An example of how hard it is to get statistically significant findings in research.

An unsure scientist.

In this research paper they wanted to see if doing an endometrial scratch (using a small tube used to biopsy the lining of the uterus) before an embryo transfer would increase live birth compared to not doing the procedure in patients with a good prognosis. The research was just published this year in the Journal of Reproductive Medicine. The trial registration date was in 2017. They found the live birth rate in the scratch group to be 64% compared to 57% in the control group. However the findings were not significant because they had 593 participants by the end of the trial and they need 792 to make the findings statistically significant. So they worked for over 10 years (if you count the work done before the official trial registration) with 1 group 7 % higher and yet the final conclusion is no statistically significant difference was found due to too small a sample size. All that time, effort and money and it’s still , we don’t really know any more about the question. A window into the often frustrating world of being a researcher!
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