Comparison of the discriminative ability of the generic and condition-specific forms of the Child-OIDP index: a study on children with different types of normative dental treatment needs

To compare the discriminative ability of the Generic and Condition-Specific forms of the Child-OIDP index on groups defined by their normative treatment need for dental caries, periodontal disease, malocclusion and traumatic dental injuries. All 1034 11-12-year-old children were included from all the primary schools in a municipal area of Suphanburi Province, Thailand. Children were interviewed about sociodental impacts on quality of life in the past 3 months using the Child-OIDP index, and then clinically examined to assess their normative treatment need for dental caries, periodontal disease, malocclusion and traumatic dental injuries. Discriminative ability of the Generic and the Condition-Specific Child-OIDP (CS-Child-OIDP) was assessed through differences in overall scores and prevalences of oral impacts between groups, as well as through their respective effect sizes and adjusted Odds Ratios (ORs). Differences in overall scores and prevalences of oral impacts between groups with and without each of the four types of normative dental treatment needs, their corresponding effect sizes and adjusted ORs, were always significant for CS-Child-OIDP. However, when the Generic Child-OIDP was used to discriminate between groups, the respective figures were significant only for groups with and without normative treatment need for dental caries. CS-Child-OIDP was better able to discriminate between groups with and without each of the four types of normative dental treatment need. The better performance of CS-Child-OIDP compared with the generic Child-OIDP was independent of the indicator used to assess discriminative ability (i.e. differences between groups, effect sizes or adjusted ORs).