WHAT IS MEDICAL SCREENING?rnWorldwide chronic diseases have become a major cause of suffering, disability and mortality. When patients are diagnosed as a result of the appearance of symptoms, it is often too late and treatment options are limited. Hoping that early diagnosis and early treatment can retard or stop disease progression, medical screening is proposed as a secondary prevention method in which people without specific medical complaints are invited to undergo interventions to identify and modify risk factors, or to find disease early in its course so that early treatment prevents further severe complications.1,2