Table 2 Cox proportional hazard ratios with clustering by study site, predicting risk of discontinuation over 12 months Main effects model Hazard ratio p injection group ( selfinjected =1 ) 0.54 (0.440.68) .00 Clinic in a rural area 1.71 (123-2 .39) .00 Education (reference. none) Primary 0.54 (0.420.68) .00 Secondary or greater 0.41 (023-2 39) .00 Parity {number of children) 0.89 (.81 0.99) .03 Husband supports family planning use 0.70 (0.550.89) .00 Youth age 1824 years 1.25 (1.01 1.54) .04 Group ' youth Multivariate analyses also include measures ofthe districts where sites were located (not shown). Likelihood-ratio test for interaction over main effects model: lR [2(1) = 7.03 Prob > 12:0.0080. The underlying Cox model is of the form: |n(hazard of discontinuation at time t) = ln(lambda_o_hat (t))+beta'l_hat*x1+ beta2_hat*x2 + (more slopes*xs), where: x1 = 1 for those who selfinject the contraceptive and 0 for those who have a provider inject the contraceptive. x2: 1 for those who attend a clinic in a rural area, and 0 for those who use a clinic in an urban area (The Group*youth row is empty in this table, but is used in another table presenting the results of a multivariate Cox model that includes an interaction term between injection group and age of the woman) What is be the value of beta1_hat, and its 95% Cl endpoints, in the underlying Cox model that these results are based upon