The Relationship Between the American Society of Anesthesiologists Physical Status Classification and Patient Outcomes: A Scoping Review Protocol

BACKGROUND: The American Society of Anesthesiologists Physical Status (ASA-PS) classification system is ubiquitous in perioperative medicine and research as a tool for preoperative patient risk stratification. Despite widespread clinical adoption as a predictor of perioperative outcomes, the ASA-PS system is inherently subjective, leading to considerable inter-rater variability. A comprehensive mapping of the literature examining the relationship between ASA-PS scores and patient outcomes is lacking. OBJECTIVES: To systematically map the extent, range, and nature of peer-reviewed literature examining the relationship between the ASA-PS classification and patient outcomes, and to identify key characteristics, themes, and knowledge gaps in this evidence base. METHODS: This scoping review will be conducted according to the Joanna Briggs Institute (JBI) methodological framework and reported using the Preferred Reporting Items for Systematic Review and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR). The Population-Concept-Context (PCC) framework will guide eligibility assessment. A comprehensive search will be conducted across PubMed, EMBASE, Scopus, LILACS, and the Cochrane Central Register of Controlled Trials, with no language or date restrictions. Study selection will be performed independently and in duplicate by two reviewers in two stages (title/abstract screening, full-text review). If any discordance appears, a third reviewer verdict will be requested. Data will be extracted using a structured charting form and synthesized narratively. CONTEXT: Any healthcare setting where an ASA-PS score is assigned prior to a procedure (inpatient hospital, ambulatory surgery center, outpatient clinic). Primary research designs, including randomized controlled trials, observational studies (cohort, case-control, cross-sectional, descriptive), and case reports will be eligible; review articles, editorials, letters to the editor, and commentaries will be excluded. SEARCH STRATEGY: The search will employ controlled vocabulary (MeSH terms) and free-text keywords including: "ASA score," "ASA Physical Status Classification System," "American Society of Anesthesiologists," in combination with outcome-related terms. Supplementary hand searching of reference lists and Google Scholar will be performed. DATA EXTRACTION: Study characteristics (author, year, country, journal, design), population characteristics (sample size, age, comorbidity), context (clinical setting, specialty, procedure type, urgency), ASA score details, and outcome details (including statistical methods used to derive associations) will be extracted. A preliminary data charting form is provided in Appendix B. SYNTHESIS: Narrative synthesis supported by descriptive statistics will map study characteristics, outcome categories, clinical contexts, study designs, and temporal and geographical distribution of research. No formal quality appraisal will be conducted. ETHICS AND REGISTRATION: Ethics committee approval is not required for this protocol-based scoping review.