Many health carriers are starting to steer patients toward “more preferred” groups of doctors within their preferred provider networks.

About 21% of health plans say they use tiered networks of primary care physicians, and 21% use tiered networks of specialists, according to researchers at the National Business Coalition on Health, Washington.

Researchers are basing those figures on survey responses from about 250 carriers.

The researchers also found that 36% of participating plans say they are pooling data with at least one other health plan to come up with community provider performance reports.