Perhaps the package msm (Multi-state Markov models in continuous time ) is interesting for you?
christian ----- Original Message ----- From: "Damon Wischik" <[EMAIL PROTECTED]> To: "R-Help" <[EMAIL PROTECTED]> Sent: Saturday, July 26, 2003 8:14 PM Subject: [R] A model for disease progression > > I would be grateful for advice about the following problem. It's not > directly R-related, but I'm hoping that R will help me analyse the > following data. > > I have a table which indicates the progression of a certain age-related > disease. At a certain point in time, a population was sampled; and I have > measurements for the age of each individual, and their disease stage. > (Disease stage is an ordered factor, none<A<B<C<D.) > > I hypothesize that the rate of disease-onset depends on age, but that > (once the disease has started) its rate of progression depends on the > current disease stage and not on age. > > I would like to plot the data in a sensible way, to let me see if this > hypothesis is reasonable, and to let me explore possible functional forms > for the two rates. > > I can see how to plot the rate of disease onset. I could, for example, > plot for each age the fraction of people who have acquired the disease by > that age. But I don't know how to visualize the rate of disease > progression. > > All suggestions (especially pointers to relevant literature or R packages) > gratefully received! > > Damon. > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
