隨機分配的方法

分配隱藏（allocation concealment）：病人被分配前沒有人能預測分配結果、分配法則。例如：隨機分配的結果用不透明的信封當眾打開。


簡單隨機分配：用亂數表或抽籤（丟銅板正面 A 組、反面 B 組，丟骰子 1-3 A 組、4-6 B 組）決定分組，有可能二組的人數不平均。


Restricted randomization: 

區塊隨機分配（permuted block）：先把病人分區（區塊的大小是組數的倍數）。例如：100 個人，每ㄧ區 6 個人，每一區再隨機排列（permuted）分配成 A、B 組，如此能保證二組的人數幾乎是平衡的。

https://www.sealedenvelope.com/simple-randomiser/v1/lists


決定區塊大小的方法：

https://www.sealedenvelope.com/randomisation/simulation/


Randomistation in Clinical Trials 12

https://www.researchgate.net/publication/11038235_Randomistation_in_Clinical_Trials


https://www.sealedenvelope.com/help/redpill/latest/block/


https://www.statisticshowto.com/permuted-block-randomization/


分層隨機分配：把病人依據會影響結局的因子分層（例如：性別、年齡、疾病等），每一層再區塊（排列）隨機分配成 A、B 組。壞處是必須先收納所有的受試者才能分層，因此這樣的做法很少見。


A roadmap to using randomization in clinical trials 21

https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/s12874-021-01303-z

big stick design bsd(3)


https://cran.r-project.org/web/packages/randomizeR/index.html


Importance of Block Randomization When Designing Proteomics Experiments 20

https://pubs.acs.org/doi/10.1021/acs.jproteome.0c00536


An overview of randomization techniques: An unbiased assessment of outcome in clinical research 11

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3136079/

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