topic Proc PHREG Multivariate analysis in Statistical Procedures https://communities.sas.com/t5/Statistical-Procedures/Proc-PHREG-Multivariate-analysis/m-p/110609#M5846 <HTML><HEAD></HEAD><BODY><P>Hi All,</P><P></P><P>i need to find the risk ratio using phreg model.</P><P></P><P>i have a dataset with&nbsp; lenth of tretment variable</P><P></P><P>i want to find the risk ratio for group (&lt;18 months Vs &gt;=24 months)&nbsp; And (18-24 Vs &gt;=24)</P><P></P><P>Can any one help me with an exampl</P><P></P><P>Thanks</P><P>Sam</P></BODY></HTML> Fri, 15 Feb 2013 15:34:00 GMT sam369 2013-02-15T15:34:00Z Proc PHREG Multivariate analysis https://communities.sas.com/t5/Statistical-Procedures/Proc-PHREG-Multivariate-analysis/m-p/110609#M5846 <HTML><HEAD></HEAD><BODY><P>Hi All,</P><P></P><P>i need to find the risk ratio using phreg model.</P><P></P><P>i have a dataset with&nbsp; lenth of tretment variable</P><P></P><P>i want to find the risk ratio for group (&lt;18 months Vs &gt;=24 months)&nbsp; And (18-24 Vs &gt;=24)</P><P></P><P>Can any one help me with an exampl</P><P></P><P>Thanks</P><P>Sam</P></BODY></HTML> Fri, 15 Feb 2013 15:34:00 GMT https://communities.sas.com/t5/Statistical-Procedures/Proc-PHREG-Multivariate-analysis/m-p/110609#M5846 sam369 2013-02-15T15:34:00Z Re: Proc PHREG Multivariate analysis https://communities.sas.com/t5/Statistical-Procedures/Proc-PHREG-Multivariate-analysis/m-p/110610#M5847 <HTML><HEAD></HEAD><BODY><P>You need to explain your situation more.</P><P></P><P>Also, an assumption of PHREG, or a Cox regression model, is proportional hazard over time. So that means that the 'risk ratio' (which I think is the hazard ratio) should be constant?</P><P></P><P>But its morning and coffee hasn't kicked in yet...</P></BODY></HTML> Fri, 15 Feb 2013 15:41:21 GMT https://communities.sas.com/t5/Statistical-Procedures/Proc-PHREG-Multivariate-analysis/m-p/110610#M5847 Reeza 2013-02-15T15:41:21Z