Lee KC, et al. - In order to support the efforts to integrate palliative care (PC) alongside restorative surgical care for seriously ill surgical patients, researchers developed a serious illness definition for these patients and sought for a denominator for quality measurement efforts. A set of criteria for 11 conditions and health states were included in the preliminary definition. Employing the RAND-UCLA Appropriateness Method, a 12-member expert advisory panel evaluated the criteria for each condition and health state twice, once following an in-person moderated discussion, for validity (primary outcome) and feasibility of measurement. Both rounds of rating were completed by all panelists. They rated all 11 conditions and health states defining serious illness for surgical patients as valid. After refinement and narrowing of criteria for two conditions (vulnerable elder, heart failure), the panelist included following 11 conditions and health states in the final definition: vulnerable elder, heart failure, advanced cancer, oxygen-dependent pulmonary disease, cirrhosis, end-stage renal disease, dementia, critical trauma, frailty, nursing home residency, and American Society of Anesthesiology Risk Score IV-V.