90% confidence interval for R_dnm [Study Assessment]
Dear all,
Man, I should checked here before I started my work. It could save me a lot of time...
Recently I was helping one of my colleagues for dose proportionality study and power model in Smith's article is the preferred method. While I did figured out the "correct" degree of freedom method and reproduce all reported results such as intercept, slope, and 90% CI of those values, ρ1, ρ2, the ratio of dose-normalised geometric mean value Rdnm,..., I could not figure out how Smith obtained the 90% confidence interval for Rdnm (0.477, 0.698).
According to Smith , testing θL < Rdnm < θU to draw conclusion of dose proportionality is equivalent to testing 1 + ln(θL)/ln(r) < β1 < 1 + ln(θH)/ln(r). The latter is what we do and obtaining 90% CI for slope is easy enough and we can judge of dose proportionality based on that. However, it's also interesting to be able to reproduce all Smith's results.
In his article (pp.1282, 2nd paragraph), Smith wrote that "The 90% CI for the difference in log-transformed means was calculated within the MIXED procedure. Exponentiation of each limit and division by r gave the 90% CI for Rdnm. This CI lay completely outside (0.80, 1.25), indicating a disproportionate increase in Cmax."
What limit was he talking about? My sas code is basically identical to detlew's above and there's no apparent "limit" in the output that's similar to what Smith mentioned. I tried also adding
Many thanks.
Man, I should checked here before I started my work. It could save me a lot of time...
Recently I was helping one of my colleagues for dose proportionality study and power model in Smith's article is the preferred method. While I did figured out the "correct" degree of freedom method and reproduce all reported results such as intercept, slope, and 90% CI of those values, ρ1, ρ2, the ratio of dose-normalised geometric mean value Rdnm,..., I could not figure out how Smith obtained the 90% confidence interval for Rdnm (0.477, 0.698).
According to Smith , testing θL < Rdnm < θU to draw conclusion of dose proportionality is equivalent to testing 1 + ln(θL)/ln(r) < β1 < 1 + ln(θH)/ln(r). The latter is what we do and obtaining 90% CI for slope is easy enough and we can judge of dose proportionality based on that. However, it's also interesting to be able to reproduce all Smith's results.
In his article (pp.1282, 2nd paragraph), Smith wrote that "The 90% CI for the difference in log-transformed means was calculated within the MIXED procedure. Exponentiation of each limit and division by r gave the 90% CI for Rdnm. This CI lay completely outside (0.80, 1.25), indicating a disproportionate increase in Cmax."
What limit was he talking about? My sas code is basically identical to detlew's above and there's no apparent "limit" in the output that's similar to what Smith mentioned. I tried also adding
ESTIMATE
or LSMEANS
statement with various codes, couldn't get it at all. Any help? Many thanks.
—
All the best,
Shuanghe
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_dnmShuanghe 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_dnm Shuanghe 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