Table 1.
Summary statistics for DZ and MZ twins, and comparison of the difference between these two groups.
| MZ | DZ | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Yes | No | % | Yes | No | % | OR | 95% CI | p | |
| GP | 196 | 811 | 19.5 | 178 | 848 | 17.4 | 1.20 | (0.75, 1.92) | 0.454 |
| Migraine | 70 | 937 | 6.95 | 69 | 957 | 6.73 | 0.96 | (0.55, 1.67) | 0.881 |
| Headache | 141 | 866 | 14.0 | 133 | 893 | 13.0 | 1.09 | (0.72, 1.64) | 0.679 |
| RAP | 140 | 866 | 13.9 | 123 | 902 | 12.0 | 1.21 | (0.80, 1.83) | 0.366 |
| LBP | 79 | 470 | 14.4 | 80 | 677 | 10.6 | 1.51 | (0.85, 2.66) | 0.158 |
| PP | 68 | 938 | 6.76 | 59 | 966 | 5.76 | 1.14 | (0.66, 1.98) | 0.637 |
GP = growing pains; RAP = recurrent abdominal pain; LBP = low back pain; PP = persistent pain not otherwise specified (NOS), mostly chronic; No = number without the specified condition (not pain-free controls); % = percentage with condition; OR = odds ratios compare DZ twins (preference group) to MZ twins, adjusted for age and gender whenever significant; p = p-value using the Wald test.