Introductory Remarks on Screening

In this opening chapter, we introduce the role of clinicians and delve into their foundational responsibilities, one of which centers on the practice of screening. We offer an overview of the historical development of the screening process and expand upon the Wilson-Jungner criteria—a set of guidelines endorsed by the World Health Organization (WHO) to navigate the screening process in light of the natural progression of disease. We likewise describe the set of parameters which inform the validity, accuracy and reliability of screening tests by means of a confusion matrix, making fundamental distinctions between the contexts of screening and diagnosis.