Given the aging surgical population, there is increased interest in preoperatively identifying frail patients who may be at risk for adverse postoperative outcomes.1 In 2013, Velanovich et al2 mapped 70 variables contained within the frailty index (FI) proposed by Rockwood et al3 onto data from the 2005-2009 American College of Surgeons National Surgical Improvement Program (ACS-NSQIP) to develop an 11-point modified frailty index (mFI) to identify patients at risk for adverse postoperative outcomes. While the ACS-NSQIP initially mandated the reporting of all variables contained within the mFI, beginning in 2011, the reporting of some preoperative patient comorbidity variables was made optional. In addition, more recent versions of the ACS-NSQIP since 2012 do not record these variables altogether. Despite the change in ACS-NSQIP variables, the mFI continues to be widely used by surgeons and researchers to assess frailty within the ACS-NSQIP database.4- 6 We examined the use of the mFI within the ACS-NSQIP database over time with regard to missing data as well as predictive ability.
Gani F, Canner JK, Pawlik TM. Use of the Modified Frailty Index in the American College of Surgeons National Surgical Improvement Program DatabaseHighlighting the Problem of Missing Data. JAMA Surg. Published online October 26, 2016. doi:10.1001/jamasurg.2016.3479