<qa>  What is the primary and secondary diagnosis related to Venous Thromboembolism?The design of our study is retrospective in nature. We are interested primarily in the use of LMWH in patients admitted to the general medicine services between January 1, 1997 and February 1, 2001 with a primary and secondary diagnosis related to Venous Thromboembolism, including specific ICD-9 codes. 