I received a letter form Indiana Dept of Revenue that my refund is under "review". Will this effect my Federal return?

[DanielV01]

Not necessarily.  The state may sometimes be asking for information that has nothing at all to do with the Federal Return, such as the Renter's deduction, Identity Verification (which they may do regardless of how the IRS is processing your return), and many other factors.  There are occasions when both entities are, in fact, reviewing your information, but typically this is not the case.  You can check the status of your Federal Refund (if you have not already received it) at the following website (click on link):  Get Refund Status - Internal Revenue Service