Well I have done three diabetic studies for different nutrional bars and drinks. I have done studies for creams for dry skin...........I try to stay away from medication studies because of my diabetes but yet my friend did one for cholestrol and she was taking meds and of course in the study you have to change meds and her cholestrol went down 25 points so needless to say she is now taking the study meds. Once I did one for shampoo and conditoner. They pay well...the one I am doing now pays 550.00 for three visits.......not hard to take and I meet a lot of interesting people and gives me some extra cha ching money........lol...once I did one for hair remover for you legs.......lol