Table 3. Guidelines for Assessment of Vitamin B12 Levels.

Guideline	Whom to Test?	How Frequently?	Overall Recommendation
BC Guidelines and Protocols Advisory Committee, 2012 (19)	Patients with unexplained neurologic symptoms (paresthesia, numbness, poor motor coordination, memory lapses) Patients with acrocytic anemia or macrocytosis	Not reported	Routine screening for vitamin B12 deficiency is not recommended
Smellie et al, 2005 (20)	Patients with acrocytic anemia Patients with acrocytosis Patients with specific neurocognitive abnormalities	”There is no obvious merit in repeating vitamin B12 measurements unless lack of compliance is suspected or anemia recurs”	Not reported
Andres et al, 2004 (21)	Elderly patients with malnutrition All patients in institutions and psychiatric hospitals All patients with hematologic or neurocognitive manifestations of vitamin B12 deficiency	Not reported	Not reported