Great response...i should have used it as well for same call I just received.

No Caller ID and no message left.  What are these louts afraid of !

Medical Back Pain scam.  Pressed 2 to be taken off their stupid list (like I believe that's going to happen) and was immediately routed to one of the scammers, who as previous posters have indicated, are non-Americans calling from outside the US using a spoofed number that is not easily traceable by civilians.  Since they decided they needed to talk to me I decided to yell at them for a bit.  Of course they hung up, and of course I'll get more calls, since I foolishly answered, because they'll put my number on a "live number" list to sell to other scammers and lowlifes.

Caller ID says "New York  NY".  They leave no message.

I called the number back after hours (using *67 to block my number).  Their message is, "Thank you for calling.  If you would like to have your name removed from the call back list, please, press 1.  Please, allow 48 hours for the change to take effect.  Thank you."  (I never do this as it can actually make things worse)

So they spoof their caller ID and don't identify themselves on their caller ID.  Smells like a SCAM.

Others here have reported that they are pushing support for back pain through medicare.  They will want your medicare number which includes your social security number.  This allows them to potentially target you for identity theft.  However, their primary target is medicare.  The government will reimburse them for high quality equipment/medication.  You will receive either nothing or something inexpensive and of low quality.  They will pocket the large difference.

I normally do not answer my home phone and let the call go to voice mail, but I answered and a voice said this is Louis and I immediately said I don't want to talk to you Louis. He called me a [***] and hung up on me. I called back and the recording says if you want your callback number removed to press "1" and it will take 48 hours.  I am on the do not call list.  These people are scammers with no conscience. I am going to report that number to the Florida State Attorney's office.