During last 30 yrs.,more preventive medical tests have been invented. The results are negative or positive.When results are positive,we hear great appreciation.But when they are negative, some people question the costs. Do the doctors make money? Sometimes.Do hospitals or labs make money?YES. A board certified doctor is obligated to test before treating the patient even if the doctor has a hunch.A few yrs.ago,I was asked to do ERCP for blockage on saturday night.It turned out t esting showed serious infection was the cause of vomiting.ERCP was not needed and notdone,but infectious disease specialist was consulted to improve liver/kidney function.So we as specialists look for other possibilities also.