<PAGE>

                                  EXHIBIT 99.1

Contacts:  Daniel J. Thomas                  Thomas E. Kiraly
           President and                     Executive Vice President and
           Chief Executive Officer           Chief Financia Officer
           (972) 364-8111                    (972) 364-8217


             CONCENTRA OPERATING CORPORATION ANNOUNCES CHANGES IN
                          BUSINESS SEGMENT REPORTING


     ADDISON, Texas, March 27, 2001 - Concentra Operating Corporation
("Concentra") today announced that it will change the way it reports its
business segment results during 2001 to improve the manner in which operating
results are disclosed in its financial statements.  Previously, Concentra
divided its financial results into "Health Services," "Cost Containment," and
"Field Case Management" segments.  Under the new approach, although the Health
Services segment will remain the same, Concentra's other segments will be
grouped to provide a "Network Services" segment and a "Care Management Services"
segment.  The Company believes this change will promote a better understanding
of the underlying nature of its operations by providing a more consistent
representation of similar business units within each of the two newly formed
segments.  Further, the Company believes that the enhanced segment reporting
will more effectively communicate Concentra's current operating environment and
business unit strategy.

     Commenting on the revised reporting approach, Daniel J. Thomas, President
and Chief Executive Officer, said, "I am pleased that our segment reporting will
provide more clarity to our investors as to the underlying nature of our primary
businesses.  We have increasingly been managing the Company in a manner that
differentiates between operations that seek savings from healthcare providers
and those that facilitate returning patients to work.  Our new segmentation will
more effectively reflect this distinction."  Thomas also noted that the Company
currently plans to make no changes to its internal operating structure in
connection with its introduction of this new financial statement segmentation
approach.

     Under the new segmentation, the composition of the Health Services segment
will remain the same.  The Health Services segment will continue to reflect the
Company's revenues and business operations that provide specialized injury and
occupational healthcare services to employers.  Through 224 nationwide health
centers, Health Services delivers primary and rehabilitative care, including the
diagnosis, treatment and management of work-related injuries and illnesses.
Health Services also provides a full complement of non-injury, employment-
related health services, including physical examinations, pre-placement
substance abuse testing, job-specific return to work evaluations and other
related programs.

     The new Network Services segment will reflect those businesses that involve
the review and repricing of provider bills and which are routinely compensated
based on the degree to which Concentra achieves savings for its clients. This
segment will include Concentra's preferred provider organization, provider bill
review business and out-of-network bill review operations.  This segment will
also include Concentra's first notice of loss operations.



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Concentra Announces Changes in Business Segment Reporting
Page 2
March 27, 2001

     Care Management Services will reflect the Company's professional services
aimed at curtailing the cost of workers' compensation and auto claims through
field case management, telephonic case management, independent medical exams and
utilization management.  These services are designed to maximize medical
improvement and, where appropriate, to expedite the return to work.  These
services also concentrate on monitoring the timing and appropriateness of
medical care.

     As a result of the above changes, effective January 1, 2001, the Company
will prospectively report segment performance on its Health Services, Network
Services and Care Management Services groups. Had these segments been reported
in this manner historically, the Company's Statements of Operations on a segment
basis would have been stated as follows:


<TABLE>
<CAPTION>
                                                                         Years Ended December 31,
                                                              --------------------------------------------
                                                                        2000           1999           1998
                                                              --------------------------------------------
<S>                                                                 <C>            <C>            <C>
Revenue:
  Health Services                                                   $399,660       $330,064       $259,481
  Network Services                                                   162,596        158,022        135,805
  Care Management Services                                           189,905        193,326        215,770
                                                              --------------------------------------------

                                                                     752,161        681,412        611,056
Gross profit:
  Health Services                                                     77,876         64,981         58,300
  Network Services                                                    61,855         62,288         54,431
  Care Management Services                                            19,006         19,654         29,028
                                                              --------------------------------------------
                                                                     158,737        146,923        141,759

General and administrative expenses                                   66,491         65,291         45,326
Amortization of intangibles                                           14,628         12,960          8,119
Non-recurring charges                                                     --         54,419         33,114
                                                              --------------------------------------------
Operating income                                                      77,618         14,253         55,200

Interest expense                                                      68,932         35,779         18,021
Interest income                                                         (803)        (2,900)        (4,659)
Loss on change in fair value of hedging arrangements                   9,586             --             --
Other, net                                                              (725)          (391)            44
                                                              --------------------------------------------

Income (loss) before income taxes and cumulative
 effect of accounting change                                             628        (18,235)        41,794
Provision for income taxes                                             4,362          8,269         19,308
                                                              --------------------------------------------

Income (loss) before cumulative effect of accounting change           (3,734)       (26,504)        22,486

Cumulative effect of accounting change, net of tax                     2,817             --             --
                                                              --------------------------------------------
Net income (loss)                                                   $ (6,551)      $(26,504)      $ 22,486
                                                              ============================================
</TABLE>


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Concentra Announces Changes in Business Segment Reporting
Page 3
March 27, 2001

<TABLE>
<CAPTION>
                                                                                Quarters Ended
                                                                                  (Unaudited)
                                                        ------------------------------------------------------------
                                                            March 31,       June 30,        Sept. 30,       Dec. 31,
                                                        ------------------------------------------------------------
<S>                                                       <C>           <C>             <C>              <C>
Revenue:
  Health Services                                            $ 94,260        $103,004         $105,696      $ 96,700
  Network Services                                             40,919          38,862           39,078        43,737
  Care Management Services                                     45,917          48,482           47,990        47,516
                                                        ------------------------------------------------------------
                                                              181,096         190,348          192,764       187,953
Gross profit:
  Health Services                                              17,265          22,891           23,397        14,323
  Network Services                                             15,472          13,933           13,274        19,176
  Care Management Services                                      4,117           6,296            5,682         2,911
                                                        ------------------------------------------------------------
                                                               36,854          43,120           42,353        36,410

General and administrative expenses                            16,919          16,246           16,149        17,177
Amortization of intangibles                                     3,566           3,658            3,689         3,715
                                                        ------------------------------------------------------------
Operating income                                               16,369          23,216           22,515        15,518

Interest expense                                               16,221          17,926           17,857        16,928
Interest income                                                   (80)           (331)            (104)         (288)
(Gain) loss on change in fair value of hedging
 arrangements                                                  (1,537)          2,483            1,818         6,822
Other, net                                                       (196)             73             (140)         (462)
                                                        ------------------------------------------------------------

Income (loss) before income taxes and cumulative
 effect of accounting change                                    1,961           3,065            3,084        (7,482)
Provision (benefit) for income taxes                              893           1,921            2,279          (731)
                                                        ------------------------------------------------------------

Income (loss) before cumulative effect of accounting
 change                                                         1,068           1,144              805        (6,751)
Cumulative effect of accounting change, net of tax                 --              --               --         2,817
                                                        ------------------------------------------------------------
Net income (loss)                                            $  1,068        $  1,144         $    805      $ (9,568)
                                                        ============================================================
</TABLE>

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Concentra Announces Changes in Business Segment Reporting
Page 4
March 27, 2001

     Concentra Operating Corporation, the successor to and a wholly-owned
subsidiary of Concentra Inc., is the comprehensive outsource solution for
containing healthcare and disability costs.  Serving the occupational, auto and
group healthcare markets, Concentra provides employers, insurers and payors with
a series of integrated services which include employment-related injury and
occupational health care, in-network and out-of-network medical claims review
and re-pricing, access to specialized preferred provider organizations, first
notice of loss services, case management and other cost containment services.

     This press release contains certain forward-looking statements, which the
Company is making in reliance on the safe harbor provisions of the Private
Securities Litigation Reform Act of 1995.  Investors are cautioned that all
forward-looking statements involve risks and uncertainties, and that the
Company's actual results may differ materially from the results discussed in the
forward-looking statements.  Factors that could cause or contribute to such
differences include, but are not limited to, the potential adverse impact of
governmental regulation on the Company's operations, interruption in its data
processing capabilities, operational financing and strategic risks related to
the Company's capital structure and growth strategy, possible fluctuations in
quarterly and annual operations, possible legal liability for adverse medical
consequences, competitive pressures, adverse changes in market conditions for
the Company's services, and dependence on key management personnel.  Additional
factors include those described in the Company's filings with the Securities and
Exchange Commission.




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