Study Design
This retrospective study was performed in the most southern part of
Jordan (Aqaba province). Venous blood samples were collected from
different hospitals in Aqaba, with a total number of 281 samples.
Written informed consent was obtained from all participants, and the
data were collected where it related to location, gender, age, and
general health of the participants who were living in Aqaba. Exclusion
criteria included subjects who showed diseases which lead to cobalamin
deficiency such as peptic ulcer, gastrointestinal problem, pregnancy,
diabetes, and individuals under vitamin B12 supplementation.