Mantel Haenszel

Mantel Haenszel method is one of the method to control for confounders. It gives a single summary measure of association which provides a weighted average of RR or OR across different strata of confounding factors.

To calculates in this method we first have to divide the original two by two table by different strata of confounding variable and then we calculate the weighted average of RR or OR.

formula

                                          outcome (O)
                                             +      -   
RISK FACTOR (E)     +      a.    b.       a+b
                                     -       c.    d.       c+d
         
                                             a+c.  b+d.  

RR =   (a/(a+b)) ÷ (c/(c+d))     =    a(c+d)÷ c(a+b)

OR =    a/b.  ÷   c/d.        =   ad/bc

RR (mh)     = summation (a(c+d)÷n) ÷ summation (c(a+b) ÷n)

OR (mh)     = summation (ad/n) ÷summation (bc/n)

summation is sigma, that is sum of all the values in the different two by two tables

PSM / COMMUNITY MEDICINE by Dr Abhishek Jaiswal is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
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