Definitions
Hemoglobin (Hb) <11 g/dL was used to define anemia, according
to WHO criteria.36 Participants were classified as
having ID if their serum ferritin (SF) was <30 ng/mL or
transferrin saturation (TS) was <16% (TS = SI/TIBC
x100).37 IDA was diagnosed if there was compatibility
with either laboratory criteria or therapeutic response to iron therapy.
The diagnosis of β-thal trait was based on Hb A2 level
>3.5%. Infants with Hb F>10% were
investigated for common beta-globin gene deletions to diagnose δβ-thal
traits and hereditary persistence of fetal hemoglobin (HPFH) (Viprakasit
V’s personal communication).38