Khalighi Sikaroudi, M. et al. 2020. Effects of vitamin D3 supplementation on clinical symptoms, quality of life, serum serotonin (5-hydroxytryptamine), 5-hydroxy-indole acetic acid, and ratio of 5-HIAA/5-HT in patients with diarrhea-predominant irritable bowel syndrome: A randomized clinical trial. EXCLI Journal. 19, (May 2020), 652–667. DOI:https://doi.org/10.17179/excli2020-2247.