Screening for disease prior to the development of overt manifestation of illness , also referred to as secondary prevention, has been a mainstay of public health practice. Few would question the value of screening for cervical dysplasia/cancer, hypertension, newborn hypothyroidism and enzyme deficiencies, or hypercholesterolemia. Disease that once showing overt symptoms are often already past points of symptomatic intervention.
Notable in the 2012 Cancer statistics just released, there is multiple references to the value of screening for cervical, breast, prostate, and colorectal cancers without mention of the potential negative consequences. Screening and secondary prevention have a very clear role in public health,but also in public health objectivity remains a core value, even in passionate debates over life and death. Worse still is the confusion caused by supposed 'expert' advice that is conflicting. Groups like the Canadian Task Force on Preventive Health Care were and are designed to wade through this myriad and develop defensable recommendations that all health care workers should follow http://www.canadiantaskforce.ca/