Background: Few scales are currently available to evaluate changes in hand volume. We aimed to develop a hand grading scale for quantitative assessments of dorsal hand volume with additional consideration of changes in skin texture; to validate and prove the precision and reproducibility of the new scale; and to demonstrate the presence of clinically significant differences between grades on the scale.
Methods: Five experienced plastic surgeons developed the Hand Volume Rating Scale (HVRS) and rated 91 images. Another five plastic surgeons validated the scale using 50 randomly selected images. Intra- and inter-rater agreement was calculated using the weighted kappa statistic and intraclass correlation coefficients (ICCs). Paired images were also evaluated to verify whether the scale reflected clinical differences.
Results: The intra-rater agreement was 0.95 (95% confidence interval, 0.922-0.974). The interrater ICCs were excellent (first rating, 0.94; second rating, 0.94). Image pairs that differed by 1, 2, and 3 grades were considered to contain clinically relevant differences in 80%, 100%, and 100% of cases, respectively, while 84% of image pairs of the same grade were found not to show clinically relevant differences. This confirmed that the scale of the HVRS corresponded to clinically relevant distinctions.
Conclusions: The scale was proven to be precise, reproducible, and reflective of clinical differences.
Keywords: Asian continental ancestry group; Back; Hand; Rejuvenation; Skin aging.