From the WSJ

The Problem: Your insurers are sharing parts of your medical history with one another -- what if that info is wrong?

The Solution: You can now get a free report of what's in your file, thanks to the Fair and Accurate Credit Transactions Act. Most people who apply for certain kinds of life and health insurance give the insurers permission to send their personal info to a central clearinghouse. There, other insurers can access it.

Cancer treatments or chronic conditions like diabetes would appear in this database. So might a history of reckless driving or risky activities like skydiving. Information usually stays on your record for seven years.

Of the some 9,000 people who saw their records this year, 300 to 400 found errors, says MIB Group, which collects the information. (Companies that underwrite group coverage usually don't report information on individuals.) You can get a free copy of your report once a year via phone at 866-692-6901.

Note: According to the intro information, they only have information if you've applied for individual life, health, or disability insurance.