I use the Alerts/Directives section to track prevention issues (i.e. mammogram, colonscopy, carotid and AAA screens etc). I believe I picked this trick up from Bert in a post from 2007 or 2008. It prints up nicely on the summary sheet that way for a patient (a trick I also picked up from someone else's post yet unfortunately I don't remember who).
As far as tracking future tests however, I struggle. I use reminders to staff members to check and make sure we got results of tests ordered or to order a test. I am lucky to currently have a good team, yet this method can be risky if you don't have trustworthy staff (like I've had in the past). I agree, having a dedicated place to track prevention issues and ordered tests would be great.