Cocran-Mantel-Haenszel Test A method to adjust odds ratios

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Cocran-Mantel-Haenszel Test

• A method to adjust odds ratios or relative
  risks
• Yields a summary odds ratio or relative risk

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From the Task List under Describe select Table
Analysis
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Select Race, Sex and CAD from the Task Roles
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Under Tables drag CAD to the top and Sex to the
left side
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Next under Tables drag Race to the middle of the
table with Sex and CAD
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For Cell Statistics select Row percentages and
Cell frequencies
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Under Table Statistics/Association select
Chi-square tests and CMH statistics
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The first table gives the results for race equal
to AP

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Other results are the Relative Risks and the
Chi-Square results for the first table


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• A table has only one odds ratio regardless of the
  coding of the variables
• If your outcome of interest (in this example CAD)
  is 1 (or yes) for column2, use the Col 2 risks
  for a cohort study
• If your outcome of interest is in column 1 use
  the Col 1 risks for a cohort study

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The second table gives the results for race equal
to C
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Relative Risks and the Chi-Square results for the
second table


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The third table gives the results for race equal
to C
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Relative Risks and the Chi-Square results for the
third table


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The summary tables gives the combined Relative
Risks for the three tables


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The p-value is called Prob for nominal data the
3 statistics listed will be the same.

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The test for homogeneity tests if the results for
the three races are the same


The Pr gt ChiSq 0.1672 is greater than 0.05 we
cant reject the hypothesis that the results for
the three races are the same.
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Summary of results
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Relative risks (RRs) of death by sex adjusting
for CAD, DM, and CHF