GRAPEVINE, TEX. The outcomes of cosmetic dermatologic procedures are in the eyes of the beholders.
The mindset of expert evaluators and their level of blinding can play critical roles in how the results of a cosmetic procedure are judged, Dr. David Horne said at the annual meeting of the American Society for Laser Medicine and Surgery.
He tested this hypothesis in a "Rashomon"-like study in which the same set of before-and-after clinical images from a noninvasive dermatologic procedure performed on about 10 patients was presented to five different groups of evaluators. In each case, the evaluators reached different conclusions about the treatment's efficacy.
The first group of evaluators comprised enthusiasts for the procedure who were unblinded as to which images were taken before treatment and which were taken after. These experts judged the results as impressive, with all patients having at least 25% improvement, said Dr. Horne of New York-Presbyterian Hospital.
The experts in the second group were ambivalent about the procedure and were unblinded. They rated the images as showing modest benefit, with selected patients getting up to 25% improvement, he said.
The third group included experts who were skeptics of the procedure and were unblinded. They rated the images as showing minimal improvement, with several patients showing no response.
The fourth group was the same set of ambivalent experts as in group 2. They were reshown the images 3 months after their first assessment, but they were completely blinded as to which images were taken before treatment and which were made after treatment and this time they said that most patients were not changed by their treatment, and in some cases the treatment seemed to worsen their appearance.
The fifth group, the patients themselves, said that they all had at least a 20% improvement in appearance, with an average improvement of 50%, said Dr. Horne.