標靶治療能選擇性地攻擊或抑制癌細胞中重要的分子或訊號傳遞路徑，因而能在不影響正常細胞下達成治療的目標。此一嶄新的治療策略，已成功地運用於多項癌症的治療，但相關研究發現此種治療方式常只針對特定子群體的病患有顯著療效，於是標靶藥物在進行臨床試驗中，子群分析(subgroup analysis)是很重要的課題。為了降低進入子群分析門檻，Alosh和Huque(2009)提出靈活策略檢定(flexible strategy testing)，此方法引進新的參數，在確保總誤差率(familywise Type I error rate)受控下，有效提升子群檢定力，而此方法留下了一個開放問題，在給定目標對立假設(target alternative)下，是否存在最佳參數設定。本論文首先探討在靈活策略檢定下，參數對母群檢定力及子群檢定力之影響，從而確認在樣本數固定下，欲提升子群檢定力，必使得母群檢定力下降，故以損不及益的概念為出發點，即在子群檢定力的增加不低於母群檢定力的減少設限下，擬定兩種準則：(一)子群檢定力最大化；及(二)總檢定力最大化, 並給出此二準則下的若干結果。

Targeted therapy can more precisely identify and attack cancer cells or inhibit important molecular signaling pathway, usually while doing little damage to normal cells and achieving treatment goals. This new treatment regimen has been successfully applied to a number of cancers. However, some studies indicate that targeted therapy has a significant effect only for special groups of patients. It carries out that not only the efficacy of overall population but also that of subgroup analysis is an important issue in targeted therapy clinical trials. In order to reduce the threshold to enter the subgroup analysis, Alosh and Huque (2009) proposed a flexible strategy for testing subgroups and overall population. This strategy introduces new parameters to improve the power of subgroup test effectively while the familywise Type I error rate is controlled. It brings out an open question that whether there exist any optimal parameter settings for a given alternative hypothesis. In this thesis, first, we will discuss the influence of power of overall population test and subgroup test in flexible strategy testing. Second, we develop two criteria in the concept of loss less than obtainment (means the increases of power of subgroup test is less than the decreases of power of overall population test) as a starting point: (1) the maximization of power for subgroup test, and (2) the maximization of power for overall population test and subgroup test. Finally, we provide some results for two criteria.

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萬久珮(2009)，胃癌之分子標靶治療–著重於上皮生長因子接受器抗體(Cetuximab) 併用化學治療,及其相關藥物基因體學之研究，台灣大學微生物學研究所碩士論文。