Is it OK to use the ACS Statistical Tool to Compare Different Geography Levels Within Same Survey?

Hello - I am a new ACS Census Data User.  I am not a statistician, but I understand some of the basics.

This particular forum doesn't look very active, so please let me know if I should post this question to a different group.

Ultimately I want to know if it is "legit" to use the ACS Statistical Tool to compare different geographies such as State vs. County (same survey data).

Ultimately I want to compare WI State Median HH Income to various counties in WI using 2017 5-Yr Survey data.

I'm thinking it is OK to compare counties to counties since they are at the same level of detail.

But I'd like to know if there are any caveats when comparing a large geography to a smaller one.

Thank you,


ACS Statistical Tool