Database/ Resource	Strategy
PubMed (1946 onwards)	(beta thalassemia OR beta thalassaemia) AND (hydroxyurea OR hydroxycarbamide OR hydrea OR droxia OR mylocel OR oncocarbide)
ClinicalTrials.gov	thalassaemia AND (hydroxyurea OR hydroxycarbamide)
WHO ICTRP	[Advanced search option] CONDITION: Thalassaemia OR thalassemia AND INTERVENTION: hydroxyurea OR hydroxycarbamide OR hydrea OR droxia OR mylocel OR oncocarbide RECRUITMENT STAUS: All
Greylit.org	SEARCH 1: hydrox SEARCH 2: droxia SEARCH 3: hydrea SEARCH 4: mylocel SEARCH 5: oncocarbide