This Fourth Edition continues the BRS tradition of an outline format with content review followed by USMLE-style questions at the end of each chapter. Each chapter also features a high-yield section on clinical correlations. The book is concise and well illustrated, with line drawings and electron micrographs. A USMLE format comprehensive examination, which contains 500 questions, is at the end of the book. This edition includes a CD-ROM with all of the text questions plus more, and an additional 100 color images to accompany these questions, also representative of the USMLE style.