# Logistic regression, interactions

#### lizhealthpsych

##### New Member
I am having a nightmare and unfortunately my supervisors cannot figure this out either!

I have an equation from logistic regression, of which the equation includes an interaction variable (2 variables combined).

I need to produce a worked example, we can’t find out what happens to the baseline scores to make the interaction, within the equation.

In other words, I need to demonstrate what happens to the 2 baseline scores within the interaction, within the log regression equation.

We assumed it was variable*variable, but it is not.

Please can you help? I am due to submit my PhD and really can’t get to the bottom of this.
Thanks!

##### Ninja say what!?!
Ummm, I'm not sure what you're trying to get at here, but it sounds like you just want a description of an interaction in a logistic model (i.e. how to interpret them). Is that so?

#### lizhealthpsych

##### New Member
Thanks so much for the reply.
Yes, I have an interaction within my log regression model (equation) I need to use the model to predict outcome for the next lot of patients. So I need to know what to do with their baseline scores (I cant use them as they are as they are an interaction.

Anxiety*control over pain
Anxiety is 10
Control over pain is 2

What do I need to do to 10 and 2 because the variables anxiety and control over pain are now an interaction (combined variable)?

I hope I make sense, if not please tell me.
Liz