(A) Samples were sent to the central reference laboratory at NIBD where the tests were repeated to establish reliability. (B) The following tertiary health care centers (from left to right) are shown: Hayatabad Medical Complex (HMCP); Lady Reading Hospital (LRHP); Khyber Pakhtunkhwa (KP); Fatimid Foundation Karachi (FFK); National Institute of Blood Diseases (NIBD); Chughtai’s Laboratory (CL); Children’s Hospital Lahore (CHL); and Pakistan Atomic Energy Commission (PAEC). For each tertiary health care center, “N” indicates the number of patients with ARBDs and the number in parentheses indicates the total number of patients initially recruited from each center. Prothrombin time (PT), activated partial thromboplastin time (APTT), bleeding time, and fibrinogen levels were measured. Patients with isolated prolonged APTT were tested for factor VIII (FVIII) and FIX using factor assays This was followed by FXI:C-level assessment for patients with normal FVIII and FIX levels. Samples were reanalyzed except platelet aggregation studies. All rare clotting factor defects such as FII, VII, X, XI , and XIII were tested in a reference laboratory (NIBD) because of the unavailability of testing facilities. Platelet aggregation studies were repeated in PAEC, CL, CHL, and NIBD. Patients with low FVIII levels were screened for VWD. Patients with simultaneous prolongation of PT and APTT were tested for FII, FV, and FX. Peripheral blood film examination and platelet aggregation studies were performed to assess platelet disorders. Urea clot solubility testing was performed to detect FXIII levels if platelet function tests were normal. Sanger sequencing was performed for genetic analysis of patient samples. Descriptive analysis was performed using SPSS version 16 software.