"Conclusive findings" refers to results or information that are final and decisive, leaving no doubts or uncertainty about a particular matter or the outcome of a study or investigation. Full definition
The most conclusive finding of the research is that students from lower socioeconomic levels can benefit from a year - round calendar — if the school intentionally plans to include extra learning opportunities during the breaks. (ascd.org)
One of the most conclusive findings in education research is that teachers matter. (educationnext.org)
@Scott: I find gravity fascinating as we can experience it, test it, and make those predictions and arrive at conclusive findings, but yet it still remains a phenomenon as we can not build anything to replicate it. (religion.blogs.cnn.com)