Screening makes sense - you find the disease early and treatment can be more effective - or so one would imagine. Cervical smears, for example, minimally invasive, cheap, sensitive and the implications of false positives are fairly low risk.
However, in recent years the evidence is starting to stack up against the benefits of routine population-wide mammography. Do the vested interests of the providers of the screening service taint the interpretation of the latest evidence? Are we at risk of ignoring good sound science in favour of 'lobbying', or are the pro-screening advocates right?
How do we decide what is reliable evidence?