A Validated Assessment Scale for Asian Chin Projection

Validation of a Chin Retrusion Scale for Chinese Subjects

ABSTRACT

Chin augmentation procedures are gaining in popularity. The purpose of this study was to validate the China (Allergan) Chin Retrusion Scale (CACRS) and to evaluate the reliability of the scale. A team of 10 physicians based in Beijing, China, consisting of 1 principal investigator and 9 independent raters, assessed a pool of subject images. Using standardized equipment to capture 2-dimensional images, 100 subjects were photographed from a left, lateral, 90° view. Two measures were used to assess the validity of the scale: rater evaluations of clinically significant differences in 52 pairs of images and rater assessment of chin retrusion using the CACRS to grade the 100 images. The CACRS demonstrated almost perfect inter-rater agreement during 2 validation sessions, with intraclass correlation coefficients of 0.89 and 0.90 at sessions 1 and 2, respectively. Overall inter-rater agreement for all 9 raters was almost perfect, with a weighted kappa of 0.82. Based on inter- and intra-rater agreement, the CACRS was validated for physician ratings of chin retrusion in Chinese subjects. Results from clinical significance evaluations indicated that a 1-grade difference between image pairs was considered clinically meaningful for the CACRS. The CACRS is a validated and reliable photonumeric scale for the assessment of chin retrusion in Chinese men and women. The scale is a clinically significant reference tool for evaluating the effect of chin augmentation.

A Validated Grading Scale for Downturned Oral Commisure in Asian Faces

BACKGROUND

Downturned oral commissures develop gradually with aging. Tools have been developed to evaluate the marionette line or the lower face. However, there is no validated and reproducible tool to evaluate the progress after oral commissure treatment in clinical practice.

OBJECTIVE

The authors aimed to develop a scoring system to evaluate therapeutic interventions for downturned oral commissures and to verify its reliability, reproducibility, and clinical significance.

METHODS AND MATERIALS

In the Scale Development Group, the Delphi method was used to establish a 5-graded scoring system to evaluate oral commissure position. The scoring system was applied to 50 participants. The authors recorded and compared the intrarater agreement, interrater agreement, and significance of the grade-dependent scale.

RESULTS

Delphi analysis of the scoring system verified the grade description adequacy. Intrarater agreement showed almost perfect agreement, and the intraclass correlation coefficient of the interrater agreement had a significantly higher agreement rate. The differences between the clinical grades were significant.

CONCLUSION

The Hugel Downturned Oral Commissure Scale is precise, reproducible, and reflective of the clinical differences for downturned oral commissure. Its novelty lies in the use of specific angles and ratio. This scale has clinical trial potential owing to its standardized and quantitative assessment.