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The rule of four: a systematic approach to diagnosis of common pediatric hematologic and oncologic disorders
1Department of Pediatric Hematology/Oncology, St. Joseph Children's Hospital, 3001 W. M. L. King Jr. Blvd, Tampa, FL 33607, USA. hanschris-toph.rossbach@baycare.org
Abstract:
The "Rule of Four" facilitates a rapid and focused approach to the diagnosis of the common hematologic and oncologic disorders encountered in general pediatric practice. This system relies on four recurrent but different clinical entities or laboratory tests relevant to the diagnosis of children with anemia, excessive bleeding or clotting, and common malignancies. For each disorder, there is a discussion of a variety of four lab tests or factors pertinent to a differential diagnosis.
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