The phlebotomist attempted to collect a prothrombin (PT) specimen from a patient. The tube filled part of the way and then stopped. The phlebotomist withdrew the tube, restuck the patient, and finished filling the light blue tube. Sometime later the phlebotomist is asked to recollect the specimen. Why would the speciment need to be recollected? What should the phlebotomist have tried before withdrawing the needle the first time?

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