This is the peer reviewed version of the following article: Agha, B. and Johal, A. (2017), Facial phenotype in obstructive sleep apnea–hypopnea syndrome: a systematic review and meta-analysis. J Sleep Res, 26: 122–131. doi:10.1111/jsr.12485, which has been published in final form at http://dx.doi.org/10.1111/jsr.12485. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.