GM Junior India, 20171030 06:22 Posting: # 17944 Views: 602 

Hello all, I need help regarding In Vitro Release Testing of semisolid dosage forms. Here is the guidance given by the FDA in page 22 of 40. In Vitro Release Testing  FDA My doubt is, How the 90% confidence Intervals are calculated..? I was tried with "MannWhitney Median Confidence Interval with HodgesLehmann estimation" using below formula. 90% CI= mn/2 ± Zcrit*(sqrt((mn*(m+n+1))/12) Lower limits are matching with guidance but not upper limits with only one digit difference. Here is my calculation for 6Runs, 2Runs and 2Runs with one cell missing. m 18 6 5 Edit: Tabulators changed to spaces and BBcoded; see also this post #6. URL corrected. Please don’t link to a GoogleIndia search term. [Helmut] 
GM Junior India, 20171101 06:51 @ GM Posting: # 17960 Views: 499 

Hello all, Any idea for the above topic.Kindly let me know. How to calculate the 90% CI for the median using Wilcoxon Rank Sum/MannWhitney rank test...? Thanks in advance, GM. Edit: Relax; see also this post #8. [Helmut] 
zizou Junior Plzeň, Czech Republic, 20171101 19:49 (edited by zizou on 20171101 20:03) @ GM Posting: # 17961 Views: 447 

Dear GM. First of all, I figured out your link to the reference: https://www.fda.gov/downloads/drugs/guidances/ucm070930.pdf Example from page 23 (PDF page 26 of 40). Lower limit is the 8^{th} value of sorted values and upper limit is 29^{th} value as mentioned in the text (PDF page 27 of 40). 8 is 5^{th} quantile calculated from the equation as you already mentioned: w(0.05) = mn/2  z_{crit}*sqrt(mn*(m+n+1)/12) ... approximation for m+n large enough. And 29 is 95^{th} quantile + 1. Here you probably forgot "+ 1" to get the right position of upper limit. In this case there is even count of ordered data. Lower limit is 8^{th} from the start, upper limit is 8^{th} from the end, i.e. 29^{th} from the start. So you get the positions of ordered data and then you have lower and upper limit directly, you know. Best regards, zizou 
Helmut Hero Vienna, Austria, 20171101 23:07 @ zizou Posting: # 17962 Views: 399 

Hi Václav and GM, see also this rather old post with tables of the positions of the lower critical values and exact probabilities for m=n=3–32. Generally the normal approximation should not be used if m <8 or n <8. — Regards, Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. ☼ Science Quotes 
GM Junior India, 20171102 06:21 @ Helmut Posting: # 17963 Views: 364 

Dear Zizou and Helmut, Thank you so much for the response. This is really helped me alot. Thank you, GM. 