Reliability assessment and validation of the postacne hyperpigmentation index (PAHPI), a new instrument to measure postinflammatory hyperpigmentation from acne vulgaris

Stephanie A. Savory, Nnenna G. Agim, Rui Mao, Shayna Peter, Casey Wang, Gerardo Maldonado, Jessica Bearden Dietert, Tiffany Jane Lieu, Christy Wang, Kara Pretzlaff, Shinjita Das, Travis Vandergriff, Isha E. Lopez, Brandon R. Litzner, Linda S. Hynan, Maria Ivonne Arellano-Mendoza, Paul R. Bergstresser, Amit G. Pandya