Modified IOTN: an orthodontic treatment need index for use in oral health surveys

This paper reports the results of a study of the reliability of a modified version of the Index of Orthodontic Treatment Need (IOTN) for use in oral h ealth surveys. Twelve non-specialist dental examiners were trained in the u se of the Modified IOTN using a standardised teaching protocol lasting appr oximately 1.5 hours. Following a school-based calibration exercise it was f ound that nearly all the examiners achieved either good or excellent agreem ent (mean Kappa=0.74). The average sensitivity and specificity scores were 0.90 and 0.84, respectively. The Modified IOTN appears to overcome the trai ning and reliability problems that often accompany the use of orthodontic i ndices by non-specialists in oral health surveys.