title: Impact of screening versus symptomatic measurement of deep vein thrombosis in a national quality improvement registry.
abstract: BACKGROUND
  Deep vein thrombosis (DVT) is a quality measure recorded by initiatives such as the National Surgical Quality Improvement Program (NSQIP). However, because surveillance-detected DVT rates may be higher than symptomatic DVT rates, we examined how differences in the method of DVT detection may affect the use of this quality measure.
  
  
  METHODS
  Using the NSQIP database (2007-2009), we compared DVT rates of vascular (amputation, open aortic procedures, and lower extremity bypass) and nonvascular (prostatectomy, gastric bypass [GBP], and hip arthroplasty) operations. Using a predefined literature search strategy, we compared the incidence of DVT in NSQIP to the incidence of DVT reported in published literature, diagnosed by symptomatic status or by surveillance studies.
  
  
  RESULTS
  Within NSQIP, the overall incidence of postoperative DVT was 0.7%. This varied from 0.3% after GBP to 1.8% after open aortic surgery. Across all procedures except amputation, the incidence of DVT in NSQIP was similar to the incidence of DVT reported in our literature survey of "symptomatic" DVTs. The relative rate (RR) of literature-derived symptomatic DVTs to NSQIP ranged from 0.7 for aortic cases (95% confidence interval [CI], 0.3-1.7) to 1.4 (95% CI, .7-3.1) for GBP. Overall, surveillance studies had 11.6 higher RR of DVT compared to NSQIP (95% CI, 10.5-13), ranging from 2.6 for GBP (95% CI, 1.4-5) to 14 .5 for hip arthroplasty (95% CI, 10.5-20).
  
  
  CONCLUSIONS
  The incidence of DVT reported in NSQIP is similar to the reported incidence of symptomatic DVT for many high-risk procedures but is much lower than rates of DVT reported in surveillance studies. Clear delineation of symptomatic vs surveillance detection of DVT would improve the usefulness of this measurement in quality improvement registries.
authors: Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA. randall.r.de.martino@hitchcock.org
authors: Randall R
authors: RR
authors: De Martino
authors: Adam W
authors: AW
authors: Beck
authors: Matthew S
authors: MS
authors: Edwards
authors: Matthew A
authors: MA
authors: Corriere
authors: Jessica B
authors: JB
authors: Wallaert
authors: David H
authors: DH
authors: Stone
authors: Jack L
authors: JL
authors: Cronenwett
authors: Philip P
authors: PP
authors: Goodney
mesh_terms: D000328:Adult; D015331:Cohort Studies; D006801:Humans; D015994:Incidence; D008403:Mass Screening; D011159:Population Surveillance; D011183:Postoperative Complications; D058996:Quality Improvement; D012042:Registries; D015203:Reproducibility of Results; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D020246:Venous Thrombosis / Q000150:complications* / Q000175:diagnosis* / Q000453:epidemiology