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NightlordTW
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Add calculations
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---
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title: "Bioequivalence Tests for Parallel Trial Designs: 3 Arms, 2 Endpoints"
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title: "Bioequivalence Tests for Parallel Trial Designs: 2 Arms, 3 Endpoints"
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author: "Thomas Debray"
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date: "`r format(Sys.time(), '%B %d, %Y')`"
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output:
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fig_width: 9
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fig_height: 6
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vignette: >
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%\VignetteIndexEntry{Bioequivalence Tests for Parallel Trial Designs: 3 Arms, 2 Endpoints}
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%\VignetteIndexEntry{Bioequivalence Tests for Parallel Trial Designs: 2 Arms, 3 Endpoints}
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%\VignetteEngine{knitr::rmarkdown}
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%\VignetteEncoding{UTF-8}
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bibliography: 'references.bib'
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"EU-INF" = c("39,360 $\\pm$ 12,332", "37,022 $\\pm$ 9398", "126.2 $\\pm$ 17.9"))
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kableExtra::kable_styling(kableExtra::kable(data,
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col.names = c("PK measure", "SB2", "EU-INF"),
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col.names = c("PK measure", "SB2", "Remicade (EU)"),
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caption = "Primary PK measures between test and reference product. Data represent arithmetic mean +- standard deviation."),
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bootstrap_options = "striped")
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```
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# Methodology and Assumptions
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The bioequivalence analysis focuses on two key pharmacokinetic endpoints:
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$$H_1: E_L<\mu_{T}^{(j)}-\mu_{R}^{(j)} < E_U \quad\text{for all}\;j$$
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The null hypothesis $H_0$ is rejected if and only if all of the null hypotheses associated with each of the $K$ primary endpoints are rejected at a significance level of $\alpha$.
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## Decision Rule
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The null hypothesis ($H_0$) is rejected if, and only if, all null hypotheses associated with the $K$ primary endpoints are rejected at a significance level of $\alpha$. This ensures that equivalence is established across all endpoints simultaneously.
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## Statistical Considerations
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* **Type I Error Control**: Since rejection of $H_0$ requires all individual null hypotheses to be rejected, there is no need for multiplicity adjustments. The Type I error rate is controlled by the design.
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* **Impact on Power**: Requiring equivalence across multiple endpoints decreases the overall power of the test. The Type II error increases as the number of primary endpoints ($K$) grows, which can make equivalence testing more challenging [@mielke_sample_2018].
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## Independent Testing of Pharmacokinetic (PK) Measures
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If each pharmacokinetic (PK) measure is tested independently, the following sample sizes would be required for each endpoint to achieve a 5\% significance level:
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```{r}
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# Sample size calculation for AUCinf
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(sim_AUCinf <- sampleSize(
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power = 0.9, # Target power
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alpha = 0.05, # Significance level
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arm_names = c("SB2", "EU_Remicade"), # Names of trial arms
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list_comparator = list("EMA" = c("SB2", "EU_Remicade")), # Comparator configuration
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mu_list = list("SB2" = 38703, "EU_Remicade" = 39360), # Mean values
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sigma_list = list("SB2" = 11114, "EU_Remicade" = 12332), # Standard deviation values
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list_lequi.tol = list("EMA" = 0.8), # Lower equivalence margin
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list_uequi.tol = list("EMA" = 1 / 0.8), # Upper equivalence margin
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ncores = 1, # Number of computation cores
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nsim = 1000 # Number of stochastic simulations
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))
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```
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If we were to test each PK measure independently, we would find a total sample size of $N=$ `r sim_AUCinf$sim_AUCinf$response$n_total` for AUCinf, $N=56$ for AUClast, and $N=20$ for Cmax. This means that we would have to enroll `r sim_AUCinf$sim_AUCinf$response$n_total` + $56+20 = 152$ patients in order to reject $H_0$ at a significance level of 5\%.
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# References

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