st: noninteger frequency weights in stset

["Galezewska P.B." <pbg1e11@soton.ac.uk>]

Hello, 

I am having problems with including noninteger weights in "stset" command. I am using stata 12.1 for windows. 

I've been trying to apply fweight in stset command but got stata response "may not use noninteger frequency weights". I need to include weights for calculating confidence intervals for Kaplan-Meier estimates (sts list). However, if I use a multiplication factor in order to get rid of the noninteger numbers for my weights, e.g. 100 or 1000, the sample size increases and confidence intervals decrease which mess up my results. I am trying to compare the confidence intervals for estimates of two groups at a certain time (60 months). Changing the multiplication factor, changes the significance of the differences between the estimates. 
Thus, I would very appreciate if someone could explain how to use the noninteger weights in the stset command. (Stset with pweight does not give me the confidence intervals at all)


Best wishes,

Paulina Galezewska




*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/