Sounds correct (though I can only certify the parts of the message in
English or Stata)
-- Maarten
--- roland andersson <[email protected]> wrote:
> Maarten
>
> Det er jo glimrende o dejlig
>
> Just to assure I have understood. In this model I keep age 10-19 and
> non-perforated appendicitis (the largest groups) as reference level
> so
> I do not bother with mean centering with age.
>
>
> lnLOS exp(b) Std. Err. t P>t
> [95% Conf. Interval]
>
> lapscopy 1.015229 .0069404 2.21 0.027 1.001716
> 1.028924
> _Iappdgn2_1 1.854565 .0133561 85.76 0.000 1.828571
> 1.880929
> _Iappdgn2_3 1.172527 .0139403 13.39 0.000 1.14552
> 1.200171
> _Ialderkat_0 1.113349 .0124712 9.59 0.000 1.089172
> 1.138063
> _Ialderka~20 .9669727 .0081023 -4.01 0.000 .9512217
> .9829846
> _Ialderka~30 1.013716 .0091096 1.52 0.130 .9960177
> 1.03173
> _Ialderka~40 1.074382 .0115025 6.70 0.000 1.052072
> 1.097165
> _Ialderka~50 1.181179 .0134386 14.64 0.000 1.15513
> 1.207815
> _Ialderka~60 1.309059 .0192205 18.34 0.000 1.271924
> 1.347279
> _Ialderka~70 1.685401 .0312085 28.19 0.000 1.625328
> 1.747694
> _Ialderka~80 2.303874 .0611701 31.43 0.000 2.187045
> 2.426943
> prepermalign 1.190686 .027653 7.51 0.000 1.137701
> 1.24614
> precardios~s 1.024731 .0266026 0.94 0.347 .9738935
> 1.078222
> preperlung~d 1.076669 .0182661 4.35 0.000 1.041456
> 1.113073
> preperhype~i 1.024272 .0208447 1.18 0.239 .9842196
> 1.065954
> preperhjar~t 1.293909 .0480737 6.94 0.000 1.203033
> 1.391651
> prepernjur~t 1.050412 .0516992 1.00 0.318 .953814
> 1.156792
> preperdiab~s 1.168423 .0287019 6.34 0.000 1.113499
> 1.226055
> cons 1.858693 .0106446 108.24 0.000 1.837946
> 1.879675
>
> And here I calculate the effect of laparoscopy
>
> . nlcom exp((_b[cons]+ _b[lapscopy]) - exp((_b[cons])))
>
> _nl_1: exp((_b[cons]+ _b[lapscopy]) - exp((_b[cons])))
>
>
> vtidln Coef. Std. Err. t P>t [95% Conf. Interval]
>
> _nl_1 .2941382 .0027509 106.92 0.000 .2887463
> .2995302
>
> ie open appendectomy in nonperforated patients age 10-19 have a
> geometric mean LOS of 1.86 (95% CI 1.83-1.88) days after adjustment
> for comorbidity and lapscopy patients have 0.29 (95% CI 0.28-0.30)
> days longer LOS.
>
> Correct?
>
> Greetings o stort tack
>
> Roland Andersson
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room N515
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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