Screening tests come under scrutiny

CONCERN about overdiagnosis due to screening has spread from professional journals to lay books and newspapers and is a welcome development, say US experts in preventive health.

Screening methods such as PSA testing, faecal occult blood testing and mammography were facing rising public scrutiny, they said, and questions remained as to their overall benefit.

“Harms from screening programs are real; the burden of these harms can be disputed but their existence cannot,” two former members of the US Preventive Services Task Force said in an opinion piece in JAMA.

“Screening can produce iatrogenic complications... anxiety over abnormal results, and a cascade of follow-up tests and treatments.

“[It] can also precipitate over-diagnosis, the workup and treatment of conditions that qualify as disease but pose little threat to patients’ health.”

The doctors pointed to changes in screening guidelines over the years as proof of a shift away from a consensus position.

They also warned that the debate should not be viewed against a background of a medical sector attempting to cap its spiralling costs.

“Until the reality of harms becomes more palpable to clinicians and the public, concerns about the safety of screened populations will continue to be mistaken for frugality,” they wrote.

JAMA 2012: 307; 565-66