"It has long been an axiom of mine that the little things are infinitely the most important" (Sherlock Holmes)

Just a note

k = W_{(α/2)} − [n_{A} (n_{A} − 1)] / 2
where:

k is the required number of differences from each end of the array to obtain the upper and lower confidence limits,

W(α/2) is the quantile of the Wilcoxon test statistic for N_{A} and N_{B} observations. Hence for a 95% confidence interval, look up W in Table A7 in Conover for 8 and 17 observations at P = 0.025.

n_{A} and n_{B} are the number of observations in groups A and B respectively.