EJIFCCReassessing Vitamin D Deficiency: Data Driven Indirect Reference Intervals for 25-Hydroxyvitamin D in Pakistan via refineR AlgorithmBy Sibtain Ahmed, Amal Mahmood, Ashish Agravatt, Imran Siddiqui, Aysha Habib KhanStudy in peopleBiomarkersPaperThe paperSibtain Ahmed, Amal Mahmood, Ashish Agravatt, Imran Siddiqui, Aysha Habib KhanAga Khan UniversityEJIFCC, 31 Aug 2026PubMed 42730068