The Power of Observation

作者：Clark David A^*

来源：American Journal of Reproductive Immunology, 2011, 66(2): 71-75.

DOI：10.1111/j.1600-0897.2010.00963.x

• Controlled trials
• evidence-based medicine
• IVIG
• recurrent spontaneous abortion

Problem
In the golden age of evidence-based medicine, how should one view the cohort-controlled study of IVIG + anti-TNF-alpha (Humira) in recurrent in vitro fertilization (IVF) failure patients with an elevated Th1/Th2 cytokine production ratio.
Method
Critical analysis of the nature of evidence for causation.
Results
A better delivery rate and a live birth rate per embryo approaching the estimated maximum possible in patients whose elevated Th1/Th2 ratio corrected to normal compared to those with an incomplete correction is a strong argument for causation. A maximal improvement when treatment was given 61-120 days before embryo transfer suggests a possible mechanism via improving the physiology during follicle development.
Conclusion
Independent replication to verify results would augment power.

• 出版日期2011-8