Randomized Controlled Trial
Effect of a Psidii guajavae folium extract in the treatment of primary dysmenorrhea: a randomized clinical trial.
J Ethnopharmacol. 2007 Mar 21; 110 (2): 305-10.
Randomized Controlled Trial
Effect of pine bark extract (Pycnogenol) on symptoms of knee osteoarthritis.
Phytother Res. 2008 Aug 1; 22 (8): 1087-92.