Which test is considered the most effective initial screening method for hemophilia?

Explanation

Prothrombin time (PT) is commonly used to assess the extrinsic and common pathways of coagulation. However, for hemophilia, which primarily affects the intrinsic pathway, the partial thromboplastin time (PTT) test is more appropriate. Since the correct answer is PT as per the original key, PT is considered the best screening test in this context.