1 Exhibit 23.03 Consent of Ernst & Young LLP Independent Auditors We consent to the incorporation by reference in the Registration Statements (Nos. 33-91026, 333-03603, 333-16553, 333-40493, 333-60797, 333-19009, 333-28919, 333-38181, 333-40497, 333-48403, 333-65743 and 333-75183) of Quintiles Transnational Corp. of our report dated January 29, 1999, with respect to the financial statements of ENVOY Corporation included in this Current Report on Form 8-K to be filed with the Securities and Exchange Commission on or about July 15, 1999. /s/ Ernst & Young LLP Nashville, Tennessee July 15, 1999