A topic in Clinical Evidence summarizes the results of one RCT (n=246) that compared selenium sulphide shampoo, ketokonazole 2% shampoo and placebo. There was a significantly greater reduction in mean adherent dandruff scores (percentage reduction 66.7% with selenium, 44.5% with placebo). Significantly more people responded (global improvement): AR for responding 54.7% with selenium, 28.6% with placebo, p=0.004).
Comment: The quality of evidence is downgraded by sparse data.