In a matched case-control study, Odds Ratio is calculated using:

• A Standard 2×2 contingency table (ad/bc)
• B Ratio of discordant pairs: OR = f/g where f = concordant positive pairs and g = concordant negative pairs
• C Mantel-Haenszel pooled OR from individual strata
• D Ratio of discordant pairs: OR = b/c where b = case exposed/control unexposed pairs and c = case unexposed/control exposed pairs ✓

Explanation

In a matched case-control study, the analysis must account for matching. The OR is calculated only from discordant pairs: OR = b/c, where b = number of pairs in which the case was exposed and the control was not, and c = number of pairs in which the control was exposed and the case was not. Concordant pairs (both exposed or both unexposed) provide no information about the exposure-disease relationship. McNemar's chi-square test is used for significance testing.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

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