In a study, the risk difference for the proportions of pre-term births among mothers with standard prenatal care versus those with intensive prenatal care was 1.5% (with a higher proportion of pre-term births among mothers with standard prenatal care). The 95% confidence interval for the risk difference was 0.75% to 2.25%. What can we say about the p-value for the associated two-sided test (testing the null hypothesis that the proportions of pre-term birth are the same across groups)? p < 0.05 p > 0.05 Not enough information to determine