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    <title>topic Trend Test in Lifetest Proc in SAS Procedures</title>
    <link>https://communities.sas.com/t5/SAS-Procedures/Trend-Test-in-Lifetest-Proc/m-p/26361#M6016</link>
    <description>Hey all,&lt;BR /&gt;
I am very new to SAS, long time JMP and R user, but I need to use it to perform a trend test for a class I am taking.  I am using the following code to test for the trend:&lt;BR /&gt;
&lt;BR /&gt;
proc lifetest data=rats;&lt;BR /&gt;
time Time*Censor(0);&lt;BR /&gt;
strata Untreated Radiated RadiatedBPA /Trend test=(all);&lt;BR /&gt;
run;&lt;BR /&gt;
&lt;BR /&gt;
The test runs properly, but the results don't seem correct.  The log-rank test statistic my test returns is 16.0869.  This compares to my book which says the value should be "log-rank trend test chi-squared =30.051".  Is the test statistic that SAS returns not a chi-squared statistic?  Otherwise I am not sure what I am doing wrong.  I know my data set values are correct as are the variables.  Any help would be great.</description>
    <pubDate>Sat, 02 May 2009 03:39:28 GMT</pubDate>
    <dc:creator>murphy82nd</dc:creator>
    <dc:date>2009-05-02T03:39:28Z</dc:date>
    <item>
      <title>Trend Test in Lifetest Proc</title>
      <link>https://communities.sas.com/t5/SAS-Procedures/Trend-Test-in-Lifetest-Proc/m-p/26361#M6016</link>
      <description>Hey all,&lt;BR /&gt;
I am very new to SAS, long time JMP and R user, but I need to use it to perform a trend test for a class I am taking.  I am using the following code to test for the trend:&lt;BR /&gt;
&lt;BR /&gt;
proc lifetest data=rats;&lt;BR /&gt;
time Time*Censor(0);&lt;BR /&gt;
strata Untreated Radiated RadiatedBPA /Trend test=(all);&lt;BR /&gt;
run;&lt;BR /&gt;
&lt;BR /&gt;
The test runs properly, but the results don't seem correct.  The log-rank test statistic my test returns is 16.0869.  This compares to my book which says the value should be "log-rank trend test chi-squared =30.051".  Is the test statistic that SAS returns not a chi-squared statistic?  Otherwise I am not sure what I am doing wrong.  I know my data set values are correct as are the variables.  Any help would be great.</description>
      <pubDate>Sat, 02 May 2009 03:39:28 GMT</pubDate>
      <guid>https://communities.sas.com/t5/SAS-Procedures/Trend-Test-in-Lifetest-Proc/m-p/26361#M6016</guid>
      <dc:creator>murphy82nd</dc:creator>
      <dc:date>2009-05-02T03:39:28Z</dc:date>
    </item>
    <item>
      <title>Trend Test in Lifetest Proc</title>
      <link>https://communities.sas.com/t5/SAS-Procedures/Trend-Test-in-Lifetest-Proc/m-p/26362#M6017</link>
      <description>&lt;HTML&gt;&lt;HEAD&gt;&lt;/HEAD&gt;&lt;BODY&gt;&lt;P&gt;I think we need more info...if the data is online from your text, pointing to the link would be helpful and someone can duplicate your results.&lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;I noticed 2 variables named radiated...how many levels does each have.&lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;Are all Strata being tested at the same time in your text as well? &lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;Can always check the technotes for an errors in proc lifetest and/or your text for erratas...&lt;/P&gt;&lt;/BODY&gt;&lt;/HTML&gt;</description>
      <pubDate>Fri, 24 Jun 2011 22:36:43 GMT</pubDate>
      <guid>https://communities.sas.com/t5/SAS-Procedures/Trend-Test-in-Lifetest-Proc/m-p/26362#M6017</guid>
      <dc:creator>Reeza</dc:creator>
      <dc:date>2011-06-24T22:36:43Z</dc:date>
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