st: What does -koopmani- output? odds ratios or risk ratios?

["Tiago V. Pereira" <tiago.pereira@incor.usp.br>]

Dear statalisters,

Working with -koopmani-, one types:

.  koopmani 36 40 16 80

and gets:


                 |            Event       |            Proportion
                 |       Yes          No  |     Total         Yes
-----------------+------------------------+----------------------
          Group1 |        36           4  |        40      0.9000
          Group2 |        16          64  |        80      0.2000
-----------------+------------------------+----------------------
           Total |        52          68  |       120      0.4333
                 |                        |
                 |      Point estimate    |  [95% Conf. Interval]
-----------------|------------------------+----------------------
      Odds Ratio |              4.5       |  2.939633    7.152252
-----------------------------------------------------------------


That estimate of 4.5 is actually the risk ratio, isn´t it? Or am I doing a
big confusion?

. cci 36 4 16 64

All the best,

Tiago






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