Note that when the p-value is significant, the RR confidence intervals do not include the value of one.
Why?

The variables in Table 13-7 have been examined to determine the association with length of labor.

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TABLE 13-7 Variable Maternal age <40 Yes No (reference group) Support person present Yes No (reference group) Previous birth Variables Related to Length of Labor >12 Hours Yes No (reference group) Epidural anesthesia Yes No anesthesia or IV/IM anesthesia (reference group) RR 0.87 1.00 0.43 1.00 0.21 1.00 1.20 1.00 95% CI (0.721.23) (0.310.56) (0.180.24) (1.061.34) p-Value 0.23 0.03 0.01 0.02