Comparability
A change in response categories may affect comparability between the 2000 sample and 2001-2010 samples. In 2000, response categories included doctor, sex partner, someone at health department, and someone else. In 2001, the categories "family member or friend" and "other" were added and "someone else" was eliminated; IPUMS NHIS codes as "other" in the same category as "Someone else."
Aside from changes in response categories there are no additional comparability issues with this variable.
