Re:statistics (Score 1)

From your description, I believe that 9.6 and 8.5 are not standard errors (numbers used to evaluate the uncertainty associated with the sample mean) but are standard deviations (numbers used to evaluate the spread of a population). Therefore to make the kind of comparison you're trying to do you would have to divide 9.6 and 8.5 by the square roots of the respective sample sizes. The confusion comes about because, for some reason, it has become a convention to report "mean +/- sd" in the medical literature where the "+/-" which doesn't make a lot of sense. Reporting "mean +/- std. error" would at least be a 68% confidence interval. I think that it would be better if people simply reported (mean, sd, n), that way people would have all of the relevant info.