Question 5: What is the estimated difference in risk of a caesarean between two women with no history of vaginal delivery, both induced, and differing in BMI by one Kg/m2?
The estimated differnce it contained in the output table:
| Variables in the Equation | |||||||
|---|---|---|---|---|---|---|---|
| B | S.E. | Wald | df | Sig. | Exp(B) | ||
| Step 1a | bmi | .088 | .020 | 19.525 | 1 | .000 | 1.092 |
| iol | .647 | .214 | 9.139 | 1 | .003 | 1.910 | |
| prevag | -1.796 | .298 | 36.311 | 1 | .000 | .166 | |
| Constant | -3.700 | .534 | 47.953 | 1 | .000 | .025 | |
| a. Variable(s) entered on step 1: bmi, iol, prevag. | |||||||
The difference in risk is expressed as an odds ratio. These are found in the column headed "Exp(B)". The estimated odds ratio is 1.092. We estimate that the odds of a caesarean section are multiplied by 1.092 for each unit difference in BMI between the two women.
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Last updated: 12 December, 2006.