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help for ^confsvy^ 
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Assessing confounding effects in survey studies 
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    ^confsvy^ yvar xvar,  [^con^(covlist) ^cat^(covlist) ^nog^raph 
		^b^ackward ^det^ail ^l^evel(#) ^co^ef graph_options]
        
^confsvy^ calculates the change in effect estimates such as odds ratio, 
after adjusting for a potential confounder using either "forward 
selection" or "backward deletion" strategies. 

^confsvy^ also calculates and graphs adjusted effect measures and 
their confidence intervals. The order of variables being selected is 
based on the "importance" (magnitude) of "change in estimate". 
  
Variables required
-------------------

    ^yvar^ -- dependent variable, binary variable for logistic or poisson 
        regression; survival time variable for Cox proportional hazards
        model.  

    ^xvar^ -- exposure of interest
         
Options 
--------
    ^con^ -- list of potential continuous confounding variables. 
    ^cat^ -- list of potential categorical confouding variables. 
    ^nog^graph -- suppresses graphs. By default, a graph is given.   
    ^b^ackward -- specifies selection strategy as "back deletion method", 
        otherwise, "forward selection" method is default.
    ^co^ef -- graphs regression coefficients instead of effect estimates 
        for graphs.
    ^det^ail -- gives details at each step. Default only gives a summary. 
    ^l^evel(#) -- specifies the confidence level, in percent, for 
	    calculation of confidence intervals (default=95%)      
    ^graph_options^ -- some options with ^graph^ are allowed; see help 
        @graph@.

Examples
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 .  ^confsvy dead ab_uria, con(sbp weight) cat(sex agegroup)^
        Calculates and graphs crude and adjusted odds ratios using
        ^svylogit^ with a forward selection approach. 
        
 .  ^confsvy dead ab_uria, con(weight sbp) cat(sex agegroup) detail^
        Calculates and graphs crude and adjusted odds ratios using 
        ^svylogit^. Details in each step are given.

Author
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    Zhiqiang Wang
    Menzies School of Health Research, Darwin, Australia
    wang@@menzies.su.edu.au
