RT Journal Article SR Electronic T1 Review of concentration yields in commercially available platelet-rich plasma (PRP) systems: a call for PRP standardization JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 652 OP 659 DO 10.1136/rapm-2018-100356 VO 44 IS 6 A1 Priyal P Fadadu A1 Anthony J Mazzola A1 Corey W Hunter A1 Timothy T Davis YR 2019 UL http://rapm.bmj.com/content/44/6/652.abstract AB Platelet-rich plasma (PRP) has become increasingly popular in pain medicine with hopes of becoming a safe, effective alternative to routine treatments. However, given its autologous nature, PRP injectate may differ depending on the specific manufacturer and protocol. Currently, there is no standardization of reporting protocol. This systematic review compiles and standardizes values on PRP preparation and final product composition of platelets, white cell count, and growth factors for ease of comparison. On review of 876 studies, 13 studies were selected according to our inclusion criteria. Data from 33 PRP systems and protocols were extracted and standardized. Overall, PRP final product concentrations as well as PRP preparation protocols varied widely between systems. However, platelet concentration was directly correlated with both volume of blood collected and device centrifugal force. In conclusion, there is a large heterogeneity between PRP separation systems that must be resolved for proper study of this promising treatment.