A new index for assessing surgical outcome in unilateral cleft lip and palate subjects aged five: reproducibility and validity.

OBJECTIVE This study assessed the reproducibility, reliability, and predictive validity of a previously developed index by the authors for assessing surgical outcome in unilateral cleft lip and palate (UCLP) children aged 5. METHODS Sixty randomly selected study models of 5- to 6-year-old complete UCLP subjects were obtained and the index was used to assess their surgical outcomes. RESULTS Assessment of these study models using the new index demonstrated excellent intra-examiner agreement. The inter-examiner agreement was shown to be good. The corresponding longitudinal models at 16 to 18 years of 54 of the initial 5- to 6-year-old sample were also acquired. These subjects had undergone orthodontic treatment but not orthognathic surgery. The need for osteotomy amongst these models was assessed. Between 13% and 18% (depending on examiner) of 5-year-olds' models were scored in the groups likely to require orthognathic surgery. In the corresponding 16- to 18-year-olds' models, 9% were assessed as likely to benefit from an osteotomy. However, on an individual basis, it was not possible to predict future growth from study models at age 5. CONCLUSIONS This study has provided a reliable and reproducible index for assessing the outcome of surgery in UCLP subjects earlier than indices already available. True validation of the index was not possible but it appears that it relies on face validity.