Comparison of the Generic and Condition-Specific Forms of the Oral Impacts on Daily Performances (OIDP) Index

Objective: This study aimed to compare generic and condition-specific forms of the Oral Impacts on Daily Performances (OIDP) in terms of their ability to discriminate between adolescents with and without normative need for orthodontic treatment. Methods: A total of 1,060 15- to 16-year-old adolescents without history of previous or current orthodontic treatment were randomly selected from all secondary schools in Bauru, Brazil. Adolescents were clinically examined by using the Dental Aesthetic Index (DAI). Normative need for orthodontic treatment was defined by using three different suggested cutoff values on DAI score; 28, 31, and 36 points. Two different estimates (overall score and prevalence of oral impacts) were calculated by using the generic and the condition-specific OIDP (CS-OIDP) attributed to malocclusion. Discriminative ability was assessed, comparing both estimates between groups. Effect size and adjusted odds ratios were used to interpret the magnitude and meaning of differences. Results: The overall score and prevalence of oral impacts on quality of life in the last 6 months were significantly lower for the CS-OIDP attributed to malocclusion than for the generic OIDP ( P   <  0.001 in both cases). However, effect sizes and adjusted odds ratios were always larger for the CS-OIDP attributed to malocclusion than for the generic OIDP. Conclusions: Although generic and condition-specific OIDP forms were able to discriminate adolescents with normative need for orthodontic treatment from those without such a need, CS-OIDP attributed to malocclusion had better ability to distinguish between groups. Further studies are needed to compare discriminative ability of both OIDP forms between groups with different levels of other oral conditions .