有沒有用過能量水？

[clement]

有沒有用過能量水？
http://raymondwoo.blogspot.com/2006/07/blog-post_15.html



原來醫學證據有分五級
http://www.cebm.net/levels_of_evidence.asp#levels

[parozov]

:haha: 應該冇人認有用過:haha:
不如問其他地方有没有類似的東西?

[wonggk]

原來醫學證據有分五級
http://www.cebm.net/levels_of_evidence.asp#levels
Actually there are some debates among researchers on whether Randomized Control Trials (RCT's) (Level 1) are truely "better" than cohort studies (lower levels). The issue is internal validity vs. external validity. In a RCT, in order to prove that X-->Y, it is often necessary to prescreen participants so that the control group and the treatment group are very similiar.

The problem is that in doing so, a treatment found to be efficaious may not be effective when made available to the overall population. When the drug is prescribed to the public, patients often have multiple co-morbid conditions not found in the clinical trial subjects, and therefore having adverse effects not detected in a "clean" clinical RCT.

The medical community is now placing more weights on post-market cohort studies in order to address this issue. But this is analog to the class statistics type I vs. type II error. The cleaner the RTC, the more chance that it will have excluded potential interaction effects. :dunno: