Table 2
Concordance rates for gastro-oesophageal reflux disease in monozygotic and dizygotic twins
Twin type
Total pairs
Discordant pairs
Concordant pairs
Pairwise concordance rate*
Casewise concordance rate*
*95% confidence intervals in parentheses.
Monozygotic
928
190
70
27 (22–32)%
42 (36–49)%
Dizygotic
1032
279
50
15 (11–19)%
26 (21–32)%