https://communities.sas.com/t5/SAS-Procedures/Is-there-a-test-of-landmark-survival-in-a-SAS-procedure/m-p/875317#M82723 <P>Hi,</P><P>In proc LIFETEST it's possible to create confidence intervals for the survival function at a particular point in time (i.e. a landmark time point).&nbsp; Does LIFETEST or any other SAS procedure also perform a test of this?</P><P>&nbsp;</P><P>More detail: I'm trying to recreate equation 3 which is based on the log-log transformation in Klein 2007 "Analyzing survival curves at a fixed point in time" DOI: 10.1002/sim.2864&nbsp;&nbsp;</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" style="width: 492px;"><img src="https://communities.sas.com/t5/image/serverpage/image-id/83888i84DC802A28A1FD07/image-dimensions/492x128?v=v2" width="492" height="128" role="button" title="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" alt="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" /></span></P><P>where</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" style="width: 342px;"><img src="https://communities.sas.com/t5/image/serverpage/image-id/83889i8189F83EC35BE0F5/image-dimensions/342x200?v=v2" width="342" height="200" role="button" title="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" alt="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" /></span></P><P>Many thanks</P> Thu, 11 May 2023 18:10:49 GMT Ke4 2023-05-11T18:10:49Z https://communities.sas.com/t5/SAS-Procedures/Is-there-a-test-of-landmark-survival-in-a-SAS-procedure/m-p/875317#M82723 <P>Hi,</P><P>In proc LIFETEST it's possible to create confidence intervals for the survival function at a particular point in time (i.e. a landmark time point).&nbsp; Does LIFETEST or any other SAS procedure also perform a test of this?</P><P>&nbsp;</P><P>More detail: I'm trying to recreate equation 3 which is based on the log-log transformation in Klein 2007 "Analyzing survival curves at a fixed point in time" DOI: 10.1002/sim.2864&nbsp;&nbsp;</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" style="width: 492px;"><img src="https://communities.sas.com/t5/image/serverpage/image-id/83888i84DC802A28A1FD07/image-dimensions/492x128?v=v2" width="492" height="128" role="button" title="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" alt="2023-05-11 18_51_06-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" /></span></P><P>where</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" style="width: 342px;"><img src="https://communities.sas.com/t5/image/serverpage/image-id/83889i8189F83EC35BE0F5/image-dimensions/342x200?v=v2" width="342" height="200" role="button" title="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" alt="2023-05-11 18_54_35-Statistics in Medicine - 2007 - Klein - Analyzing survival curves at a fixed poi.png" /></span></P><P>Many thanks</P> Thu, 11 May 2023 18:10:49 GMT https://communities.sas.com/t5/SAS-Procedures/Is-there-a-test-of-landmark-survival-in-a-SAS-procedure/m-p/875317#M82723 Ke4 2023-05-11T18:10:49Z https://communities.sas.com/t5/SAS-Procedures/Is-there-a-test-of-landmark-survival-in-a-SAS-procedure/m-p/879054#M82756 OUTSURV data set will have the estimate and CI for all times. You find the closest time point prior to the time of interest. You can see the point estimates if you use the TIMELIST option and the OUTSURV will have the confidence intervals for the time points. Fri, 02 Jun 2023 15:50:00 GMT https://communities.sas.com/t5/SAS-Procedures/Is-there-a-test-of-landmark-survival-in-a-SAS-procedure/m-p/879054#M82756 Reeza 2023-06-02T15:50:00Z