2024 Evidence of Coverage for UnitedHealthcare® Group Medicare Advantage PEBB Balance (PPO) Chapter 4: Medical Benefits Chart (what is covered and what you pay) 75 relevant medical community, relying primarily on controlled clinical trials, or, if not available, observational studies from more than one institution that suggest a causal relationship between the service or treatment and health outcomes. If no credible scientific evidence is available, then standards that are based on Physician specialty society recommendations or professional standards of care may be considered. We reserve the right to consult expert opinion in determining whether health care services are Medically Necessary. The decision to apply Physician specialty society recommendations, the choice of expert and the determination of when to use any such expert opinion, shall be within our sole discretion.