Database	Date of Search	Search terms
CABI database	31 July 2015	TS = (("sickle cell" OR "haemoglobin S disease" OR "haemoglobin S disorder" OR "HbS disease") AND ("folic acid" OR folate OR "vitamin B9" OR "vitamin B‐9" OR metafolin OR levomefolate OR folvite OR folacin OR 5‐methyltetrahydrofolate OR 5‐methylTHF) AND (“randomized controlled trial” OR “controlled clinical trial” OR randomized OR placebo OR “drug therapy” OR randomly OR trial OR groups)) Results: 27