UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549


                                 SCHEDULE 13G

                  UNDER THE SECURITIES EXCHANGE ACT OF 1934

                               AMENDMENT NO. 4*

                                 CERNER CORP.
                               (Name of Issuer)

                                 COMMON STOCK
                        (Title of Class of Securities)

                                  156782104
                                (CUSIP Number)

                              DECEMBER 31, 2001
           (Date of Event Which Requires Filing of this Statement)

CHECK THE APPROPRIATE BOX TO DESIGNATE THE RULE PURSUANT TO WHICH THIS
SCHEDULE IS FILED:

                              [X] RULE 13d-1(b)

                              [ ] RULE 13d-1(c)

                              [ ] RULE 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).





CUSIP No. 156782104                13G

 1.  NAME OF REPORTING PERSON (S.S. or I.R.S. Identification No. of Above
     Person)

     Waddell & Reed Investment Management Company  Tax ID No. 48-1106973

 2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:

     (a)    [ ]
     (b)    [ ]

 3.  SEC USE ONLY

 4.  CITIZENSHIP OR PLACE OF ORGANIZATION:   Kansas

 NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

     5.  SOLE VOTING POWER               767,600  (See Item 4)

     6.  SHARED VOTING POWER             0

     7.  SOLE DISPOSITIVE POWER          767,600  (See Item 4)

     8.  SHARED DISPOSITIVE POWER        0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         767,600  (See Item 4)

10.  CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES:
         [ ]

11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9:  0.2%

12.  TYPE OF PERSON REPORTING:  IA







CUSIP No. 156782104                13G

 1.  NAME OF REPORTING PERSON (S.S. or I.R.S. Identification No. of Above
     Person)

     Waddell & Reed, Inc.  Tax ID No. 43-1235675

 2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:

     (a)    [ ]
     (b)    [ ]

 3.  SEC USE ONLY

 4.  CITIZENSHIP OR PLACE OF ORGANIZATION:   Delaware

 NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

     5.  SOLE VOTING POWER               767,600  (See Item 4)

     6.  SHARED VOTING POWER             0

     7.  SOLE DISPOSITIVE POWER          767,600  (See Item 4)

     8.  SHARED DISPOSITIVE POWER        0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         767,600  (See Item 4)

10.  CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES:
         [ ]

11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9:  0.2%

12.  TYPE OF PERSON REPORTING:  BD





CUSIP No. 156782104                 13G

 1.  NAME OF REPORTING PERSON (S.S. or I.R.S. Identification No. of Above
     Person)

     Waddell & Reed Financial Services, Inc.  Tax ID No. 43-1414157

 2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:

     (a)    [ ]
     (b)    [ ]

 3.  SEC USE ONLY

 4.  CITIZENSHIP OR PLACE OF ORGANIZATION:   Missouri

 NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

     5.  SOLE VOTING POWER               767,600  (See Item 4)

     6.  SHARED VOTING POWER             0

     7.  SOLE DISPOSITIVE POWER          767,600  (See Item 4)

     8.  SHARED DISPOSITIVE POWER        0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         767,600  (See Item 4)

10.  CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES:
         [ ]

11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9:  0.2%

12.  TYPE OF PERSON REPORTING:  HC





CUSIP No. 156782104                13G

 1.  NAME OF REPORTING PERSON (S.S. or I.R.S. Identification No. of Above
     Person)

     Waddell & Reed Financial, Inc.  Tax ID No. 51-0261715

 2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:

     (a)    [ ]
     (b)    [ ]

 3.  SEC USE ONLY

 4.  CITIZENSHIP OR PLACE OF ORGANIZATION:   Delaware

 NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

     5.  SOLE VOTING POWER               767,600  (See Item 4)

     6.  SHARED VOTING POWER             0

     7.  SOLE DISPOSITIVE POWER          767,600  (See Item 4)

     8.  SHARED DISPOSITIVE POWER        0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         767,600  (See Item 4)

10.  CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES:
         [ ]

11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9:  0.2%

12.  TYPE OF PERSON REPORTING:  HC





ITEM 1(a):    NAME OF ISSUER:  Cerner Corp.

ITEM 1(b):    ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:

              2800 Rockcreek Pkwy
              Suite 601
              Kansas City, MO 64117

ITEM 2(a):    NAME OF PERSON FILING:

              (i)      Waddell & Reed Financial, Inc.
              (ii)     Waddell & Reed Financial Services, Inc.
              (iii)    Waddell & Reed, Inc.
              (iv)     Waddell & Reed Investment Management Company

ITEM 2(b):    ADDRESS OF PRINCIPAL BUSINESS OFFICE:

              (i)-(iv):      6300 Lamar Avenue
                             Overland Park, KS  66202

ITEM 2(c):    CITIZENSHIP:

              (i), (iii): Delaware
              (ii):  Missouri
              (iv):  Kansas

ITEM 2(d):    TITLE OF CLASS OF SECURITIES:  Common Stock

ITEM 2(e):    CUSIP NUMBER:  156782104

ITEM 3:       The reporting person is:

              (i)    Waddell & Reed Financial, Inc., a parent holding
                     company in accordance with Reg.
                     240.13d-1(b)(1)(ii)(G);
              (ii)   Waddell & Reed Financial Services, Inc., a parent
                     holding company in accordance with Reg.
                     240.13d-1(b)(1)(ii)(G);
              (iii)  Waddell & Reed, Inc., a broker-dealer in accordance
                     with Reg. 240.13d-1(b)(1)(ii)(A); and
              (iv)   Waddell & Reed Investment Management Company, an
                     investment advisor in accordance with Reg.
                     240.13d-1(b)(1)(ii)(E).

ITEM 4:       OWNERSHIP

              The securities reported on herein are beneficially owned by one
or more open-end investment companies or other managed accounts which are
advised or sub-advised by Waddell & Reed Investment Management Company
("WRIMCO"), an investment advisory subsidiary of



Waddell & Reed, Inc. ("WRI"). WRI is a broker-dealer and underwriting
subsidiary of Waddell & Reed Financial Services, Inc., a parent holding
company ("WRFSI"). In turn, WRFSI is a subsidiary of Waddell & Reed
Financial, Inc., a publicly traded company ("WDR"). The investment advisory
contracts grant WRIMCO all investment and/or voting power over securities
owned by such advisory clients. The investment sub-advisory contracts grant
WRIMCO investment power over securities owned by such sub-advisory clients
and, in most cases, voting power. Any investment restriction of a
sub-advisory contract does not restrict investment discretion or power in a
material manner. Therefore, WRIMCO may be deemed the beneficial owner of the
securities covered by this statement under Rule 13d-3 of the Securities
Exchange Act of 1934 (the "1934 Act").

              WRIMCO, WRI, WRFSI and WDR are of the view that they are not
acting as a "group" for purposes of Section 13(d) under the 1934 Act.
Indirect "beneficial ownership" is attributed to the respective parent
companies solely because of the parent companies' control relationship to
WRIMCO.

              (a)    Amount beneficially owned:  767,600

              (b)    Percent of class:  0.2%

              (c)    Number of shares as to which the person has:

                     (i)    Sole voting power to vote or to direct the vote:

                            WDR:  767,600 (indirect)
                            WRFSI:  767,600 (indirect)
                            WRI:  767,600 (indirect)
                            WRIMCO:  767,600 (direct)

                     (ii)   Shared power to vote or to direct the vote:  0

                     (iii)  Sole power to dispose or to direct the disposition
                            of:

                            WDR:  767,600 (indirect)
                            WRFSI:  767,600 (indirect)
                            WRI:  767,600 (indirect)
                            WRIMCO:  767,600 (direct)

                     (iv)   Shared power to dispose or to direct the disposition
                            of:  0

ITEM 5:       OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:

              If this statement is being filed to report the fact that as of
the date hereof the reporting person has ceased to be the beneficial owner of
more than 5 percent of the class of securities, check the following: [X]



ITEM 6:       OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON:

              The clients of WRIMCO, including investment companies
registered under the Investment Company Act of 1940 and other managed
accounts, have the right to receive dividends from as well as the proceeds
from the sale of such securities.

ITEM 7:       IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
              THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY:

              See Attached Exhibit 2.

ITEM 8:       IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP:

              Not Applicable.

ITEM 9:       NOTICE OF DISSOLUTION OF GROUP:

              Not Applicable.




Item 10:      Certification:

              By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired and are held in the
ordinary course of business and were not acquired and are not held for the
purpose of or with the effect of changing or influencing the control of the
issuer of the securities and were not acquired and are not held in connection
with or as a participant in any transaction having that purpose or effect.

                                    SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.

Dated:  January 7, 2002


                                     
Waddell & Reed Financial, Inc.           Waddell & Reed Financial Services, Inc.

By: /s/ Daniel C. Schulte                By: /s/ Wendy J. Hills

Name:   Daniel C. Schulte                Name:   Wendy J. Hills
Title:  Vice President                   Title:  Attorney-In-Fact


Waddell & Reed, Inc.                     Waddell & Reed Investment Management Company

By: /s/ Wendy J. Hills                   By: /s/ Wendy J. Hills

Name:   Wendy J. Hills                   Name:   Wendy J. Hills
Title:  Attorney-In-Fact                 Title:  Attorney-In-Fact





                                  EXHIBIT INDEX


Exhibit
   No.         Description
           

    1          Joint Filing Agreement

    2          Identification and Classification of the Subsidiary Which Acquired the Security Being
               Reported on by the Parent Holding Company

    3          Power of Attorney