Exhibit 99.1

QUEST DIAGNOSTICS REPORTS STRONG FINANCIAL RESULTS
IN FOURTH QUARTER AND FULL YEAR 2004

-- Earnings per Share Expected to Grow 14-16% in 2005 --

TETERBORO, N.J., JANUARY 27, 2005--Quest Diagnostics Incorporated (NYSE: DGX),
the nation's leading provider of diagnostic testing, information and services,
announced that for the fourth quarter ended December 31, 2004, net income
increased to $126 million, compared to $108 million in 2003. Earnings per
diluted share increased 21% to $1.23, before a required change in accounting for
the company's contingent convertible debentures. After the change in accounting,
reported earnings per diluted share were $1.20.

Fourth quarter revenues grew 6.6% over the prior year to $1.3 billion. Clinical
testing volume, measured by the number of requisitions, increased 4.1%, and
revenue per requisition increased 1.9%. The remainder of the revenue growth was
contributed by the company's non-clinical testing businesses.

For the fourth quarter, operating income was $221 million, or 17.2% of revenues,
compared to $197 million, or 16.4% of revenues, in 2003. Bad debt expense
improved to 4.2% of revenues, from 4.7% a year ago. Days sales outstanding
improved to 47 days compared to 48 days a year ago. Cash from operations was
$264 million. During the quarter the company repurchased 3.8 million common
shares for $353 million, including $254 million from GlaxoSmithKline. Capital
expenditures were $42 million.

"Our strong financial performance reflects the benefits of ongoing efforts to
accelerate organic growth," said Surya N. Mohapatra, Ph.D., Chairman and Chief
Executive Officer. "We continue to generate substantial cash flow, which we are
investing to further differentiate our services to physicians and patients, and
return value to shareholders. We expect 2005 to be another solid year, with
earnings per share increasing 14% to 16%."

For the full year 2004, net income increased to $507 million, and earnings per
diluted share increased 18% to $4.87, excluding previously disclosed second
quarter charges and before the change in accounting for the company's contingent
convertible debentures. Diluted earnings per share were $4.77, excluding the
second quarter charges and after the change in accounting. Reported net income
was $499 million, or $4.69 per diluted share, including the second quarter
charges and after the change in accounting.

Revenues for the full year increased 8.2% to $5.1 billion. Unilab, acquired
February 28, 2003, accounted for approximately 1.5% of the growth. Operating
income, excluding the second quarter charge related to the CEO succession
process, was $902 million, or 17.6% of revenues, compared to $796 million, or
16.8% of revenues in 2003. Including the second quarter charge, operating income
was $891 million, or 17.4% of revenues. Cash from operations totaled $799
million, compared to $663 million in 2003. During 2004 the company repurchased
8.3 million common shares for $735 million and made capital expenditures of $176
million.

Outlook for 2005

For the full year 2005, revenues are expected to grow between 5% and 6%.
Operating income is expected to be between 18% and 19% of revenues; cash from
operations is expected to approach $800 million; and capital expenditures are
expected to be between $210 million and $230 million. The company expects full
year earnings per diluted share of between $5.45 and $5.55, an increase of 14%
to 16% compared to 2004 diluted earnings per share of $4.77 before special
charges. Estimates for 2005 earnings per diluted share, operating income and
cash from operations are before the impact of the accounting change for
equity-based compensation, effective July, 2005.

Quest Diagnostics will hold its fourth quarter conference call on January 27 at
8:30 A.M. Eastern Time. To hear a simulcast of the call over the Internet or a
replay, registered analysts may access StreetEvents at: www.streetevents.com,
and all others may access the Quest Diagnostics website at:
www.questdiagnostics.com. In addition, a replay of the call will be available
from 10:30 A.M. on January 27 through 11 P.M. on February 25 to investors in the
U.S. by dialing 866-481-6893. Investors outside the U.S. may dial 203-369-1512.
No password is required for either number.

Quest Diagnostics Incorporated is the nation's leading provider of diagnostic
testing, information and services, providing insights that enable healthcare
professionals to make decisions that improve health. The company offers the
broadest access to diagnostic testing services through its national network of
laboratories and patient service centers, and provides interpretive consultation
through its extensive medical and scientific staff. Quest Diagnostics is the
leading provider of esoteric testing, including gene-based medical testing, and
provides advanced information technology solutions to improve patient care.
Additional company information is available at: www.questdiagnostics.com.

The statements in this press release which are not historical facts or
information may be forward-looking statements. These forward-looking statements
involve risks and uncertainties that could cause actual results and outcomes to
be materially different. Certain of these risks and uncertainties may include,
but are not limited to, competitive environment, changes in government
regulations, changing relationships with customers, payers, suppliers and
strategic partners and other factors described in the Quest Diagnostics
Incorporated 2003 Form 10-K and subsequent filings.

- Table follows -

Quest Diagnostics Incorporated and Subsidiaries

Consolidated Statements of Operations
For the Three and Twelve Months Ended December 31, 2004 and 2003
(in millions, except per share and percentage data)

Three Months Ended Twelve Months Ended
December 31, December 31,
------------------ --------------------

2004 2003 2004 2003
-------- -------- -------- --------

Net revenues.............................................. $ 1,283.3 $ 1,204.0 $ 5,126.6 $ 4,737.9

Operating costs and expenses:
Cost of services.......................................... 757.4 706.2 2,990.7 2,768.6
Selling, general and administrative....................... 304.6 298.0 1,227.8 1,165.7
Amortization of intangible assets ........................ 0.9 2.1 6.7 8.2
Other operating (income) expense, net .................... (0.2) 0.7 10.2 (1.0)
--------- --------- --------- ---------
Total operating costs and expenses...................... 1,062.7 1,007.0 4,235.4 3,941.5
--------- --------- --------- ---------

Operating income ......................................... 220.6 197.0 891.2 796.4

Other income (expense):
Interest expense, net..................................... (13.3) (14.5) (57.9) (59.7)
Minority share of income.................................. (5.0) (4.8) (19.4) (17.6)
Equity earnings in unconsolidated joint ventures.......... 5.5 4.4 21.0 17.4
Other income, net......................................... 0.2 0.8 0.2 1.3
--------- ------- --------- ---------
Total non-operating expenses, net....................... (12.6) (14.1) (56.1) (58.6)
--------- ------- --------- ---------

Income before taxes ...................................... 208.0 182.9 835.1 737.8
Income tax expense........................................ 81.9 74.6 335.9 301.1
--------- ------- --------- ---------
Net income................................................ $ 126.1 $ 108.3 $ 499.2 $ 436.7
========= ======= ========= =========

Net income before special charges......................... $ 126.1 $ 108.3 $ 507.1 $ 436.7

- ------------------------------------------------------------------------------------------------------------

Basic earnings per common share:
Net income................................................ $ 1.26 $ 1.04 $ 4.90 $ 4.22

Net income before special charges......................... $ 1.26 $ 1.04 $ 4.98 $ 4.22

Weighted average common shares outstanding - basic........ 100.4 103.8 102.0 103.4

- ------------------------------------------------------------------------------------------------------------

Diluted earnings per common share:
Net income................................................ $ 1.20 $ 1.00 $ 4.69 $ 4.04

Net income before special charges......................... $ 1.20 $ 1.00 $ 4.77 $ 4.04

Weighted average common shares outstanding - diluted...... 105.3 109.2 107.1 108.8

- ------------------------------------------------------------------------------------------------------------

Operating income before special charge as a
percentage of net revenues........................... 17.2% 16.4% 17.6% 16.8%

- ------------------------------------------------------------------------------------------------------------

Quest Diagnostics Incorporated and Subsidiaries

Consolidated Balance Sheets
December 31, 2004 and 2003
(in millions, except per share data)

December 31, December 31,
2004 2003
------------ -----------

Assets
Current assets:
Cash and cash equivalents .................................... $ 73.3 $ 155.0
Accounts receivable, net ..................................... 649.3 609.2
Inventories .................................................. 75.3 72.5
Deferred income taxes ........................................ 83.0 109.0
Prepaid expenses and other current assets .................... 50.2 50.1
-------- --------
Total current assets ...................................... 931.1 995.8
Property, plant and equipment, net ........................... 619.5 607.3
Goodwill, net ................................................ 2,506.9 2,518.9
Intangible assets, net ....................................... 11.5 17.0
Deferred income taxes ........................................ 29.4 49.6
Other assets ................................................. 105.4 112.8
-------- --------
Total assets ................................................. $4,203.8 $4,301.4
======== ========

Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable and accrued expenses ........................ $ 669.0 $ 649.9
Short-term borrowings and current portion of
long-term debt ............................................ 374.8 73.9
-------- --------
Total current liabilities ................................. 1,043.8 723.8
Long-term debt ............................................... 724.0 1,028.7
Other liabilities ............................................ 147.3 154.2
Stockholders' equity:
Common stock, par value $0.01 per share; 300 shares
authorized; 106.8 shares issued at both
December 31, 2004 and 2003 ................................ 1.1 1.1
Additional paid-in capital ................................... 2,195.3 2,267.0
Retained earnings ............................................ 818.7 380.5
Unearned compensation ........................................ - (2.3)
Accumulated other comprehensive income ....................... 3.9 5.9
Treasury stock, at cost; 8.7 and 4.0 shares at
December 31, 2004 and 2003, respectively .................. (730.3) (257.5)
-------- --------
Total stockholders' equity ................................ 2,288.7 2,394.7
-------- --------
Total liabilities and stockholders' equity ................... $4,203.8 $4,301.4
======== ========

Quest Diagnostics Incorporated and Subsidiaries

Consolidated Statements of Cash Flows
For the Twelve Months Ended December 31, 2004 and 2003
(in millions)

Twelve Months Ended
December 31,
------------------
2004 2003
------- --------

Cash flows from operating activities:
Net income ............................................... $ 499.2 $ 436.7
Adjustments to reconcile net income to net cash
provided by operating activities:
Depreciation and amortization ............................ 168.7 153.9
Provision for doubtful accounts .......................... 226.3 228.2
Deferred income tax provision ............................ 52.5 33.9
Minority share of income ................................. 19.4 17.6
Stock compensation expense ............................... 1.4 5.3
Tax benefits associated with stock-based compensation
plans ................................................. 71.3 30.5
Other, net ............................................... 4.7 (1.6)
Changes in operating assets and liabilities:
Accounts receivable ................................... (266.4) (254.9)
Accounts payable and accrued expenses ................. 22.3 (6.8)
Integration, settlement and other special charges ..... (18.3) (18.9)
Income taxes payable .................................. 1.1 26.5
Other assets and liabilities, net ..................... 16.5 12.4
------- -------
Net cash provided by operating activities ................ 798.7 662.8
------- -------

Cash flows from investing activities:
Business acquisitions, net of cash acquired .............. - (237.6)
Capital expenditures ..................................... (176.1) (174.6)
Proceeds from disposition of assets ...................... 7.6 9.0
Increase in investments and other assets ................. (5.2) (13.8)
------- -------
Net cash used in investing activities .................... (173.7) (417.0)
------- -------

Cash flows from financing activities:
Proceeds from borrowings ................................. 304.9 450.0
Repayments of debt ....................................... (306.0) (391.7)
Purchases of treasury stock .............................. (734.5) (257.5)
Exercise of stock options ................................ 109.1 29.9
Dividends paid ........................................... (61.4) -
Distributions to minority partners ....................... (16.7) (14.3)
Financing costs paid ..................................... (2.1) (4.2)
Other .................................................... - 0.2
------- -------
Net cash used in financing activities .................... (706.7) (187.6)
------- -------

Net change in cash and cash equivalents .................. (81.7) 58.2
Cash and cash equivalents, beginning of period ........... 155.0 96.8
------- -------
Cash and cash equivalents, end of period ................. $ 73.3 $ 155.0
======= =======

Cash paid during the period for:
Interest ................................................. $ 51.8 $ 59.4
Income taxes ............................................. $ 209.2 $ 212.0

Notes to Financial Tables

1) Basic earnings per common share is calculated by dividing net income by the
weighted average common shares outstanding. Due to a required change in
accounting effective December 31, 2004, the Company included the dilutive
effect of its contingent convertible debentures in its dilutive earnings
per common share calculations using the if-converted method, regardless of
whether or not the holders of these securities were permitted to exercise
their conversion rights, and retroactively restated previously reported
diluted earnings per common share. References to the diluted weighted
average common shares outstanding, including diluted earnings per common
share calculations and related disclosures, have been restated to give
effect to the required change in accounting for all periods presented.

The computation of basic and diluted earnings per common share (using the
if-converted method) is as follows:

Three Months Ended Twelve Months Ended
December 31, December 31,
------------------------ -----------------------
2004 2003 2004 2003
--------- -------- -------- --------
(in millions, except per share data)

Net income available to common stockholders -
basic (A)......................................... $126.1 $108.3 $499.2 $436.7
Add: Interest expense associated with
contingent convertible debentures, net of
related tax effects............................... 0.8 0.8 3.3 3.3
------ ------ ------ -------
Income available to common stockholders -
diluted .......................................... $126.9 $109.1 $502.5 $440.0
====== ====== ====== =======

----------------------------------------------------------------------------------------------------------

Weighted average common shares outstanding -
basic, as reported ............................... 100.4 103.8 102.0 103.4

Dilutive effect of stock options and restricted
common shares granted under the Company's
Employee Equity Participation Program ............ 2.0 2.5 2.2 2.5
------ ------ ------ -------
Weighted average common shares outstanding -
diluted (before the required change in
accounting for the Company's contingent
convertible debentures) (B)....................... 102.4 106.3 104.2 105.9
Dilutive effect of the contingent convertible
debentures........................................ 2.9 2.9 2.9 2.9
------ ------ ------ -------
Weighted average common shares outstanding -
diluted, as reported ............................. 105.3 109.2 107.1 108.8
====== ====== ====== =======

----------------------------------------------------------------------------------------------------------

Basic earnings per common share, as reported......... $1.26 $1.04 $4.90 $4.22

Diluted earnings per common share, as reported....... $1.20 $1.00 $4.69 $4.04

Diluted earnings per common share, before the
required change in accounting for the
Company's contingent convertible debentures* ..... $1.23 $1.02 $4.79 $4.12

* Calculated by dividing income available to common stockholders - basic
(A) by the weighted average common shares outstanding - diluted (before
the required change in accounting for the Company's contingent
convertible debentures) (B)

----------------------------------------------------------------------------------------------------------

2) The following table presents net income and basic and diluted earnings per
common share, had the Company elected to recognize compensation cost based
on the fair value at the grant dates for stock option awards and discounts
granted for stock purchases under the Company's Employee Stock Purchase
Plan, consistent with the method prescribed by Statement of Financial
Accounting Standards No. 123, "Accounting for Stock-Based Compensation", as
amended by Statement of Financial Accounting Standards No. 148, "Accounting
for Stock-Based Compensation Transition and Disclosure an amendment of FASB
Statement No. 123":

Net income
Net income, as reported.............................. $126.1 $108.3 $499.2 $436.7
Add: Stock-based compensation under APB 25.......... 0.2 1.2 1.4 5.3
Deduct: Total stock-based compensation expense
determined under fair value method for all
awards, net of related tax effects................ (11.6) (12.3) (45.1) (52.3)
------ ------ ------ ------
Pro forma net income................................. $114.7 $ 97.2 $455.5 $389.7
====== ====== ====== ======

Earnings per common share
Basic - as reported.................................. $ 1.26 $ 1.04 $ 4.90 $ 4.22
------ ------ ------ ------
Basic - pro forma.................................... $ 1.14 $ 0.94 $ 4.47 $ 3.77
------ ------ ------ ------

Diluted - as reported................................ $ 1.20 $ 1.00 $ 4.69 $ 4.04
------ ------ ------ ------
Diluted - pro forma.................................. $ 1.09 $ 0.90 $ 4.27 $ 3.65
------ ------ ------ ------

The fair value of each option grant was estimated on the date of grant
using the Black-Scholes option-pricing model with the following weighted
average assumptions:

Three Months Ended Twelve Months Ended
December 31, December 31,
------------------------ -----------------------
2004 2003 2004 2003
--------- -------- -------- --------

Dividend yield........................... 0.6% 0.4% 0.7% 0.0%
Risk-free interest rate.................. 3.5% 3.2% 3.1% 2.8%
Expected volatility...................... 46.0% 47.9% 47.2% 48.1%
Expected holding period, in years........ 5 5 5 5

3) Other operating (income) expense, net represents miscellaneous income and
expense items related to operating activities including gains and losses
associated with the disposal of operating assets. For the twelve months
ended December 31, 2004, other operating expense, net includes a $10.3
million second quarter charge associated with the acceleration of certain
pension obligations in connection with the CEO succession process.

4) Interest expense, net for the twelve months ended December 31, 2004,
includes a $2.9 million charge representing the write-off of deferred
financing costs associated with the second quarter 2004 refinancing of the
Company's bank debt and credit facility.

5) In 2003, the Board of Directors authorized a share repurchase program,
which permitted the Company to purchase up to $600 million of its common
stock. In July 2004, the Board of Directors authorized the Company to
purchase up to an additional $300 million of its common stock. Under a
separate authorization from the Board of Directors, in December 2004 the
Company repurchased 2.7 million shares of its common stock for
approximately $254 million from GlaxoSmithKline plc. For the three months
ended December 31, 2004, the Company repurchased approximately 3.8 million
shares of its common stock at an average price of $93.47 per share for $353
million. For the twelve months ended December 31, 2004, the Company
repurchased approximately 8.3 million shares of its common stock at an
average price of $88.21 per share for $735 million. Since the inception of
the share repurchase program, the Company has repurchased approximately
12.3 million shares of its common stock at an average price of $80.54 for
$992 million. For the three and twelve months ended December 31, 2004, the
Company has reissued approximately 0.9 million shares and 3.6 million
shares, respectively, primarily in connection with employee benefit plans.
At December 31, 2004, $162 million of the share repurchase authorizations
remained available. In January 2005, the Board of Directors expanded the
share repurchase authorization by an additional $350 million, bringing the
total amount authorized and available for repurchases to $512 million.

6) Free cash flow represents net cash provided by operating activities less
capital expenditures. Free cash flow is presented because management
believes it is a useful adjunct to cash flow from operating activities and
other measurements under accounting principles generally accepted in the
United States since it is a meaningful measure of a company's ability to
fund investing activities and meet its future debt service requirements.
Free cash flow is not a measure of financial performance under accounting
principles generally accepted in the United States and should not be
considered as an alternative to cash flows from operating, investing or
financing activities as an indicator of cash flows or as a measure of
liquidity. The following table reconciles net cash provided by operating
activities to free cash flow:

Twelve Months Ended December 31,
--------------------------------
2004 2003
-------------- ---------------
(in millions)

Net cash provided by operating activities....... $798.7 $662.8
Less: Capital expenditures..................... 176.1 174.6
------ ------
Free cash flow.................................. $622.6 $488.2
====== ======

7) Net income before special charges excludes the second quarter 2004 charges
associated with the acceleration of certain pension obligations in
connection with the CEO succession process and the refinancing of the
Company's bank debt and credit facility. Operating income before special
charge excludes the charge associated with the CEO succession process. Both
operating income and net income before special charges, including per
common share amounts, are presented because management believes they are
useful adjuncts to other measurements under accounting principles generally
accepted in the United States, including reported operating income and net
income since they are meaningful measures of the Company's on-going
operating performance and are on a basis consistent with prior reported
results. Operating income before special charge and net income before
special charges, including per common share amounts, are not measures of
financial performance under accounting principles generally accepted in the
United States and should not be considered as alternatives to reported
operating income and net income as an indicator of performance. The
following table reconciles operating income and net income before special
charges to reported results:

For the Twelve Months Ended December 31, 2004
---------------------------------------------------------------
(in millions, except per share amounts)

Special Charges Related to:
----------------------------
Acceleration
of Certain
Before Special Pension Debt
Charges Obligations Refinancing As Reported
-------------- ------------- ------------- --------------

Net revenues......................................... $5,126.6 $ - $ - $5,126.6

------------------------------------------------------------------------------------------------------------------

Operating income..................................... $ 901.5 $(10.3) $ - $ 891.2
Interest expense, net................................ (55.0) - (2.9) (57.9)

------------------------------------------------------------------------------------------------------------------

Income before taxes.................................. $ 848.3 $(10.3) $ (2.9) $ 835.1
Income tax expense (benefit)......................... 341.2 (4.1) (1.2) 335.9
-------- ------ ------ --------
Net income........................................... $ 507.1 $ (6.2) $ (1.7) $ 499.2
======== ====== ====== ========

------------------------------------------------------------------------------------------------------------------

Basic earnings per common share...................... $ 4.98 $(0.06) $(0.02) $ 4.90
Diluted earnings per common share.................... $ 4.77 $(0.06) $(0.02) $ 4.69

Diluted earnings per common share, before the
required change in accounting for the
Company's contingent convertible debentures(A).... $ 4.87

------------------------------------------------------------------------------------------------------------------

Operating income as a percentage of net revenues(B).. 17.6% 17.4%

------------------------------------------------------------------------------------------------------------------

(A) Calculated by dividing net income before special charges by the
weighted average common shares outstanding - diluted (before the
required change in accounting for the Company's contingent convertible
debentures) in footnote 1

(B) Calculated by dividing operating income by
net revenues

8) Before the impact of the accounting change for equity-based compensation,
the Company expects 2005 diluted earnings per common share to be between
$5.45 and $5.55, operating income to be between 18% and 19% of revenues and
cash from operations to approach $800 million. The Company has not
finalized what, if any, changes may be made to its equity compensation
plans in light of the accounting change, and therefore is not yet in a
position to quantify its impact. The Company expects to announce the
impact in connection with reporting its second quarter 2005
financial results. Assuming there are no changes to the Company's equity
compensation plans, and an adoption date of July 1, 2005 for the new
accounting standard, the Company estimates that the adoption of the new
accounting standard will reduce diluted earnings per common share by up to
$0.23 per share and operating income, as a percentage of revenues, by up to
approximately 1%. The impact on cash from operations of adopting the new
accounting standard cannot be estimated at this time.

9) In December 2004, the Company called for redemption all of its outstanding
contingent convertible debentures due November 2021. Under the terms of the
debentures, the holders of the debentures had an option to submit their
debentures for redemption at par plus accrued and unpaid interest or
convert their debentures into shares of the Company's common stock at a
conversion price of $87.50 per share. The outstanding principal of the
debentures at December 31, 2004 is classified as a current liability within
short-term borrowings and current portion of long-term debt on the
Company's consolidated balance sheet at December 31, 2004. As of January
18, 2005, the redemption was completed and $0.4 million of principal was
redeemed for cash and $249.6 million of principal was converted into
approximately 2.9 million shares of the Company's common stock.