WW II U-boat study helps breast screening

A simple test performed during World War II found that after just a half hour, radar duty observers became more likely to miss signs of enemy submarine activity, and consideration of the findings is being urged for British radiologists.

According to the report on the Europe Intelligence Wire, failure to detect German subs was not due to lack of concentration, but visual weariness not noticed by the observers.

“They were looking for tiny specks on fuzzy screens and the longer they went on without a break, the harder it became,” said Dr. Donald Laming, an experimental psychologist. “Looking at x-ray films can be equally hard, and after an hour or two, concentration is bound to slip. A system of frequent breaks and double-checking would achieve a 20% improvement in detection.”

“Radiologists commonly inspect 100 mammograms in an hour,” said Dr. Ruth Warren, a consulting radiologist. “We recommend that they take a half-hour break in the middle.”

The researchers also called for a second radiologist to double-check all scans in reverse order. That way, the two are less likely to concur on borderline readings.

Radiologists are understaffed and they have a huge workload. What’s desperately needed is a good automated system for screening mammograms, said Kate Law, head of clinical programs for the British Cancer Research Campaign.

“Human beings are not built for that kind of repetitive work,” she said.