Bioequivalence and Bioavailability Forum

Blind 2Stage and an elephant [Two-Stage / GS Designs]

posted by Astea – Russia, 2019-05-31 16:36 (2213 d 15:59 ago) – Posting: # 20308
Views: 9,129
(edited on 2019-05-31 22:51)

Dear Helmut!

Thank you for pointing on the article! I've tried to draw a graph similar to Figure 1 of Golkowski et al. by using power.tsd.ssr. It uses CV instead of N of the second size, but the tendency is pretty similar: low sample size of the first stage can significantly enlarge the TIE.

❝ Simulations… Might be tricky cause we have to think about unequal group sizes and/or variances.

Is it possible to do it with Power2Stage or some modifications? (As I understand power.tsd.p deals with unblind scheme?) The co-authors of the aforementioned article have also an article dedicated to the parlallel groups but relatively to non-inferiority trials...

Complete thread:

• 2-stage design with interim sample size estimation d_labes 2010-10-05 15:09 
  • 2-stage design with interim sample size estimation Jack 2010-10-25 18:20
    • Null = bioINequivalence Helmut 2010-10-25 19:16
    • 2-stage design with interim sample size estimation d_labes 2010-10-26 13:28
      • 2-stage design with interim sample size estimation Jack 2010-10-26 18:26
        • Blind or not, Indecisions or Decisions d_labes 2010-10-27 16:01
          • Blind or not, Indecisions or Decisions Jack 2010-10-27 18:14
            • Blind ? Ohlbe 2010-10-27 23:37
              • Blind ? Jack 2010-10-28 10:24
                • Blind 2Stage Astea 2019-05-30 10:37
                  • Blind 2Stage Helmut 2019-05-30 12:56
                    • Blind 2Stage and an elephantAstea 2019-05-31 14:36
                      • Which elephant? Helmut 2019-06-02 20:14
                        • Blind interim in parallel design? Astea 2019-06-03 01:47
                          • Blind men d_labes 2019-06-05 12:23
                            • The Blind Leading the Blind Astea 2019-06-06 00:55