90% confidence interval for R_dnm [Study Assessment]
Happy New Year!
❝ Late but hopefully not too late insight. As I sometimes stated: All answers (of asked or not asked questions) are here. You only have to dig out what you are interested in.
Reproduce Smith's results in SAS is easy enough (except the 90% CI of Rdnm, which is not realy need for judging dose proportionality), but I struggled for a loooooong loooooooooong time with R as I was playing
lm
and glm
and to make it worse, random effect was coded wrong.... Obviously, my R skill needs to be improved much more 
Anyway, not too late for me. I'll check the R code mentioned by Zizou and Helmut et al later.
❝ Can you please elaborate where your difficulties arose? Able to obtain a point estimate of Rdnm but no 90% CI thereof?
yes.
❝ I would go with the formula of Rdnm
❝
R_dnm = r^(beta1 - 1)
❝ with r= ratio of highest to lowest dose and beta1=slope
❝ Use this with the point estimate of beta1 from your model and its 90% CI limits and you obtain the 90% CI of Rdnm if I'm correct.
❝ R console:
❝ c(10^(0.7615-1), 10^(0.679-1), 10^(0.844-1))
❝ [1] 0.5774309 0.4775293 0.6982324
❝ Smith reported in Table 2:
❝ 0.577 (0.477, 0.698)
❝ Good enough?
This must be it!
According to his article, Smith use the formula EXP(beta0 + beta1*ln(dose)) to calculate each mean to get ratio Rdnm. so the value is Rdnm = 0.577402 (red digit from my sas). But this is equivalent to what you wrote so if you use the full precision figure we would have obtained the same values (90% CI of (0.477381, 0.698378)). I checked with the AUC data as well, they matches what's reported in table 2.
❝ Hope this helps.
All the best,
Shuanghe
Complete thread:
- Dose Proportionality and Variance AngusMcLean 2016-05-11 16:55 [Study Assessment]
- More information, please Helmut 2016-05-12 14:34
- More information, please AngusMcLean 2016-05-13 16:40
- Setup in Phoenix/WinNonlin Helmut 2016-05-14 02:26
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-14 18:54
- Setup in Phoenix/WinNonlin Helmut 2016-05-15 14:47
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-15 15:17
- Phoenix 64 Warning Helmut 2016-05-15 15:56
- Phoenix 64 Warning AngusMcLean 2016-05-15 20:11
- OT: imperial vs. metric units Helmut 2016-05-16 16:26
- Phoenix 64 Warning AngusMcLean 2016-05-15 20:11
- Setup in Phoenix/WinNonlin ElMaestro 2016-05-15 20:54
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-15 22:30
- Phoenix 64 Warning Helmut 2016-05-15 15:56
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-15 15:17
- Setup in Phoenix/WinNonlin Helmut 2016-05-15 14:47
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-16 21:00
- NCSS vs. PHX/WNL vs. SAS Helmut 2016-05-17 01:50
- NCSS vs. PHX/WNL vs. SAS - Validation? mittyri 2016-05-18 08:23
- Diagnostics ElMaestro 2016-05-18 09:20
- Diagnostics: R and Phoenix Helmut 2016-05-18 15:14
- Diagnostics: R zizou 2016-05-22 19:07
- Diagnostics: R Helmut 2016-05-23 01:22
- SASian potpourri d_labes 2016-05-24 12:02
- Compilation Helmut 2016-05-24 14:27
- REML or not d_labes 2016-05-24 16:33
- complete or not Helmut 2016-05-24 16:57
- Compilation AngusMcLean 2016-05-26 16:46
- doubts about NCSS Helmut 2016-05-26 19:13
- Doubts about NCSS zizou 2016-05-26 23:38
- doubts about NCSS Helmut 2016-05-26 19:13
- Compilation AngusMcLean 2016-05-28 00:51
- Kenward-Roger? Helmut 2016-05-28 15:59
- 90% confidence interval for R_dnm Shuanghe 2019-01-04 17:45
- 90% confidence interval for R_dnm d_labes 2019-01-05 14:01
- Visualizing lmer and limits mittyri 2019-01-06 17:00
- Visualizing lmer and limits Shuanghe 2019-01-07 11:05
- Visualizing lmer and limits d_labes 2019-01-07 15:08
- Visualizing lmer and limits mittyri 2019-01-13 23:53
- 90% confidence interval for R_dnmShuanghe 2019-01-07 10:53
- 90% confidence interval for R_dnm d_labes 2019-01-07 15:17
- 90% confidence interval for R_dnm Shuanghe 2019-01-07 17:11
- 90% confidence interval for R_dnm d_labes 2019-01-07 18:24
- offtop: greek letters and tables mittyri 2019-01-08 00:19
- OT: greek letters and symbols Helmut 2019-02-02 16:04
- 90% confidence interval for R_dnm Shuanghe 2019-01-07 17:11
- 90% confidence interval for R_dnm d_labes 2019-01-07 15:17
- Visualizing lmer and limits mittyri 2019-01-06 17:00
- 90% confidence interval for R_dnm d_labes 2019-01-05 14:01
- REML or not d_labes 2016-05-24 16:33
- Compilation Helmut 2016-05-24 14:27
- SASian potpourri d_labes 2016-05-24 12:02
- Diagnostics: R Helmut 2016-05-23 01:22
- Diagnostics: R zizou 2016-05-22 19:07
- Diagnostics: R and Phoenix Helmut 2016-05-18 15:14
- Smith’s paper Helmut 2016-05-18 14:44
- Smith’s paper d_labes 2019-01-05 15:00
- Diagnostics ElMaestro 2016-05-18 09:20
- NCSS vs. PHX/WNL vs. SAS - Validation? mittyri 2016-05-18 08:23
- NCSS vs. PHX/WNL vs. SAS Helmut 2016-05-17 01:50
- Setup in Phoenix/WinNonlin AngusMcLean 2016-05-14 18:54
- Setup in Phoenix/WinNonlin Helmut 2016-05-14 02:26
- More information, please AngusMcLean 2016-05-13 16:40
- More information, please Helmut 2016-05-12 14:34