help for iciss
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Title

    iciss -- ICD-9 based Injury Severity Score


Version

    Version 3.0.

    ICDPIC Version 3.0 requires STATA 8.0 or higher.  ICDPIC Version 3.0 has
    been tested in STATA 10 and STATA 11, but the authors believe it should
    also work without incident in STATA 8 and STATA 9.  If you have any
    problems using ICDPIC Version 3.0 in STATA 8 or STATA 9, please inform
    the authors.

    ICDPIC Version 3.0 may be installed from within STATA using the ssc
    command.  If you installed a previous version of ICDPIC from the SSC
    archives website using the ssc command, we suggest that you first delete
    it by typing ssc uninstall icdpic followed by ssc install icdpic.
    Alternatively, you may use ssc install icdpic, replace.  See help for 
    ssc.

    If you installed any previous ICDPIC files obtained directly from the
    authors, please delete them ALL (.ado, .hlp and .dta files) to avoid any
    conflicts with ICDPIC 3.0 files.

    Please enter complete variable names in the ICDPIC Version 3.0 dialog
    boxes.  Do not use abbreviations.

    New to Version 3.0 is the addition of a dialog box (.dlg) file associated
    with each individual ICDPIC Version 3.0 program (.ado) file.  To access
    the ICDPIC dialog box, and all the ICDPIC programs, type: db icdpic.
    Typing icdpic, as in earlier versions, will still work, but ONLY with
    icdpic.  For example, to access the ICISS program directly, type: db
    iciss.  Typing iciss, as in previous versions, will produce an error.

    Fixed in ICDPIC Version 3.0 is the ability to use path\file names
    containing spaces.

    Fixed in ICDPIC Version 3.0 is the ability to run in STATA 11.0.

    Fixed in ICDPIC Version 3.0 is a bug that caused the triss program to
    crash if the rts variable was named anything other than "rts".

    New in ICDPIC Version 3.0 (trauma program only) is the ability to choose
    whether an AIS value of 6 automatically forces an ISS of 75 or to
    automatically have all AIS values of 6 changed to an AIS value of 5 and
    then have the ISS calculated normally.

    All dialog boxes in ICDPIC Version 3.0 have memory.  Each time a dialog
    box is opened within the same STATA session, it will remember the values
    last entered.

    All dialog boxes in ICDPIC Version 3.0 have the following buttons:

      OK executes the program and removes the dialog box from the screen.

      SUBMIT executes the program and leaves the dialog box on the screen.
             Note that if an error message is generated the dialog box may be
             minimized.

      CANCEL removes the dialog box from the screen and does nothing.
             Clicking on the close icon of the dialog box does the same
             thing.

      HELP leaves the dialog box on the screen and presents the program help
           file.  The HELP button has a question mark on it.

      COPY leaves the dialog box on the screen and copies the program command
           to the clipboard.

      RESET resets the values of the controls in the dialog box to their
            initial state, just as if the dialog box were invoked for the
            first time.  Each time a user invokes a dialog box, its controls
            will be filled in with the values the user last entered.  RESET
            restores the control values to their defaults.  The RESET button
            has an R on it.


Syntax

        db iciss

    The ICISS dialog box will open.  Follow the instructions.

                                      OR

        db icdpic

    The ICDPIC dialog box will open.  Choose ICISS and click OK or Submit.
    The ICISS dialog box will open.  Follow the instructions.


Description

    iciss calculates ICISS using both survival risk ratios (SRR's) and
    independent survival risk ratios (SRRi's).


                        ICISS= (SRR_1)(SRR_2)...(SRR_N)

                                      OR

                      ICISS = (SRRi_1)(SRRi_2)...(SRRi_N)


    where ICISS for SRR is defined as the product of all survival risk ratios
    (SRR's) for an individual patient's ICD-9-CM injury diagnosis codes
    (N-Codes).  Similarly, ICISS for SRRi is defined as the product of all
    independent survival risk ratios (SRRi's) for an individual patient's
    N-Codes.  See help for srr for more infomation on SRR's and SRRi's.


Options

    None


Remarks

    The user should first run srr or icdpic on his/her data to produce the
    necessary table of SRR and SRRi values.  See help for srr.

    The user's data must contain ICD-9-CM diagnosis codes.  Diagnosis codes
    in the user's data must be of type string.  A decimal point in the
    diagnosis codes is optional.  Diagnosis codes should have a width of 5 (6
    if a decimal point is present).  The diagnosis code prefix must be the
    same for all diagnosis codes and numbered sequentially starting with 1,
    for example, dx1...dxN.

    srr adds the following variables to a new copy of the user's data stored
    on disk:


        srr_1-srr_n: survival risk ratio for ICD-9-CM diagnosis codes 1..n
        srri_1-srri_n: independent survival risk ratio for ICD-9-CM diagnosis
            codes 1..n
        srrprod: ICISS (product of srr values for all N-Codes)
        srriprod: ICISS (product of srri values for all N-Codes)
        min_srr: minimum srr value amongst all N-Codes
        min_srri: minimum srri value amongst all N-Codes
        srr_cnt: number of srr values that were involved in computation of
            srrprod
        srri_cnt: number of srri values that were involved in computation of
            srriprod

   
    srr and srri variables for diagnosis codes that are not valid N-Codes
    will have missing values.  If there are no valid N-Codes, variables
    srrprod, srriprod, min_srr and min_srri will be missing and variables
    srr_cnt and srri_cnt will be 0.  If there are no valid N-Codes with an
    SRR, variables for srrprod and min_srr will have missing values and
    variable srr_cnt will be 0.  If there are no valid N-Codes with an SRRi,
    variables for srriprod and min_srri will have missing values and variable
    srri_cnt will be 0.

    srr and srri variables and variables srrprod, srriprod, min_srr and
    min_srri are rounded to the nearest 0.0001.  If any of these values are
    equal, or round to, 0.0000 or 1.0000 they are replaced with 0.0001 and
    0.9999 respectively.


Examples

    None


Authors

    David E. Clark, M.D.

        Maine Medical Center, Portland, Maine, USA
        University of Vermont College of Medicine, Burlington, Vermont, USA
        Harvard Injury Control Research Center, Harvard School of Public
            Health, Boston, Massachusetts, USA

        Correspondence to Dr. Clark,
        887 Congress Street, Portland ME 04102
        Email:  clarkd@mmc.org

    Turner M. Osler, M.D.

        University of Vermont College of Medicine, Burlington, Vermont, USA

    David R. Hahn

        Maine Medical Center, Portland, Maine, USA


References

    Osler T, Rutledge R, Deis J, Bedrick E. ICISS: An International
        Classification of Disease-9 based injury severity score.  J Trauma
        1996;41:380-386.


Also see

    help for srr

    help for icdpic

    help for iciss