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help for ^stquant^                                      (V.C. 1999)
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Quantiles Estimation and Confidence Intervals for Survival Time
---------------------------------------------------------------

    ^stquant^ [^if^ exp] [^in^ range] [^,^ ^by(^varname^)^ ^l^evel^(^#^)^
^q^uant^(^#^)^ 

^stquant^ is for use with survival-time data; see help @st@.  You must
^stset^ your data before using this command; see help @stset@.


Description
-----------

^stquant^ presents point and interval estimates of quantiles for survival
time. Confidence intervals are obtained by two methods: large sample normal
distribution of the estimated quantile and that one proposed by Brookmeyer
and Crowley. Both show limits. The first one has not yet been fully studied
and I noted some incosistencies for small samples in the right tail of the
survivorship function. For the latter one  Authors recommend that this
interval be used when there are no tied survival times. 


Options
-------

^by(^varname^)^ requests separate estimates for each group marked by having
   equal values of the variables in varname along with an overall total.    
   Varname may contain just one variable which may be string or numeric.

^level(^#^)^ specifies the confidence level, in percent, for the survival
    time. Default is 95; see help @level@.

^q^uant^(^#^)^ sets the quantile of survival time estimated. Default is 50.
    Values allowed are from 5 to 94.



Examples
--------

 . ^stquant, by(hercoc) l(80) q(75)^


Also see
--------

On-line:  help for @stsum@, @sts@.


Reference
---------

D.W. Hosmer  S. Lemeshow (1999): Applied Surival Analysiys - pag. 49-52
