Hospital lung cancer surgery volume is not correlated with lower mortality
Research Activities, December 2011, No. 376
Studies correlating higher hospital lung surgery volume with significantly lower mortality risk have suffered from serious methodological limitations, assert the authors of a new study. They found that higher lung cancer surgery volume is not a predictor of lower mortality and should not be used as a proxy measure for hospital surgical quality. Benjamin Kozower, M.D., and George Stukenborg, Ph.D., of the University of Virginia, examined the outcomes of more than 40,000 lung cancer surgery patients. They found that the most important predictors of mortality following lung cancer resection were a patient's age and coexisting diseases.
The new study described three different methods for measuring lung cancer resection volume and evaluated how the manner in which volume was measured affected the significance of the relationship between hospital procedure volume and mortality after lung cancer resection.
One of the problems with earlier studies was that procedure volumes were placed into arbitrarily defined categories rather than treating volume as a continuous variable. Another problem was that the quality and performance of the statistical models used and the contribution of procedure volume to explained variance were not rigorously evaluated.
The researchers concluded that the impact of procedure volume on mortality is dependent on how the volume variable is defined and entered into the regression equation. They call for more research to determine the strength and validity of the volume-outcome relationship. This study was supported by the Agency for Healthcare Research and Quality (HS18049, HS17693).
See "The relationship between hospital lung cancer resection volume and patient mortality risk," by Drs. Kozower and Stukenborg, in the May 2011 Annals of Surgery, pp. 1528-1540.