<ARTICLE> 5 <CIK> 0001022079 <NAME> Quest Diagnostics Incorporated <MULTIPLIER> 1000 <CURRENCY> US <PERIOD-TYPE> 3-MOS <FISCAL-YEAR-END> Dec-31-1998 <PERIOD-START> Jan-01-1998 <PERIOD-END> Mar-31-1998 <EXCHANGE-RATE> 1.000 <CASH> 172,584 <SECURITIES> 0 <RECEIVABLES> 242,646 <ALLOWANCES> 75,150 <INVENTORY> 29,958 <CURRENT-ASSETS> 581,618 <PP&E> 247,690 <DEPRECIATION> 335,681 <TOTAL-ASSETS> 1,403,578 <CURRENT-LIABILITIES> 299,448 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 1,000 <COMMON> 1,201,834 <OTHER-SE> (651,375) <TOTAL-LIABILITY-AND-EQUITY> 1,403,578 <SALES> 367,875 <TOTAL-REVENUES> 367,875 <CGS> 218,040 <TOTAL-COSTS> 338,486 <OTHER-EXPENSES> 1,225 <LOSS-PROVISION> 23,830 <INTEREST-EXPENSE> 9,114 <INCOME-PRETAX> 13,670 <INCOME-TAX> 7,039 <INCOME-CONTINUING> 6,631 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 6,631 <EPS-PRIMARY> 0.22 <EPS-DILUTED> 0.22