Evidence-based medicine is the conscientious, explicit and judicious use of
current best evidence in making decisions about the care of individual pat
ients. One of the differential traits of the practice of public health when
compared to clinical medicine is that it does not concentrate in individua
l patients, but rather in the health problems of the population in a given
time. In public health interventions, besides the importance of efficacy, a
spects related to the process of implementation become also crucial, This p
aper develops some principles for evidence-based public health, which are t
hen applied to a given problem: tuberculosis control in our context, Tuberc
ulosis control poses challenges which go beyond clinical practice, and requ
ire a collective organized effort. This is precisely what makes it a public
health issue and not only a clinical problem, as it requires not only heal
th care dimensions but also public health dimensions, which require policie
s that are feasible, have high efficacy, and a moderate cost, To illustrate
the problem and the results of public health policies, available data and
indicators are used, with special reference to the authors experience in th
e program for the prevention and control of tuberculosis in Barcelona (Cata
lonia, Spain).