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                                                                  EXHIBIT (e)(5)
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                                   AMENDMENT

          This AMENDMENT is made as of the 4th day of May, 2000 and amends the
Lease Agreement entered into as of the 1/st/ day of August, 1999 by and between
ShopKo Stores, Inc., a Wisconsin corporation, whose mailing address is P.O. Box
19060, Green Bay, Wisconsin 54307-9060 ("Lessor") and ProVantage Health
Services, Inc., a Delaware corporation, whose mailing address is N19 W24130
Riverwood Drive, Waukesha, Wisconsin 53188 ("Lessee").

          WHEREAS, Lessor and Lessee desire to amend certain provisions of the
Lease Agreement in connection with the transactions contemplated by that certain
Agreement and Plan of Merger among Merck & Co., Inc., a New Jersey corporation,
PV Acquisition Corp., a Delaware corporation and Lessee, dated as of May 4,
2000.

          NOW, THEREFORE, in consideration of the mutual premises set forth
herein and other good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledges, the parties do hereby agree as follows:

     1.   Section 2 of the Lease is hereby deleted in its entirety and replaced
          by the following:

          A.   Initial Term.  The initial term of this Lease shall expire two
               ------------
               (2) years from the date on which Lessor ceases to beneficially
               own at least a majority of the outstanding common stock of Lessee
               (the "Change of Control Date"). At the end of the initial term,
               Lessee may (i) terminate this Lease, (ii) purchase the Premises
               in accordance with Section 4 or (iii) extend the term of the
               Lease in accordance with Section 2B. Until the end of the initial
               term, which shall be amended as set forth below, the annual Rent
               (as defined in the Lease Agreement) shall remain at $200,000.00,
               payable in equal monthly installments of $16,666.67, as provided
               in Section 3 of the Lease Agreement.

          B.   Options to Extend.  Provided that Lessee is not then in default
               -----------------
               under this Lease at the time of exercise of the option and that
               Lessee continues in possession of the Premises pursuant to the
               terms of the Lease at such time, Lessee shall have the option to
               extend the term of this Lease for an additional term of two (2)
               years (an "Extended Term"), upon the terms and conditions set
               forth herein (other than the option to extend), subject to any
               increase in Base Rent as set forth in Section 4C and commencing
               upon the expiration of the initial term. If Lessee desires to
               exercise its option to extend, Lessee shall give written notice
               to Lessor not later than one hundred eighty (180) days prior to
               the expiration of the initial term. Any reference in the Lease to
               the "term" of the Lease shall be deemed

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               to include the initial term (subject to the provisions of the
               last sentence of Section 2.A. above) and the Extended Term for
               which Lessee has exercised the option granted under this Section,
               unless it is expressly provided otherwise.

     2.   Section 4 of the Lease Agreement is hereby deleted in its entirety and
          replaced by the following:

          At the end of the initial term of this Lease, Lessee shall have the
right and the option to purchase the Premises in accordance with this Section 4.

          A.   Determination of Fair market Value and Rent.  Not later than one
               -------------------------------------------
               hundred eighty (180) days prior to the end of the initial term,
               Lessee shall give Lessor written notice thereof indicating in
               such notice whether Lessee desires to exercise its option to
               purchase the Premises. Within thirty (30) days of its receipt of
               such notice, Lessor shall notify Lessee in writing what it
               considers to be (i) the Fair Market Value of the Premises and
               (ii) the Fair Market Rent for the Premises. For purposes of this
               Agreement, the "Fair Market Value" shall mean the highest
               purchase price a third party would be willing to pay for the
               Premises in an arms length transaction and "Fair Market Rent"
               shall mean the highest annual rental rate a third party would be
               willing to pay for the Premises in an arms length transaction. If
               Lessee objects to the Fair Market Value or Fair Market Rent
               delivered by Lessor, Lessee shall notify Lessor within thirty
               (30) days after receipt of Lessor's notice to Lessee, together
               with an appraisal, from an appraiser bearing MAI designation, as
               to the such appraiser's conclusions regarding Fair Market Value
               and/or Fair Market Rent. If Lessee does not object within such
               time, the Fair Market Value and the Fair Market Rent shall be as
               specified in Lessor's notice. If Lessee notifies Lessor within
               such time of an objection, Lessor, at its sole option, but within
               twenty (20) days of Lessor's receipt of such objection, may
               accept the conclusions of Lessee's appraiser or appoint another
               appraiser, in which case the two appraisers shall promptly meet
               and attempt to agree on the disputed amount or amounts. If they
               are able to agree, they shall jointly notify each of the parties
               of the conclusions they have reached, and the amount so agreed
               upon shall be deemed the Fair Market Value and Fair Market Rent,
               as applicable. If they are unable to agree within twenty (20)
               days of the appointment by Lessor, the average of the appraisers'
               final conclusions with respect to any disputed amount shall be
               deemed the Fair Market Value and Fair Market Rent, as applicable.

          B.   Option to Purchase.  Within thirty (30) days after final
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               determination of the Fair Market Value, Lessee shall give Lessor
               written notice if it desires to exercise its option to purchase
               the Premises. If Lessee timely notifies Lessor that it is
               exercising the option hereunder, the parties shall

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               reasonably agree on and promptly enter into a Purchase Agreement
               with respect to the Premises, with a purchase price equal to the
               Fair Market Value (as determined in accordance with Section 4A),
               upon commercially reasonable terms and conditions, and with a
               closing date to be no later than sixty (60) days after final
               determination of the Fair Market Value.

          C.   Base Rent Increases.  If Lessee exercises its option to extend
               -------------------
               the term of this Lease pursuant to Section 2B, then the annual
               Base Rent due under this Lease shall automatically be adjusted as
               of the first day of the Extended Term to reflect the Fair Market
               Rent (as determined in accordance with Section 4A). During the
               determination of the Fair Market Rent as set forth in Section 4A,
               Lessee shall continue to pay the then current Base Rent as it
               becomes due; provided, however, that upon final determination of
               the Fair Market Rent, Lessee shall pay to Lessor within thirty
               (30) days, any Base Rent amount that may be in arrears due to the
               retroactive adjustment of the annual Base Rent back to the first
               day of the Extended Term.

     3.   Section 9 of the Lease Agreement is hereby deleted in its entirety and
          replaced by the following:

          Lessee shall not make any additions, alterations or improvements in or
          to the Building or the Premises at any time during the initial term of
          the Lease or the Extended Term, if any, without the prior written
          consent of Lessor, such consent not to be unreasonably withheld.

     4.   Section 16 of the Lease Agreement is hereby deleted in its entirety
          and replaced by the following:

          Lessee shall not alter, remove or replace any signs currently on the
          Premises or the Building, or install or affix any additional signs on
          the Premises or the Building, without the prior written consent of
          Lessor, such consent not to be unreasonably withheld.

     5.   Section 24A of the Lease Agreement is hereby deleted in its entirety
          and replaced by the following:

          A.   Lessee shall not assign, sell, mortgage, pledge or in any manner
               transfer this Lease or any right, title, or interest of Lessee
               hereunder, by operation of law or otherwise, or any part or parts
               thereof, nor may Lessee sublet all or any portion of the
               Premises, without the prior written consent of Lessor (which
               consent shall not be unreasonably withheld). If consent is
               granted, Lessee shall remain fully and directly responsible for
               all covenants and obligations hereunder during the entire Lease
               Term.

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     6.   Each reference in the Lease to "this Lease" or the like shall be
          deemed a reference to the Lease as amended by this Amendment.

     7.   Except as expressly modified or amended herein, the Lease shall
          continue in effect and shall continue to bind the parties hereto.

     8.   This Amendment shall be effective when executed by Lessor and Lessee
          and upon the Change of Control Date.

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     IN WITNESS WHEREOF, this Amendment has been executed and delivered on the
date first written above.


                              SHOPKO STORES, INC.


                              /s/ Richard D. Schepp
                              ----------------------------------
                              Name:  Richard D. Schepp
                              Title: Senior Vice President,
                                     General Counsel/Secretary


                              PV ACQUISITION CORP.


                              /s/ Judy C. Lewent
                              ----------------------------------
                              Name:  Judy C. Lewent
                              Title: President

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