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                                                                   EXHIBIT 3.1.2

                   CERTIFICATE OF DESIGNATION, PREFERENCES AND
                                    RIGHTS OF
                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK
                                       OF
                                 MEDIRISK, INC.

                         Pursuant to Section 151 of the
                        Delaware General Corporation Law


         Medirisk, Inc., a corporation organized under the laws of the State of
Delaware (the "Corporation"), hereby certifies that, pursuant to the authority
conferred upon the Board of Directors by the Certificate of Incorporation, as
amended, of the Corporation, the Board of Directors on July 29, 1998, adopted
the following resolution creating a series of 200,000 shares of Preferred Stock
designated as Series A Junior Participating Preferred Stock:

         RESOLVED, that pursuant to the authority granted to and vested in the
Board of Directors of this Corporation (the "Board") in accordance with the
provisions of its Certificate of Incorporation, as amended, a series of
Preferred Stock of the Corporation be and hereby is created, and that the
designation and amount thereof and the voting rights or powers, preferences and
relative, participating, optional and other special rights of the shares of such
series, and the qualifications, limitations or restrictions thereof are as
follows:


         1.       Series A Junior Participating Preferred Stock. There is hereby
established a series of Preferred Stock, par value $0.001 per share, of the
Corporation, and the designation and certain terms, powers, preferences and
other rights of the shares of such series, and certain qualifications,
limitations and restrictions thereon, are hereby fixed as follows:

                  (i)      The distinctive serial designation of this series
shall be "Series A Junior Participating Preferred Stock" (hereinafter called
"this Series"). Each share of this Series shall be identical in all with the
other shares of this Series except as to the dates from and after which
dividends thereon shall be cumulative.

                  (ii)     The number of shares in this Series shall initially
be 200,000, which number may from time to time be increased or decreased (but
not below the number then outstanding) by the Board of Directors. Shares of this
Series purchased by the Corporation shall be canceled and shall revert to
authorized but unissued shares of Preferred Stock undesignated as to series.
Shares of this Series may be issued in fractional shares, which fractional
shares shall entitle the holder, in proportion to such holder's fractional
share, to all rights of a holder of a whole share of this Series.

                  (iii)    The holders of full or fractional shares of this
Series shall be entitled to receive, when and as declared by the Board of
Directors, but only out of funds legally available therefor, dividends, (A) on
each date that dividends or other distributions (other than dividends or
distributions payable in Common Stock of the Corporation) are payable on or in
respect of Common Stock comprising part of the Reference Package (as defined
below), in an amount per whole share of this Series equal to the aggregate
amount of dividends or other distributions (other than dividends or
distributions payable in Common Stock of the Corporation) that would be payable
on such date to a holder of the Reference Package and (B) on the last day of
March, June, September and December in each year, in an amount per whole share
of this Series equal to the excess (if any) of $1.00 over the aggregate
dividends paid per whole share of this Series during the three-month period
ending on such last day. Each such dividend shall be paid to the holders of
record of shares of this Series on the date, not exceeding sixty days preceding
such dividend or distribution payment date, fixed for that purpose by the Board
of Directors in advance of payment of each particular



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dividend or distribution. Dividends on each full and each fractional share of
this Series shall be cumulative from the date such full or fractional share is
originally issued; provided that any such full or fractional share originally
issued after a dividend record date and on or prior to the dividend payment date
to which such record date relates shall not be entitled to receive the dividend
payable on such dividend payment date or any amount in respect of the period
from such original issuance to such dividend payment date.

         The term "Reference Package" shall initially mean 100 shares of Common
Stock, par value $0.001 per share ("Common Stock"), of the Corporation. In the
event the Corporation shall at any time (A) declare or pay a dividend on any
Common Stock payable in Common Stock, (B) subdivide any Common Stock or (C)
combine any Common Stock into a smaller number of shares, then and in each such
case the Reference Package after such event shall be the Common Stock that a
holder of the Reference Package immediately prior to such event would hold
thereafter as a result thereof.

         Holders of shares of this Series shall not be entitled to any
dividends, whether payable in cash, property or stock, in excess of full
cumulative dividends, as herein provided on this Series.

         So long as any shares of this Series are outstanding, no dividend
(other than a dividend in Common Stock or in any other stock ranking junior to
this Series as to dividends and upon liquidation) shall be declared or paid or
set aside for payment or other distribution declared or made upon the Common
Stock or upon any other stock ranking junior to this Series as to dividends or
upon liquidation, nor shall any Common Stock nor any other stock of the
Corporation ranking junior to or on a parity with this Series as to dividends or
upon liquidation be redeemed, purchased or otherwise acquired for any
consideration (or any moneys be paid to or made available for a sinking fund for
the redemption of any shares of any such stock) by the Corporation (except by
conversion into or exchange for stock of the Corporation ranking junior to this
Series as to dividends and upon liquidation), unless, in each case, the full
cumulative dividends (including the dividend to be due upon payment of such
dividend, distribution, redemption, purchase or other acquisition) on all
outstanding shares of this Series shall have been, or shall contemporaneously
be, paid.

                  (iv)     In the event of any merger, consolidation,
reclassification or other transaction in which the shares of Common Stock are
exchanged for or changed into other stock or securities, cash and/or any other
property, then in any such case the shares of this Series shall at the same time
be similarly exchanged or changed in an amount per whole share equal to the
aggregate amount of stock, securities, cash and/or any other property (payable
in kind), as the case may be, that a holder of the Reference Package would be
entitled to receive as a result of such transaction.

                  (v)      In the event of any liquidation, dissolution or
winding up of the affairs of the Corporation, whether voluntary or involuntary,
the holders of full and fractional shares of this Series shall be entitled,
before any distribution or payment is made on any date to the holders of the
Common Stock or any other stock of the Corporation ranking junior to this Series
upon liquidation, to be paid in full an amount per whole share of this Series
equal to the greater of (A) $1.00 or (B) the aggregate amount distributed or to
be distributed prior to such date in connection with such liquidation,
dissolution or winding up to a holder of the Reference Package (such greater
amount being hereinafter referred to as the "Liquidation Preference"), together
with accrued dividends to such distribution or payment date, whether or not
earned or declared. If such payment shall have been made in full to all holders
of shares of this Series, the holders of shares of this Series as such shall
have no right or claim to any of the remaining assets of the Corporation.

         In the event the assets of the Corporation available for distribution
to the holders of shares of this Series upon any liquidation, dissolution or
winding up of the Corporation, whether voluntary or involuntary, shall be
insufficient to pay in full all amounts to which such holders are entitled
pursuant to the first paragraph of this Section (v), no such distribution shall
be made on account of any shares of any other class or series of Preferred Stock
ranking on a parity with the shares of this Series upon such liquidation,
dissolution or winding up unless proportionate distributive amounts shall be
paid on account of the shares of


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this Series, ratably in proportion to the full distributable, amounts for which
holders of all such parity shares are respectively entitled upon such
liquidation, dissolution or winding up.

         Upon the liquidation, dissolution or winding up of the Corporation, the
holders of shares of this Series then outstanding shall be entitled to be paid
out of assets of the Corporation available for distribution to its stockholders
all amounts to which such holders are entitled pursuant to the first paragraph
of this Section (v) before any payment shall be made to the holders of Common
Stock or any other stock of the Corporation ranking junior upon liquidation to
this Series.

         For the purposes of this Section (v), the consolidation or merger of,
or binding share exchange by, the Corporation with any other corporation shall
not be deemed to constitute a liquidation, dissolution or winding up of the
corporation.

                  (vi)     The shares of this Series shall not be redeemable.

                  (vii)    In addition to any other vote or consent of
stockholders required by law or by the Certificate of Incorporation, as amended,
of the Corporation, each whole share of this Series shall, on any matter, vote
as a class with any other capital stock comprising part of the Reference Package
and voting on such matter and shall have the number of votes thereon that a
holder of the Reference Package would have.

         IN WITNESS WHEREOF, Medirisk, Inc. has caused this Certificate of
Designation to be executed as of August 21, 1998.


                                    MEDIRISK, INC.


                                    By:      /s/ Barry W. Burt
                                       -----------------------------------------
                                    Name:    Barry W. Burt
                                         ---------------------------------------
                                    Title:   Vice President & Secretary
                                          --------------------------------------



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