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Researcher101 ☆ Egypt, 2020-10-10 21:27 (971 d 22:12 ago) Posting: # 21987 Views: 1,863 |
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Dear All, I wanna know what exactly the randomization sequences if I will go for fully replicate ( Four periods) with three arms/treatments ( T1, T2, R) If i'm going for a four periods of two treatments I will go for TRTR and RTRT so if there are 3 treatments, How many and what are the sequences? Edit: Category changed; see also this post #1. [Helmut] |
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Helmut ★★★   Vienna, Austria, 2020-10-10 22:06 (971 d 21:33 ago) @ Researcher101 Posting: # 21988 Views: 1,574 |
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Hi Researcher101, ❝ Dear All, I wanna know what exactly the randomization sequences if I will go for fully replicate ( Four periods) with three arms/treatments ( T1, T2, R) You need four sequences. \(\small{\begin{array}{ccccc} For the evaluation exclude either \(\small{\text{T}_2}\) or \(\small{\text{T}_1}\) to obtain two partial replicate designs with missing (\(\small{\bullet}\)) observations. \(\small{\begin{array}{ccccc} \(\small{\begin{array}{ccccc} — Dif-tor heh smusma 🖖🏼 Довге життя Україна! ![[image]](https://static.bebac.at/pics/Blue_and_yellow_ribbon_UA.png) Helmut Schütz ![[image]](https://static.bebac.at/img/CC by.png) The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes |
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ElMaestro ★★★ Denmark, 2020-10-10 22:53 (971 d 20:46 ago) @ Helmut Posting: # 21989 Views: 1,549 |
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Hi, wise words from Helmut. ❝ For the evaluation exclude either \(\small{\text{T}_2}\) or \(\small{\text{T}_1}\) to obtain two partial replicate designs with missing (\(\small{\bullet}\)) observations (...) ...and depending on the context this could be a case where alpha adjustment is appropriate (if you are claiming BE if either T1 or T2 show BE, but the devil is in the details as they say). — Pass or fail! ElMaestro |
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Helmut ★★★ Vienna, Austria, 2020-10-10 23:18 (971 d 20:21 ago) @ ElMaestro Posting: # 21990 Views: 1,534 |
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Hi ElMaestro, ❝ ...and depending on the context this could be a case where alpha adjustment is appropriate (if you are claiming BE if either T1 or T2 show BE, but the devil is in the details as they say). Heck, you were faster than I! I just wanted to edit my post to add my usual question: What do you want to achieve? @ Researcher101: See this presentation (slides 22–23). — Dif-tor heh smusma 🖖🏼 Довге життя Україна! Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes |
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Researcher101 ☆ Egypt, 2020-10-11 11:07 (971 d 08:32 ago) @ Helmut Posting: # 21991 Views: 1,514 |
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Thank you so much, but what if I wanna dose the participant T1 twice, T2 twice, R Twice as the drug is highly variable? The main goal is to check which formula ( T1 or T2 ) is more comparable to the reference drug Edit: Full quote removed. Please delete everything from the text of the original poster which is not necessary in understanding your answer; see also this post #5! [Helmut] |
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Helmut ★★★ Vienna, Austria, 2020-10-11 12:57 (971 d 06:42 ago) @ Researcher101 Posting: # 21992 Views: 1,520 |
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Hi Researcher101, ❝ […] I wanna dose the participant T1 twice, T2 twice, R Twice as the drug is highly variable? ❝ The main goal is to check which formula ( T1 or T2 ) is more comparable to the reference drug OK, you are planning a pilot study. With six periods you are draining volunteers (hope your bioanalytical method can deal with small sample volumes). Dropouts are also an issue. I have never seen a study with more than five periods so far. I tried to find a balanced incomplete block design (with less than six periods) to no avail… Since you mentioned a Williams’ design in your original post: No idea. One option would be a Latin Square: \(\small{\begin{array}{ccccccc} Exclusions as usual: \(\small{\begin{array}{ccccccc} Select the test with a PE closer to 100% (i.e., \(\small{\textrm{min}\left\{\left|\log_{e}\text{T}_1/\text{R} \right|,\left|\log_{e}\text{T}_2/\text{R} \right|\right\}}\)) for the pivotal study. If PEs are similar – don’t ask me what “similar” is – opt for the one with lower CVwT. — Dif-tor heh smusma 🖖🏼 Довге життя Україна! Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes |
Ing. Helmut Schütz