Paediatricians deal with all diseases and conditions that affect children and adolescents from infancy to 18 years of age. They order tests and examinations to be used as the basis for diagnosing and treating children. Moreover, they supervise the development of children by ordering and interpreting periodic tests and examinations, ordering preventive vaccinations as well as diagnosing developmental problems. An important task of a paediatrician is to give advice to parents concerning proper care of their children and infants, as well as prevention of diseases that most commonly affect young patients.