Preparation methods and clinical outcomes of platelet-rich plasma for intra-articular hip disorders: a systematic review and meta-analysis of randomized clinical trials - Garcia, Flávio Luis; Williams, Brady T.; Polce, Evan M.; Heller, Daniel B.; Aman, Zachary S.; Nwachukwu, Benedict U.; Nho, Shane J.; Chahla, Jorge (Orthopaedic Journal of Sports Medicine, 2020)