<PAGE>

                                                                     EXHIBIT 4.1

                          COUNTERSIGNED AND REGISTERED:
                               NATIONAL CITY BANK
                                (Cleveland, Ohio)

                          TRANSFER AGENT AND REGISTRAR
                                       By:
                              AUTHORIZED SIGNATURE
                                    DATATRAK

NUMBER
C-

                          DATATRAK INTERNATIONAL, INC.
                INCORPORATED UNDER THE LAWS OF THE STATE OF OHIO
                                 CUSIP 238134100
                                 SEE REVERSE FOR
                               CERTAIN DEFINITIONS

THIS CERTIFIES THAT

SPECIMEN

IS THE OWNER OF

        FULLY PAID AND NON-ASSESSABLE COMMON SHARES WITHOUT PAR VALUE OF
                          DATATRAK INTERNATIONAL, INC.

transferable on the books of the Corporation in person or by duly authorized
attorney upon surrender of this certificate properly endorsed. This certificate
and the shares represented hereby are issued and shall be held subject to the
express terms and provisions of the Articles of Incorporation of the Corporation
filed in the office of the Secretary of State of Ohio. This certificate is not
valid unless countersigned by a Transfer Agent and registered by a Registrar.

WITNESS the facsimile signatures of its duly authorized officers.

        Dated:                 DATATRAK INTERNATIONAL, INC.

        Terry C. Black                        /s/Jeffrey A. Green
        Vice President of Finance,                   President and
        Chief Financial Officer,          Chief Executive Officer
        Treasurer and Assistant Secretary

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                          DATATRAK INTERNATIONAL, INC.

      The following abbreviations when used in the inscription on the face of
      this certificate, shall be construed as though they were written out in
      full according to applicable laws or regulations:

<TABLE>
<CAPTION>
<S>                                     <C>
TEN COM - as tenants in common          UNIF TRANS MIN ACT - ___________  __________
                                                             (Cust)          (Minor)
TEN ENT - as tenants by the entireties                       under Uniform Transfers
                                                              to Minors Act ________
JT TEN  - as joint tenants with right of                                     (State)
          survivorship and not as tenants
          in common
</TABLE>

      Additional abbreviations may also be used though not in the above list.

      The Corporation will mail to the holder of record of the shares
      represented by this certificate (without charge to the holder) within five
      days after receipt of written request therefor a copy of the express
      terms, if any, of the shares represented by this certificate and a copy of
      the express terms, if any, of the other class or classes and series of
      shares, if any, which the Corporation is authorized to issue.

      FOR VALUE RECEIVED, _______ HEREBY SELL, ASSIGN AND TRANSFER UNTOPLEASE
      INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE


      __________________________________________________________________________
      __________________________________________________________________________
      __________________________________________________________ of the Shares
      represented by the within Certificate and do hereby irrevocably constitute
      and appoint_______________________________________________________________
      Attorney to transfer the said shares on the books of the within-named
      Corporation with full power of substitution in the premises.

      Dated ____________

           NOTICE:THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND
                  WITH THE NAME AS WRITTEN UPON THE FACE OF THE
               CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION
                     OR ENLARGEMENT, OR ANY CHANGE WHATEVER.

      SIGNATURE(S) GUARANTEED BY: ______________________________________________
      The Signature(s) should be guaranteed by an eligible guarantor institution
      (Banks, Stockholders, Savings and Loan Associations and Credit Unions),
      with membership in an approved signature guarantee medallion program
      pursuant to SEC Rule 17A d-15.

      This certificate also evidences and entitles the holder hereof to certain
      rights as set forth in a Rights Agreement between DataTRAK International,
      Inc. and National City Bank dated as of September 2, 1997 (the "Rights
      Agreement"), the terms of which are hereby incorporated herein by
      reference and a copy of which is on file at the principal executive
      offices of DataTRAK International, Inc. Under certain circumstances, as
      set forth in the Rights Agreement, such Rights will be evidenced by
      separate certificates and will no longer be evidenced by this certificate.
      DataTRAK International, Inc. will mail to the holder of this certificate a
      copy of the Rights Agreement without charge after receipt of a written
      request therefor. Under certain circumstances, as set forth in the Rights
      Agreement, Rights issued to any Person who becomes an Acquiring Person (as
      defined in the Rights Agreement) may become null and void.