of similarity and difference between the CAST instrument and WHO criterion on the basis of caries prevalence, dmf/DMF counts, examination time and reporting of results.MethodsAn epidemiological survey was carried out in Brazil among 6-11-year-old schoolchildren. Time of examinations was recorded. dmft, dmfs, DMFT and DMFS counts and dental caries prevalence were obtained according to the WHO criterion and the CAST instrument, as well the correlation coefficient between the two instruments.ResultsFour hundred nineteen children were examined. dmft and dmfs counts were 1.92 and 5.31 (CAST), 1.99 and 5.34 (WHO) with correlation coefficients (r) of 0.95 and 0.93, respectively. DMFT and DMFS counts were 0.20 and 0.33 (CAST), 0.19 and 0.30 (WHO), with r = 0.78 and r =0.72, respectively. Kappa coefficient values for intra-examiner consistency were CAST = 0.91-0.92; WHO = 0.95-0.96 and those for inter-examiner consistency were CAST = 0.90-0.96; WHO = 0.94-1.00. Mean time spent on applying CAST and WHO were 66.3 and 64.7 sec, respectively p = 0.26. The prevalence of dental caries using CAST (codes 2, 5-8) and the WHO criterion for the primary dentition were 63.0% and 65.9%, respectively, and for the permanent dentition they were 12.7% and 12.8%, respectively.ConclusionsThe CAST instrument provided similar prevalence of dental caries values and dmf/DMF counts as the WHO criterion in this age group. Time spent on examining children was identical for both caries assessment methods. Presentation of results from use of the CAST instrument, in comparison to WHO criterion, allowed a more detailed reporting of stages of dental caries, which will be useful for oral health planners.