ACS: Surveillance Bias Noted in VTE Measurement
(HealthDay News) – Venous thromboembolism (VTE) prophylaxis rates are higher but risk-adjusted VTE rates are worse for hospitals with higher quality scores, according to a study published online Oct. 7 in the Journal of the American Medical Association to coincide with presentation at the annual meeting of the American College of Surgeons, held from Oct. 6–10 in Washington, DC.
Karl Y. Bilimoria, MD, from Northwestern University in Chicago, and colleagues examined whether a surveillance bias influences the validity of reported VTE rates using 2010 Hospital Compare and American Hospital Association merged data from 2,838 hospitals. VTE imaging and event rates were calculated using 2009–2010 Medicare claims data for 954,926 surgical patient discharges from 2,786 hospitals.
The researchers observed a weak correlation between greater hospital VTE prophylaxis adherence rates with worse risk-adjusted VTE event rates. Higher VTE prophylaxis adherence rates were seen for hospitals with increasing structural quality scores, but risk-adjusted VTE rates were significantly worse. From the lowest to the highest imaging use quartile, the mean VTE diagnostic imaging rates ranged from 32–167 studies per 1,000. There was a significant increase in risk-adjusted VTE rates with VTE imaging use in a step-wise manner.
"Although there is considerable attention given to measuring and improving hospital VTE rates, our findings suggest that a surveillance bias influences the validity of VTE measurement," the authors write.
One author disclosed financial ties to the pharmaceutical industry and a second reported giving expert witness testimony in medical malpractice cases.