1.1 This guide is intended as a resource for individuals and organizations involved in designing clinical trials of hip replacement systems (HRSs) including metal/polymer, metal/ metal, metal/composite, metal/ceramic/polymer, metal/ polymer/metal, and ceramic/ceramic bearing surfaces; semiconstrained and constrained designs; and cemented, nonporous uncemented, and porous-coated uncemented fixation. 1.2 In this guide, methods to measure the efficacy, effectiveness, and safety of HRS devices through standardizing outcomes measures are provided for designing, reviewing, and accepting human clinical trial protocols. 1.3 This guide is intended to provide consistency in study design, review, regulatory approval, and coverage approval for hip replacement systems to the health care market. 1.4 For the purpose of this guide, an HRS is any device that is intended to replace the hip joint, in part or in total, as a treatment for joint disease, trauma, or dysfunction, where long-term functional restoration and pain relief without major adverse events are the desired outcomes. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.