Validated 5-point photonumeric scales for the assessment of the jowls and chin

The objective of this investigation was to create and to examine the reproducibility and validity of 5-point photonumeric assessment scales that allow objective assessment of chin retrusion and jawline sagging using a digital and a live validation.

Two new 5-point photonumeric scales created to assess chin projection and jawline sagging were validated by 12 experts in a digital validation and by 5 experts in a live validation setting. Intra-rater agreement and inter-rater agreement were assessed.

For the digital validation, an almost perfect intra-rater (Kappa: 0.89 [95% CI: 0.86-0.91]) and almost perfect inter-rater agreement in both sessions (Kappa: 0.80 [95% CI: 0.74-0.86] and 0.80 [95% CI: 0.74-0.86]) was achieved for the Croma Chin Projection Assessment Scale, while intra-rater agreement (Kappa: 0.88 [95% CI: 0.85-0.91]) was almost perfect for the Croma Jawline Sagging Assessment Scale and inter-rater agreement being substantial in the first session (Kappa: 0.76 [95% CI: 0.71-0.81]) and almost perfect in the second session (Kappa: 0.81 [95%CI: 0.76-0.85]). For the live validation, intra-rater agreement was almost perfect for the Croma Chin Projection Assessment Scale (Kappa: 0.82 [95%CI: 0.74-0.90]) and the Croma Jawline Sagging Assessment Scale (Kappa: 0.83 [95%CI: 0.77-0.89]), while inter-rater agreement was substantial in both sessions for both scales.

The created chin and jawline photonumeric grading scales are valid and reliable tools for assessing chin projection and jawline sagging. The scales will be of value for standardized chin evaluation and quantifying outcomes in clinical research and daily practice.