Clinically studied and supported by over 25 peer reviewed, published papers on its safety, efficacy and stability.  The following research is probiotic strain-specific and relates to the patented Bacillus coagulans that is in goodguts Probiotic Tea. 

Bacillus Coagulans As A Probiotic. Food Science & Technology Bulletin: Functional Foods 2010, 7(7): 103-109 D. Keller, S. Farmer, A.L. McCartney, G.Gibson.

This study discusses evidence for Bacillus coagulans effectiveness as a therapeutic probiotic and its heat stability overcoming the limitations of other probiotics.