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Frequency of preterm birth incidence in two groups
| Intervention group n (%) | Control group n (%) | Total n (%) | χ2 | Chi-square df | p | |
|---|---|---|---|---|---|---|
| Preterm birth | ||||||
| Yes | 6 (6.80%) | 18 (20.50%) | 24 (13.60%) | 6.94 | 1 | 0.008 |
| No | 82 (93.20%) | 70 (79.50%) | 152 (86.40%) | |||
| Total | 88 (100.00%) | 88 (100.00%) | 176 (100.00%) |
