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RCTs can be expensive; for a mean cost of US$12 million per RCT.  Nevertheless, the return on investment of RCTs may be high, in that the same study projected that the 28 RCTs produced a "net benefit to society at 10-years" of 46 times the cost of the trials program, based on evaluating a quality-adjusted life year as equal to the prevailing mean per capita gross domestic product.

RCTs can be expensive; for a mean cost of US$12 million per RCT.  Nevertheless, the return on investment of RCTs may be high, in that the same study projected that the 28 RCTs produced a "net benefit to society at 10-years" of 46 times the cost of the trials program, based on evaluating a quality-adjusted life year as equal to the prevailing mean per capita gross domestic product.

随机对照试验可能很昂贵，每次随机对照试验的平均成本为1200万美元。然而，rct 的投资回报率可能很高，因为同一项研究预测，28个 rct 产生的“10年社会净效益”是试验项目成本的46倍，其基础是评估一个质量调整寿命年等于当前人均国内生产总值的平均值。

随机对照试验可能很昂贵，每次随机对照试验的平均成本为1200万美元。然而，随机对照试验的投资回报率可能很高，因为同一项研究预测，28个 随机对照试验 产生的“10年社会净效益”是试验项目成本的46倍，其基础是评估一个质量调整寿命年等于当前人均国内生产总值的平均值。

{{Main|Sample size determination}}

{{Main|Sample size determination}}