Archived Comments for:
Intraoperative fluid optimization using stroke volume variation in high risk surgical patients: results of prospective randomized study
While reviewing the literature on fluid responsiveness, including the article by Benes et al. (Critical Care 2010, 14:R118), I was struck by the similarity between the prospectively randomized groups in the demographics table (Table 2). In the words of one of our statisticians, "Of the 22 baseline characteristics presented in Table 2, only three had a p-value that was less than 0.500 The probability of this happening by chance is small (less than 1/1000)". Even a prospectively stratified study (which this was not - it was apparently randomized, not stratified, if I read the Methods correctly) would have difficulty achieving such balance across so many variables simultaneously. Perhaps I have misread the Methods, but I would appreciate clarification of Benes et al.'s randomization procedures.
Critical Care
Request for Clarification of Randomization Method
16 August 2011
Dear Editor,
While reviewing the literature on fluid responsiveness, including the article by Benes et al. (Critical Care 2010, 14:R118), I was struck by the similarity between the prospectively randomized groups in the demographics table (Table 2). In the words of one of our statisticians, "Of the 22 baseline characteristics presented in Table 2, only three had a p-value that was less than 0.500 The probability of this happening by chance is small (less than 1/1000)". Even a prospectively stratified study (which this was not - it was apparently randomized, not stratified, if I read the Methods correctly) would have difficulty achieving such balance across so many variables simultaneously. Perhaps I have misread the Methods, but I would appreciate clarification of Benes et al.'s randomization procedures.
Competing interests
None declared