SAS Support Communities

Your code includes the option PLOTS=(CUMHAZ), which means that you are only requesting the plot for the cumulative hazard function. See the documentation for the other plots that you can request.You can also browse the Examples section of the documentation to see if your plot appears in any of the examples. If not, see the doc for the OUTPUT statement and create an output data set that contains the statistic that you want.   To specify the placement of the knots, see the article "Regression with restricted cubic splines in SAS". It sounds like you might want the LIST option: such as  KNOTMETHOD=LIST(0, 6, 12, 24)     ... View more

Hi Ballardw, I am using the proc phreg for Cox regression model,  the time variable is "follow_timedx_yrs" (person-years), the case is "definicion11_1" (values 0 and 1) and the exposure are the dummies for lactationcat.   Below the code to run the unadjusted model and the output:  /*Unadjusted model*/ proc phreg data=diabetes2; model follow_timedx_yrs*definicion11_1(0) = lactationcat_1 lactationcat_2 lactationcat_3 lactationcat_4/rl; run;   Attached the output.   I see that there is a non-linear association, I mean I would expect to have decreased risk for diabetes for the longer duration of breastfeeding, but this is not the case.     Some time ago I run regression models with restricted cubic splines using the code of Dr. Rick Wicklin but now I don't know how to do it when using Cox regression models.   Thanks,  Monica   ... View more