Well, my 57yr old Uncle would still be alive today if he hadnt done the bowel screening tests! Yep, they killed him! Told he had cancer, had big bowel op to remove tumor. Instead they bodged the op, put C-Dif into his blood stream and died two weeks later from multiple organ failure. Oh, and he never had cancer!
Having said that, the vast majority of people probably would benefit from those tests but there are always exceptions.