st: Fitting weibull to a survival curve

[Giulio Rizzoli <giulio.rizzoli@unipd.it>]

I have several survival curves from medical papers, describing the 
follow-up time of patients on the x axis and the % survival on the y axis.
I need to fit a weibull model to this curves to summarize them with 2 
parameters , a shape and a scale parameter.
How can be practically done in Stata.
I have to input the time variable and the % survival ?
It is possible to stset these data ?
How should the weibull command be written?
                                        Thanks for help
                            Giulio Rizzoli , Padova (italy)
Giulio Rizzoli MD FETCS
Cardiochirurgia Padova
tel. 049 821-2408
fax 049 821-2409
e-mail giulio.rizzoli@unipd.it
web: http.//web.tiscali.it/grizzoli

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