<PAGE>   1
                                             
 
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                             ---------------------
                                  FORM 10-K/A
                                AMENDMENT NO. 1
 
<TABLE>
<S>              <S>
   (MARK ONE)
      [X]        ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                 THE SECURITIES EXCHANGE ACT OF 1934 (NO FEE REQUIRED,
                 EFFECTIVE OCTOBER 7, 1996).
                 For the fiscal year ended December 31, 1996
                                              OR
      [  ]       TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                 THE SECURITIES EXCHANGE ACT OF 1934 (NO FEE REQUIRED).
                 For the transition period from ____________ to ____________
</TABLE>
 
COMMISSION FILE NUMBER 000-22005
                             ---------------------
                                 MEDIRISK, INC.
             (Exact name of registrant as specified in its charter)
                             ---------------------
 
<TABLE>
<C>                                             <C>
                   DELAWARE                                       58-2256400
(State or other jurisdiction of incorporation)       (I.R.S. Employer Identification No.)
</TABLE>
 
                        TWO PIEDMONT CENTER, SUITE 400,
                           3565 PIEDMONT ROAD, N.E.,
                          ATLANTA, GEORGIA 30305-1502
          (Address of principal executive offices, including zip code)
                             ---------------------
Registrant's telephone number, including area code: (404) 364-6700
Securities registered pursuant to Section 12(b) of the Act:    NONE
Securities registered pursuant to Section 12(g) of the Act:    COMMON STOCK,
                                                               $0.001 PAR VALUE
                                                                     (Title of
                                                                     Class)
 
     Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.   Yes [ ]   No [X]
 
     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.   [X]
 
     Aggregate market value of the Common Stock of the Registrant held by
non-affiliates of the registrant (3,172,083 shares) on March 25, 1997:
$24,583,643.25.
 
     The number of shares of Common Stock of the Registrant outstanding as of
March 25, 1997 was 4,013,752 shares.
                      DOCUMENTS INCORPORATED BY REFERENCE:
 
     The information called for by Part III is incorporated by reference to the
definitive Proxy Statement for the Annual Meeting of Stockholders of the Company
to be held May 21, 1997, which will be filed not later than 120 days after
December 31, 1996.
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<PAGE>   2
 
AMENDMENT:
 
     The Registrant hereby amends its Annual Report on Form 10-K for the fiscal
year ended December 31, 1996, by adding Schedule II and the signature page of
the Registrant, its chief executive and principal accounting officers and its
directors as set forth below immediately following the Independent Auditors'
Report appearing on page 38.
<PAGE>   3
                                                                       
                                                                    SCHEDULE II
 
                         MEDIRISK INC. AND SUBSIDIARIES
 
                       VALUATION AND QUALIFYING ACCOUNTS
 
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<CAPTION>
                                                                ADDITIONS
                                                       ---------------------------
                                          BALANCE AT                    CHARGES TO
                                          BEGINNING      CHARGES TO     COSTS AND       NET        BALANCE AT
DESCRIPTION                               OF PERIOD    OTHER ACCOUNTS    EXPENSES    DEDUCTIONS   END OF PERIOD
-----------                               ----------   --------------   ----------   ----------   -------------
<S>                                       <C>          <C>              <C>          <C>          <C>
December 31, 1994
  Allowance for doubtful accounts.......      --               --             --         --              --
December 31, 1995
  Allowance for doubtful accounts.......      --               --             --         --              --
December 31, 1996
  Allowance for doubtful accounts.......      --           47,439(1)      50,000         --          97,439
</TABLE>
 
---------------
 
(1) Represents beginning balance in allowance for doubtful accounts of acquired
    company.
 
                                       
<PAGE>   4
                                                                         

 
                                   SIGNATURES
 
     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, on March 28, 1997.
 
                                          MEDIRISK, INC.
 
                                          By:    /s/ KENNETH M. GOINS, JR.
                                            ------------------------------------
                                                   Kenneth M. Goins, Jr.
                                             Executive Vice President and Chief
                                                      Financial Officer
 
                               POWER OF ATTORNEY
 
     KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Mark A. Kaiser and Kenneth M. Goins, Jr., jointly
and severally, his attorneys-in-fact, each with full power of substitution, for
him in any and all capacities, to sign any amendments to this Annual Report on
Form 10-K and to file the same, with exhibits thereto and other documents in
connection therewith, with the Securities and Exchange Commission, hereby
ratifying and confirming all that each of said attorneys-in-fact, or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report on Form 10-K has been signed by the following persons on behalf of the
Registrant in the capacities and on the dates indicated.
 
<TABLE>
<CAPTION>
                      SIGNATURE                                       TITLE                      DATE
                      ---------                                       -----                      ----
<C>                                                      <S>                                <C>
 
                 /s/ MARK A. KAISER                      Chairman, Chief Executive          March 28, 1997
-----------------------------------------------------      Officer, President (principal
                   Mark A. Kaiser                          executive officer) and
                                                           Director
 
              /s/ KENNETH M. GOINS, JR.                  Chief Financial Officer,           March 28, 1997
-----------------------------------------------------      Executive Vice President
                Kenneth M. Goins, Jr.                      (principal financial and
                                                           accounting officer)
 
                 /s/ KEITH O. COWAN                      Director                           March 28, 1997
-----------------------------------------------------
                   Keith O. Cowan
 
                 /s/ MICHAEL J. FINN                     Director                           March 28, 1997
-----------------------------------------------------
                   Michael J. Finn
 
           /s/ WILLIAM M. MCCLATCHEY, M.D.               Director                           March 28, 1997
-----------------------------------------------------
                William M. McClatchey
 
              /s/ JAMES K. MURRAY, III                   Director                           March 28, 1997
-----------------------------------------------------
                James K. Murray, III
 
                /s/ ROBERT P. PINKAS                     Director                           March 28, 1997
-----------------------------------------------------
                  Robert P. Pinkas
</TABLE>
 
                                      
<PAGE>   5
 
                                   SIGNATURES
 
     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this amendment to be signed
on its behalf by the undersigned, thereunto duly authorized, on May 9, 1997.
 
                                          MEDIRISK, INC.
 
                                          By:    /s/ KENNETH M. GOINS, JR.
                                            ------------------------------------
                                                   Kenneth M. Goins, Jr.
                                             Executive Vice President and Chief
                                                      Financial Officer
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, this
amendment has been signed by the following persons on behalf of the Registrant
in the capacities and on the dates indicated.
 
<TABLE>
<CAPTION>
                      SIGNATURE                                        TITLE                     DATE
                      ---------                                        -----                     ----
<C>                                                      <S>                                  <C>
 
                          *                              Chairman, Chief Executive Officer    May 9, 1997
-----------------------------------------------------      (principal executive officer)
                   Mark A. Kaiser                          and Director
 
                          *                              Chief Financial Officer,             May 9, 1997
-----------------------------------------------------      Executive Vice President
                Kenneth M. Goins, Jr.                      (principal financial and
                                                           accounting officer)
 
                          *                              Director                             May 9, 1997
-----------------------------------------------------
                   Keith O. Cowan
 
                          *                              Director                             May 9, 1997
-----------------------------------------------------
                   Michael J. Finn
 
                          *                              Director                             May 9, 1997
-----------------------------------------------------
             William M. McClatchey, M.D.
 
                          *                              Director                             May 9, 1997
-----------------------------------------------------
                James K. Murray, III
 
                          *                              Director                             May 9, 1997
-----------------------------------------------------
                  Robert P. Pinkas
 
           *By: /s/ KENNETH M. GOINS, JR.
   -----------------------------------------------
                Kenneth M. Goins, Jr.
                  Attorney-in-Fact
</TABLE>
 
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