Risk Factors and Frequency of Vitamin B12 Deficiency among Patients Visiting Primary Care Clinics in Karachi, Pakistan. J. Bahria Univ. Med. Dent. Coll. [Internet]. 2025 Oct. 24 [cited 2026 May 9];15(04):318-25. Available from: https://jbumdc.bahria.edu.pk/index.php/jbumdc/article/view/273