How do I tell what is checked off in a multi-selection check box of a profile field?

[Jeremy8]

Hello, I am adding profile fields to my postibit_legacy template.

The first thing to do to determine whether it should be displayed or not is to see if the user actually filled it out.

If it was a single option profile field, you would only need something like this to make sure the user filled it out:

<vb:if condition="$post['field9']">

But how do I look for individual checks in a multi-selection check box?