隨機分配對照臨床試驗（RCT）有三種

Δ: 二組（治療組 vs 對照組）的相差，δ：假設的 Δ 量，H0: 虛無假設，H1: 對立假設。


1. 優越性（試驗組、安慰劑對照組）：H0: Δ ≤ δ, H1: Δ > δ，大部分的 RCT 都是這一類試驗，大部分的 δ 被假設是等於 0。用治療意向法（intention-to-treat，用病人被分配的組別，而非真正接受的治療）分析。


2. 不劣性：H0: Δ ≤ -δ, H1: Δ > -δ, 由於 δ（不劣性臨界值）> 0，需要的樣本數一般比優越性試驗更大，適用於新的方法比較簡單、方便、便宜、低副作用的情形。要特別注意病人的遵從性，而且當用治療意向法及符合方案法（per protocol，用病人真正接受的治療）分析的結論一致時，才是比較可信的。


a. 二組（試驗組、活性對照組）：假設活性對照組的效果勝過安慰劑組（”assay sensitivity”），而且效果跟以前活性對照組 vs 安慰劑組的 RCT 一樣（”constancy assumption”）。


M1: 活性對照的預期效果

M2: 臨床上可接受試驗組 vs 活性對照組最大的差異, M2 < M1


臨界值固定（95%-95%）法：第一個 95% M1 是（至少二個活性對照組 vs 安慰劑組 RCT 的）95% 信賴區間下限或是（只有ㄧ個 RCT 的）99% 信賴區間下限（，第二個 95% 是 δ。


b. 三組（試驗組、活性對照組、安慰劑組）：比較正確，但是比較少用（比較難做、比較貴）。


淺談美國 FDA 不劣性試驗指引最終版之修訂 17

https://www.cde.org.tw/Content/Files/Knowledge/062f6a8c-b52f-412b-a7a2-ad7c1aaaaf51.pdf


淺談不劣性試驗 18

https://www.stroke.org.tw/GoWeb2/include/index.php?Page=5-1&paper02=13142474895bc966317133f


3. 相等性：H0: |Δ| ≥ δ, H1: |Δ| < δ，這種 RCT 的數量最少。


Sample Size Formulas for Different Study Designs

https://riskcalc.org/samplesize/SampleSizeEstimation_Supplement_Chest2020.pdf?ssp=1&setlang=zh-TW&safesearch=moderate


Reporting of Multi-Arm Parallel-Group Randomized Trials-Extension of the CONSORT 2010 Statement 19

https://jamanetwork.com/journals/jama/fullarticle/2731183?ssp=1&setlang=zh-TW&safesearch=moderate


CONSORT 2010 Explanation and Elaboration: updated guidelines for reporting parallel group randomised trials

https://www.bmj.com/content/340/bmj.c869


http://www.tsim.org.tw/journal/jour21-6/04.PDF

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