<ARTICLE> 5 <CIK> 0001022079 <NAME> QUEST DIAGNOSTICS INCORPORATED <MULTIPLIER> 1000 <CURRENCY> US <PERIOD-TYPE> 12-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-START> JAN-01-1997 <PERIOD-END> DEC-31-1997 <EXCHANGE-RATE> 1 <CASH> 161,661 <SECURITIES> 0 <RECEIVABLES> 238,269 <ALLOWANCES> 89,870 <INVENTORY> 30,360 <CURRENT-ASSETS> 571,884 <PP&E> 250,223 <DEPRECIATION> 326,195 <TOTAL-ASSETS> 1,400,928 <CURRENT-LIABILITIES> 295,146 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 1,000 <COMMON> 1,198,494 <OTHER-SE> (657,834) <TOTAL-LIABILITY-AND-EQUITY> 1,400,928 <SALES> 1,528,695 <TOTAL-REVENUES> 1,528,695 <CGS> 927,864 <TOTAL-COSTS> 1,429,987 <OTHER-EXPENSES> 4,131 <LOSS-PROVISION> 118,223 <INTEREST-EXPENSE> 40,996 <INCOME-PRETAX> (19,508) <INCOME-TAX> 3,202 <INCOME-CONTINUING> (22,260) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (22,260) <EPS-PRIMARY> (.077) <EPS-DILUTED> (.077)