; and (II) in the case of potentially-avoidable readmissions, a comprehensive identification of all initial discharges described in paragraph (5)(B) and corresponding readmissions described in such paragraph that each meet the requirements for such readmission to be included as a potentially-avoidable readmission. (ii) To the extent possible, the methodology shall be a methodology that has been successfully implemented for the purpose of adjusting payments to hospitals by a State plan under title XIX or by a major commercial payer or be a methodology that has been certified by an entity with a contract under section 1890(a). (iii) The methodology shall be open, transparent, and available for review and comment by the public. (iv) The Secretary may select proprietary methodologies that meet the criteria in clauses (i) through (iii). (B) Selection criteria for method of risk adjustment For purposes of paragraph (4), the Secretary shall, with respect to each category described in a subparagraph of paragraph (5), select a methodology for specifying risk categories and for assigning individuals entitled to benefits under part A to such categories, and shall so specify such risk categories and so assign such individuals to such categories. Each such methodology shall meet the following criteria: (i) The methodology shall result in an exhaustive and mutually exclusive list of risk categories. (ii) The methodology shall be clinically credible and explicitly account for the severity of illness, chronic illness burden, and extensive comorbid diseases and high severity of illness of patients. (iii) The methodology shall account for patient characteristics that may impact access to care. (iv) The methodology shall assign a risk category to an individual based on the condition of the individual at the time of— (I) in the case of potentially-avoidable complications, hospital admission