Number is legit. It is from a Health Screening compan Lifeline screening. I made an appointment with them and they left a voice message. They travel around providing many screening tests such as ultra sound, etc. testing. You will only receive this if you made an appointment - it is not telemarketing.
Yup, legit, Lifeline Screening. They offer a low cost traveling Health Assessment Service for those who don't want to line the pockets of the AMA and Pharmaceutical Companies.