目標試驗模擬（Target trial emulation）

利用觀察數據來模仿隨機對照試驗(RCT)結果

優點:

1. 成本效益高,因為利用現有數據,無需招募參與者或進行新的試驗。 

2. 可以比傳統 RCT 更快得出結果。

3. 樣本量更大,可提高結果的精確度。

4. 估計的治療效果更具普遍性，因為不像 RCT 一樣具有狹窄的收納/排除條件。

5. 驗證或補充RCT結果,提供進一步的治療有效性證據。

6. 減少：零時（前導時間/不死時間）偏差、錯誤分類偏差、選擇偏差（收納/排除條件）、適應症干擾、干擾因子。

缺點:

1. 對數據和治療效果的強假設可能並不成立。

2. 選擇偏差。  

3. 無法控制干擾變數,導致治療效果估計偏差。

4. 不涉及隨機化,導致治療效果估計偏差。

5. 高度依賴統計模型。

6.假設和方法不完全透明或可重現。 

7. 沒有標準化的模擬方法,不同研究結果難以比較。

8. 監管機構可能不接受模擬結果作為治療有效性的證據。

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