Development and validation of a global photonumeric scale for evaluating skin quality of aged female facial skin

Skin quality plays an important role in overall attractiveness. However, so far, no visual grading scales have been published while their development seems to be an essential key step to provide validated grading scales for the evaluation of efficacy of minimally invasive procedures and cosmeceuticals aims on the improvement of skin quality, esthetic research, and clinical application.To develop and validate a visual five-point assessment scale for the evaluation of skin quality of female facial skin.The five-point photonumeric Scientific Assessment Scale of Skin Quality is based on six parameters. Fifty standardized photos were rated by 13 experts. This examination was carried out in two cycles with an interval of 4 weeks. The intraclass correlation coefficient contributes to the identification of the inter-rater and intrarater reliability.Statistical analysis investigated six specific and two general parameters: The results of inter- and intrarater reliability for skin elasticity (ICC 0.816; ICC 0.883), wrinkles (ICC 0.840; 0.885), and age (ICC 0.885; 0.925) were almost perfect. The reliabilities for pigmentation (ICC 0.637; ICC 0.797), erythema (ICC 0.688; ICC 0.797), and overall skin quality (ICC 0.652; ICC 0.756) were substantial and for pore size moderate (ICC 0.405; ICC 0.584). Skin surface roughness (ICC 0.480; ICC 0.645) indicated a substantial intrarater reliability and a moderate interrater reliability. These data revealed good and excellent results.The Scientific Assessment Scale of Skin Quality represents an innovative universal and reliable measurement instrument for a valid and reproducible evaluation of six parameters of aged female facial skin quality.