1 EXHIBIT 21 SUBSIDIARIES OF REGISTRANT SUBSIDIARY STATE OF INCORPORATION - ---------- ---------------------- Health Data Sciences Corporation Delaware Impact Innovations Government Group, Inc. Maryland Impact Innovations Group, Inc. Delaware Impact Innovations Holdings, Inc. Delaware Medaphis ER Physician Services, Inc. Georgia Medaphis Physician Services Corporation (1) Georgia Per-Se Technologies, Inc. California Per-Se Transaction Services, Inc. (2) Indiana - --------- (1) Medaphis Physician Services Corporation also does business as: a. Anescor (used in Los Angeles and Orange, CA, offices) b. Billing and Professional Services (used in Tucker, GA, office) c. Medical Management (used in Montgomery, AL, office) d. Medical Management of New England e. Medical Management Sciences f. Medical Office Consultants (used in Los Angeles, CA, office) (2) Per-Se Transaction Services, Inc., also does business as: a. Computers Diversified (used in Southfield, MI, office) b. Nationwide Collection (used in Southfield, MI. office) c. The Halley Exchange (used in Bartlett, IL, office)