help summout
-------------------------------------------------------------------------------

Title

    summout -- Comparative table of summary statistics


Syntax

        summout [varlist] [if] [in] [using filename], by(groupvar) [more
                 options]

    by prefix is allowed; see [D] by.


Description

    summout creates a table of summary statistics for the variables listed in
    varlist across the categories of the categorical variable groupvar.
    Output table can be copied and pasted into any worksheet using the "Copy
    Table" option of the right click menu.  In addition, it can be exported
    in ASCII format to the file indicated in filename.  This is useful for
    large tables or as part of .do files.

    For every variable in varlist, summout first makes a normality test
    across the categories of groupvar.  If the test concludes normality, then
    mean and standard deviation are calculated, and a hypothesis test is done
    using oneway.  If the test finds a non-normal distribution, then median,
    interquartile range and a Kruskal-Wallis test are shown instead.

    According to options, output table can have one or more of the following
    columns:

    - Variable name or variable label
    - nonparam, which is 0 if the tested variable has normal distribution and
        1 if otherwise
    - est: variable's estimate measure (mean or median) for specified
        category or total value
    - dis: variable's dispersion measure (sd, se or iqr) for specified
        category or total value
    - lb: variable's lower boundary of confidence interval for specified
        category or total value
    - ub: variable's upper boundary of confidence interval for specified
        category or total value
    - p value, indicating the p value of the corresponding hypothesis test

    summout needs user-written command mat2txt, please check if installed.


Options

        +------+
    ----+ Main +-------------------------------------------------------------

    by(groupvar) is required, it indicates the variable containing the
        categories for comparison.  groupvar must have at least two values or
        an error message will be shown.  Same error will be displayed if
        population selected with if or in arguments leaves groupvar with only
        one category.

    ignore causes summout to assume all variables as normal (use this at your
        own risk).

    se diplays standard error of the mean instead of standard deviation (for
        normally distributed variables only).

    ci calculates and displays confidence intervals instead of a dispersion
        measure.  Confidence intervals are calculated using ci or centile
        accordingly.  Option ci overrides se.

    level(#) sets confidence level; default is level(95).

    dp(#) specifies number of decimal places for estimate and dispersion
        measures; default is dp(2).

    nt() specifies normality test to be used: sk for Skewness and kurtosis
        test, ks for Kolmogorov-Smirnov test and sw for Shapiro-Wilk test.
        Default is nt(sw).

    nolabel omits variable labels and value labels on the output table.


Examples

    sysuse auto
    summout price mpg weight, by(foreign)
    summout price mpg weight, by(foreign) nt(sk)
    summout price mpg weight, by(foreign) nt(ks)
    summout price mpg weight, by(foreign) ignore
    summout price mpg weight, by(foreign) nolabel
    summout price mpg weight, by(foreign) se
    summout price mpg weight, by(foreign) dp(3)
    summout price mpg weight, by(foreign) ci level(99)
    summout price mpg weight using example.txt, by(rep78)


Acknowledgements

    Special thanks to Ian Watson (see inspirational command tabout) for his
    valuable programming advice and to Zumin Shi for his constructive
    feedback.


Author

    Andrés González Rangel
    MD, MSc Clinical Epidemiology
    Universidad Nacional de Colombia
    algonzalezr@unal.edu.co