Why do advertisers use testimonials?

Because testimonials can influence people.

Explanation:

Advertisers use testimonials because testimonials can influence people. This is because the testimonials show people who have had experience with the product and have had positive experiences, ie, it is proof that the advertised product is of quality and delivers what it promises. This gives the merchant credibility and can increase their sales significantly because some consumers only buy the product after hearing positive testimonials about it.

that information cannot be released except with patient permission or to immediate family members. you could state the patient is ok but you cannot give any information on the illness or on treatment being given.