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Distribution of cases (n=100) and controls (n=100) as per age at menarche
| Age at menarche (years) | Cases (%) or mean±SD | Controls (%) or mean±SD |
|---|---|---|
| Early menarche (10-12) | 24.0 | 19.0 |
| Normative menarche (13-14) | 54.0 | 48.0 |
| Delayed menarche (15-17) | 22.0 | 33.0 |
| Mean±SD* | 13±1.2 | 13.3±1.3 |
P=0.20 (Chi-square test), *P=0.35 (unpaired t-test). SD=Standard deviation
