Exercise: Caesarean section and obesity, 4

Question 4: Carry out a logistic regression using all three predictors of caesarean section. Do any of the predictors have an effect on the risk of a caesarean which is not explained by the other two?

Suggested answer

Choose Analyze, Regression, Binary Logistic. Put the variable "Caesarian section" into Dependent and "BMI", "Induction of labour", and "Previous vaginal delivery" into Independent. Click OK.

We get a lot of output, ending with:

Variables in the Equation
  B S.E. Wald df Sig. Exp(B)
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.

All three variables have small P values and are highly significant. Hence there is strong evidence that each variable has an effect on the risk of caesarean independently of the other two.

Back to Exercise: Caesarean section and obesity.

To Applied Biostatistics index.

To Martin Bland's M.Sc. index.

To Martin Bland's home page.

This page maintained by Martin Bland.
Last updated: 12 December, 2006.

Back to top.