1. Identifying patient preoperative risk factors and postoperative adverse events in administrative databases;Best;J Am Coll Surg,2002
2. ICD-9-CM Official Guidelines for Coding and Reporting. Coding Clinic for ICD-9-CM 2002;19:21–71
3. ICD-9-CM Coding Handbook, with Answers. 2000 Revised Edition;Brown,2000
4. Coding Clinic for ICD-9-CM 1994;11:7
5. Coding Clinic for ICD-9-CM 1984;1:12