ICD-9-CM Volumes 1 & 2 for physicans is used for physician billing.The products from AMA, Ingenix, Contexo Media, PMIC and Unicor provide complete official coding guidelines, summary of medical code changes for the current year, intuitive symbols and color-coded bars highlight all Medicare code edits crucial to correct reimbursement , valid three digit code table, and fourth and fifth digit requirement symbols, clinically oriented diagnosis definitions and illustrations plus age and sex edits