A simple, reliable, and validated method for measuring brow position.

Abstract

To establish outcome of brow suspension techniques, a reliable and clinically suitable measurement tool is required. Most of the published methods lack statistical validation, and in none of the reviewed studies, the standardized photograph protocols were validated. Fifteen subjects were independently photographed by 2 different professional medical photographers. Adobe Photoshop CS5 software (San Jose, Calif) was used to perform the measurements based on interpupillary distance and medial, midpupil, and lateral reference points on the brow. To establish intrarater reliability, the photos of both photographers of the same subject were analyzed by the same researcher. To establish interrater reliability, the photos of 1 photographer were analyzed by 1 researcher, whereas the photos of the second photographer were analyzed by a second researcher. Reliability was assessed using the intraclass correlation coefficients (ICCs) and the smallest detectable differences. The ICCs indicated good to excellent interrater and intrarater reliability. The ICCs of the interrater reliability were lower compared with those of the intrarater reliability, although they could still be categorized as good to excellent. We found that the lateral measurements had the highest reliability, and the medial measurements, the lowest reliability. The current study supports that the "en face" photographs in our database are truly standardized. The good to excellent interrater and intrarater reliability of the present method makes it a valid measuring tool.