st: regression using eform

[Tina Hernandez-Boussard <boussard@stanford.edu>]

Hi,

I have a question regarding a regression model that I am running.  I  
am looking at predictors for a variable slope, which is growth of a  
tumor per day.  I have ran this model and using

sw, pr(.2):regress slope smoker exercise bmi , eform(odds)

I have reran the model, only multiplying the slope by 365.25 to get  
the growth per year.  I did not think that this would change  
anything, yet it changes the odds ratios.  I still get the same  
prob>f, r-squared, and adjusted r-squared.  However, model and  
residual ss, df, and ms are different.

Can someone please explain why my odds ratios are changing, yet the t  
and P>|t| are not?

First model:
------------------------------------------------------------------------ 
---
       slope |       odds   Std. Err.      t    P>|t|     [95% Conf.  
Interval]
------------- 
+----------------------------------------------------------------
    exercise |   1.000341   .0001396     2.45   0.017      
1.000062     1.00062
         bmi |   .9999843   9.47e-06    -1.66   0.102     . 
9999653    1.000003
      smoker |   1.000748   .0003167     2.36   0.021      
1.000116    1.001382

Model with slope*365.25:

------------------------------------------------------------------------ 
------
      growth |       odds   Std. Err.      t    P>|t|     [95% Conf.  
Interval]
------------- 
+----------------------------------------------------------------
   exercise  |   1.132765   .0577325     2.45   0.017      
1.023043    1.254254
         bmi |   .9942751   .0034406    -1.66   0.102     . 
9874212    1.001177
      smoker |   1.314259   .1519301     2.36   0.021      
1.043092    1.655921


Thanks,

Tina 
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