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


                                  SCHEDULE 13G

                    UNDER THE SECURITIES EXCHANGE ACT OF 1934

                             CHOLESTECH CORPORATION
                                (Name of Issuer)

                                  COMMON STOCK
                         (Title of Class of Securities)

                                    170393102
                                 (CUSIP Number)

                                DECEMBER 31, 2002
             (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. 170393102                 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         1,166,636  (See Item 4)

     6.  SHARED VOTING POWER               0

     7.  SOLE DISPOSITIVE POWER    1,166,636  (See Item 4)

     8.  SHARED DISPOSITIVE POWER          0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         1,166,636  (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:  8.6%

12.  TYPE OF PERSON REPORTING: IA



CUSIP No. 170393102                 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         1,166,636  (See Item 4)

     6.  SHARED VOTING POWER               0

     7.  SOLE DISPOSITIVE POWER    1,166,636  (See Item 4)

     8.  SHARED DISPOSITIVE POWER          0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         1,166,636  (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:  8.6%

12.  TYPE OF PERSON REPORTING:  BD



CUSIP No. 170393102                 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         1,166,636  (See Item 4)

     6.  SHARED VOTING POWER               0

     7.  SOLE DISPOSITIVE POWER    1,166,636  (See Item 4)

     8.  SHARED DISPOSITIVE POWER          0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         1,166,636  (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:  8.6%

12.  TYPE OF PERSON REPORTING: HC



CUSIP No. 170393102                 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         1,166,636  (See Item 4)

     6.  SHARED VOTING POWER               0

     7.  SOLE DISPOSITIVE POWER    1,166,636  (See Item 4)

     8.  SHARED DISPOSITIVE POWER          0

 9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
         1,166,636  (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:  8.6%

12.  TYPE OF PERSON REPORTING:  HC



ITEM 1(a):   NAME OF ISSUER:  Cholestech Corporation

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

             3347 Investment Boulevard
             Hayward, CA  94545-3808

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:  170393102

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:  1,166,636

             (b)  Percent of class:  8.6%

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

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

                         WDR:  1,166,636 (indirect)
                         WRFSI:  1,166,636 (indirect)
                         WRI:  1,166,636 (indirect)
                         WRIMCO:  1,166,636 (direct)

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

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

                         WDR:  1,166,636 (indirect)
                         WRFSI:  1,166,636 (indirect)
                         WRI:  1,166,636 (indirect)
                         WRIMCO:  1,166,636 (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: [ ]

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:   February 14, 2003


                                 
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