R help - Jun 2009 - How to assign fixed beta coefficients in lrm for external validation

Hi,
I am planning to externally validate a logistic prediction model in a new
cohort. Outcome is mortality. The betacoefficients were derived from a
previous published article. It seems not possible in R to assign fixed beta
coefficients to predictors like lrm (death ~
intercept+beta1*var1+beta2*var2...). How do i solve this problem?

Thank you in advance.

Joey L
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On Jun 23, 2009, at 6:28 AM, jeweetwel wrote:
>
> Hi,
> I am planning to externally validate a logistic prediction model in  
> a new
> cohort. Outcome is mortality. The betacoefficients were derived from a
> previous published article. It seems not possible in R to assign  
> fixed beta
> coefficients to predictors like lrm (death ~
> intercept+beta1*var1+beta2*var2...). How do i solve this problem?
There is an offset model component for features that are assumed fixed.

-- 

David Winsemius, MD
Heritage Laboratories
West Hartford, CT