Table 1.

Prior Literature Overview for ASA Class Utility in ASD Surgery.

Authors	Year	Data Source	Sample Size	ASA Class Analyzed	Major Findings
Pateder et al17	2008	Single-center, chart review	361	Yes	ASA + for short-term mortality
Schwab et al14	2012	Multicenter, chart review	953 (150 used)	Yes	ASA not correlated with postoperative complications
Tang et al7 ,a	2014	Single-center, chart review	236	Yes	ASA + for major postoperative complications (OR = 2.21)
Smith et al16	2016	Multicenter, prospective	291	No	Comorbidities, age, and obesity associated with complications
Manoharan et al28	2016	Multicenter, database	747	No	Preoperative risk factors associated with 30-day readmissions
This study	2016	Multicenter, database	5822	Yes	ASA + for postoperative morbidity

Abbreviations: ASA, American Society for Anesthesiologists; ASD, adult spinal deformity; OR, odds ratio.

^aEvaluated for lumbar scoliosis surgery only.