Effect of diagnostic threshold on the validity and reliability of epidemiological caries diagnosis using the Dundee Selectable Threshold Method for caries diagnosis (DSTM)
He. Fyffe et al., Effect of diagnostic threshold on the validity and reliability of epidemiological caries diagnosis using the Dundee Selectable Threshold Method for caries diagnosis (DSTM), COMM DEN OR, 28(1), 2000, pp. 42-51
Objectives: To develop a method for recording dental caries at the D-1 (ena
mel and dentine) diagnostic threshold (without loss of D-3 information) and
assess its reliability, 'benchmark' validity and potential effects on repo
rted caries prevalence and needs assessment. Methods: Multi-examiner traini
ng, calibration and validation trial. Two groups of 10 dental examiners wer
e trained to diagnose dental caries at the D-1 (enamel and dentine) diagnos
tic threshold under the conditions of a caries prevalence survey, prior to
a calibration trial being undertaken. Results: Where 'experienced examiners
' were trained to examine at the D-1 (enamel and dentine) diagnostic thresh
old, under the conditions of a cross-sectional epidemiological survey, ther
e was no significant deterioration in inter-examiner agreement on the asses
sment of teeth and a significant difference in one of two comparisons on th
e assessment of surfaces using the kappa statistic. Assessed against a benc
hmark examiner, there was no significant loss of sensitivity at the D-1 dia
gnostic threshold compared with the D-3 threshold and, although there was a
significant loss of specificity at the D-1 threshold, all specificity valu
es could be considered to be high. Conclusions: Modifying the diagnostic cr
iteria typically used in surveys of caries prevalence (to allow assessment
of the levels of enamel caries which could benefit from preventive care as
well as dentinal caries requiring restorative care) in adolescents does not
adversely affect the reliability or benchmark validity of experienced exam
iners to a significant degree.