The Effect of Landmark Variability on Automated PAP Mask Sizing

We present a study of the effect of variability in manual facial landmarking annotation on image based positive airway pressure mask sizing. Employing 12 expert annotators to identify specific facial landmarks on two images, ANOVA analysis was used to investigate landmark variability attributed to the annotator, types of landmarks and images. We found that while there was agreement between annotators, variance in individual landmark positions resulted in an error of up to 13.59% in measurements defining mask size. A number of different options are presented for reducing errors from manual facial landmarking.